key: cord-0001157-ka4261wc authors: nan title: ECR 2013 Book of Abstracts - B - Scientific Sessions date: 2013-03-07 journal: Insights Imaging DOI: 10.1007/s13244-013-0228-x sha: 0c26e4a92d2a2bc14d1ab7b6d70265a5c6b207a9 doc_id: 1157 cord_uid: ka4261wc nan analysis of breast MRI a dedicated CAD software was used (computer-aided analysis). It enables semi-automatic analysis of enhancement characteristics of the whole tumour (3D analysis of early vs. delayed phase) and the "hot-spot" (i.e. voxel with highest washin/washout ratio). Potential of breast MRI characteristics vs. classical prognostic factors to predict disease-related death was investigated separately and in combination using Cox regression. To identify significant and independent predictors for disease-related death, backward feature selection was applied (p entry /removal: < 0.05 /> 0.01). Results: Two-hundred and twenty-three patients were included (disease-related death: n=24/10.8%; censored: n=187/83.9%; loss to follow-up: n=12/5.4%). Mean follow-up was 4.7years. If tested separately, CR analysis identified significant potential both for breast MRI and classical prognostic factors to predict diseaserelated death (p < 0.001). If breast MRI characteristics and classical prognostic factors were used in combination, predictive performance could be further increased significantly (p < 0.05): after feature selection five classical prognostic factors (TNM stage, tumour typing, HER2NEU score) and six breast MRI characteristics (hot-spot: time to peak enhancement, washout ratio; 3D analysis: tumour volume; tumour voxels showing washout plus weak/intermediate washin and tumour voxels showing plateau and weak washin) remained in this final model as significant and independent coefficients (p < 0.05). Conclusion: Breast MRI has a significant potential to predict disease-related death in breast-cancer patients. It not only can be used as a stand-alone tool for this task but also adds significant predictive value to classical prognostic factors to stratify this endpoint. S169 A C D E F G B Thursday metabolic syndrome, diabetes and cardiovascular disease. There is a need to find a biomarker which proves to be reliable, non-invasive and easy to perform in clinical practice. Methods and Materials: Our aim was to know whether serum alanine aminotransferase (ALT) is a reliable biomarker of liver fat content in NAFLD, and to determine if the current threshold of normality for ALT is appropriate to assess the presence of liver fat. This is a cross-sectional, randomised, prospective, population-based study. We studied 120 healthy subjects with alcohol consumption less than 50 g/ week. Quantification of liver fat content was by spectroscopy 1H MR 3 T. 5% of liver fat content as the upper limit of normal for the diagnosis of hepatic steatosis. Results: There was an excellent positive correlation between liver fat content and serum levels of ALT (r = 0.73, p < 0.0001). Results of the backward step-wise regression analysis showed that serum ALT was the most important predictor of hepatic steatosis (ß coefficient=3.25). All subjects with ALT values > 37 U/L had hepatic steatosis (PPV:100%) and none of the subjects with ALT < 20 U/L had steatosis (NPV: 100%). ROC curves were created; the best cut-off value for the diagnosis of NAFLD was ALT: 23 U/L (sensitivity: 94.67%, specificity 73.91%, PPV: 85.84%, NPV: 89.47%). Conclusion: Serum ALT levels could be a reliable biomarker of NAFLD if the upper limit of normal for ALT is set at 23 U/L. Absolute quantification of phosphorus compounds in the liver on a clinical 3 T scanner Purpose: Hepatic energy metabolism plays an important role in insulin resistance and liver diseases. The aim was to establish a robust and fast method to detect and to quantify liver ATP content in molar concentrations for use in a clinical setting, i.e. large cohort studies. Methods and Materials: Healthy volunteers (n=86; 58 ± 12 years; BMI: 25.6 ± 3.1 kg/m²) consented to the approved protocol. All experiments were performed on a 3-Tesla MRI scanner (Philips Achieva 3.0 T X-series, The Netherlands). 31 P spectra were acquired using a 14-cm diameter 31 P surface coil, with the built-in 1 H body coil used for NOE enhancement and decoupling (TR: 4 sec; acquisition time: 13 minutes). Localisation in the liver was achieved using ISIS. Separately, intra-and interday variability were measured on 6 volunteers. The absolute quantification was established using matching phantoms and an external reference (MPA). Results: All peaks were well resolved with the mean SNR (γ-ATP) of 16. The concentrations were found to be 1.97 ± 0.61 mmol/l (phosphomonoester), 7.80 ± 2.11 mmol/l (phosphodiester), 1.97 ± 0.52 mmol/l (inorganic phosphate) and 2.70 ± 0.59 mmol/l (γ-ATP). The intra-and interday reproducibility was 4.5%, respectively, 1% (PME) 9%, respectively, 10% (PDE), 11%, respectively, 2% (Pi) and 9%, respectively, 3% (γ-ATP). Conclusion: The absolute quantification for large cohort studies has been successfully established on a clinical scanner. The obtained concentrations from this study agree with the concentrations from previous studies. Thus, the current method can reliably detect concentration changes above 10% in phosphorus compounds in human liver. Differential portal venous flow response to terlipressin in normal and cirrhotic rats: non-invasive assessment using phase-contrast MRI M. Chouhan, A. Bainbridge, N. Davies, R. Mookerjee, R. Jalan, S. Walker-Samuel, M. Lythgoe, S. Punwani, S.A. Taylor; London/UK (manil.chouhan@gmail.com) Purpose: Portal venous flow (PVF) measurement using phase-contrast MRI (PC-MRI) is technically feasible at 9.4T. The purpose of this study was to assess the sensitivity of PC-MRI to expected changes in portal flow after terlipressin administration and study the functional response in normal and cirrhotic rats. Methods and Materials: Eight Sprague-Dawley rats were randomised to bile duct ligation (BDL) procedure (n=4) or sham laparotomy (n=4). After 4 weeks, PVF was measured using respiratory-gated 2D PC-MRI (2 mm slice thickness, 10° flip angle and 22 cm/s velocity encoding) with a 9.4T Agilent system. Terlipressin (known to reduce PVF) was administered intravenously at a dose of 10mcg/100 g and PC-MRI measurements repeated sequentially for 30-40 minutes post-administration. Bulk PVF was normalised to explanted liver weight, obtained after termination of the experiment. Data were analysed using paired and unpaired Student t-tests. Results: Baseline liver weight normalised mean PVF in sham (143.53±14.42 ml/ min/100 g) vs BDL (79.51±44.74 ml/min/100 g) rats was not statistically significant (p=0.059). The reduction in PVF post-terlipressin was significant in sham (mean reduction of 63.48±14.28 ml/min/100 g; p < 0.05), but not in BDL (mean reduction of 55.44±35.71 ml/min/100 g; p=0.053) rats. Significant differences in post-terlipressin nadir PVF in sham (80.05±20.18 ml/min/100 g) vs BDL (24.07±14.66 ml/min/100 g) rats were, however, demonstrated (p < 0.05). Conclusion: Expected reductions in PVF were detected non-invasively using PC-MRI in both normal and cirrhotic rats. Data are suggestive of a lower baseline PVF in cirrhotics, which go on to demonstrate a different, more labile haemodynamic response to terlipressin compared with normal rats. The incidence of biological effects from 3.0 Tesla (T) MRI compared to 1.5 T: an observational study in 911 consecutive outpatients F. Alghamdi, P. Bertrand, L. Barantin, M.A. Lauvin, X. Cazals, F. Domengie, R. Bibi, D. Herbreteau, J.-P. Cottier; Tours/FR (faisal.gh.30@gmail.com) Purpose: To compare the acute biological effects of a 3.0 Tesla (T) magnetic resonance imaging (MRI) to 1.5 T MRI Methods and Materials: After MRI examination, 911 patients (449 with 3.0 T MRI and 462 with 1.5 T MRI) were presented with a verbal rating scale questionnaire consisting of 11 symptoms related to MRI examination. Chi-square tests were used to assess the relationship between the strength of the magnetic field (MF) and the incidence of the symptoms. A P value of <.05 was considered significant. Results: There was no statistically significant relationship between the strength of the MF and the incidence of the symptoms related to static MF exposure, such as vertigo (P =.13), nausea (P =.35), headache (P =.21), and a metallic taste (P =.64). A warm feeling induced by radiofrequency (RF) was significantly higher in the 3.0 T MRI (P <.0001) with a significant correlation between the mean specific energy absorption rate (SAR) and a warm feeling in the 3.0 T MRI (P <.0001). Numbness/ tingling related to the gradient MF was significantly higher in the 3.0 T MRI (P =.027). Conclusion: The thermal effect induced by the RF and the numbness/tingling induced by the gradient field were significantly higher in the 3.0 T MRI than in the 1.5 T MRI. There was no statistically significant difference between the symptoms related to static MF exposure from the 3.0 T MRI and 1.5 T MRI. double echo sequences both effects can be separated one from the other. We present an extension of this concept to multi-echo measurements. Methods and Materials: Brain perfusion measurements were performed in 10 patients as part of an ongoing study investigating the reproducibility of perfusion parameters on a 3 Tesla MR scanner (Siemens Magnetom Verio). Three slices were recorded with a temporal resolution of 2 s by means of a four echo FLASH sequence (TR = 52 ms, TE = 1.2/5/10/15 ms, alpha = 30 ¼ 70°). Evaluations of contrast to noise ratios (CNR) during the bolus passage of Omniscan (GE Healthcare) through different tissues were done with an inhouse software written in IDL (Exelis VIS). Results: The CNR is improved by a factor of about 1.8 calculating delta-R2 * from four echoes compared to calculations based on two echos. Signal intensity estimations for TE = 0 do not significantly benefit by the increased number of echoes. Conclusion: Multi-echo measurements allow for a larger dynamic range of T2 * shortening compared to single or double echo sequences, at the same time giving more signal. By extending the concept to keyhole and/or EPI sequences, covering of entire tumours could be achieved. We select patients with uni-or bi-lateral endoprostheses from 100 consecutive referrals for whole body (WB) PET/MR imaging (mMR, Siemens Healthcare). Simultaneous WB-PET/MR scanning was performed at 120 min p.i. of 300 MBq [18 F ]-FDG: 4 min/bed including Dixon Water Fat segmentation (DWFS)). MR-AC was performed using a) original MR-images (DWFS), b) as a) with implant-induced air-pockets filled with soft-tissue, c) as b) superimposed with co-registered endoprostheses from CT and d) as a) with implant-induced airpockets filled with metal. PET reconstruction after MR-AC (a-d) used AW-OSEM (3iterations, 21subsets, 2 mm Gaussian) on 344-matrices. Mean/max standardised uptake value (SUVbw) was calculated from interest volumes with 40% isocontour levels over the hips, pelvic muscle and bladder. Results: In 100 patients we found 1 and 2 uni-and bi-lateral endoprosthesis, respectively. Associated MR artefacts were much larger than the implants: 20.9% versus 2.5% of the attenuating voxels in (a) of the central hip region. MR-AC using (b) and (c) recovered FDG-distribution pattern compared to uncorrected PET (noAC) images and (a), while (d) resulted in severe overestimation (> 470% SUVmax). The relative changes in SUVmax/mean in the reference regions (bladder, pelvic muscle) from (b-d) compared to (a) were insignificantly small. Conclusion: Endoprostheses cause PET/MR artefacts and bias PET quantification. Artefacts and bias can be corrected by automated inpainting with a single softtissue composition prior to MR-AC, thus restoring quantitative activity distribution. Author Disclosures: T. Beyer: Founder; cmi-experts GmbH. In vitro comparison of ultrasound-based elastography techniques S. Franchi-Abella 1 , J.-M. Correas 2 , C. Elie 2 ; 1 Le Kremlin-Bicêtre/FR, 2 Paris/FR (stephanie.franchi@bct.aphp.fr) Purpose: Ultrasound elastography techniques are based on two different physical principal: strain and Shear Wave Velocity (SWV). The purpose of this study was to assess the performance of these two techniques in vitro on a calibrated elasticity phantom using five ultrasound diagnostic imaging system to improve clinical comprehension and use of elastography. An operator performed all acquisitions on a tissuemimicking phantom developed for elastography calibration (CIRS 049 A) containing spherical inclusions embedded in an homogeneous background (BG) of known elasticity (30 ± 5 kPa). Two inclusions were harder than the BG and two were softer (44±6 kPa, 75 ± 10 kPa, 12 ± 3 kPa and 18±4 kPa). Protocol was performed using high-frequency linear transducer on four different inclusions. Qualitative assessment was done on elastograms. Semiquantitative measurements were based on the ratio of strain or elasticities between the BG and each inclusion and were compared with theoretical ratio. Quantitative evaluation was performed with SWV techniques. Results: All techniques are adequate when assessing whether or not an inclusion is harder or softer than the BG. Semi-quantitative ratio of stiffness between two structures is not reproducible and strongly depends on the manufacturer. It is more accurate for SWV techniques. Direct quantitative evaluation of stiffness using SWV exhibits biases for soft targets but can still be used to precisely measure stiffness if bias is taken into account. Conclusion: Limitations and advantages of the different elastography techniques must be known while performing an elastography acquisition in clinical practice. Static magnetic fields in 1.5 and 3 T MR scanners do not influence perception of pain and touch compared with placebo exposition A. Pomschar, K. Kamm, R. Ruscheweyh, R. Laubender, M.F. Reiser, A. Straube, B. Ertl-Wagner; Munich/ DE (Andreas.Pomschar@med.uni-muenchen.de) Purpose: Potential biological effects of static magnetic fields have been in the focus of public debate with the European Physical Agents (Electromagnetic Fields) Directive 2004/40/EC having the potential to seriously limit MR imaging in Europe. Data on potential effects are still very scarce. We aimed to investigate the influence of homogeneous static magnetic fields in 1.5 and 3 Tesla MR scanners on pain and touch perception compared with placebo exposition. Methods and Materials: 18 healthy volunteers (age: 23 ± 1.8 years, 9 females) underwent three experimental sessions on separate days in randomised order, using field strengths of 0T (placebo scanner), 1.5 T and 3 T. Participants were blinded to field strength. No imaging sequences were acquired. In each session, a Quantitative Sensory and Pain Testing programme was performed before and after a 10-min exposure to the static magnetic field. It included thresholds for mechanical detection, mechanical pain, pressure pain, heat pain and phasic heat pain intensity ratings. A linear mixed-effects model was used for statistical analysis. Results: For 1.5 and 3 T compared with the placebo control, statistical analysis revealed no significant effect of the magnetic field for all tested qualities, thresholds for mechanical detection (p=0.82/0.09), mechanical pain (p=0.83/0.53), pressure pain (p=0.97/0.28), heat pain (p=0.53/0.38) and phasic heat pain intensity ratings (p=0.56/0.75). Conclusion: Short exposure to static magnetic fields in clinical 1.5 T and 3 T MRI scanners had no significant effect on pain and touch perception compared with a placebo exposure. plaque has formed correlating with cardiovascular risk factors. The present study aims at investigating whether there are differences in the carotid wall thickness and echogenicity between patients with IBD and well-matched healthy controls by high-resolution ultrasonography of the carotid arteries. Methods and Materials: 31 IBD patients (19 male, mean age: 36.9 yrs, crohn/ Ulcerative colitis: 19/12, 17 smokers) and 29 healthy controls (15 male, mean age: 36.1 yrs, 16 smokers) underwent high-resolution ultrasonography of the carotid arteries. The following variables were recorded in bilateral common carotid arteries: 1) IMT at 5, 10 and 15 mm from the carotid bulb, 2) EMT (the distance between the common carotid wall and the internal jugular vein) and 3) EC. Results: Common carotid artery IMT (0.000 < p < 0.01, T-test) and EMT (p < 0.001, T-test) were significantly higher in IBD patients compared with controls. No difference in EC was found between IBD patients and controls. No difference in IMT, EMT and EC was found between Crohn's and ulcerative colitis patients. Smokers IBD patients had significantly higher IMT and EMT values than smokers controls (0.002 < p < 0.022, T-test). Conclusion: IBD appears to be a risk factor for development of early atherosclerosis as showed by greater values of carotid IMT and EMT in IBD patients compared with healthy controls irrespective of smoking history and type of IBD disease. Purpose: To evaluate the accuracy of the preliminary CT interpretation made by the radiology residents in the emergency department. During four periods of 20 consecutive days, attending radiologists prospectively recorded any disparity between their own CT interpretation (reference standard) and the preliminary interpretation delivered by the emergency radiology residents. Disparities were recorded during both regular hours and on-call time. A misinterpretation was considered major when potentially life-threatening within hours after admission. The total number of CT performed during the survey was recorded and further classified into neuroradiological and body examinations. A rate of disparities was calculated for all CT examinations and also for body and neuroradiological cases. Results: A total of 3044 emergency CT examinations were performed during the survey: 1568 (51%) were body CT and 1476 (49%) neuroradiological cases. Disparities were reported in 145 (4.8%) of all CT examinations: 0.8% (25/3044) were major misinterpretations (17 body, 8 neuro). There were 100/1568 (6.3%) disparities reported in body CT versus 45/1476 (3%) in neuroradiological examinations (p=0.001). No significant difference was found when comparing disparities recorded during regular working hours (47/1083 (4.3%)) versus on-call period (98/1961 (5%)), p=0.47. Our results show that disparities occur most frequently in emergency body CT examinations, but major disparities represent a small proportion of all misinterpretations. The detailed analysis of our data allows comparison and Purpose: Detection of abdominal injury is a very important component in trauma management, so an accelerated assessment of liver and spleen injuries including their degree of severity is necessary. There is a good case to believe that in stress situations this subjective performance results in diagnostic mistakes. Structured objective scores as the Organ Injury Scale (OIS) drawn up by the AAST are a valuable guidance for objective trauma assessment. Aim of our study was to evaluate retrospectively whether a structured approach using the OIS differs to real-time-diagnosis. Methods and Materials: The OIS was applied by an experienced radiologist on CT data of 53 patients which underwent CT laparotomy after abdominal trauma. These results were correlated with the original text of the initial CT findings. Finally, we compared both with the intraoperative findings gathered from the surgery report. Results: Regarding the original CT report we found a mean divergence of 0.68 ± 0.8 to the OIS found in the surgery report for liver injuries (0.69 ± 1.17 for spleen injuries). In comparison with the structured approach, where we detected a divergence of 0.8 ± 0.68 (0.47 ± 0.77 for spleen injuries). There was no significant difference, but we detected a lower rate of over-diagnoses in both approaches. Conclusion: A structured approach to abdominal trauma using an imaging checklist does not lead to a significantly higher detection rate, but reduces the rate of overdiagnoses and may be more precise in grading the severity grade plus streamlines the emergeny-CT-procedure. Comparison of efficacy and safety between distal embolisation and augmented embolisation techniques for treating blunt splenic injuries with active haemorrhage Within a two-year period, 26 consecutive patients of BSI in whom haemodynamics was stable but CT showed contrast extravasation were included in this prospectively study. We randomised them into distal embolisation group and augmented embolisation group. They were followed up twice by CT at 1 week and 3 months after embolisation. We compared their demographics, injury grades, clinical parameters, hemograms, successful rates and splenic infarct volumes between the two groups. Embolisation failure was defined as persistent hypotension that required surgery or detection of splenic contrast extravasation on follow-up CT. Complication was defined as post-embolisation splenic infarct or splenic abscess. Results: All underwent first follow-up CT, 24 underwent second follow-up CT. Of 26 patients, 17 received distal embolisation, 9 received augmented embolisation. Their basic demographics, CT injury grades, clinical parameters and hemograms did not differ. Their mean systolic blood pressure was significantly elevated after embolisation. Two (2/17, 12%) of the distal embolisation group failed and required a second augmented embolisation. None of the augmented group failed but the difference did not reach statistical significance. The mean splenic infarct volume Purpose: To evaluate whether radiographers' experience in breast imaging helps in reducing significant artefacts when acquiring dynamic breast-MRI. Methods and Materials: One experienced radiologist prospectively evaluated a total of 270 breast-MRI examinations performed by three different radiographers (R1, R2 and R3) over the period September 2011-June 2012 (90 examinations each). R1 had a 5-year experience in breast-MRI and 15 years of experience in breast imaging; R2 and R3 had no specific training in breast imaging, and 5-(R2) and 2-year (R3) experience in breast MRI. For each examination the radiologist, who was blinded to radiographer's experience, was asked to assess the presence or absence of significant artefacts, defined as motion artefacts affecting image quality and/or diagnostic evaluation. The prevalence of significant artefacts in R1, R2 and R3 examinations was tested with the Chi-square test. Results: Significant artefacts were found in 45/270 examinations (16.6%;CI95%=12.7-21.6%). In particular, significant artefacts affected 6/90 examinations (6.6%;CI95%=3.1-13.8%) performed by R1, 22/90 examinations (24.4%;CI95%=16.7-34.2%) performed by R2 and 17/90 (18.8%, CI95%=12.1-28.2%) performed by R3, with a significant difference between R1 and R2 (p < 0.05). Conclusion: Artefacts potentially affecting image quality and diagnostic evaluation are less frequent in breast-MRI examinations performed by those radiographers who combine experience in breast imaging with specific experience in breast-MRI. A possible explanation is a better understanding of disease specific problems and of the importance of empathise with the patient. Accuracy of ultrasonographic diagnosis of acute appendicitis in pregnant women N. Kokhanovsky, A.-R. Zeina, N. Reindorp, A. Levit-Kantor, Y. Glick, A. Nachtigal; Hadera/IL (nataliakoh@hotmail.com) Purpose: To assess the reliability and value of the sonographic examinations in the diagnosis of acute appendicitis in pregnant women. We obtained sonographic examinations performed on 68 pregnant women with suspected acute appendicitis retrospectively for 16 months (Sep. 2008 -Feb. 2010 . The average age of study subjects was 27.3 years, with an average gestational age of 26 weeks. Sonography was the first imaging modality employed. Surgery or clinical follow-up was the gold standard for the evaluation of sonographic performance. All examinations were performed using grey-scale graded compression in the left lateral decubitus position. The sonographic criteria for acute appendicitis were detection of a noncompressible, blind-ended, tubular, structure measuring greater than 6 mm in maximal diameter. Results: 4 patients had positive sonographic findings of acute appendicitis (5.9%). Sonographic findings were correlated with surgical findings and clinical follow-up. The diagnosis was confirmed in all 4 patients (100%). In the 64 patients with negative sonographic findings of acute appendicitis, the result for 1 patient (1.6%) proved false-negative, whereas the remaining 63 (98.4%) improved on clinical follow-up. Accordingly, sensitivity was 80.0%, specificity was 100% and overall accuracy was 98.5%. Moreover, in 4 out of the 64 patients with negative sonographic findings for acute appendicitis, a different pathologic finding such as acute pyelonephritis was identified. Conclusion: Our experience suggests that ultrasonographic examination with the optimal study protocol is a highly accurate method for the diagnosis of acute appendicitis in pregnant women and should be performed as the first imaging test. Purpose: To exploit the ever increasing quantity of routinely acquired imaging data generated in clinical practice for research, we propose an infrastructure for the automated anonymization, extraction and processing of image data stored in clinical data repositories. Methods and Materials: As proof of principle, we used this infrastructure to implement a pipeline for measuring brain volumes in clinical MRI. This fully automated system consists of four steps: subject selection using PACS query, anonymization of privacy sensitive information and removal of facial features, quality assurance on DICOM header and image information, and biomarker extraction. 1114 examinations were selected based on MRI protocol: dementia (246), multiple sclerosis (446) and a general healthy elderly population study (422) . We evaluated the effectiveness of the infrastructure in accessing and successfully extracting biomarkers from routinely acquired clinical imaging data. To prove the validity, we compared brain volumes from dementia and multiple sclerosis patients with the healthy population. Results: Success rates of 82.5%, 82.3% and 100% are achieved for the three protocol groups, respectively, indicating large amounts of routinely acquired clinical imaging data can be used for research purposes. In line with the literature, tive statistics, T-student tests for comparing groups, and Mann-Whitney tests for verifying hypothesis and item relations. Results: Most radiographers completely agree (37.5%) or partially agree (40%) that evidence-based radiology makes part of their job requirements, but only 32.5% consider it absolutely useful for developing their skills. Most research projects and papers (72.5%) are done by radiographers during their degree to develop their knowledge and quality of services rendered. Age and academic degree do not have statistical significance (p < 0.05) for evidence-based radiology; however, there is a slight increase for radiographers with higher academic degrees and for those who have greater access to research papers and literature. Conclusion: Evidence-based practice is not applied by most radiographers as a work method; however, the underlying knowledge on this thematic suggests it would be well received and developed to enhance skill, knowledge and the department general quality. Radiographers quality assurance work: resistance and cooperation R. Gullien, J.G. Andersen, A.E. Haakull; Oslo/NO (uxraul@ous-hf.no) Purpose: Explaining the radiographer-chosen improvement initiatives in quality assurance work (QAW), adjustment and progression of these initiatives and changing possible resistance to cooperation. Methods and Materials: Different implementation strategies and improvement initiatives were used in the QAW to prevent a feeling of insecurity, threatening, uneasiness, less valuable, to avoid conflicts and to enable education, training, self-assessment, improve oneself. Manager implements measurements, strategies and improvement initiatives. The employees came up with suggestions of actions, brainstorm. Voting was performed and top three were selected. Combination of suggested and specific initiatives over time: continuous individual feedback over time (baseline, after implementation, follow-up), individual assessment measured by experience in mammography, theoretical and practical training, lectures, examples, individual positioning training, reading guidelines and articles, individual feedback on positioning technique, tailored training for new employees, different checklist for employees (new/"old", inexperienced/experienced), checklist for updating knowledge, self-study, workshops, training in self-evaluation, new internal guidelines, frequent feedback if necessary, practical training with supervisor, temporarily get another kind of work, meetings and discussions, inform about QAW when job interview. Results: Positive changes in cognition, self-knowledge, personal skills, confidence in the situation, comfortable, demystified, attitude change; related to knowledge and awareness. Teamwork manager and employee with focus on improvement work and differentiate between work and employee. Conclusion: Using various strategies are beneficial, different methods to meet different needs. Top-down, bottom-up, threat-relaxation, tentative-participation, resistance-cooperation. Dialogue and cooperation between staff and management; between the radiographers are essential for success. Radiographers' knowledge about adverse reactions to iodinated contrast media A. Santos, L. Capitolina, I. Silva, A. Saraiva; Coimbra/PT (adelinosantos@estescoimbra.pt) Purpose: EudraVigilance-Pharmacovigilance is a data processing network and management system for reporting and evaluating suspected adverse reactions of medicinal products in the European Economic Area. The main purpose of this paper is to assess the level of knowledge of radiographers relatively adverse reactions of iodinated contrast media (ICM). Methods and Materials: An original electronic survey was used, which is composed of four dimensions of study to gauge radiographers' knowledge regarding the chemistry of ICM (I), potential adverse reactions (II), possible procedures to be taken in emergency situations (III) and actions to be taken under the National Pharmacovigilance System (IV), in a first phase. And throughout various European countries (Northern, Central and Mediterranean), in a second stage. Results: Only 11.5% of respondents were able to correctly answer the four questions on chemistry of ICM. However, a significant relationship between those who know the classification of ADR and who has knowledge of chemistry ICM still exists. Concerning the procedures to be taken in case of ADR, we found that only 13.3% of subjects were able to correctly identify usual emergency procedures in this type of situation and, regrettably, only 3% of the sample proved able to correctly identify all adverse reactions suggested by the questionnaire. The only method that enables epidemiological continuing surveillance safety of all drugs is the spontaneous reporting of adverse events. This pioneer B-0147 11:24 Fast search for radiology cases in hospital systems via contentbased image retrieval G. Langs 1 , R. Donner 1 , M. Holzer 1 , D. Markonis 2 , H. Mueller 2 , E. Birngruber 1 ; 1 Vienna/AT, 2 Sierre/CH (georg.langs@meduniwien.ac.at) Purpose: Efficient and quick access to comparable cases and corresponding radiology reports is crucial during radiological assessment and increases quality. Currently, in most cases search queries within a PACS are limited to meta data. brain volumes (expressed as percentages of intracranial volume) were found to be significantly smaller in patients scanned under dementia (79.7%) and multiple sclerosis (81.4%) protocols, when compared with healthy controls (82.8%). Conclusion: This demonstrates that quantitative image biomarkers can be reliably extracted from routinely acquired clinical imaging data. This enables secondary use of clinical images for quantitative biomarker discovery at a hitherto unprecedented scale. Interactive methods improve radiology long-term learning J.C. Pueyo, J. Etxano, P. Slon, R. Zalazar, J. Ros, L. García del Barrio, G. Bastarrika, A. Villanueva; Pamplona/ES (jetxano@unav.es) Purpose: Personal remote response systems (clickers) have shown to be an interesting tool to encourage participation. The aim of this study is to evaluate whether the use of clickers improves learning and retention of radiology within a group of medical students. Methods and Materials: 175 medical students attended 17 radiology lessons. Each lesson was about 145 radiological images. At the beginning of each lesson, students have a PDF with all the images corresponding to that day. At the end of each lesson, there were five interactive questions of those images using clickers. Three months later, there was an examination with multiple-choice questions. Half of the questions were images that had already been interactively worked with clickers. The other half were images of the PDFs not worked with clickers. Incorrect answer value was -0.25. To evaluate the difference in the degree of learning achieved between both methods, we analysed the index of correct and false answers of each group. Results: The averages of the correct answers were significantly higher in the group of interactive teaching than in the passive education group (63 vs 53%, p < 0.005). The percentage of incorrect answers of the interactive teaching group was significantly lower than in the other (23.4 vs. 27.4 p < 0.05). The percentage of unanswered questions was significantly lower in the interactive group (13% vs 19.5% p < 0.005). Conclusion: Interactive learning with remote response devices (clickers) is an effective method in teaching radiology, because it significantly improves learning and retention of knowledge. Purpose: To evaluate diffusion-weighted (DWI) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for diagnosis of recurrent papillary thyroid cancer (PTC) in comparison to ultrasound and peroperative and histopathological findings. Methods and Materials: Twenty-eight patients with suspicion for recurrent PTC underwent 3 T MRI, including DWI (b=0-50-100-500-750-1000 sec/mm 2 ) and DCE-MRI (25 runs; 6 seconds each; pre-, during and post-contrast). Interpretation criteria were: b1000-DWI for detection of soft tissue lesions and lymph nodes (LN); characterisation with apparent diffusion coefficient (ADC) calculated from all (ADCavg), low (ADClow) and high b-values (ADChigh); characterisation by DCE-MRI with arterial slope (AS), area under the curve (AUC) and c-peak. The ADC and DCE-parameters of tumoural and benign lesions were compared with a Mann-Witney U test. Receiver-under-the-operator-curve analysis determined a threshold from which the accuracy of functional MR-imaging was compared to ultrasound in correlation to histopathology. Results: Only ADChigh and AS showed statistical difference between recurrent tumour and benign lesions (ADChigh: p=0.002; AS: p < 0.0001). Per-neck region, b1000-DWI combined with AS yielded highest sensitivity of 93% with 98% specificity. Ultrasound showed a sensitivity of 72% and specificity of 98%. Per patient, functional MRI corrected ultrasound in only 4 patients for diagnosing tumour recurrence. However, functional MRI findings correctly changed treatment planning in 13 of 28 patients [excluding tumour recurrence (n=2), mediastinal metastatic LN (n=5), laryngeal metastasis (n=2), ipsilateral nodal skip metastasis to level II (n=2), contralateral nodal metastases (n=2)]. Conclusion: Combining b1000-DWI with DCE-MRI may show additional value to ultrasound for diagnosing and planning treatment in recurrent PTC. Diagnostic evaluation of patients with squamous cell cancer of the head and neck after free flap reconstructions -the usefulness of functional imaging techniques M. Członkowski, A. Trojanowska, P. Trojanowski, J. Klatka, A. Drop; Lublin/PL (m.czlonkowski@interia.pl) Purpose: To evaluate patients operated on head and neck squamous cell cancer and reconstructed using free tissue transfer flaps Methods and Materials: We evaluated 34 patients with T4 tumours of oral cavity, oropharynx, hypopharynx and larynx. All patients underwent surgical resection of the tumour and reconstruction with free tissue transfer flap: musculocutaneous, fasciocutaneous, osseous and osseocutaneous. Patients underwent post-operative radiotherapy. In the whole group we performed CT and/or MR study 3, 6 and 12 months after the completion of therapy. In patients suspected for recurrence based on CT/MR findings, MR diffusion-weighted imaging and CT perfusion were additionally performed. In case of positive findings these patients were qualified for surgery. Results: In 11 out of 35 patients imaging study was suggestive for recurrence (4 nodal and 7 local). In this group additional functional imaging was performed. MR DWI and CT perfusion findings were indicative of nodal recurrence in two cases and patients were operated on. Recurrence was not proven on histology in either case. In 7 patients with suspected local recurrence additional functional imaging was performed in 5 cases and the recurrence has been proven histologically in 3 cases. Conclusion: We have to be aware that functional imaging may be of little value in patients reconstructed with free flaps. Although diagnostic imaging plays a prime role in post-treatment follow-up, positive findings must be evaluated with caution. Careful reading together with ENT surgeon is vital. Purpose: Chronic bronchitis (CB) is usually caused by smoking and characterised by chronic inflammation and remodelling of the airway wall, commonly in large airways. The study purpose is to determine differences in airway wall thickness (AWT) and wall area percentage (WA%) between subjects with and without CB symptoms. Methods and Materials: 50 heavy smokers with CB symptoms (cough, mucus, dyspnoea and wheezing) and 50 heavy smokers without CB symptoms were randomly selected from 1,413 participants in a lung cancer screening trial. Airway walls were measured on images in thin-slice low-dose CT with a dedicated software tool, for airways with a luminal diameter ³5 mm in 5 selected bronchi (RB1, RB4, RB10, LB1+2 and LB10). Differences in measurements between the groups were assessed by t-test. The association between CB symptoms and AWT and WA% was analysed using multiple linear regression adjusted for age, body mass index, smoking habit, amount of emphysema, and lung function. Results: Mean AWT measured at 5 bronchi was 1.55±0.44 mm and 1.42±0.40 mm in subjects with and without CB symptoms, respectively (P < 0.001). WA% was 47±12% and 43±11%, respectively (P < 0.001). With adjustment for confounders, a significant positive association between both airway wall measurements (AWT and WA%) and CB symptoms was found for airways with a luminal diameter from 5 to 10 mm (P < 0.01). In airways with a luminal diameter ³10 mm, no significant association was found (P> 0.05). Conclusion: Patients with chronic bronchitis symptoms have thicker airway walls of airways between 5 and 10 mm diameter, not in larger diameter. Value of inspiratory and expiratory lung volume und lung density for detection of bronchiolitis obliterans syndrome ( ). There was a significant lower variation between the different kernels using IR when compared to FBP. Image noise was reduced by 27% when compared to FBP. Conclusion: Variation of quantitative emphysema chest CT parameters between different reconstruction kernels is significantly reduced with IR when compared to FBP and may increase the robustness for therapy planning. Assessing pulmonary perfusion in emphysema: automated quantification of perfused blood volume in dual-energy CTPA F.G. Meinel, A. Graef, S.F. Thieme, F. Bamberg, C. Neurohr, M.F. Reiser, T.R.C. Johnson; Munich/ DE (felix.meinel@med.uni-muenchen.de) Purpose: To determine whether automated quantification of lung perfused blood volume (PBV) in dual-energy computed tomography pulmonary angiography (DE-CTPA) can be used to assess the severity and regional distribution of pulmonary hypoperfusion in emphysema. We retrospectively analysed 40 consecutive patients (mean age 67 ± 13 years) with pulmonary emphysema, no cardiopulmonary comorbidities and a DE-CTPA negative for pulmonary embolism. Automated quantification of global and regional pulmonary PBV was performed using the syngo dual-energy application (Siemens Healthcare). We further quantified the global and regional percentage of voxels with a CT density <-900 HU. Emphysema severity was rated visually and pulmonary function tests were obtained by chart review. Results: Global pulmonary PBV showed a moderate but highly significant negative correlation with residual volume (RV) in % of predicted RV (r=-0.62, p=0.002, n=23) and a positive correlation with forced expiratory volume in 1 second (FEV1) in % of predicted FEV1 (r=0.67, p < 0.001, n=23). Global PBV values strongly correlated with diffusing lung capacity for carbon monoxide (DLCO, r=0.80, p < 0.001, n=15). Pulmonary PBV values decreased with visual emphysema severity (r=-0.46, p=0.003, n=40). Moderate negative correlations were found between global PBV values and parenchymal hypodensity in a per-patient (r=-0.63, p < 0.001, n=40) and per-region analyses (r=-0.62, p < 0.001, n=40). Conclusion: DE-CTPA allows simultaneous assessment of lung morphology, parenchymal density and pulmonary PBV. In patients with pulmonary emphysema, automated quantification of pulmonary PBV in DE-CTPA can be used for a quick, reader-independent estimation of global and regional pulmonary perfusion, which correlates with pulmonary function tests. Author Disclosures: T.R.C. Johnson: Equipment Support Recipient; Siemens Healthcare. Research/ Grant Support; Bayer Healthcare. Purpose: Brain death has adverse effects on lung perfusion and ventilation with possible damage of lung parenchyma pre-transplantation. We wanted to assess brain dead subjects treated with a new drug regime with HRCT as a pre-transplant work-up. Methods and Materials: Eleven pigs were decapitated (DC) assuring brain death, attached to ventilator and treated with a new drug regime optimising circulation thereby preventing lung edema. Thirteen non-decapitated pigs (N-DC) attached to ventilator, supported with conventional treatment served as controls. All were monitored 24h and thereafter examined with chest HRCT. Images were analysed by two radiologists using a pre-defined questionnaire assessing parenchymal and airway changes. In consensus, an overall conclusion inferred presence of edema, infection/atelectasis or airway pathology. Severity was estimated with a subjective scale. Results: After 24h there were no significant differences between the groups regarding mean arterial pressure (MAP), arterial oxygen/fraction of inspired oxygen (PaO2/FiO2), amount of infused fluid, urine production or clinical signs of edema. out BOS. Lung volume (vol), mean lung density (MLD), 10 th , 20 th , 30 th , 40 th , 50 th percentile (P10-P50), peak, full width half maximum (FWHM), percentage of high (>-300 HU, HAV) and of low attenuation values LAV) were assessed with dedicated software (MeVis Pulmo). Measurements of patients with/without BOS and patients without BOS with normal (FEV1> 90% of baseline, BOS0)/slightly reduced values for FEV1 (FEV1 81-90% of baseline, BOS0-p) were compared with independent t-test. Results: Vol, MLD, P10, P20, P40, P50, peak, and FWHM (p²0.005) in expiration scan as well as difference in volume between inspiration and expiration (p < 0.001) were significantly different in patients with/without BOS. In inspiration, P10 (p=0.017), FWHM (p=0.036) and LAV (p=0.026) showed significant differences at higher levels. Comparing patients with BOS0 and BOS0-p, P10 might be used for distinction (p=0.029). Conclusion: Expiratory lung volume and density showed significant differences in patients with/without BOS. P10 value might be used as an imaging biomarker for early detection of BOS. Author Purpose: The aim of this study was to prospectively evaluate the diagnostic value of density mappings for detection of BOS following lung transplantation. Methods and Materials: 132 CT examinations were carried out in lung transplant patients in full inspiration / expiration using a 64-row MDCT (120 kVp, rotation time 0.8 s, pitch 0.984, collimation 1.25 mm, reconstruction increment 1 mm, standard reconstruction kernel). 27 / 105 examinations were performed in patients with / without BOS (BOS 0: 80, BOS 0p: 25, BOS 1: 11, BOS 2: 5, BOS 3: 11). The assessment of AT was performed using both, a threshold-based method in expiration (HU range: -910 HU to -850 HU) and density mappings of HU values in inspiration and expiration after registration applying a threshold of -910 HU to -750 HU and HU differences ² 70 HU between expiration and inspiration. With both methods, measurements of patients with / without BOS were compared with independent t-test. Results: AT quantified with density mappings was significantly different in patients with / without BOS. Mean AT was 28% in patients with BOS and 18% in patients without BOS. Comparing patients with and without BOS AT might be used for distinction (p=0.002). AT quantified with the standard threshold-based method also showed differences between both groups, but with a lower significance (p=0.019). Conclusion: Measurement of AT with density mappings of HU-values showed a significantly better distinction between patients with / without BOS than the standard threshold-based method. Non-invasive focal therapy of organ confined prostate cancer: phase I study using magnetic resonance guided focused ultrasound technology and excision pathology for efficacy assessment A. Napoli, V. Panebianco, M. Anzidei, F. Boni, V. Noce, L. Bertaccini, G. Cartocci, F. Ciolina, C. Catalano; Rome/ IT (alessandro.napoli@uniroma1.it) Purpose: To assess safety and initial effectiveness of non-invasive high-intensity 3 T MR-guided focused Ultrasound (MRgFUS) treatment of localised prostate cancer in a phase I, treat and resection designed exploratory study. Methods and Materials: On the basis of a power analysis, 11 patients with biopsyproven focal T2 prostate cancer (low-to-intermediate risk: Gleason max 3+4), confirmed on a previous multiparametric MR exam, including dynamic contrast enhanced (DCE) imaging, underwent MRgFUS. All patients were scheduled to laparoscopic prostatectomy; MRgFUS treatment was carried out on MR identifiable lesions (max 2) using a patient-specific energy and real-time MR thermometry monitor for correct location. Non-perfused volume (VPV) in the post-ablative MRI was than compared with excision pathology for necrosis assessment. Results: No significant complications were observed in all subjects during or immediately after the procedure. Procedure was validated by pathologist that demonstrated extensive coagulative necrosis at the site of sonication surrounded by normal prostatic tissue with inflammatory changes; these features positively compared with immediate post-ablative MRI scan and NPV. At histology 10 patients were free of residual viable tumour within the treated area; in the remaining patient, 10% of residual tumour was observed within the NPV. There was a variable amount of isolated cancer tissue within non-treated parenchyma that was identifiable neither at MRI nor at biopsy. To determine the impact of axial traction during MR imaging of the ankle cartilage at 3.0 T in volunteers with respect to motion artefacts, image quality and cartilage surface delineation. Methods and Materials: Optimised coronal and sagittal T1-weighted (w) turbo spin echo (TSE) sequences with a DRIVE pulse (in-plane spatial resolution 0.21 mm), a sagittal fat-saturated intermediate-weighted (IMfs) TSE sequence and a 3D gradient echo sequence were acquired at 3.0 T in 8 volunteers with and without axial traction of 6 kg. Joint space width was measured at four locations in the tibiotalar joint. Motion artefacts, general image quality, delineation of the cartilage surface, cartilage matrix and the confidence of diagnosing cartilage pathology were evaluated independently by two radiologists. Differences were assessed using a Wilcoxon test. Results: With axial traction, joint space width increased significantly (1.7±0.5 mm vs. 0.3±0.2 mm). Consequently, delineation of the cartilage surface was rated superior in 7/8 volunteers (p < 0.05). No differences were found in motion artefacts, general image quality, and artefacts within the cartilage matrix (p> 0.1). Comparing the different sequences, Cartilage surface and matrix was best visualised by the T1-w TSE sequences with a DRIVE pulse (surface average of all regions and readers in sag T1-DRIVE vs. IMfs on a four-point scale 1.3±0.6 vs. 3.0±1.0, p < 0.05). Conclusion: Axial traction of 6 kg increases the joint space width at the tibiotalar joint, and thus better visualises the articular cartilage surface. Highest spatial resolution and visualisation of both cartilage surface and matrix were achieved by a T1-w TSE sequence with a DRIVE pulse. S188 C A D E F G B Results: All affected subjects were women between 14 and 52 years old (mean age: 40). Ischiofemoral space was significantly narrower in patients with ischiofemoral impingement when compared with control subjects (13.1 ± 4.06 mm vs 24.9 ± 4.55 mm, respectively; p < 0.01). Quadratus femoris space was also significantly narrower in affected subjects (9.4 ± 2.97 mm vs 16.4 ± 1.08 mm; p < 0.01). Inclination angle was not statistically different (p> 0.05). The degree of oedema and fatty infiltration was inversely proportional to values of ischiofemoral and quadratus femoris space. The interobserver agreement (ĸ) was 0.8 for ischiofemoral space, 0.63 for quadratus femoris space and 0.53 for inclination angle. Conclusion: Ischiofemoral impingement can be accurately diagnosed following anatomic and imaging MR criteria. US-guided viscosupplementation of the hip: therapeutic efficacy in patients affected by femoro-acetabular impingment C. Martini 1 , F. Lacelli 2 , E. Fabbro 1 , G. Ferrero 1 , G. Serafini 2 ; 1 Genoa/IT, 2 Pietra Ligure/ IT (chiarapio@libero.it) Purpose: US-guided viscosupplementation is a safe and effective therapy for symptomatic osteoarthritis (OA) of the hip and it allows to replace NSAIDs therapy and to delay prosthetic intervention. Femoro-acetabular impingement (FAI) is a cause of OA. The purpose of this work is to evaluate the efficacy of viscosupplementation as therapy of OA in patients affected by femoro-acetabular impingement. Methods and Materials: 352 patients selected by orthopaedists for hip pain and plain films signs of OA (degrees II-IV of K-L) underwent viscosupplementation (4 ml of intermediate weight hyaluronic acid for three times every 30days). Each patient was evaluated before the treatment and 1, 3, 6 and 12 months after the treatment by means of VAS and Oxford Score. Hence, these patients were divided into responsive (increase Oxford score=/> 10 and/or reduction VAS0/> 3) and non-responsive (increase Oxford score< 10 and/or reduction VAS0< 3). Then we retrospectively evaluated the plain films of the hip these patients had done before the therapy, in order to find the signs of FAI. Results: 281/352 (79.8%) patients were included into the "responsive" group; 71/352 (20.2%) in the "non-responsive" one. In the "responsive" group we found signs of FAI on the plain films of 37/281 patients (11.4%); in the "non-responsive" in 43/71 (60.5%). Conclusion: Despite viscosupplementation is an effective therapy of OA, there is an high prevalence of non-responsive among patients affected by FAI. A new way to measure lower limb length and alignment using 3D models based on biplanar linear radiography: a comparison with measurements on supine CT scans and upright full-length radiographs R. Guggenberger, C.W. Pfirrmann, P. Koch, F. Buck; Zurich/CH (romanguggenberger@yahoo.de) Purpose: To compare lower limb length and alignment angle on supine computed tomography (CT), upright full-length radiography (UFR) and 3D models based on upright biplanar radiography (BLR). Methods and Materials: IRB-approved study involving 51 consecutive patients (22 male, 29 female; mean age 68.8years; range 43-92years) scheduled for total knee replacement. Lower limb length and alignment angles were measured on CT, UFR and 3D models based on BLR using standard and extended length measurements by two independent readers. Measurements of different modalities were compared by paired t-tests, Pearson correlation coefficients and Bland-Altman analyses. Results: Mean limb lengths were 783 mm (SD±56.1 mm, range 639-927 mm), 785 mm (SD±53.0 mm, 655-924 mm), 780 mm (SD±55.4 mm, 633-921 mm) and 783 mm (SD±55.9 mm, 636-924 mm) for CT, UFR and 3D models using standard and extended measurements, respectively. Mean alignment angles were 2.3° (SD±5.5°, range -12°-20°), 2.5° (SD±6.7°, -17°-18°), 3.4° (SD±6.6°, -14°-18°), respectively. Length and angle measurements differed significantly when comparing standard 3D models to CT and UFR, respectively (p < 0.001). Pearson correlation coefficients were 0.992, 0.993, 0.995 and 0.998 for limb length and 0.968, 0.983 and 0.984 for angle measurements in CT, UFR and 3D models, respectively. Bland-Altman analyses for CT and UFR compared to 3D models showed a small positive mean difference in length using standard measurements (2.7 mm, SD±5.5; 5.4 mm, SD±13.1) and a small negative mean difference in angle measurements (-1.1°, SD±2.5; -0.9°, SD±3.1). No bias for length measurements was seen using extended measurements. Conclusion: Upright 3D models allow for lower limb length and alignment angle measurements comparable supine CT scans and UFR. Stable or unstable tear of the medial meniscus of the knee: can weight-bearing MRI solve the problem? A. La Marra, S. Mariani, E. Costantini, A. Conchiglia, A. Barile, C. Masciocchi; L'Aquila/ IT (alicelm@hotmail.it) Purpose: To assess the role of 1.5 T, dedicated low-field standard and upright-MRI in the evaluation of stable or unstable tears of medial meniscus in comparison with arthroscopy. We retrospectively reviewed and analysed 20 MRI exams (group A) of normal knee and 77 MRI exams (group B) of knee with clinical evidence of tears of the medial meniscus. In the same session, after conventional 1.5 T and "dedicated" 0.27T supine MRI exam, the patients underwent upright weight-bearing examination with the same dedicated MRI unit. In all cases sagittal and coronal SE T1-W were used. All patients underwent arthroscopy within 21 days from MRI exam. Results: In group A, no statistically significant anatomical modifications of shape, intensity and position of the medial meniscus between standard 1.5 T, dedicated supine and upright MRI were observed. In group B, the images acquired in the supine position (dedicated and 1.5 T MRI) documented in 31 cases a traumatic tear (group B1) and in 46 cases a degenerative tear (group B2). In group B1, weightbearing MRI showed presence of unstable tear only in 19 out 31 cases. In group B2, weight-bearing MRI showed a degenerative unstable meniscal tear only in 29 out of 46 cases. Arthroscopy confirmed weight-bearing MRI diagnosis in all cases. Conclusion: Our preliminary results show that upright weight-bearing MRI has wide potentials for the study of dynamic modifications in case of meniscal stable or unstable tear. Periosteal high volume image-guided injection of recalcitrant medial collateral ligament injuries: a retrospective case series analysis O. Drumm, O. Chan, P. Malliaras, D. Morrissey, N. Maffulli; London/UK (odrumm@yahoo.co.uk) Purpose: We evaluate a novel injection method, periosteal high volume imageguided injection, in the management of recalcitrant medial collateral ligament (MCL) injury of the knee. The injection, comprising 10 ml of local anaesthetic with 25-50 mg of hydrocortisone, is directed at the periosteal attachment of the MCL. 28 patients in total received the intervention between June 2009 and November 2011 at a London hospital. Each was asked to complete a study-specific questionnaire including a visual analogue scale (VAS) and the International Knee Documentation Committee (IKDC) subjective knee form (to describe symptoms pre-injection and at follow-up). Results: 68% of patients responded (n=19). Three patients were omitted according to the exclusion criteria. 31.3% of patients (n=5) were professional athletes. Mean duration of symptoms was 5.4 (SD=6.6) months. Patients reported a mean improvement on the VAS of 75.4% (SD=23.7). There was a significant improvement in IKDC scores (mean difference of 42%, SD=14.2) pre-and post-injection (p=0.01). 62.5% of patients (n=10) had returned to their previous level of sport at follow-up including all the professional athletes. Knee symptoms returned to normal in 50% (n=8), and improved substantially in a further 37.5% (n=6). The remaining 12.5% (n=2) experienced an initial improvement but symptoms recurred. Conclusion: Periosteal high volume image-guided injection is a useful treatment for recalcitrant MCL injury, a common sports injury that can result in lengthy periods of missed training and competition. Results are encouraging, particularly amongst the professional athletes studied. Ischiofemoral impingement, do you want to believe? R. Prada, R. Oca, A. Rocha, L. Fernández, M. Costas, G. Tardáguila; Vigo/ES (roqueoca@hotmail.com) Purpose: To find out if there are anatomic and imaging MR criteria to diagnose ischiofemoral impingement. Methods and Materials: 290 MRIs of the hip were retrospectively reviewed from August 2011 to September 2012. A total of 9 ischiofemoral impingement were diagnosed and 20 normal patients were included as control. Ischiofemoral space, quadratus femoris space and femoral inclination angle were measured independently by two blinded musculoskeletal radiologists. The degree of oedema and fatty infiltration in the quadratus femoris muscle were also assessed visually. Differences in ischiofemoral space, quadratus femoris space and femoral inclination angle were studied between pathological and control cases. The interobserver reliability was obtained for quantitative variables. Purpose: To assess the value of oral effervescent powder administration for CT evaluation of the oesophagus, quantitatively and qualitatively. Methods and Materials: 42 patients (27m/15f, mean age 57y) referred for thoracoabdominal staging CT were included in this prospective IRB-approved study. Contrast-enhanced imaging was performed on a 64-slice CT-scanner after oral administration of 3 g effervescent powder immediately before image acquisition. Oesophageal distension was assessed at three levels (proximal/middle/distal) by volumetry of the inner (ID) and outer diameter (OD). Two blinded readers separately evaluated oesophageal distension in the corresponding segments on a three-point scale. At an interval of two weeks, both readers in consensus decided on the number of diagnostic oesophageal segments in each patient in terms of the possibility to decide upon a potentially underlying pathology. Findings were compared with results from a matched control group. Quantitative and qualitative results were compared (T-Test, Mann-Whitney U Test). Inter-observer variability was calculated (weighted-Cohen-κ). Results: ID and OD were significantly larger in all oesophageal segments after effervescent powder administration as compared to the control group (p < 0.05; mean ID: 1.13 vs. 0.14, mean OD: 2.17 vs. 1.26). Further, oesophageal distension was rated significantly better, with a good inter-observer variability (mean weighted κ=0.75). At consensus evaluation, 93 oesophageal segments (74%) were rated as diagnostic in the effervescent group, versus 49 segments (38%) in the control group (p < 0.0001). Conclusion: Correctly timed oral administration of effervescent powder results in good distension of the oesophagus, allowing readily assessment of the wall at contrast-enhanced CT as compared to studies without effervescent powder. 15 DE (MarcAndre.Weber@med.uni-heidelberg.de) Purpose: To prospectively evaluate whether dynamic contrast-enhanced (DCE) MRI can assess vascularity within pseudarthrotic clefts and predicts clinical outcome better than the clinical non-union scoring system (NUSS). Methods and Materials: Sixty-four patients (mean age, 49.3 years) with nonunion of an extremity fracture in computed-tomography received 3-Tesla MRI including DCE (coronal T1-weighted fat-saturated VIBE, TR/TE=3.76/1.35 ms, 17 measurements, 2 mm slice thickness) after 0.1 mmol/kg body-weight of gadoterat. We assessed vascularity within the pseudarthrotic cleft using a region-of-interest analysis. Signal intensity curves were subdivided into those with more intense contrast-agent uptake in the pseudarthrotic cleft than in normal adjacent muscle tissue (vascularised non-union) and those with similar or less uptake. The pharmacokinetic parameters of the Tofts model (Ktrans, Kep, iAUC, Ve) were correlated to the clinical outcome at one-year follow-up (n=37). Results: Despite inserted osteosynthesis material, DCE parameters could be evaluated in n=60 at first visit. Sensitivity/specificity of vascularised non-unions as indicator of good clinical outcome was 77.3%/46.7% compared to 95.5%/26.7% using NUSS. Logistic regression revealed non-significant impact of NUSS on clinical outcome (p=0.27, odds ratio=0.97). At first examination, median iAUC (initial area under the enhancement curve) was 24.13 in patients with good outcome compared with 10.96 in non-responders (p=0.032), while Ktrans, Kep, and Ve were not significantly different. Using a receiver operating characteristic analysis, sensitivity/specificity of iAUC at the optimal cut-off value of 17.5 to predict outcome was 68.2%/76.9%. All pharmacokinetic parameters did not change significantly at the one-year control (n=18). Purpose: Imaging-guided thermal ablation has become the therapy of choice among the different treatment strategies of symptomatic Osteoid Osteoma lesions. In this descriptive, prospective study, our objective was to evaluate typical post-procedural MR-imaging characteristics following MR-guided laser ablation of Osteoid Osteoma. Methods and Materials: 35 patients with Osteoid Osteoma treated with MR-guided laser ablation underwent follow-up MR-Imaging immediately after the procedure as well as after 3, 6, 12, 24, 36 and 48 months. Imaging protocol included fatsaturated T2w SPIR TSE, non-contrast and contrast-enhanced T1w TSE images and subtraction images. MR images were jointly reviewed by two radiologists, regarding the appearance of treated areas, nidal enhancement and presence of side effects such as bone oedema and soft tissue enhancement. Imaging was correlated to clinical status. Results: Mean follow-up time was 13.9 months. 28 patients showed a postprocedural target-sign appearance with subsequent "positive inward fusion" of the different zonal compartments. Post-procedural MR-imaging can support evaluation of therapeutic success. Characteristic MR findings correlated well with the clinical status. Conclusion: Interpretation of post-procedural follow-up MR-imaging after laser ablation of Osteoid Osteoma may contribute to understanding of histopathological post-therapeutic changes and cornerstones of therapeutic success. S190 C A D E F G B Results: The mean value of Dmax obtained by surgical specimen was 57.45 mm (range 10-250) versus 70.73 mm (range 16-195. 3) of Dmax measured through MDCT. If the Dmax values were stratified into three groups (group 1 smaller than 45 mm, group 2 between 45 and 80 mm, group 3 bigger than 80 mm), a correlation with MDCT results of 62.22, 65.90 and 100%, respectively, was found. Conclusion: MDCT is an accurate technique to obtain an appropriate preoperative definition of Dmax, within the limits of tumour bigger than 45 mm. The revaluation of each case with Dmax smaller than 45 mm will supply additional information about the discrepancy (retraction of the stomach following immersion into formalin, diffusion in the submucosal layer). Percutaneous endoscopic gastrostomy (PEG) and jejunostomy (PEJ) placement guided by CT fluoroscopy with or without simultaneous endoscopy in otherwise untreatable patients C. DE (christoph.trumm@med.uni-muenchen.de) Purpose: Percutaneous endoscopic gastrostomy (PEG) or jejunostomy (PEJ) is substantial for patients with swallowing disorders to maintain enteral nutrition or to palliatively decompress intractable small bowel obstruction. Endoscopic placement can be impossible due to previous (gastric) operation, obesity, hepato-splenomegaly, peritoneal carcinosis, inadequate transillumination or obstructed passage. Computed tomography (CT) fluoroscopic guidance with or without endoscopy can enable the placement of a PEG/PEJ if endoscopically guided placement fails. Methods and Materials: 101 consecutive patients were referred to our department for feeding support (n=87) or decompression (n=14). Reasons were: ENT tumour (n=51), oesophageal cancer (n=19), mediastinal mass (n=2), and neurological disorders (n=15). Decompression tubes were placed because of cancer (n=13) or Crohn's disease (n=1). The following approaches were chosen: I. CT fluoroscopy and simultaneous gastroscopy (n=61), II. CT fluoroscopy and inflation of the stomach via nasogastric tube (n=29), and III. direct puncture under CT fluoroscopic guidance (n=11). Results: CT fluoroscopy-guided PEG/PEJ was feasible in 89 of 101 patients. No procedure-related mortality was observed. One tube was misplaced into the colon in a patient with a history of gastrectomy. No complication was seen after removal. Minor complications were dislodgement (n=17), peristomal leakage (n=7), wound infection (n=1), superficial skin infection (n=6) and tube obstruction (n=2). Conclusion: CT fluoroscopy-guided PEG/PEJ is feasible and safe, and provides adequate feeding support or decompression. It offers the benefits of minimally invasive therapy even in patients with contraindications to established endoscopic methods, combining the advantages of both techniques. Long-term complications -mainly tube-related problems -are easily treated. CT assessment of post-resection arterial stumps for right-sided colorectal cancer: a potential marker of quality of resection? T.L. Kaye, D.G. Jayne, N.P. West, D.J.M. Tolan; Leeds/UK (thomas.kaye@leedsth.nhs.uk) Purpose: There is evidence that the quality and extent of colonic resection affects tumour recurrence rates and patient survival. This is currently evaluated by pathological analysis of the resected specimen. Analysis of post-resection arterial stumps via routine follow-up CT could act an alternative in vivo marker. Methods and Materials: Staging and follow-up CT scans from 156 patients with right-sided colorectal tumours were analysed. Pre-operative arterial anatomy and post-operative arterial stumps were demonstrated using multi-planar reformats and volume rendering techniques. Methods of stump identification, stump length and stump orientation were recorded. Results: Ileocolic (98.7%), middle colic (94.2%) and right colic artery (23.7%) identification was comparable with catheter angiogram studies. Mean time interval between staging and analysed follow-up CT was 25 months. Post-resection ileocolic stumps were consistently identified (88.4% of cases). In the vast majority of cases this was via a thrombosed vessel (97%). There was a wide variation in ileocolic stump length (2.5 -74.3 mm, mean 27.6 mm, standard deviation 13.5 mm). Conclusion: To the best of our knowledge this is the largest study to date demonstrating arterial stumps post colonic cancer resection. It is the first to consistently identify stumps years after colonic resection using routine surveillance (portal venous) CT. CT-based stump length analysis may therefore have potential as an in vivo marker of extent and quality of surgical resection. Prospective study of using balloon duodenography catheters in CT enteroclysis for small bowel diseases K.C.H. Lau, L.M.F. Tee; Hong Kong/HK Purpose: To determine the usefulness of using balloon duodenography catheters (BDC) for CT enteroclysis (CTE), with a comparison of small bowel distension in using BDC and nasogastric catheters (NC). One of the limitations of CTE is the suboptimal distension of the bowels, especially the distal ileum. Using BDC, there is less reflux of contrast into the stomach and should have more contrast in the distal small bowel. The study protocol was approved by the HA KWC research and ethics committee and all patients gave written informed consent for the examination and this study. From May 2011 to July 2012, CTE was performed in 60 consecutive patients with random allocation of 27 patients using BDC and 33 patients using NC. All catheter insertions and CTE examinations were performed according to department protocol. Small bowel distension was differentiated into four regions (proximal jejunum, distal jejunum, proximal ileum and distal ileum) and given a score from 1 to 3 (1 -< 20 mm, 2 -20-30 mm, 3 -> 30 mm). Results: Distension of proximal and distal ileum was better with BDC than NC (p < 0.05: statistically significant difference). No significant difference was present for others sites (p> 0.05). Conclusion: Our study shows statistically significant better distension of the proximal and distal ileum, with the use of BDC when compared with NC. This is of particular use, as the distal ileum is a common site of small bowel diseases. With better bowel distension, this would suggest that using BDC would help to further improve the accuracy of CTE. Role of preoperative imaging with multidetector computed tomography (MDCT) in the management of patients with gastroesophageal reflux disease (GERD) symptoms, candidate to sleeve surgical revision M. Rengo, D. Caruso, F. Vecchietti, M.M. Maceroni, G. Silecchia, A. Laghi; Latina/ IT (marco.rengo@gmail.com) Purpose: To evaluate if multidetector computed tomography (MDCT) can be helpful and useful in the decision-making process in sleeve patients with gastroesophageal reflux disease (GERD) symptoms and to demonstrate the reproducibility and accuracy of the technique. Methods and Materials: Twenty-three patients submitted to LSG, complaining upper GI symptoms and/or weight regain and scheduled for a sleeve surgical revision were investigated. All patients underwent MDCT scan, upper GI barium swallow study and endoscopy. MDCT was compared with barium and endoscopy features as concern: oesophageal dilatation, neo-fundus development and volume, hiatal hernia, sleeve size in toto and atrum dilatation. All patients underwent laparoscopic sleeve revision. Surgical findings were considered "as gold standard". Results: A total of 21 patients with hiatal hernia, neo-fundus or sleeve dilatation underwent surgical correction. All findings identified at MDCT were confirmed by intraoperative findings. The presence of hiatal hernia was significantly underestimated by both barium and endoscopy with a sensitivity of 57.1% and 50%, respectively (P=0.04, P=0.02). Conclusion: MDCT is an accurate method for the detection of hiatal hernias and quantification of gastric volumes and can be considered as non invasive method to guide surgery. Purpose: The maximum tumour diameter (Dmax) is a prognostic factor in patients with gastric cancer, considering its dependence on the depth of invasion. The aim of our work has been to evaluate the accuracy of MDCT in the preoperative definition of Dmax in patients with gastric cancer, assuming surgical specimen measurements as gold standard, in order to obtain a pre-surgery prognostic evaluation. Methods and Materials: Pre-surgery CT examinations of 104 patients (mean age 68.81, range 25-90) with diagnosis of gastric cancer were evaluated retrospectively and in a blind fashion by a radiologist with expertise in the oncologic field. The Dmax measured was obtained through 2D multiplanar curved reconstruction (ADW 4.6 GE Healthcare). The results were compared with macroscopic data after surgery. S191 A C D E F G B Thursday B-0199 15:21 Pilot study to assess the diagnostic performance of MRI in the identification of adhesions between the abdominal wall and small bowel loops, using a time-efficient protocol A. Gupta, A. Hansmann, P.F.C. Lung, R. Tandon, R. Ilangovan, M. Marshall; Purpose: Abdominal adhesions following surgery are the commonest cause of small bowel obstruction and may complicate subsequent surgery. Accurate identification of adhesions has been reported using MR fluoroscopy sequences. We report our results utilising a time-efficient protocol. Methods and Materials: 10 patients scheduled for open colorectal surgery and who had undergone previous abdominal surgery were recruited over 4 months (mean age 44, range 29-59). The abdomen was divided into 9 segments prior to MR and surgery enabling accurate correlation. Using a 1.5 T scanner (SiemensAvanto), T2 sagittal, axial, sagittal true-FISP 30s cine sequences were obtained (slice thickness 1 cm), in inspiration, expiration and abdominal strain. Scanning time was 8 min. Adhesions were identified by finding angulation, fixation or altered peristalsis. 4 readers analysed the images independently, providing a consensus opinion on the number and location of adhesions. Laparotomy was the gold standard. Results: 90 abdominal segments were evaluated with adhesions identified in 44% at laparotomy and 34% on consensus MR. 31 segments demonstrated adhesions on MR; 74% correlated at surgery, whilst the remainder were found in adjacent segments (26%). Using a 2x2 table, sensitivity was 60%, specificity 86%, with positive and negative predictive values of 77% and 73%, respectively. Overall accuracy was 74%. Conclusion: Our results suggest utilisation of a time-efficient MR protocol in identifying adhesions between the bowel and anterior abdominal wall is feasible in a busy unit, and may represent a non-invasive application in the research of adhesion-preventative techniques. Reader performance rose during our study and further improvements may be realised in a larger trial. 14:00 -15:30 Room F1 Oncologic Imaging New biomarkers for tumour quantification Purpose: Patients with lung cancer often suffer additional chronic lung diseases, and often these patients present with FDG avid mediastinal lymph nodes due to inflammatory reasons rather than malignancy. FDG-PET is the leading imaging modality for N-staging in lung cancer patients; however, in patients with doubtful FDG-PET status, 3D CT histogram analysis might give an additional value to diagnostic imaging. In this investigation 3D CT histogram analysis was used to identify metastatic lymph node involvement in lung cancer patients in correlation to FDG-PET/CT. Methods and Materials: 38 lymph nodes from 32 patients aged 43-76 years diagnosed with lung cancer were investigated. FDG-PET/CT was performed prior to surgery/biopsy according to clinical schedule. Lymph node assessments were acquired using FDG-uptake and 3D CT histogram analysis on the basis of non-enhanced CT scans. For computing the histograms, the lymph nodes were segmented by a semi-automatic algorithm; the segmentation result was corrected manually if required in certain cases. Both imaging findings were correlated with the results from the histological gold standard study. Results: 21 positive and 17 negative histologically proven lymph nodes were successfully analysed by 3D CT histogram. The histological positive lymph nodes presented a median CT HU value of 34.5 while histological negative lymph nodes presented a median CT HU value of 7.6. Findings were independent of the FDGuptake value. Conclusion: 3D histogram analysis seems to be a very promising and valuable imaging surrogate for N-staging stratification in patients with lung cancer with doubtful glucose uptake in FDG-PET. Evaluation of Crohn's disease recurrence in patients with ileocolic anastomosis: value of computed tomography enterography with water enema F. Paparo, M. Revelli, C. Puppo, I. Garello, L. Bacigalupo, L. Rollandi, R. Piccazzo, A. Garlaschi, G.A. Rollandi; Genoa/ IT (francesco.paparo@galliera.it) Purpose: To investigate the value of computed tomography enterography with water enema (CTE-WE) in the assessment of the status of the anastomotic site in patients with Crohn's disease (CD) who had previously undergone ileocolic resection. were retrieved from our institutional radiology database, and reviewed in consensus by two gastrointestinal radiologists. The presence of CD anastomotic recurrence and its phenotype (inflammatory, stricturing, penetrating) , and the presence of inflammatory lesions involving other bowel segments beside the anastomotic site were recorded. Endoscopy and medical records were used as reference standards. Results: CT signs of CD recurrence were detected in 45 patients, including: 32 (71.12%) isolated anastomotic recurrences, 11 (24.44%) anastomotic recurrences + synchronous inflammatory lesions (SILs), 2 (4.44%) inflammatory lesions not involving the anastomotic site. Phenotypes of the 43 CD anastomotic recurrences were: 22 (51.1%) inflammatory (non-stricturing non-penetrating), 16 (37.2%) stricturing, 4 (9.3%) penetrating. No relation was found between the phenotype of CD recurrence and the type of the anastomosis (LL, TL, TT) (P = 0.1252; Chi-square test). Conclusion: CTe-WE allowed a complete characterisation of the anastomotic site and the detection of SILs, which had a relatively high prevalence in our study cohort (24.44%). Crohn's disease activity: correlation of inflammatory mediators with overall small-bowel motility S. Bickelhaupt 1 , S. Pazahr 1 , J.M. Froehlich 1 , R. Cattin 2 , H. Bouquet 3 , G. Rogler 1 , P. Frei 1 , A. Boss 1 , M. Patak 1 ; 1 Zurich/CH, 2 Biel/CH, 3 Berne/CH Purpose: Active Crohn's disease (CD) increases the level of inflammatory markers of which C-reactive protein (CRP) and calprotectin are commonly used to monitor disease activity. The aim was to evaluate the correlation between CRP and calprotectin levels and overall small bowel motility in patients with Crohn's disease assessed with MRI. Methods and Materials: 13 patients with Crohn's disease (4f/9m, mean 42y) were included in this IRB-approved prospective study. MRI (1.5-T, Philips Achieva) was performed after a 1-h preparation of 1000 ml Mannitol-Solution (3%). Cine T2w-2D-SSFP motility acquisitions (TR 2.47/TE 1.23/250 ms slice repetition time) were performed in free breathing over 69-84sec. Randomly chosen small-bowel segments were analysed in two abdominal quadrants using dedicated MR-motility assessment software (Motasso). Contraction frequency, amplitude, luminal diameter and amplitude diameter ratio (occlusion ratio, ADR) were evaluated as well as CRP (ngl/ul) and Calprotectin (ug/g) levels. Pearson's correlation was calculated. Results: Calprotectin was determined in mean 12 days (SEM±10.09) before, CRP 15 days (SD±28.80) before MRI. A significant inverse linear correlation was found between the contraction frequency and both the level of CRP (r=-0.701, p=0.008) and calprotectin (r=-0.805, p=0.001). Expansion of the mean small bowel diameter significantly correlated with calprotectin levels (r=0.857, p=< 0.001) but not with CRP (r=0.447, p=0.126). The absolute amplitude of the contractions did not correlate neither with the level of CRP (r=-0.527, p=0.064) nor with calprotectin (r=-0.612, p=0.026). The ratio describing relative luminal occlusion during contraction (ADR) significantly correlated with calprotectin (r=0.736, p=0.004) and with CRP (r=0.577, p=0.039). Alterations of overall small bowel motility during active phases of CD significantly correlate with the level of calprotectin and CRP. Author Disclosures: H. Bouquet: Employee; Fromer Employee of SOHARD AG. S192 C A D E F G B measured on FDG-PET. Treatment response was evaluated after three cycles of platinum-based chemotherapy, according to RECIST. The predictive value of texture and PET parameters have been investigated by multivariate analysis. Results: Fourteen out of 25 patients were non-responders (4 progressors, 10 stable disease). Combining heterogeneity and SUV in a unique parameter (heterogeneity*SUV), the latter was significantly higher in responders than in non-responders (medians 192.7 vs 92.8, respectively; p0< 0.0001) and showed a high predictive value: odds ratio (probability of response) of third vs first tertile was 49 (p0.003). Responses in first tertile were 1/8, in the second 3/9, in the third 7/8 (p0.007, p for trend 0.003). Tumour heterogeneity alone showed a significantly weaker predictive value, while SUV alone was not predictive of treatment response. Conclusion: The combination of texture features of tumour heterogeneity on CECT and the metabolic information provided by FDG-PET has the potential to be an independent predictor of response to first-line chemotherapy in advanced NSCLC. In particular, tumour SUV combined with heterogeneity provides an additional value compared with tumor heterogeneity alone. Purpose: To assess whether tumour heterogeneity, quantified by texture analysis on contrast-enhanced CT (CECT), can predict the response to chemotherapy in advanced non-small cell lung cancer (NSCLC). Fifty-three pre-treatment CECT studies of patients with advanced NSCLC who had undergone first-line chemotherapy were retrospectively reviewed and analysed. Treatment response was evaluated after three cycles of platinum-based chemotherapy, according to RECIST. Tumour uniformity on CT images has been assessed by a three-step method: image thresholding; multiscale filtering by Laplacian-of-Gaussian filter; quantification of texture features on filtered images using first-order statistics. The predictive and prognostic values of resulting texture parameters have been investigated by multivariate analysis. Results: Thirty-one out of 53 patients were non-responders (7 progressors, 24 with stable disease). Average overall survival was 13 months (4-35), minimum follow-up was 12 months. In the adenocarcinoma group (n=31), the tumour uniformity multiplied by the grey-level of unfiltered images (GL*uni index) has been shown to be the unique independent variable predictive of treatment response. Dividing the GL*uni index (8.5-46.6) into tertiles, lesions in the second and the third tertiles had a 8-fold higher probability of treatment response compared to those in the first (p0.02). TNM stage, sex, age and performance status did not show predictive value. No association between texture features and response to treatment was observed in the non-adenocarcinoma group. GL*uni index was not prognostic. Conclusion: Texture features of tumour heterogeneity on CECT images in advanced lung adenocarcinoma has the potential to be a predictive indicator of response to platinum-based chemotherapy. Textural analysis of lymphoma on unenhanced computed tomography: initial evidence for a relationship with tumour glucose metabolism, stage, end of treatment status and survival S. Babikir, B. Ganeshan, A.M. Groves, I. Kayani; London/UK (b.ganeshan@ucl.ac.uk) Purpose: To provide initial evidence in lymphoma for a relationship between tumour heterogeneity, as assessed by CT texture analysis (CTTA), and tumour glucose metabolism, stage, end of treatment status (EOTS) and survival. Methods and Materials: This retrospective, pilot study comprised 50 consenting lymphoma patients with consecutive routine 18 F-fluorodeoxyglucose (FDG) PET-CT scans. Texture analysis using TexRAD, (a commercially available texture analysis software), of non-contrast-enhanced CT images with lesions involved: 1) image filtration extracting fine, medium and coarse texture-scales, and 2) texture quantification using proportion positive pixels (PPP), standard-deviation (SD), and kurtosis (K). Corresponding tumour FDG uptake (standardised uptake value (SUVavg and SUVmax)), clinical-stage and EOTS from PET-CT and clinical reports were collected. Survival was assessed by optimised Kaplan-Meier analysis. Results: 7, 19, 9 and 15 patients had stages I, II, III and IV, respectively. Fine to coarse textures correlated with SUVavg (baseline-scan: SD at coarse-scale, rs=0.362 p=0.011; interim-scan: PPP at medium-scale, rs=-0.766 p=0.0001) and clinical-stage (baseline-scan: K at fine-scale, rs=0.424 p=0.002). Baseline coarse textures predicted EOTS (PPP at coarse-scale, p=0.006; K at coarse scale, p= Tumour vascularization imaging without contrast agents: the potential of IVIM-MRI M. Iima 1 , O. Reynaud 2 , T. Tsurugizawa 2 , L. Ciobanu 2 , J.-R. Li 2 , F. Geffroy 2 , B. Djemai 2 , D. Le Bihan 2 ; 1 Kyoto/JP, 2 Gif-sur-Yvette/ FR (mamiiima1@gmail.com) Purpose: To investigate the potential of IVIM MRI to evaluate perfusion and diffusion in a 9L glioma rat brain tumour model using a 17.2T MRI scanner. Methods and Materials: 14 fischer rats were studied. IVIM MRI images were acquired with 72 b values (25 b values; 2 to 160 s/mm², 35 b values; 172.5 to 935 s/mm², and 12 b values; 1150 to 3025 s/mm²). The signal attenuation curve was first fitted using a biexponential diffusion model to estimate slow and fast components fraction (fslow, Dfast and Dslow) of the pure diffusion part of the signal (for b> 500s/mm²). Then, the diffusion component was removed from the signal and the remaining signal was fitted using the IVIM model for b< 200 s/mm² to get estimates of perfusion fraction, f, and pseudo-diffusion, D*. Fitting was performed on a ROI basis and on a pixel-by-pixel basis to generate diffusion and perfusion maps. All rats were killed and histology (CD31) was obtained for comparison with IVIM parameters. Results: IVIM maps clearly highlighted areas with high and low fraction perfusion within tumours which were generally heterogeneous, as confirmed by histology. Interestingly, we found a negative correlation between the IVIM perfusion fraction and fslow, suggesting that cell density in high perfused areas is less than in other tumour parts and normal brain tissue. Conclusion: This study confirms that IVIM MRI can delineate high perfusion areas in tumours and provide information on tissue structure from diffusion parameters. Intravoxel incoherent motion (IVIM) diffusion-weighted MRI for monitoring the therapeutic efficacy of a vascular disrupting agent (CKD-516) in rabbit VX2 liver tumours I. Joo, J. Lee, J. Han, B. Choi; Seoul/KR Purpose: To evaluate the diagnostic value of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) in the quantitative assessment of therapeutic efficacy of a vascular disrupting agent (VDA) (CKD-516) in rabbit VX2 liver tumours. In 29 VX2 liver tumour-bearing rabbits (23 in the treated group and 6 in the control group), IVIM-DWIs were performed at a 3 T scanner using 12 b values before and 4 hours, 24 hours, 3 days, and 7 days after CKD-516 administration. Apparent diffusion coefficient (ADC) and true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) of tumours were compared between the control and treated groups and among time points. Correlation between change in tumour size and IVIM-DWI parameters was analysed to determine which IVIM-DWI parameters can be predictors for tumour response. The treated group showed a significantly larger increase in ADC at 24 hours, a decrease of D* at 4 hours, and a decrease of f at 4 hours and 24 hours, than did the control group (P < 0.05). In the treated group, compared to baseline values, D* and f significantly decreased at 4 hours and then recovered at 24 hours and D significantly increased at 24 hours (P < 0.005). In addition, the greater decrease in f at 4 hours correlated with the smaller increase in tumour size during the 7 days (rho=0.53, P=0.04). Conclusion: The therapeutic effect induced by VDA could be effectively evaluated using IVIM-DWI, and f could be an early predictive indicator for tumour response. Texture analysis on contrast-enhanced computed tomography combined with FDG-PET in predicting the response to chemotherapy of advanced non-small cell lung cancer M. Ravanelli, F. Ferraroni, D. Farina, M. Morassi, P. Tessitore, P. Rossini, R. Maroldi; Brescia/ IT (marcoravanelli@hotmail.it) Purpose: To assess whether tumour heterogeneity, quantified by texture analysis on contrast-enhanced CT (CECT), combined with FDG uptake at PET-CT can predict the response to chemotherapy in advanced non-small cell lung cancer (NSCLC). Pre-treatment CECT studies and FDG-PET studies of twenty-six patients with advanced NSCLC who had undergone first-line chemotherapy were retrospectively reviewed and analysed. Tumour heterogeneity was measured by texture analysis on CECT images; mean SUV from each patient was S193 A C D E F G B Thursday B-0208 15:12 Scatter amplitude is a good landmark for tumour localisation and treatment assessment in time-domain diffuse optical tomography during neo-adjuvant chemotherapy in breast cancer M. Van Purpose: Neo-adjuvant chemotherapy response may be monitored in a noninvasive way using multi-spectral diffuse optical tomography (DOT). A clinically feasible measurement method in these 3D volumes is proposed and compared with previously published whole breast measurements. Methods and Materials: Twelve breast cancer patients were included, which received neo-adjuvant chemotherapy. Four DOT scans were obtained: before therapy, after 3 and 9 weeks and pre-operative (18 weeks) . Deoxyhaemoglobin (Hb), oxyhaemoglobin (HbO2) and percentages water and lipids were measured in volumes as measured in DCE-MRI scans before therapy, centred on areas of high scattering amplitude and approximate location in pre-treatment DCE-MRI and/ or x-ray mammography. Patients were divided in responders and poor responders based on post-operative pathological assessment. Results: Responders (R) and poor responders (PR) showed statistically significant (P < 0.05) different development of Hb values at 3, 9 and 18 weeks within measurement volumes relative to the first DOT scan: 0.66/1.08 (R/PR, 3 weeks), 0.56/1.07 (9 weeks), 0.55/1.48 (18 weeks) . For HbO2 results were similar, but only significant for 9 and 18 weeks: 0.71/1.03 (3 weeks), 0.53/0.89 (9 weeks), 0.56/1.06 (18 weeks) . Percentages water and lipids were not significantly different. Whole breast measurements did not show statistically significant differences for Hb and HbO2 between responders and poor responders. Conclusion: Using the scatter amplitude to determine the tumour location in DOT volumes enables the measurement of Hb and HbO2 such that these parameters differ significantly between responders and poor responders. This potentially allows effectiveness assessment of neo-adjuvant treatment in breast cancer patients already at 3 weeks. Software validation of metastatic sarcoma lesion assessment using CT volumetric density tumour trajectory L.R. Purpose: Recent studies suggest that tumour assessment methods accounting for both tumour density and volume (SACT, MASS, Choi) add value beyond assessing axial dimensions (RECIST) or selective regions of interest (ROI). We have developed a comprehensive tumour response method termed Total Volume of Viable Tumour (TVVT) that assesses rate of change in Hounsfield unit (HU) density over treatment course (tumour trajectory), thereby quantifying viable tumour burden as a Volume of Interest (VOI). Steeper trajectories may translate to earlier determination of response versus progression. We evaluated the efficacy of experimental volume/HU (TVVT) software and criteria within our Picture Archiving and Communication System (Carestream Health, Rochester, NY) to circumscribe, segment and characterise volumetric density distribution throughout all parts of measurable lesions on CT. Comparison of response and tumour trajectory assessment between RECIST criteria and TVVT was performed in a test set of 10 patients with various sarcomas under radiologist supervision. Histograms depicting range and absolute HU for whole tumor volumes were analysed on a subset of patients. Results: Preliminary investigation shows feasibility of semi-automatic segmentation to outline and quantify density distribution in whole tumour volumes. Initial assessment of our set of metastatic lesions suggests that hypervascular sarcomas are a worthwhile study cohort. Histogram shifts appear to correlate with qualitative visual estimates of tumor necrosis whereas RECIST diameters demonstrate little or no differences. Conclusion: Comprehensive tumour analysis using volumetric density algorithms such as TVVT should more accurately reflect tumour burden and trajectory over selective linear or ROI measurements, leading to improved image-based tumour staging and response assessment. Semi-automated quantification of whole tumour burden should decrease inter-observer measurement variability, enabling more convenient, reliable imaging results for multiple contiguous vascular metastases. 0.032). Median (range) overall and disease-free survival was 34 (8-52) and 31 (3-56) months, respectively. Medium texture-scale predicted overall (baseline-scan: K, p=0.0002, interim-scan: K, p=0.0008) and disease-free survival (baseline-scan: K, p=0.0031, interim-scan: K, p=0.046). SUVmax predicted disease-free survival (baseline-scan: p=0.024). Clinical-stage did not predict EOTS and survival. Conclusion: Evidence provided suggests that CTTA offers an objective measurement of lymphoma severity on CT. The potential risk stratification and prognostic assessment implications may allow optimal selection of PET-CT candidates in lymphoma. Author Disclosures: B. Ganeshan: Shareholder; Shareholder and director of TexRAD Ltd, an imaging software company that is developing and commercialising the texture analysis software considered in this study. Improvement in both sensitivity and specificity of readers with next generation of mammography CAD V. Nikitin, I. Lossev, A. Filatov, N. Bagotskaya; Longmont, CO/US (vadim.nikitin@parascript.com) Purpose: The purpose of the study was to compare radiologist performance for screening mammography with and without Parascript® AccuDetect® computeraided detection (CAD) software. Each of 240 mammography cases (including 120 cancer cases and 120 normal cases) was reviewed by 12 radiologists without and with CAD (AccuDetect, version 6.1). The mammography cases were obtained with GE Senographe Essential and Philips MicroDose Mammography L30 full-field digital mammography systems. Each radiologist initially interpreted a case without CAD noted the findings and assigned BI-RADS category 0, 1 or 2 to the case. For each radiologist, the unassisted interpretation was "locked" before the radiologist turned on the CAD marks. After turning on the CAD marks, the radiologist could add, remove or adjust the findings noted on the unassisted interpretation as well as change the BI-RADS score for the case. Sensitivity and specificity calculations for unassisted and CAD-assisted interpretations were based on the BI-RADS category assignment dichotomization: (BI-RADS = 0) versus (BI-RADS = 1 or 2). Results: Average increase in sensitivity due to assistance of CAD is 1.5%, which translates into 18.8% of those initially missed cancers that were recognised with CAD assistance. Average increase in specificity due to assistance of CAD is 4.9%. Both increases in sensitivity and specificity are statistically significant. The study demonstrates that both sensitivity and specificity of radiologists increased with assistance of AccuDetect CAD system. Assessing the contribution of hypoxia to R2* differences between cancerous and normal prostate tissue A. Johnson, A. Latifoltojar, V. Hamy, H. Fitzke, K. Shmueli, S. Punwani; London/ UK (aj372@cam.ac.uk) Purpose: R2* BOLD MRI is proposed as a potential tool for mapping tumour hypoxia in prostate cancer. However, R2* has a complex relationship with tissue oxygenation that remains unexplored in prostate cancer. R2* is the sum of R2 (primarily reflecting tissue structure) and R2' (highly sensitive to static magnetic field inhomogeneities, e.g. from deoxyhaemoglobin). Whilst R2* changes are observed for prostate cancer, they may reflect tissue structure or oxygenation differences. This study aimed to clarify the nature of R2* change by quantifying and comparing R2* and its components (R2 and R2') for cancerous and normal prostate tissue. Methods and Materials: Twenty patients underwent 1.5 T multi-parametric (mp) prostate MRI (DWI, DCE and T2-weighted), supplemented by dual echo-time T2* and T2 quantitation and followed by biopsy. Tumour and healthy regions of interest (identified on mp-MRI and confirmed by biopsy) were contoured in consensus by two experienced observers on matched T2-and T2*-weighted images. Mean R2*, R2 and R2' were calculated and compared between cancerous and normal tissue using the student's t-test. Results: R2* and R2 were significantly greater for cancer than normal tissue (R2*: 18 ± 5 s-1 [mean ± SD] vs. 13 ± 7 s-1 respectively, p = 0.0130; R2: 11 ± 2 s-1 vs. 6 ± 2 s-1 respectively, p < 0.0001). No significant difference was found in R2' (7 ± 4 s-1 vs. 7 ± 7 s-1 respectively, p = 0.5597). Conclusion: Prostate tumour R2* values predominantly reflect differences in R2 (tissue structure) and not R2' (tissue hypoxia). S194 C A D E F G B men for diagnosis, especially when receptors have to be studied in defining the origin of axillary lymph node metastases. Purpose: Aim of this study was to determine the diagnostic performance of gadofosveset-enhanced MRI for axillary lymph node staging in breast cancer patients. Methods and Materials: Ten women diagnosed with invasive breast cancer underwent both non-enhanced and gadofosveset-enhanced 3DT1-weighted MRI. A radiologist, blinded for clinical data, evaluated all lymph nodes with regard to size, morphologic features and gadofosveset uptake. Lymph nodes depicted on MRI were matched with nodes removed during surgery. Nodal status was investigated by a blinded pathologist. Sensitivity, specificity, PPV, and NPV values were calculated. Results: A total of 152 lymph nodes were extracted during sentinel lymph node biopsy or axillary lymph node dissection of which 116 were matched with lymph nodes depicted on MRI. Histopathological examination resulted in 21 macro-metastases and 8 micro-metastases. With contrast-enhanced MRI, 20 lymph nodes were rated as true positive, 83 as true-negative, 4 as false positive, and 9 as false negative. This resulted in an overall node-by-node sensitivity, specificity, PPV and NPV of, respectively, 67% (95% CI 49-80), 95% (95% CI 89-98), 83% (95% CI 64-93) and 89% (95% CI 81-94). If ignoring micro-metastases, MRI showed a sensitivity of 87% (95% CI 68-96) and a specificity of 96% (95% CI 89-98). Calculated PPV and NPV were 83% (95% CI 64-93) and 97% (95% CI 90-99), respectively. Conclusion: This feasibility study concerning gadofosveset-enhanced MRI of axillary lymph nodes showed promising initial results. These results warrant larger studies to confirm these promising results. To assess sensitivity and specificity of prone breast 18 FDG-PET-CT for detection of lymph node metastases and to compare it with 3 T CE-MRI of the breast. Methods and Materials: 74 patients with breast cancer were included in this IRB-approved prospective study. All patients underwent 3 T CE-MRI and 18 FDG-PET-CT of the breast in the prone position. Patients were injected with ca. 300 MBq 18 F-FDG. CT data were only used for attenuation correction. In MRI lymph nodes were considered positive for malignancy if there was enlargement > 1 cm, thickened cortex, loss of fatty hilum, matted nodes or an irregular node contour. In PET-CT a lymph node was classified as positive when 18 FDG-uptake was greater than blood-pool activity. The evaluation of nodes was performed on a patient-bypatient basis. All nodes were histopathologically verified. Results: 18 FDG-PET-CT achieved a sensitivity of 79% and a specificity of 98%. PPV was 0.95 (CI 0.76-0.99), and NPV was 0.91 (CI 0.8-0.96). Diagnostic accuracy was 0.92. CE-MRI had a sensitivity of 74% and a specificity of 84%. PPV was 0.68 (CI 0.48-0.83) and NPV was 0.88 (CI 0.76-0.94). Diagnostic accuracy was 0.81. 24 nodes were positive and 50 nodes were negative for malignancy. The mean SUVmax of lymph node metastases was 5.52 (range 1.14 -12.75). Conclusion: 18 FDG-PET-CT improves identification of lymph node metastases as compared with 3 T CE-MRI. In patients with lymph nodes classified as malignant by 18 FDG-PET-CT of the breast a sentinel lymph node biopsy can be omitted and surgeons can proceed immediately to ALND. Purpose: To evaluate accuracy of US and US-guided-FNAB for diagnosing axillary metastasis in breast carcinoma patients and to determine applicability of the BI-RADS categorisation. We retrospectively reviewed data on 858 patients who underwent preoperative or prechemotherapy axillary US for axillary staging from January 2009 to December 2011. US-guided FNAB was performed if lymph nodes showed any suspicious findings according to the BI-RADS categorisation: even cortical thickening with preserved hilum, category 4a (C4a); even cortical thickening with compressed hilum or uneven cortical thickening with preserved hilum, C4b; uneven cortical thickening with compressed hilum, C4c; hypoechoic mass with loss of hilum, C5. US and FNAB findings were compared using sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) data. Results: Of 858 patients, 212 (24.7%) showed suspicious nodes on US and underwent US-guided FNAB. Of these 212 patients, 91 (42.9%) showed positive, 112 (52.8%) showed negative, and 9 showed insufficient findings on FNAB. Of 858 patients, 767 patients either with normal axillary US (n = 646) or without positive findings on FNAB (n = 121) underwent SLNB. Of these patients, 169 (22%) had metastatic lymph node. Of 91 patients with positive FNAB findings, 57 underwent neoadjuvant chemotherapy and 34 underwent ALND. The sensitivity, specificity, PPV and NPV of US were 47.6%, 86%, 60.4% and 79.7%, respectively. The PPV of US was 26.3% in C4a, 67.4% in C4b, 46.4% in C4c, 93 .3% in C5. The sensitivity, specificity, PPV and NPV of US-guided-FNAB were 71.7%, 100%, 100% and 70.2%, respectively. Conclusion: Axillary US showed high specificity and NPV. A categorisation similar to BI-RADS could be applicable for assessing axillary metastasis in breast cancer patients. Improving diagnostic yield in axillary lymphadenopathy sampling: core biopsy and vacuum-assisted core biopsy R. Salvador, X. Salvador, I. Miranda, O. Dominguez, L. Romero; Barcelona/ES (rafasalvador@telefonica.net) Purpose: To analyse and compare the tolerance of the method and the results obtained by sampling axillary lymph nodes with two different devices: large-needle (CB) and vacuum-assisted core biopsy (VACB), directed to patients where previous fine needle aspiration (FNAB) has failed to obtain material, or those with different cancers to determine the origin of the metastasic node. Methods and Materials: 22 consecutive patients, suspicious or proved to have breast cancer were included, all of them with enlarged lymph nodes and signed the informed consent. The two groups were alternatively sampled by large needle (14G) core biopsy and vacuum-assisted needle (14G) biopsy to obtain 2 cylinders in each procedure. Eleven patients in each group. The size of the sample (weight), as well as the time of the procedure from the injection of anaesthetic to the final collection of the 2 samples was recorded. Discomfort, as well as the acceptance of the method was also recorded and scored in a 4-grade scale. Results: The size of the samples obtained by vacuum-assisted method was bigger than that by core-needle (between twice and three times bigger). But the time for both procedures was similar (always 4-5 minutes). No differences were found in pain or any discomfort and tolerance of the method. Conclusion: Vacuum-assisted axillary lymph node biopsy is a procedure to obtain samples at least as safely as with core-needle biopsy and deserves bigger speci-S195 A C D E F G B Thursday Methods and Materials: 567 breast cancer patients between 2009 and 2011 underwent preoperative AxUS. Suspicious nodes as per protocol were biopsied, negative axillae proceeded to sentinel lymph node biopsy (SLNB). Patients were stratified based on number of abnormal nodes identified on AxUS (1, 2, > 2 nodes) and the number on final histology was noted. Sensitivity, specificity, positive predictive and negative predictive values for AxUS-FNAC/core biopsy were calculated. Results: 266 (46.9%) patients had positive axillary nodes on final histology with 169 detected by AxUS-FNAC (sensitivity 86.2%, specificity 100%, PPV 100%, NPV 68.6%). Patients with nodal metastases identified by AxUS-FNAC had a mean nodal burden of 7.1 nodes on histology (SEM=0.6, 95% CI=5.9-8.3; 1 node identified on AxUS=4.8 nodes on final histology, 2 nodes on AxUS=9.9 nodes, > 2 nodes=9.6 nodes) with correlation between AxUS and histology node numbers (r=0.39, 95% CI=0.24-0.51, p-value< 0.0001). AxUS-FNAC detected 63.5% of node positive patients. Mean nodal burden of patients diagnosed on SLNB with negative AxUS or FNAC was 2.4 nodes. The Z011 trial questioned the role of AxUS in preoperative axillary staging of breast cancer in cases with ²2 positive SLN. In this study, a single FNAC positive node correlated with 4.8 nodes on final histology suggesting that AxUS continues to be essential in guiding appropriate management of the axilla in breast cancer. would have undergone mastectomy due to CI, while MRI determined 18 additional mastectomies, increasing mastectomy rate from 38% to 52% (p < 0.021). In the CI group, 9 patients had multifocal, multicentric, synchronous or bilateral cancers, 9 (100%) at mammography and 8 (89%) at ultrasound; 2 mastectomies were due to false positives at both conventional tests (2/124, 1.6%). In the CI and MRI group, 30 patients had multifocal, multicentric, or synchronous bilateral cancers, 5 (17%) at mammography, 15 (50%) at ultrasound, and 29 (97%) at MRI (3 only MRI-detected synchronous bilateral cancers) (p < 0.002); 2 mastectomies were due to MRI false positives (rate 2/122, 1.6%, not significantly different from CI group, p=0.987). Conclusion: MRI was more sensitive than CI for multifocal, multicentric, or synchronous bilateral cancers. The additional mastectomy rate due to MRI was 14%. Adding MRI, the percentage of young patients conservatively treated remained near to 50%. By using solely CI or using CI and MRI, the inappropriate mastectomy rate was equal or lower than 2%. Imaging features in mammography and breast ultrasound are related to HER-2 receptor over-expression of primary invasive breast cancer A. Adams 1 , K.G.A. Gilhuijs 1 , K.E. Pengel 2 , C.E. Loo 2 , W.P.T.M. Mali 1 , S.G. Elias 1 ; 1 Utrecht/NL, 2 Amsterdam/NL (a.adams@umcutrecht.nl) To investigate what mammography and ultrasound imaging features are related to over-expression of the HER-2 receptor in invasive breast cancer. These features could give insight in molecular basis of imaging phenotype, facilitate prebiopsy patient recruitment for early-phase HER-2 targeting molecular imaging trials, and ultimately aid in predicting therapy response and prognosis. Methods and Materials: Mammography and breast ultrasound imaging features of 598 early invasive breast cancers were scored according to the 4 th edition of the BI-RADS lexicon, HER-2 status was determined on surgical specimens. Relevant imaging features to predict HER-2 over-expression were first identified by conducting a systematic review and meta analysis, and then applied in multivariable logistic regression models. Results: HER-2 over-expression was found in 80 cancers (13%). On multivariable analysis, the presence of microcalcifications (OR 3.5, 95% CI 2.1-5.8) on mammography, and posterior mass attenuation (OR 0.5, 95% CI 0.3-0.9) on ultrasound were strong, independent predictors. Less strong predictors were breast density category 3/4 (OR 0.9, 95% CI 0.5-1.6) and mass presence (OR 0.8, 95% CI 0.4-1.4) on mammography, and circumscribed mass margin (OR 0.8, 95% CI 0.3-2.1) Imaging of axillary lymph nodes in breast cancer patients: How do enhancement kinetics of contrast-enhanced lymph nodes apparent on dynamic MR-mammography correlate with standardised uptake value of 18 F-FDG PET/CT? J. Krammer, C.G. Kaiser, A. Schnitzer, S.O. Schönberg, K. Wasser; Mannheim/ DE (Julia.Krammer@umm.de) Purpose: Focusing on contrast-enhanced lymph nodes (LN) apparent on dynamic MR-mammography (dMRM) we intended to answer the following questions: 1) Is there a correlation between the maximum standardised uptake value (SUVmax) of 18 F-FDG PET/CT and maximum signal-intensity increase as well as type of signal-intensity curve (1-3) on dMRM? 2) Do contrast-enhanced LN negative on 18 F-FDG PET/CT have a significantly lesser signal-intensity increase and/or lower curve grading on dMRM compared to 18 F-FDG PET/CT positive LN? Methods and Materials: 25 breast cancer patients who underwent both 18 F-FDG PET/CT and dMRM were analysed. The mean study interval between the examinations was 7 days. The signal-intensity increase and curve type of axillary LN ³ 0.5 cm in short-axis and with predominant contrast enhancement on dMRM were analysed and correlated with the SUVmax on 18 F-FDG PET/CT. Results: 30 LN in 21 patients were 18 F-FDG PET/CT positive. There was no correlation between the maximum signal-intensity increase and SUVmax of these LN (r=0.04, p=0.05). 14 LN in 9 patients did not show an appropriate correlate on 18 F-FDG PET/CT (not visible or SUVmax²blood pool). These LN did not reveal a significantly lower curve grading or lesser signal-intensity increase compared to LN positive on 18 F-FDG PET/CT. There is no association between the uptake of 18 F-FDG and the vascularisation of axillary LN on contrast-enhanced dMRM as signal-intensity increase and curve type do not correlate with SUVmax. Unspecific contrast-enhanced LN on dMRM negative on 18 F-FDG PET/CT can frequently show enhancement kinetics equivalent to those rated positive on 18 F-FDG PET/CT. Ultrasound elastography in the diagnostic assessment of axillary lymph nodes in women presenting to a breast imaging centre L. Sim, L. Leong; Singapore/SG (gdrssj@sgh.com.sg) Purpose: To evaluate the performance of elastography in distinguishing benign and metastatic axillary lymph nodes. Methods and Materials: 67 women with 72 sonographically visible axillary lymph nodes undergoing biopsy at our breast imaging centre were evaluated independently with conventional ultrasound, elastography and combined ultrasound and elastography (CEUS). The elastogram was classified as benign or malignant, based on the strain pattern, the length and area ratios of the lesion seen on elastography versus ultrasound. Validation of radiological diagnosis was by histopathology. The sensitivity, specificity, PPV, NPV and accuracy of each test were compared individually and with CEUS. To obtain a parameter for diagnostic performance, ROC curves were plotted. Results: Of the 72 axillary lymph nodes biopsied, 33 had metastases and 39 were benign. The sensitivity, specificity and accuracy of conventional ultrasound were 93.9%, 30.8% and 59.7%, respectively. The sensitivity, specificity and accuracy of elastography were 93.9%, 97.4% and 95.8%, respectively, and that of combined ultrasound and elastography were 97%, 92.3% and 94.4%, respectively. The sensitivities of all 3 tests were similar but the specificity and accuracy obtained by elastography and CEUS were significantly better than conventional ultrasound (P < 0.0005). Elastography correctly diagnosed 96% of histologically benign lymph nodes which were deemed malignant on ultrasound. Conclusion: The use of elastography alone or combined with ultrasound has a higher specificity and accuracy than conventional ultrasound in evaluating axillary lymph nodes. Given the high specificity of elastography, biopsy could have been avoided in 96% of cases classified as malignant on ultrasound but benign on elastography. The Z011 Respiratory syncytial virus-related encephalitis: brain MR study with diffusion imaging A. Pak, S. Suh, G. Son, Y. Lee, H. Seo, K. Kim, B. Eun, N. Lee, H. Seol; Seoul/KR (suppy@korea.ac.kr) Purpose: Respiratory syncytial virus (RSV) is a common pathogen of acute respiratory infection causing significant morbidity and mortality in childhood. Among the major complications, encephalitis has been sporadically reported. We describe the incidence, clinical and MRI imaging findings of RSV-related encephalitis in this report. We retrospectively reviewed the medical records and imaging findings of patients with RSV-positive enzyme assay, admitted at the paediatric department in three urban tertiary-care hospitals of our medical centre for 7 years. There were 3856 cases with a diagnosis of RSV-bronchiolitis. Among them, 28 (28/3856, 0.73%) had taken brain MRI due to neurologic symptoms. 8 of 28 (28.6%) showed positive imaging findings. 5 of 8 positive MR imaging cases revealed non-RSV related pathology such as SDH, diffuse brain atrophy due to status epilepticus, periventricular leukomalacia, pre-existed ventriculomegaly, hypoxic brain injury. Results: There were three RSV-related encephalitis. The incidence of this entity is 0.08% (3/3856) for RSV positive enzyme assay, 10.7% (3/28) for brain MRI examination, and 37.5% (3/8) for abnormal MRI findings. The imaging findings of RSV-related encephalitis are as following: rhombenmesencephalitis pattern, rhombenmesencephalitis with acute disseminated encephalitis pattern, and limbic encephalitis pattern. Conclusion: Encephalitis rarely occurs with RSV bronchiolitis. However, when brain MR is needed in suspicion of neurologic involvement, RSV encephalitis is not uncommon among abnormal MR cases and mimics other viral and limbic encephalitis on imaging study. Physicians should be aware of this entity for proper diagnosis and neurologic care of RSV-positive patients. Cortical-juxtacortical lesions in clinically isolated syndromes: distribution and diagnostic value J.P. Salazar, C. Auger, D. Pareto, R. Mitjana, M. Tintore, J. Corral; Barcelona/ES Purpose: To evaluate presence and spatial distribution of cortical-juxtacortical lesions in patients with a clinical isolated syndrome (CIS) by using MRI-based lesion probability maps and to determine its impact to demonstrate lesion dissemination in space (DIS) according to the 2010 McDonald criteria for multiple sclerosis (MS). Methods and Materials: 65 CIS patients aged between 20 and 50 years old (mean 35.9 years) who underwent brain and spinal cord 3 T MRI within the first five months after symptoms onset. The following sequences were obtained: 1) PD and T2-weighted; 2) T2-fast FLAIR; 3) Un-enhanced and contrast-enhanced T1-weigthed; and 4) 3D double inversion-recovery. Cortical-juxtacortical lesions in each patient were identified, manually outlined and segmented into a binarized mask. A cortical-juxtacortical MRI-based lesion probability map was obtained. The 2010 McDonald criteria for DIS were assessed in each patient. Results: Cortical-juxtacortical lesions were identified in 24 patients (60%). Frontal lobe was the most affected area with an incidence of 37% of the lesions. Temporal and parietal lobes had also a significant incidence (20% and 23% Purpose: The aim of this study is to explore whether CNS hemodynamic disturbances, detected in patients with clinically isolated syndrome (CIS), correlate with executive function. Methods and Materials: Thirty CIS patients and forty-three healthy subjects matched for age, gender, education level, FSIQ, and place of residence were administered computerized tests of visuomotor learning and set-shifting ability. Regional cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) values were estimated using the dynamic susceptibility contrast-and irregular mass shape (OR 1.3, 95% CI 0.8-2.1) on ultrasound. The area under the ROC curve was 0.69 (95% CI 0.63-0.75, p < 0.001), and 0.67 after adjustment for over-optimism. Post-test probabilities of HER-2 over-expression were 23-37% for cancers with calcifications, without posterior mass attenuation, and 5-10% for cancers without calcifications, with posterior mass attenuation. Conclusion: Microcalcifications on mammography, and posterior acoustic attenuation of masses on ultrasound were predictors of HER-2/neu over-expression, indicating that imaging characteristics reflect molecular expression patterns in breast cancer. Purpose: To study regional changes in brain metabolites during early HIV infection compared with later stage HIV infection and HIV-seronegative controls. enhanced T2*-weighted MRI (DSC-MRI) technique in 20 regions of interest in normal appearing white matter (NAWM) and normal deep grey matter (NDGM) structures bilaterally, that serve as integral components of brain circuits responsible for visuomotor learning and executive functions. Results: CIS patients showed significantly elevated reaction time (RT) on both tasks, while their CBV values were globally increased. Significant, positive correlation coefficients were found between error rates on the inhibition condition of the visuomotor learning task and CBV values in both thalami and occipital, and periventricular NAWM, bilaterally. On the set shifting condition of the respective task significant positive associations were found between CBV values in the semioval centre and periventricular NAWM bilaterally and error rates, between CBF values in both thalami and error rates, and between CBF values in the left parietal NAWM and right caudate and RT. Conclusion: Impaired executive function in CIS patients, including inhibition and set shifting abilities, correlated positively with elevated regional CBV values thought to reflect active widespread brain inflammatory processes. The "central vein sign": is there a place for susceptibility-weighted imaging in possible multiple sclerosis? T. Kau, M. Taschwer, M. Schönfelder, J.R. Weber, K.A. Hausegger; Klagenfurt/ AT (t.kau@gmx.at) Purpose: Susceptibility-weighted imaging (SWI) may have the potential to depict the perivenous extent of white matter lesions (WMLs) in multiple sclerosis (MS). We aimed to assess the discriminatory value of the "central vein sign" (CVS). In a lesion-based 3 T MRI study, 28 WMLs in 14 patients were prospectively included applying the following criteria: 1) at least one circumscribed lesion > 5 mm, 2) not more than eight non-confluent lesions > 3 mm. FLAIR images served as gold standard for the identification of WMLs which were classified as periventricular, subcortical, or infratentorial. Only defined WMLs with a maximum diameter of > 5 mm were correlated with their SWI equivalent for CVS evaluation. Results: Five patients fulfilled the revised McDonald criteria for MS and nine patients were given an alternative diagnosis with non-MS-WMLs most probably representing focal gliosis. A total of 28 lesions > 5 mm (19 MS-WMLs and 9 non-MS-WMLs) were detected. Consensus reading found a central vein in 16 out of 19 MS-WMLs (84%) and in one out of nine non-WMLs (11%), respectively. The CVS proved to be a highly significant discriminator (p < 0.001) between MS-WMLs and non-MS-WMLs with a sensitivity, specificity, positive and negative predictive values, and accuracy of 84%, 89%, 94%, 73%, and 86%, respectively. The frequency of CVS positive lesions was highest in the periventricular zone (7/10), even more markedly in MS-WMLs alone (6/7). Inter-rater agreement was good (kappa=0.77). Conclusion: Even though the CVS is not exclusively found in MS-WMLs, SWI may be a useful adjunct in patients with possible MS. Single-and multi-voxel proton spectroscopy in patients with pyogenic brain abscess P. The study was primarily designed to find the optimal dose range of BR14 to detect malignant focal liver lesions. Secondary objectives were the evaluation of the safety profile and comparison with contrast-enhanced MRI (CE MRI). Methods and Materials: 25 patients (9f, 16m, mean age: 66y) with known HCC or liver metastases were examined in three centres during a time period of three months. Each patient underwent a baseline and at least three contrast-enhanced US (CEUS) with ascending dose levels (0.25 ml, 1.0 ml, 4.0 ml) of BR14. CE MRI was done 4 weeks prior or post-study examination. Lesions were recorded in on a liver map, with respect to localisation, size and suggested lesion type. Examination quality was documented and safety parameters were assessed. Results: The number of lesions detected with BR14 CEUS increased with dose, while the number of missed lesions and the lesion size decreased. Despite the increasing contrast enhancement no other image quality parameter showed a substantial difference. No significant changes were found for the analysed safety parameters and no serious adverse events were reported. Conclusion: We finally conclude that the recommended dose level of BR14 is between 1.0 ml and 4.0 ml for which the lesion detection was comparable to the CE MRI. In addition, we found a higher number of especially small lesions with higher doses of BR14 which might be due to a higher sensitivity of CEUS for the detection of liver metastases. However, this is an interesting and debatable finding. Histopathological characteristics of the primary HCC and recurrence were obtained by a review of the pathologic reports. The association between the variations in histopathological and imaging characteristics of primary and recurrent HCC was estimated using linear regression analysis. The initial recurrence was extrahepatic in 14 (58.3%, lung, bone, lymph nodes, brain, spleen, adrenal), intrahepatic in 7 (29.2%) and both intrahepatic and extrahepatic (peritoneum, lung, bone, lymph nodes) in 3 (12.5%) patients. Of 14 patients with initial or late intrahepatic recurrence, 2 (14.3%) showed a variation in imaging characteristics between the primary HCC (hypervascular) and the recurrence (hypovascular), 1 (7.1%) showed a variation in histopathological char- During 2005-2011 588 patients with 1-3 HCCs were treated with radiofrequency ablation (alone or combined with ethanol injection) . Patients had complete ablated tumours at 1 mo. CT was followed-up serially, using alternated CEUS (one sulphur hexafluoride-based microbubbles injection per lobe) and CT every 3 months. The following patterns of recurrence were considered: A, enhancing tissue within the lesion; B, enhancing tissue adherent to the lesion; C, enhancing tissue within the same liver segment of the treated nodule; D, enhancing tissue within a different segment (progression Heidelberg/DE (gregor.pahn@med.uni-heidelberg.de) Purpose: Quantitative assessment of image quality and radiation exposure reduction potential of a next-generation solid-state MDCT detector with fully integrated readout electronics in comparison with its predecessor. Methods and Materials: Using standard CT image quality phantoms and an automated quantitative image quality analysis software developed in-house, image quality and radiation exposure (RE) of an MDCT system (Somatom Definition Flash, Siemens) either equipped with UFC™ or new "Stellar" detectors has been assessed for different combinations of acquisition and reconstruction parameters. Subsequently, measurements and analysis were repeated for "Stellar" detectors without altering parameters apart from noise-weighted reduction of tube currenttime product resulting in image noise levels equal to those achieved when using their predecessor. Results: Image noise of both detectors was comparable for small absorption crosssections (Øwater=24 cm) while being 18-35% lower for large ones (Øwater=40 cm) when using "Stellar" detectors. CT number stability and uniformity declined with increasing subject cross-section, particularly at 80 kVp, though not as much for "Stellar" detectors. When noise of "Stellar" acquisitions was increased to UFC™ levels, RE reduction of 28-54% was achieved. For the "Stellar" detector CNR was slightly higher (same RE) or slightly lower (reduced RE), while spatial resolution was always equal for both detectors (up to 20 lp/cm at MTF10%). Conclusion: Overall image quality improves when a next-generation MDCT detector is employed instead of using its predecessor. For acquisition settings intrinsically acteristics (from moderate to poor differentiation), but no association was found between imaging and histopathological variations. The most common pattern of recurrence was extrahepatic location, followed by intrahepatic recurrence and both intrahepatic and extrahepatic diffusion. Variations in dynamic-imaging characteristics of intrahepatic recurrence were not associated with variations in histopathological characteristics. Films strips were scanned before and after irradiation with the Epson Perfection V500 photo scanner in reflective mode. The reference dosimetry system was calibrated in terms of air kerma in air. The measured reflectance change is converted into air kerma using a calibration curve. Air kerma was converted into absorbed dose using the appropriate ratio of mass-energy absorption coefficients water-to-air for a given beam quality, defined by half-value layer following the AAPM TG-61 protocol. Results: Dose values for each of the five CTDI phantom film positions were obtained by averaging dose profiles from each film piece over the length of 10 cm, and were used to calculate weighted CTDIvol. The average difference for six scanners between calculated and listed CTDIvol was 3.9% with a maximum observed difference of 6.9%. Conclusion: In contrast to ionisation chamber measurement, the proposed method requires only a single exposure, does not need stem effect correction, and provides an acceptable accuracy in comparison to CT scanner listed CTDI values. Measured dose profiles allow for measurements of DLP and peak doses at the same time. associated with high image noise the new detector exhibits much lower noise levels, offering great potential for radiation exposure reduction without adversely affecting overall image quality. Munich/DE (zsuzsanna.deak@med.uni-muenchen.de) Purpose: To evaluate the dose reduction potential of HIR and IR in comparison with FBP. Methods and Materials: An anthropomorphic cardiac phantom (QRM Corp., Germany) was scanned using a 64-row MDCT scanner (CT 750HD; GE-Healthcare, USA). The phantom's calcification insert was replaced with a model simulating a stented aortic aneurysm with endoleak and intraluminal thrombus. Images were obtained at tube voltages of 120 kV, 100 kV and 80 kV using automated tube current modulation with incrementally increasing noise indices (NI=16, 25, 34, 43, 52, 61, 70) adjusted to a primary reconstruction slice thickness of 2.5 mm. After acquisition, images of 0.625 mm slice thickness were secondarily re-reconstructed with FBP, HIR (ASIR® with 50% blending, GE-Healthcare) and IR (Veo®, GE-Healthcare). Twenty-one radiologists blinded to image reconstruction methods independently analysed the detectability of simulated vascular pathologies (endoleaks < 1 cm² and intraluminal thrombus < 3 mm). Contrast-to-noise ratio was measured for the stented aorta. A two-by-two Purpose: To compare two low-dose scanning protocols, and to estimate effects on the signal, noise, effective radiation dose (ED), quality of acquired data. Methods and Materials: 90 patients were divided into three groups. The scanning protocol was 120 kVp 200 mAs in first group, 80 kVp 200 mAs in second group, and 120 kV 50 mAs in third group, special reconstruction algorithms have not been used. For quantitative and qualitative evaluation we used visual scores (1-3), mean arterial attenuation, noise, contrast-to-noise ratio (CNR) in three arterial segments and ED. Results: The BMI ranged from 21 to 38 kg/m2 and were not significantly different between groups (p=0.07, 0.614, 0.297, respectively). The mean intraarterial attenuation in 1, 2, 3 groups was 315±6 HU, 448±76 HU, 334±33 HU, respectively, but significantly higher in second group (p=0.0003). Noise in second group (64±20 HU) was significantly higher than that in third group (45±14 HU, p=0.0002), and first group (29±8.5 HU, p=0.0002). The CNR in second (6.64±2.3) and third (6.36±2.1) groups was significantly lower than that in first group (11.7, p=0.0001). Image quality was comparable between three techniques, except aorto-iliac segment in second group. Effective dose was 27.1±5.9mZv, 8.1±1.8mZv and 6.4±1.02mZv, respectively, differences were significant (p=0.0001). Conclusion: Average radiation dose reduction up to 77% was achieved using "80 kV" and "50 mAs" protocol providing sufficient image quality. Application of the 80 kV protocol in people with BMI> 30 is limited, especially in evaluation of aorto-iliac segment due to higher noise and attenuation levels. While at 50 mAs protocol such limitation is not observed. This allows to recommend it as the preferred protocol for low-dose runoff CTA in case of special reconstruction algorithms. Purpose: To assess the quality of CT images reconstructed with sinogram affirmed iterative reconstructions (SAFIRE) and comparing their performances with Iterative reconstructions in image space (IRIS) and standard filtered back projection (FBP) algorithms on a Siemens Somatom Definition Flash. Results were used to optimise a dual energy (DE) abdominal protocol. Methods and Materials: FBP, IRIS and the 5 strength levels in SAFIRE (S1-S5) reconstructions were characterised in contrast, noise and spatial resolution for medium-smooth filters using a tungsten wire in air, water and Catphan phantoms. Standard deviation (SD), contrast-to-noise ratios (CNR), noise power spectra (NPS), modulation transfer function (MTF), and the non-prewhitening matched filter signal-to-noise ratio (SNRNPW), a quasi-ideal observer metric in the frequency domain assumed to be the most reliable image quality reference, were calculated for all kernels and used for dose saving evaluations. Results: The highest CNR in DE protocol resulted with a composition factor of 0.6. Compared to FBP, the average SD reductions were 51±2% with SAFIRE S5 and 30±2% with IRIS kernels. A shift towards low frequencies in the NPS was found for all iterative filters, giving to images a different texture. Differences between MTF values were within 5% in all FBP-Iterative coupled filter comparisons. The optimal kernels, from SNRNPW analysis of abdominal protocol, resulted I31-S5 for SAFIRE and I-44 for IRIS with a potential dose reduction of 42% and 30%, respectively. Conclusion: Iterative reconstructions and DE acquisition strongly improve image quality reducing the noise and improving the contrast without affecting the spatial resolution. The impact of tube voltage, scan direction and beam collimation on the performance of automatic tube current modulation systems in paediatric and adult CT N. Buls 1 , J. Schoenaers 2 , G. Van Gompel 1 , K. Nieboer 1 , J. Purpose: To reduce the radiation dose exposure and contrast medium volume using low-kV CT angiography protocol (100 kV; 40 ml) in the evaluation of abdominal aorta, maintaining high diagnostic performance. A total of 60 patients with abdominal vascular disease were prospectively enrolled. All patients underwent 256MDCT scan examination of abdominal aorta (Brilliance iCT, Philips). 30 patients were scanned using lowdose radiation protocol (100 kV; automated tube current modulation) and ultralow-contrast volume (40 ml; 4 ml/s; 350 mgI/ml) and a control group of 30 patients underwent standard CT-angiography protocol (120 kV; automated tube current modulation) and standard contrast volume (120 mL). Density measurements were performed on abdominal aorta, renal arteries and common iliac arteries. The radiation dose exposure (dose length product, DLP), the intravessels density and the signal-to-noise ratio (SNR) were calculated, compared and statistically analysed. Results: All exams were considered diagnostic, allowing the correct visualisation of main aortic branch and vascular wall. Higher density measurements were obtained in low-kV protocol: mean attenuation value of abdominal aorta 343 HU, renal arteries 331 HU and common iliac arteries; in comparison to control group: mean value of abdominal aorta 319 HU, renal arteries 294 HU and common iliac arteries 323 HU. A reduction of 65% (p < 0.05) of radiation dose exposure in low-kV protocol (335 DLP; 5.8 CTDIvol) was obtained among control group (973 DLP; 19.4 CTDIvol). Conclusion: Low kV protocol and ultra-low contrast medium volume (40 mL) reduce the radiation exposure (over 65%) and the renal damage, allowing a relevant reduction of contrast material volume, enabling to evaluate more easily young patients or patients with renal failure. An international multi-centre comparison of the non-contrast MR angiography technique time-spatial labelling inversion pulse (time-SLIP) against contrast-enhanced CT angiography for assessing renal artery stenosis: the renal artery contrast-free trial ( (t.vogl@em.uni-frankfurt.de) Purpose: To compare contrast-enhanced magnetic resonance angiography (MRA) with conventional digital subtraction angiography (DSA) for detecting stenoses and planning of therapy in patients with peripheral artery occlusion disease (PAOD). In this retrospective study, 71 patients (20 women/51 men; mean: 68 years) with established PAOD underwent both imaging modalities in a maximum interval of 40 days. DSA was the standard of reference. The pelvic and leg arteries were divided into 31 anatomic segments, which were graded on a scale from 1 to 4 (1=no stenosis, 2=stenoses < 70%, 3=stenoses ³70%, 4=occlusion). The pelvic and leg vessel systems were categorised with the TASC II-score into five grades (none, TASC-A, TASC-B, TASC-C and TASC-D) for detecting whether the therapeutic consequences would be the same for both imaging modalities. Iodine load reduction in CT aorta angiography with gemstone spectral imaging: comparison with standard CT aorta angiography X. Luo, J. Wu, J. Sun, M. Chen; Yangzhou/ CN (luoxianfu@gmail.com) Purpose: To compare quantitative and subjective image quality between computed tomographic aorta angiography (CTAA) with a gemstone spectral imaging (GSI) technique with reduced iodine load and standard CTAA. Methods and Materials: 86 patients underwent CT scanning on HDCT (Discovery CT750 HD, GE Healthcare). All cases were randomised into two groups: standard CTAA (100-120 kVp) with 500 mg/kg per body weight of iodine (n=46) and GSI scanning CTAA (image reconstruction at 50 keV) with the same injection volume as in the standard protocol but composed of contrast medium and saline in a 1:1.5 fashion (n=40). Signal intensity and noise of aorta were measured; signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. A five-point scale was used to subjectively evaluate vascular enhancement and image noise. Results: Compared with standard CTAA, GSI CTAA demonstrated higher signal intensity in all aorta arteries (all P < 0.05), inferior noise only in segmental arteries (P < 0.05), higher SNR and CNR (both P < 0.05), and compatible effective dose (P > 0.05). The five-point score was higher in the standard CTAA protocol (P < 0.05). The inter-reader agreement regarding the dichotomized diagnostic versus nondiagnostic scale was similar (P > 0.05) between two groups. Conclusion: GSI CTAA with image reconstruction at 50 kev allows a significant reduction of 60% iodine load while improving intravascular signal intensity, maintaining SNR and with comparable radiation dose. >/=70% and CTA 0.05). Post-interventional AVR did not correlate with pre-procedural measured AS and AV (both p> 0.05). Patients with post-procedural AVR showed no significant differences in AS and AV than patients without evidence of AVR after TAVI ( Thursday target noise SD12.5 and FBP reconstruction) and referred to follow-up chest CT within two months were enrolled. AEC (SD25) integrated with AIDR3D was used in follow-up chest CT protocol (group B), the raw data of which were reconstructed again with FBP (group C). The max/min mAs of each subject and their correlation with BMI were investigated to validate whether system could personalise tailor tube current. The chest images were divided into upper, middle and lower parts which were evaluated separately by two radiologists with 3-point scale (3-good, 2-acceptable, 1-poor). Image noise was measured in these parts with 8-mm diameter ROI placed on specific anatomic structures. Effective dose (ED) was compared. . MPR and 3D reconstruction images were created, and reviewed by two experienced radiologists with blinded, who measured the tracheal lumen to determine the presence of central airways narrowing. The 3D reconstruction of confidence was graded on a 4-point scale from 0 (no confidence) to 3 (highest of confidence. The MPR noise was assessed by measuring the SD of the pre-sternal soft tissue. The DLP was used to compare radiation doses. Results: The MPR image noise was ranked higher for CT images of 80 KV protocol than 100 KV protocol. There was no significant difference in confidence between 80KV and 100 KV protocol (P > 0.05). Excessive central airway collapse (reduction > 30%) was seen in 3 patients with tracheomalacia and remaining 13 subjects had centre airway stenosis. DLP of 80KV protocol was 244.9 mGy.cm and 100KV protocol was 539.8 mGy.cm. The 640-slice dynamic volume CT is a promising method for diagnosing central airway narrowing. The 80KV protocol performs as well as the 100KV protocol for the 4D dynamic imaging in small BMI objects. Purpose: The purpose of this study was to examine the influence of different arm positioning on automatic tube current modulation of multi-slice CT on chest image quality and radiation dosage. Methods and Materials: Sixty patients underwent scanning by using Care Dose 4D thorax CT protocol in which both arms were raised above the shoulder region using standard-position (Group 1) and postural manoeuver (Group 2), respectively. Objective and subjective image quality was assessed. Individual recorded the CTDIV values and the tube current-time product per exposed section. Effective radiation dose was calculated. Results: Compared with the image quality in the standard-position group, the image quality in the postural manoeuver group was decreased on subjective image quality but within acceptable diagnostic limits. The average effective dose in the postural manoeuver group was 3.37 mSv; the dose in the standard-position was 17% lower than this. Conclusion: Both arms were raised above the shoulder region scanning using Care Dose 4D thorax CT protocol can reduce the overall dosage to patients and the image quality without adverse influences, and may be more feasible in clinical practice. The effectiveness of lead apron for radiation protection in CT N. Weber, P. Monnin, C. Elandoy, S. Ding; Lausanne/CH (nicolas.weber@hesav.ch) Purpose: To determine the effectiveness of lead shielding for radiation protection in CT. Methods and Materials: Three 32-cm diameter CTDI (PMMA) phantoms, of 15 cm long, placed side by side, were scanned over a length of 28 cm with a GE 64 CT scanner. Absorbed dose was estimated with thermoluminescent dosimeters positioned in the middle, and at two levels in periphery of the phantom (1 cm inside): top and bottom. Additionally, the dose was measured on the surface of the phantom ("skin dose"). TLD were placed over a length of 28.5 cm, with 14.5 cm in the scatter field. Three acquisitions were performed: 1) without lead apron, 2) with a lead apron at 0 cm from the edge of the primary field and 3) with a lead apron at 2.5 cm. Results: In scattered radiation, no significant difference of dose was found between without shielding and with the apron at 0 cm, in the middle of the phantom. However, in the presence of the apron the dose is lowered by as much as 12% at the bottom of the phantom, whereas the skin dose is increased by 10% (tunnel effect). This indicates that the scanner A retrospective study was conducted in two radiology departments from public hospitals using a sample of 535 patients under 15 years submitted to head CT examinations between 2008 and 2011, performed with different equipments: Somatom Emotion 2 (n=100), Somatom Emotion 6 (n=250) and Somatom Emotion 16 (n=185). The influence of patient age and cephalic perimeter were considered. Multiple data analysis was used in order to assess radiation dose levels and the concordance of these with diagnostic reference levels. The results were obtained for four different paediatric groups, divided according to patient age: less than 1 year; 1 to 5 years; 6 to 10 years and 11 to 15 years. The mean values obtained of dose length-product from some groups are lower than the diagnostic reference levels (720 mGy.cm from 6 to 10 years and 807 mGy.cm from 11 to 15 years). However, until 5 years the values are higher than the recommendations (569 mGy.cm for less than 1 year and 590 mGy.cm from 1 to 5 years). Conclusion: This work identifies possible gaps and all possible methods should be applied to reduce the radiation dose provided without deteriorating image quality. A set of recommendations are needed to optimise the radiation dose since the children have a superior radiosensitivity. Dose values in eye lens in paediatric brain computed tomography: influence of different protocols C. Carriço 1 , M. Inácio 1 , A. Kristiansen 2 , M. Larsen 2 , J. Santos 1 , S. Holm 2 , G. Paulo 1 ; 1 Coimbra/PT, 2 Odense/DK (catarina.carrico@hotmail.com) Purpose: The number of head computed tomography (CT) examinations in paediatrics had an exponential increase. Taking into account the highest radiosensitive of children tissues and organs, radiology departments should permanently optimise CT protocols in order to minimize exposure, especially to more radiosensitive Thursday body mask is classified into 4 classes (fat, water, air, and outliers) by a multivariate Gaussian intensity model, regularized by a Markov random field. To increase robustness to image variability, the statistical model parameters are automatically updated with the EM algorithm. The air voxels are rejected from the mask and the adipose tissue segmentation is refined using a new 3-class Gaussian intensity model. To separate SAT from VAT, an intra-abdominal mask is created by calculating the convex hull around the water tissue (water fraction of at least 50%). The adipose tissue quantification is, even under heavy motion, visually satisfactory. It is, moreover, highly consistent over the two datasets of each subject, as demonstrated by the high ICC (r=0.997) and the small difference in fat, SAT, and VAT percentage of total body volume of 0.26%, 0.14%, and 0.12%, respectively. Conclusion: An automatic adipose tissue quantification method based on spatially regularized multivariate Gaussian mixture models is demonstrated to provide consistent measurements for SAT and VAT. Computational texture analysis in interstitial lung disease: comparison of descriptors and classification accuracy J. Ofner 1 , C. Purpose: To evaluate and compare sequential CT to spiral CT examinations of the brain in terms of radiation dose and image quality. The study was carried out prospectively on 40 patients referred for brain CT. Radiation dose and image quality data were gathered from an equal number of CT examinations performed with either sequential (n=20) or spiral (n=20) techniques. Radiation dose data in terms of CTDIvol and DLP were recorded by the scanning radiographers at the end of each examination. A CT brain image evaluation set was compiled which was evaluated by four radiologists. The radiologists evaluated the quality of the images by visually grading the reproduction of anatomical structures as outlined in EUR 16262: European guidelines on quality criteria for CT. Results: Mean CTDIvol and DLP readings were significantly higher (p < 0.05) for sequential scans over spiral scans (CTDIvol: 22.06 mGy vs. 14.94 mGy and DLP: 304.60 mGycm vs. 229.10 mGycm). The mean image quality grading scores for all criteria for the sequential technique were significantly (p < 0.05) higher than those obtained by the spiral technique. Conclusion: Spiral acquired CT brain images have lower radiation doses. The quality of the images produced using this technique, however, produces images of a lower quality to those obtained using the sequential technique. Further research is recommended investigating whether the level of image quality produced by the spiral technique is sufficient for diagnosis in order for patients to benefit from associated radiation dose reductions. termined the number of alerts triggered, based on the currently used, exclusively study description-based threshold method. The default setting of this threshold is twice the median for each separate descriptor. Then, logical combinations of study description and protocol were made and linked by a RSNA Radlex elements, for a total of 62% of all examinations. The mapped data sets were then used to determine the number of alerts triggered when using a threshold method based on a combination of study description and acquisition protocol. The impact of both strategies on relevant dose information was assessed. Results: Considering only the relevantly mapped scans, we found a 51% decrease, from 959 to 466 alerts, using the Radlex-based alert triggering. Of these, 23 (5%) were not previously reported by the old method. The new alerts could all be attributed to patient or examination-related factors. Of the 470 alerts (49%) that were no longer reported, none were found to have any clinical relevance. The combination of study description and acquisition protocol in the threshold method for CT dose measurements helps to decrease the number of alerts, while maintaining patient safety. Purpose: To optimise CT protocols and parameter settings, by comparing the radiation dose between 2 different CT scanners of the same type. Methods and Materials: Using dedicated software (DoseWatch®), dose information from CT examinations performed on two 64-slice LightSpeed VCT scanners over an 7-month period was prospectively evaluated. We compared the administered radiation doses for 61 equivalent acquisition protocols on the 2 machines, and identified acquisition protocols in which there was a significant dose variation. For these protocols, we performed a rigorous imaging parameter check, including comparison of the number of examinations, acquisition types, number of irradiation events, mA, KVp, scanning length, exposure time and pitch factor. These data were then linked to the protocol setup. Results: We found significant parameter variations in 5 out of 61 CT acquisition protocols. In 4 cases, the variations could not be attributed to a difference in the acquisition protocol set-up, and a thorough inspection did not lead to any improvement. For 1 acquisition protocol (helical skull), we found that the noise index was erroneously configured on one of the CT machines. After correction of this parameter, the median dose length product (DLP) on this machine was reduced from 771 mGy.cm to 446 mGy.cm (42% decrease), based on measurements during 2 months prior to correction (148 cases) and 5 months after correction (364 cases). The use of a patient dose managing system for CT can identify suboptimal parameter settings, and helps to significantly reduce the radiation dose without loss of relevant diagnostic information. IT (marco.moschetta@gmail.com) Purpose: To assess the reliability of 3D analysis CT software in determining urinary stones volume and density. Methods and Materials: CT images of 140 patients for a total of 219 urinary stones (116 calyceal, 22 pelvic, 81 ureteral) were evaluated. All exams were performed using a 320 MDCT with a low dose protocol and without injection of contrast material. CT scans were independently evaluated by two expert radiologists. For each stone, volumetric [SV (stone volume) = l (length) x w (width) x t (thickness) x π x 0.52 ] and densitometric [selecting a ROI on axial plane] measurements were calculated. The obtained data were then compared with the measurements performed by the 3D analysis CT software (Vitrea fX 2.1). Differences between the two systems were evaluated by the analysis of variance (Anova) test. The interobserver agreement was calculated using the Cohen's kappa (k) test. The volumetric and densitometric measurements of urinary stones obtained without 3D analysis software showed a lower interobserver agreement (k = 0.54) than that resulting from the use of the software (k = 0.98). Statistical significant differences were found between volumetric and densitometric measurements as performed with and without the 3D software for each urinary stone (p < 0.05). Conclusion: Volumetric and densitometric evaluation of the urinary stones provided by 3D analysis software is reliable and reproducible and could significantly influence the therapeutic choices. The 3DSlicer open-source platform for segmentation, registration, quantitative imaging and 3D visualisation of biomedical image data S. Pujol 1 , S. Pieper 2 , R. . Overall image quality, identifiability of vessels and homogeneity of liver parenchyma were graded by two experienced radiologists in consensus using a 5-point rating scale with a true non-contrast CT (tNC) scan as standard of reference (1=no difference; 2=minimal, non-relevant difference; 3=visible but diagnostically irrelevant difference; 4=relevant difference; 5=obvious difference). Image noise was measured in liver parenchyma, retroperitoneal fat and aortic lumen. Wilcoxon signed-rank non-parametric test was used to assess statistical significance. The nVNC was superior compared to the standard VNC regarding overall image quality and identifiability of vessels (2.4 vs. 3.2/p < 0.001 and 1.4 vs. 1.9/p < 0.001), whereas no significant difference was observed concerning the homogeneity of the liver parenchyma (nVNC: 2.5/sVNC 2.4). There was no significant difference regarding image noise with an average value of 7.5 HU (nVNC) and 7.4 HU (sVNC), respectively, compared to 9.8 HU (tNC). The new algorithm provides a better image quality and an improved assessment of vessels and small structures. The nVNC images represent adequate substitutes for TNC images, rendering an omission of non-contrast acquisitions feasible, corresponding to a substantial dose reduction. Image quality of monoenergetic low-keV datasets for lower extremity dual-energy CT angiography S. Sudarski, D. Schneider, P. Apfaltrer, S.O. Schönberg, T. Henzler; Mannheim/ DE (sonja_sudarski@gmx.de) Purpose: To compare image quality of conventional 120-keV polyenergetic images (PEIs) and monoenergetic images (MEIs) for dual-energy CT angiography (DE-CTA) datasets of the lower extremity. We retrospectively evaluated DE-CTA datasets obtained from 18 patients (13 men, 67±10 years). MEIs were calculated in 10-keV intervals from 120 to 40 keV using the 80-and 140-keV image data. Attenuation and image noise were measured in the external iliac, femoral, popliteal and one lower leg artery. Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were calculated for each vessel. Differences in these parameters were compared between the different monoenergetic datasets. The two best MEIs were compared to 120-keV-PEIs. Results: SNR and CNR of 70-and 60-keV MEIs were highest when compared to other low-keV MEIs. In 70-keV MEIs, CNR in external iliac, femoral and popliteal arteries was higher compared to PEIs (+29%, +19% and +12%; p < 0.05), while CNR did not change in lower leg arteries (p> 0.05). SNR in external iliac and lower leg arteries was equal in 70-keV MEIs and PEIs, while in femoral and popliteal arteries it was lower (-9%, -10%; p < 0.05). 60-keV MEIs showed a higher CNR in lower leg arteries compared to PEIs (+17%; p < 0.05), while SNR did not differ (p> 0.05). In the other three arteries, 60-keV MEIs showed significantly not only higher CNR but also lower SNR. Purpose: Persistent sub-centimetre GGO are pre-malignant. HRCT improves detection of small nodules and low dose CT (LDCT) reduces patient exposure but both decrease CNR essential for characterisation of small GGO. We investigate the use of adaptive iterative dose reduction (AIDR) in low dose HRCT (LD-HRCT) for diagnosis of small GGO. Methods and Materials: LDCT (120 kV, 25 mAs, 64 x 0.5 mm) was used in 3 stages: 1) computer-simulated lung nodules 5, 8 and 10 mm spheres each of CT# 100, -630 and -800 HU; 2) identical synthetic nodules, placed in an anthropomorphic chest phantom and 3) 22 in vivo pulmonary nodules (13 GGO, 9 solid); 5.1 mm diameter (4.0-6.9), mean CT# -327 HU (8 to -738). Raw data reconstructions are as follows (slice thickness/overlap mm): 0.5/0.5, 1/1, 2/1, 2/2, 3/1, 4/2, 4/4, 5/2.5 and 5/5 with FBP. In vivo images were also reconstructed with AIDR. CT# and CNR were determined for each protocol. Results: CT# accuracy decreases with increased slice thickness for all nodules: 5/5 reconstructions decrease CT# > -400 HU for 5 mm solid (+100 HU) nodules and ~ -130 HU for 5 mm GGO (-630 HU and -800 HU), Spearman's coefficient = -1.0, p < 0.005. HRCT (< 3.0/1.5 mm) has accurate nodule CT# (error< 10% Purpose: To investigate whether optimisation of volume-doubling time (VDT) cutoff for fast-growing nodules in a lung cancer screening trial can improve accuracy of lung cancer diagnosis. Methods and Materials: All subjects underwent at least two low-dose computed tomography (CT) scans during the baseline-round screening and regular secondround screening in year 2 of the NELSON lung cancer screening study and were referred to a pulmonologist because of a solid nodule with volume ³50 mm 3 and VDT < 400 days. Histology was the reference for diagnosis, or, to confirm benignity, stability of the nodule volume on subsequent CT scans for at least two years after referral to a pulmonologist. Nodule volume and VDT were semi-automatically calculated by software. Reduction of false-positive rate was evaluated at maintained sensitivity for lung cancer diagnosis with the VDT cut-off of 400 days as reference. Results: 68 fast-growing nodules were included (61 individuals), of which 27 nodules (40%) were malignant. Mean follow-up of non-resected benign nodules was 4.4 (range 2.7-5.7) years. The optimal VDT cut-off for the 3-month follow-up CT in the baseline round was 232 days. Using this cut-off, false-positive referrals reduced by 33% (20 versus 30 false-positive referrals). For the regular secondround screening, VDTs varied more among malignant nodules, precluding lowering of the VDT cut-off of 400 days. Conclusion: Lowering the VDT cut-off of the 3-month follow-up CT in baseline lung cancer screening from 400 to 232 days may reduce false-positive referrals, without apparent loss in sensitivity. MIA, invasive adenocarcinoma, and the extents of invasive carcinoma component were quantified. Association between imaging parameters and pathologic classification was examined. Results: 177 patients (98%) were pathologic stage 1 A, and 2 were 1B and the other one was 2 A. Of all 190 tumours, 38 were AIS (20%), 56 were MIA (29%), and 96 were invasive adenocarcinoma (51%). Based on univariate analysis, tumour size in lung setting, uniformity, and entropy were able to significantly separate tumours according to pathologic classification, whereas TDR, volume, mass, or SUVmax were not. On multivariate analysis, uniformity and entropy were remained as independent factors to stratify the pathologic subgroups of patients (odds ratio [OR] = 0.001, P =.007, and OR = 2.4, P =.01, respectively). Conclusion: Texture parameters on CT imaging metrics, reflecting tumour heterogeneity, appear to help stratify pure GGN lung adenocarcinoma. Non-solid, part-solid or solid? Classification of pulmonary nodules in thoracic CT by radiologists and a computer-aided diagnosis system C. Purpose: Classifying pulmonary nodules into solid, part-solid and non-solid is crucial for patient management. A computer algorithm is compared to a radiologist on a large data set obtained from a multi-center lung cancer screening trial. Methods and Materials: Low-dose chest CT scans (16x0.75 mm, 120-140 kVp, 30 mAs) with part-solid, non-solid, and solid nodules with a diameter between 7 and 30 mm were randomly selected from two sites participating in the Dutch-Belgian NELSON lung cancer screening trial. The set contained 137 scans, including 50 part-solid, 50 non-solid and 52 solid nodules. The nodule-type recorded in the screening database was used as a reference standard. An automated classification system for characterisation of nodules was designed using morphometric features. The accuracy of the computer algorithm was evaluated in three ways: classifying nodules (1) as solid or subsolid, (2) as solid, part-solid or non-solid, and, (3) for the subsolid lesions only, as part-solid or non-solid. An experienced thoracic radiologist independently performed the same classification. The accuracy of the automated system to differentiate between solid and subsolid nodules was 0.88, compared to 0.95 for the radiologist. The computer classified the nodules as solid, part-solid or non-solid with an accuracy of 0.72 versus 0.80 for the radiologist. The software reached an accuracy of 0.71 in differentiating part-solid from non-solid nodules, where the radiologist had an accuracy of 0.77. Conclusion: A novel automated characterisation tool for pulmonary nodules shows promising performance and could aid radiologists in selecting the appropriate workup for pulmonary nodules. (19), additional to bled aneurysm (9) and additional coiling (21). Aneurysms ranged in maximal size between 2 and 30 mm (mean/median 9 mm). Aneurysms were located in the cavernous sinus (n=14), supraclinoid internal carotid artery (n=33), anterior communicating artery (n=3), middle cerebral artery (n=2), pericallosal artery (n=2) and posterior circulation (n=17). Patients were preloaded with aspirin and clopidogrel (multiplate test control). Clinical and angiographic follow-up was done at 3-to 12-month intervals after treatment. Results: Single stents were placed in 49 cases, 2 stents in 12 and flow-diverter stents in 10. In 14 cases no additional coil aneurysm occlusion was performed. Seventeen procedural complications occurred (24%): 3 thrombo-embolic, 5 in-stent thrombosis, 3 haemorrhages, 3 side-branch occlusions and 3 technical device problems. Most had no clinical sequel, but 2 patients died (3%) and 5 patients had permanent neurological deficit (7%). Five aneurysms (7%) needed second additional stenting during follow-up. Mean follow-up was 9 months (range 0-39 months). Conclusion: Endovascular intracranial aneurysm occlusion with stent assistance is a delicate procedure with a higher complication rate compared to regular coil occlusion. However, this technique is useful in complex otherwise difficult or untreatable intracranial aneurysms. In-stent restenosis occurred in 9/683 cases (1.3%) and solved with angioplasty in 2/9 cases (22%) or re-stenting in 7/9 (78%). Primary patency rate was 98.7%; secondary patency rate 100%. Neurological events occurred in 3.2% of cases. Results were analysed correlating neurological complications with the operator's experience, plaque morphology and patient's age. Neurological disorders were 1.9 % in asymptomatic patients and 4.5% in symptomatic ones (p=0.001) and they proved to be higher in older patients (> 80y) 6.4% vs 2.7% of patients < 80 years (p < 0.05). The overall neurological adverse events were 6.1% in the presence of complex plaque morphology and 1.0% in case of stable plaques (p < 0.001). Friday within 3 months after the procedure. A total of 91 high signal lesions on DWI were serially numbered and the signal change on conventional MRI in the follow-up was evaluated. The quantitative parameters on DWI (location, volume and value of apparent diffusion coefficient: ADC) for each lesion were measured. We used Fisher exact test and the Mann-Whitney U test to compare differences between two groups; statistical significance was assigned when p < 0.05. Results: There was statistically significant difference in the presence of DWI lesions (multiple: 65% versus single: 100%, p=0.03). In each lesion, the volume was significantly small (0.074±0.019 cm 3 versus 0.149±0.113 cm 3 , p=0.009) and the permanent signal change was less observed in multiple antiplatelets use (5.2% versus 24.5%, p=0.02). There was negative correlation between the volume and the value of ADC (r=-0.48, p <.0001). Conclusion: Periprocedural use of multiple antiplatelet agents is expected to reduce the volume of thromboembolism and permanent signal change in the follow-up. Purpose: The treatment of vertebral split fractures remains controversial, consisting of either corset or internal fixation. The aim of this study was to evaluate CT-and fluoroscopy-guided percutaneous vertebroplasty in the management of vertebral split fractures. Methods and Materials: Institutional Review Board approval and informed consent were obtained for this study. Sixty-two consecutive adult patients who had posttraumatic vertebral split fractures (A2 according to the AO classification) without neurological symptoms were prospectively treated by percutaneous vertebroplasty. All these procedures were performed by an interventional radiologist under computed tomography (CT) and fluoroscopy guidance using only local anaesthesia. Postoperative outcome was assessed using the visual analogue scale (VAS) and Oswestry disability index (ODI) scores. Results: Vertebroplasty was performed on thoracic and lumbar vertebrae. The filling of the vertebral body was satisfactory in 100% of the patients, with seven discal cement leakages (14%). The mean VAS measurements ± standard deviation (SD) significantly decreased from 7.9 ± 1.5 preoperatively to 3.3 ± 2.1 at 1 day, 2.2 ± 2.0 at 1 month, and 1.8 ± 1.4 at 6 months (P < 0.001). The mean ODI scores ± SD had also a significant improvement: 62.3 ± 17.2 preoperatively and 15.1 ± 6.0 at the 6-month follow-up (P < 0.001). Radiological union was observed within the 6 months following vertebroplasty in all the cases. The results of our study showed that type A2 vertebral fractures could be successfully treated by CT-and fluoroscopy-guided percutaneous vertebroplasty with an excellent functional recovery. Long-term results of microsurgical and endovascular therapy of intracranial aneurysms in patients following subarachnoid haemorrhage K. Bojanowski 1 , J. Baron 2 , B. Kostkiewicz 1 , M. Zawadzki 1 , J. Walecki 1 ; 1 Warsaw/PL, 2 Katowice/PL (jerzy.walecki@cskmswia.pl) Purpose: The aim of this paper was to evaluate long-term clinical outcomes and radiologic findings in patients following microsurgical treatment and endovascular embolisation of intracranial aneurysms. Methods and Materials: A total of 66 subjects aged 20 -75 (42 women and 24 men) were evaluated. Patients were divided into two groups according to the type of procedure they underwent: 36 patients had open surgery and 30 patients had undergone endovascular embolisation. The assessment was performed from 6 months to 4 years after treatment. All patients underwent a follow-up cerebral arteriography and clinical evaluation. Results: A total occlusion or a neck remnant was discovered in a majority of patients following microsurgical procedures and endovascular treatment (94% and 3% in contrast to 87% and 7%, respectively). No recurrent aneurysms were revealed. The Mann-Whitney U test did not reveal any statistical significance in long-term treatment results regarding self-reliance (p-value=0.2). The amount of blood extravasated following the rupture of an aneurysm was a significant independent factor influencing the clinical outcome and determined the long-term results in both groups (p-value< 0.05). A correlation between a patient's age and the clinical outcome following a microsurgical procedure was proved. The outcome was better in younger patients (p-value< 0.05). This was not observed in patients after endovascular treatment. Conclusion: Microsurgical and endovascular therapy are comparable methods for treating cerebral aneurysms; however, embolisation is correlated with a higher rate of complications in elderly patients. The final clinical outcome depends on the amount of extravasated blood following a subarachnoid haemorrhage. Embolisation of cerebral aneurysms with hydrogel-coated coils: systematic review and meta-analysis A. Pałys, Z. Serafin, W. Lasek; Bydgoszcz/PL (serafin@cm.umk.pl) Purpose: Hydrogel-coated coils for endovascular treatment of cerebral aneurysms were developed to reduce the risk of aneurysm recurrence and the rate of retreatment. The aim of this review was to verify the efficacy and safety of hydrogel-coated coils. Methods and Materials: A literature search was performed by two independent researches for papers published up to August 2012 on follow-up results of intracranial aneurysm embolisation with hydrogel-coated coils. Analysis included aneurysm presentation at follow-up compared to initial treatment result, the rate of rebleeding and retreatment, and specific complications. Pooled rates of major recurrences and total recurrences were calculated. Results: Of 41 articles on the use of hydrogel-coated coils for embolisation of cerebral aneurysms, 13 (1575 aneurysms) were included. Significant heterogeneity was found regarding patients populations, methods of aneurysm coiling, follow-up schedules, and recurrence definitions. A cumulative follow-up rate was 76% (95% CI, 74-78%, range 51-100%). Pooled major recurrence rate was 13% (95% CI, 11-15%, range 2-27%) and pooled total recurrence rate was 17% (95% CI, 15-19%, range 3-29%). Control groups consisting of aneurysms treated with bare platinum coils were analysed in only in four articles (436 aneurysms). Pooled major recurrence rate for bare platinum coils was 33% (95% CI, 28-38%) and was significantly higher than this for hydrogel-coated coils. Conclusion: Embolisation of cerebral aneurysms with hydrogel-coated coils results in lower rate of major recurrence, than with bare platinum coils. More high-quality standardised prospective studies are needed to define specific indications for the use of hydrogel-coated coils. Effect of antiplatelet therapy on radiographic outcome of positivity on diffusion-weighted imaging in elective endovascular coiling of unruptured cerebral aneurysm T. . 12 males (n=11) were followed retrospectively over 9 months; 8 males (n=8) were followed prospectively over 12 weeks. The diagnosis of PT was confirmed with ultrasound and power Doppler (average thickness of prospective subjects 10.3 mm, average neovascularisation 3.8 on modified Ohberg scale). All subjects were injected under real-time ultrasound guidance with 10 ml of 0.5% Marcaine mixed with 25 mg hydrocortisone followed by a mean of 30 ml normal saline at the interface between the PT and Hoffa's body, adjacent to the area of neovascularisation. The same supervised rehabilitation programme was followed by all patients. The VISA-P questionnaire was administered for pre-injection severity and at follow-up. Results: There was instant resolution of neovascularisation in all subjects. The VISA-P score statistically significantly improved from a mean of 45.5 to 64.0 for (p < 0.01), which is likely to be clinically significant. The retrospective data increased by 19.9 points compared to 16.4 in the prospective subjects followed over a shorter time period. Over 60% of the prospective subjects agreed/strongly agreed that their symptoms/strength had improved, with over 33% returning to their required level of sport within 12 weeks. Purpose: Our aim was to investigate the potential impact of visceral fat assessment by DXA in the clinical management of patients submitted to different therapeutic programs for obesity. We prospectively recruited 169 patients affected by obesity and submitted to medical and/or surgical treatment. Body mass index (BMI) and body composition were analyzed with anthropometric and whole-body DXA evaluations simultaneously performed at baseline and after one year. A new software available to estimate android visceral fat was applied to last-generation DXA equipment. Results: Ninety-one patients ruled out the study. Among patients ending the follow-up period (28-males, 50-females, 53.4±13.0-year-old, 40.5±9.1-Kg/m2) BMI decreased in 69/78-88.5% controls, while regained in 9/78-11.5%. An opposite trend between BMI and total fat mass/non-bone lean mass (TFM/TLM), android ratio (AFM/ALM), and android visceral/subcutaneous fat (V/S) was found in 7/78-9.0%, 11/78-14.1% and 31/78-39.7%, respectively. BMI was significantly correlated with TFM/TLM and AFM/ALM (r=0.717 and 0.713 respectively), while it was far from a statistically significant connection with V/S (r=0.011, p=0.896). Although slightly better correlations were demonstrated between TFM/TLM (and AFM/ALM) and V/S, these were extremely low (r=0.146, p=0.061 Purpose: To prospectively evaluate dual gradient-echo MRI with dixon-based generation of fat-/water-images (MRIDIXON) for quantification of the muscle-fat content (MFC) in-vitro and in patients with achillodynia compared to asymptomatic volunteers. Methods and Materials: MRIDIXON was used to measure the MFC of 15 phantoms containing titrated mixtures of organic muscle/fat from 0-100% as well as of the gastrocnemius (DixonGASTRO) and tibialis anterior (DixonTIBIALIS) muscles in 30 patients (13 women; mean age, 57±15 years) with achillodynia and in 20 matched asymptomatic volunteers (10 women; mean age, 30±14 years) at 1.5 T. Accuracy of MRIDIXON in quantification of MFC was assessed in-vitro as well as in-vivo using single-voxel MR-spectroscopy (MRS) as the standard of reference. DixonGASTRO and DixonTIBIALIS were related to visual grading of the MFC (grades 0-4) in both muscles (VisualGASTRO and VisualTIBIALIS). Results: Correlation of MFC derived from MRIDIXON, phantoms and MRS was excellent with correlation coefficient (R 2 ) ranging from 0.93 to 0.99 and mean measurement bias ranging from -0.1 to +0.8%. Mean DixonGASTRO/DixonTIBIALIS was 7.0±4.7/4.9±2.3 in patients and 3.6±0.7/3.6±0.5 in volunteers. VisualGASTRO/ VisualTIBIALIS ranged from 0 to 2/0 to 3 and 0 to 1/0 to 1, respectively. No significant difference was seen for DixonTIBIALIS between patients and volunteers (p=.07), whereas DixonGASTRO was significantly higher in patients (p <.01). Both, Visual-GASTRO and VisualTIBIALIS did not differ in patients and volunteers (all, p>.05). Conclusion: MRIDIXON allows for accurate quantification of MFC and demonstrates a significantly higher fat content in the gastrocnemius muscle in patients suffering of achillodynia than in asymptomatic volunteers, outer performing visual assessment of MFC. and disappeared after more than 12 months. The unloading-findings were more severe at the patella and femur than at the tibia (p < 0.001). High scores of severity were associated with confluent and patchy patterns (SCR=0.923, p < 0.01 and KT= 0.877 p < 0.01). Conclusion: Bone marrow changes at the knee related to disuse are most prominent 2-6 months following unloading when both patchy and confluent hyperintense patterns are present. Manifestations of unloading are most prevalent within the patella and the femur and associated with increased vascularity. Methods and Materials: From whole body 18 F-FDG PET/CT datasets including a dedicated head and neck investigation protocol of 40 consecutive patients (mean age: 61 ± 9 years) with histopathologically proven pharyngeal and laryngeal malignancies virtual 3D 18 F-FDG PET/CT panendoscopies were reconstructed using an investigational software application. The feasibility to completely assess specific spaces of the upper airways by a virtual "fly-through" and to detect primary tumours was tested; the time for an automated segmentation of the virtual 18 F-FDG PET/CT panendoscopies was measured. The nasopharynx, oropharynx, laryngopharynx, epiglottis, subglottis and the tracheobronchial tree were accessible in all 40, the laryngopharynx, aryepiglottical folds, piriform sinus, glottis, and oral cavity in 37, 37, 37, 33 and 16 patients, respectively. In all 12 patients with restricted fiberoptical evaluation due to a primarily intubation the subglottical space was entirely accessible via virtual panendoscopy. The primary tumour was depicted in 36/40 patients (90%). The mean processing time for virtual 18 F-FDG PET/CT panendoscopies was 145 ± 98s. Conclusion: Virtual 18 F-FDG PET/CT panendoscopy of the upper airways is technically feasible and can detect pharyngeal and laryngeal malignancies. The tool allows for a complete evaluation of the subglottical space when optical panendoscopy is incomplete due to intubation. It may be used for planning endoscopy-guided biopsies and surgery in the future. centrations were determined dynamically before and after exercise using a whole body MRI-system (Achieva, 3 T, Philips Healthcare). Point-RESolved spectroscopy (PRESS) was used to acquire spectra from a voxel in the M. vastus lateralis. The total creatine (t-Cr) peak was used as internal reference. Post-exercise acquisition of spectra started approximately 15 minutes after cycling. Results: Exercise-induced elevations of acetylcarnitine levels were similar in both groups (Δpost-pre 3.1±1.9 mmol/kg wet weight (ww)). However, post-exercise acetylcarnitine kinetics were significantly different (p < 0.05). In sedentary subjects, the concentration continued to increase during recovery towards a plateau at 40 minutes (8.5±0.3 mmol/kgww). In contrast, the acetylcarnitine concentration started to decrease from 5.8±0.5 mmol/kgww at 20 minutes after exercise in the trained subjects towards 4.4±1.0 mmol/kgww at 40 minutes. Conclusion: We demonstrate the dynamic character of acetylcarnitine in a situation of changing substrate demand/supply. The current protocol can differentiate between two metabolically different groups, which opens a window towards investigation of acetylcarnitine in relation to metabolic flexibility and insulin resistance. In vivo differentiation of muscle precursor cells using MR relaxometry N.C. Chuck, F. Azzabi Zouraq, D. Eberli, A. Boss; Zurich/CH (natalie.chuck@usz.ch) Purpose: To assess the differentiation process of muscle precursor cells (MPCs) applying magnetic-resonance-imaging (MRI) relaxometry and diffusion measurements in a mouse model in correlation with histology, immunohistochemistry and organ bath. Methods and Materials: Human MPCs were isolated from biopsies of the M.rectus abdominis. The MPCs were mixed with a collagen carrier and injected subcutaneously in nude mice. Animals with collagen-only-injections served as controls. MRI was conducted on a 4.7T small-animal-scanner (Bruker BioSpec) at 5 time points between day 3 and 21 post-injection. Relaxometry measurements comprised T1 and T2 measurements using multi-echo-spin-echo (TE 11-99 ms) and saturationrecovery-sequences (recovery time 118-4000 ms) and T2* quantification with a multi-echo-gradient-echo-sequence (TE1 = 4.5 ms, ΔTE = 7 ms, 12 echoes). Diffusion imaging was performed with a spin-echo-sequence including diffusion gradients with b=0.400 and 800s/mm 2 . Relaxation times and ADC values were measured in the skeletal muscles. Evaluations were performed with custom-made Matlab scripts. Animals were harvested after 28 days and the engineered muscle tissue was assessed by histology, organ-bath and immunofluorescence. Results: Relaxation and diffusion properties of the engineered tissue could reliably be measured at all time points. Relaxometry measurements revealed a decrease of T1, T2 and T2* relaxation-time during differentiation (initial measurement: T1 2242.6 ms±116, T2:224.3 ms±66, T2*:33.5 ms±4; final measurement: T1:1386.64 ms±88, T2:31.9 ms±4, T2*:10.8 ms±0.8), thereby approaching the physiological relaxation properties of muscular tissue. ADC showed a decrease from 2.24 mm 2 / s±0.26 to 1.51 mm 2 /s±0.05. Cell differentiation and myofibre formation was confirmed by histology, immunohistochemistry and contractility confirmed by organ bath. Conclusion: We demonstrated that MRI relaxometry measurements are able to describe the differentiation of muscle precursor cells. This method might offer the possibility to non-invasively assess the effectiveness of cellular therapies for muscular disorders in near future. Purpose: To evaluate diagnostic accuracy of diffusion-weighted magnetic resonance imaging (DWI) in predicting response to neo-adjuvant chemo-radiotherapy (nCRT) in patients with locally advanced cervical carcinoma using apparent diffusion coefficient (ADC). Cervical lesions ADC were correlated with post-surgical histopathology. Methods and Materials: 24 women (FIGO>IB Bulky) underwent MRI and DWI prior to, after 2 weeks and at the end of nCRT, using 1.5 T scanner. Cervical lesion volume and ADC were measured at each assessment. Radical hysterectomy was performed 4 weeks after MRI. Treatment response was determined based on histopathology and was classified as complete response (CR), residual (RD) or stable disease (SD). Mean ADCs (mADC), ADC increase and volume reduction (VR) rates were compared using histopathology as reference standard Results: According to histology, 13/24 (54%) had CR, 11/24 (46%) had RD < 1 cm. 2 patients presented SD. Before therapy, in the study population mADC was 0.96±0.06x10-³ mm²/s but it was lower in SD (0.76±0.1x10-³ mm²/s). After 2 weeks of nCRT, mADC correlated with tumour response: a) in CR with 23% percent change (1.20±0.02x10-³ mm²/s vs 0.98±0.06x10-³ mm²/s; P < 0.001); b) in RD with 10% percent change (1.05±0.02x10-³ mm²/s vs 0.93±0.06x10-³ mm²/s; P < 0.001). Tumour volume decreased in CR and RD with reduction rate of 48% and 46%, respectively. At the end of CRT, no significant differences on ADC between For comparison of quality data, Chi-square and odds ratio were used. Results: In 80 subjects (67%), 114 benign (63.5%) and 6 malign (3.5%) lesions were detected. Six subjects underwent operation (5%) for adrenal carcinoma, renal carcinoma, pancreatic mucinous cystadenoma, intradural schwannoma (2), and enchondroma of the femur. In one subject, tuberculosis pneumonia was detected and medical treatment was given. In 3 subjects focal nodular hyperplasia of the liver, and in one an unclassified solid mass in spleen were encountered and they are in follow-up. The most common incidental lesions were liver cyst (12), liver haemangioma (9), renal cyst (13), and thyroid nodule (6). No significant difference was observed for the incidence of benign and malign lesions between subjects aged ³40 years and < 40 years (p=0.209 and p=0.898, respectively). Conclusion: 7% of the population screened by WB-MRI underwent further surgical and medical treatment. WB-MRI is a useful and non-invasive tool for the detection of incidental lesions in asymptomatic subjects. Purpose: To assess the value of elasticity parameters on breast sonoelastography by influence of menopause factor. Methods and Materials: 286 female patients (premenopausal vs postmenopausal: 192 vs 108) with 300 breast lesions were conducted routine ultrasound and elastographic ultrasound preoperatively. The elastic parameters of strain ratio (SR, SR1 was calculated using the same-level and normal-appearing breast region as reference; SR2 was calculated using the subcutaneous fat as reference) were then obtained, with the pathologic diagnosis served as golden standard. The sensitivity, specificity, and area under the curve were analysed by receiver operating characteristic (ROC) curve with or without the influence of menopause factor. Purpose: To assess if stiffness as measured by shear-wave elastography (SWE), could be an early biomarker of response to chemotherapy in a breast cancer model. A human invasive ductal carcinoma was implanted subcutaneously in 10 athymic female mice. After 8 weeks of growth, 2 tumours were removed for baseline pathological analysis and 8 were treated by oral chemotherapy during 5 weeks. Ultrasound was performed every week before and during treatment, using a superficial 8-MHz probe. Maximum diameter and mean elasticity value of the tumor were measured. Kinetics of changes in diameter and elasticity before and under treatment were calculated as the slope of diameter or elasticity over time. At the end of the treatment, tumours were removed for pathological analysis. Results: Before treatment, we observed a progressive stiffness increase along tumour growth (slope: 8.8 kPa/week). Under chemotherapy, we observed an early stabilisation of tumour stiffness (slope: -0.8 kPa per week). Furthermore, a significant decrease of elasticity values was seen after four weeks of treatment (p=0.03). We also observed an early progressive decrease of diameter showing that there was a good response to treatment. After five weeks of treatment, we observed modifications of the pathological features of the tumor, i.e. mainly a decrease of cellular density. Conclusion: In our model, we observed an early stabilisation of tumour elasticity with an inversion of elasticity slope under treatment showing that SWE could be an interesting tool to assess early tumor response to chemotherapy. Purpose: Shear wave elastography (SWE) can differentiate benign from malignant solid breast masses. Small, low-grade cancers can have benign (low) mean stiffness values but often show a ring of slightly stiffer tissue around the lesion. We aimed to establish whether taking the presence of a ring sign to indicate malignancy improves the discriminatory performance of SWE in screen detected solid breast masses. The ring sign was defined as the presence of stiffer borders on at least 2 aspects of the lesion. The presence or the absence of the ring sign was independently assessed by two breast radiologists, blinded to pathology outcomes, in a consecutive series of 145 screen-detected solid masses. A third radiologist arbitrated in discordant cases. The discriminatory performance of SWE using a threshold mean stiffness value of 50 kilopascals (kPa) was compared with taking either a threshold mean stiffness of 50 kPa or a ring sign as positive. Results: Of 145 masses, 42 were benign and 103 were malignant. In 122 (84%), the ring sign findings of two radiologists were concordant. For mean stiffness threshold of 50 kPa, sensitivity was 83% and specificity was 55%. When either mean stiffness over 50 kPa or a ring sign was counted as positive, sensitivity was 91% and specificity was 45%. The increase in sensitivity was statistically significant (Fisher's exact test, p=0.048). The drop in specificity was not (p=0.25). The ring sign can improve the sensitivity of shear wave elastography in differentiating benign from malignant screen-detected solid breast masses. Purpose: The purpose of our study was to investigate arterial spin labelling (ASL) MRI for functional assessment of transplanted kidneys at 1.5 T and 3 T. Methods and Materials: 105 renal allograft recipients (mean age 50.8 ± 14.7 years) were included in this study. ASL MRI was performed at 1.5 T (n=71) and 3 T (n=34) using a single-slice paracoronal FAIR TrueFisp sequence (30 averages, inversion time 1200 ms, slice thickness 8 mm, matrix 128 x 128). For quantification of ASL perfusion, T1 relaxation times were determined at 1.5 T and 3 T using the variable flip angle approach. ROIs were drawn by a single reviewer on ASL parameter maps for quantification of cortical perfusion. ASL perfusion was correlated with allograft function as determined by the estimated glomerular filtration rate (eGFR) and compared between patients with good or moderate allograft function (group a; eGFR > 30 ml/min/1.73 m²) and patients with heavily impaired allograft function (group b; eGFR ² 30 ml/min/1.73 m²). Results: ASL perfusion and eGFR were comparable at 1.5 T (36.1 ± 22.6 ml/ min/1.73 m² and 237 ± 101 ml/100 g/min) and 3 T (42.3 ± 22.2 ml/min/1.73 m² and 248 ± 66 ml/100 g/min). ASL perfusion was significantly higher in group a (283.9 ± 59.4 ml/100 g/min) as compared to group b (195.6 ± 62.0 ml/100 g/min) (p < 0.0001). ASL perfusion values exhibited a significant correlation with eGFR (r=0.59, p < 0.0001). A total of 151 patients were enrolled at 5 centers in Japan. All patients provided written informed consent before entering the studies. Unenhanced ultrasound, contrast-enhanced ultrasound, and contrast-enhanced MR images were independently assessed by three blinded reviewers, who viewed the different images in a randomised sequence and were also blinded to subject characteristics. The observation period for safety assessment was 3 days after the contrast agent administration. Results: Among 140 patients included in the diagnostic analysis, the accuracy of contrast-enhanced ultrasound (86.7%) was significantly higher than that of unenhanced ultrasound (66.9%) and contrast-enhanced MRI (69.5%) (both p < 0.001). Sensitivity and specificity of contrast-enhanced ultrasound (92.9%, 84.0%) were also superior to unenhanced ultrasound (86.5%, 58.5%) and contrast-enhanced MRI (86.5%, 62.2%) (sensitivity: p=0.177 and p=0.160) (specificity: both p < 0.001). The incidence of adverse events was 9.9%, with adverse drug reactions in 3.3% (all mild). Conclusion: Compared with unenhanced ultrasound and contrast-enhanced MRI, contrast-enhanced ultrasound with SONAZOID ® (Perflubutane) microbubbles achieved significantly better diagnostic accuracy and specificity for breast lesions without causing serious adverse reactions. Methods and Materials: In a retrospective study, 21 patients with non-tumorous increased signal intensity of the kidneys on DWI sequences (b=800s/mm2) and corresponding ADC-decrease was identified. As a control group served 60 patients without clinical signs of renal infection. All patients underwent routine MRI-protocol of the abdomen including EPI-sequence for the DWI (b.0/400/800), T2w HASTE, T1w VIBE post-contrast (Dotarem). Confirmation of renal infection was established on the basis of clinical criteria. T1w-and T2w-images were assessed and compared to DWI for the presence of altered signal and the degree of the visibility of pathology was graded on an three-point scale. In all 21 patients with positive DWI-findings, a renal infection could be confirmed while none of the patients in the control group showed a suspicious signal pattern on DWI. T2w-imaging and contrast-enhanced T1w-imaging displayed obvious pathologic signal in 3/21 (14%) and 11/19 (58%) patients, slightly pathologic signal in 17/21 (81%) and 7/19 (37%), respectively. No pathologic change was seen in 1/21 (4%) and 1/19 (5%). The median visibility score of 2 for the DWI-imaging and the T1w-images was significantly higher than the median visibility score of 1 for the T2w-imaging (p=0.0001 (DWI vs. T2w) and p=0.078 (T1w vs. T2w). No significant differences were found between the visibility scores of T1w imaging and DWI. Conclusion: DWI of the kidneys seems to be highly sensitive for the detection of infections within the kidney. Purpose: To investigate feasibility dynamic-contrast-enhanced (DCE)-MRI assessment of kidney function and renal masses on a single slice compared with investigation of the whole organ or tumour. Methods and Materials: Fourteen patients with renal tumours (11 renal cell carcinomas, 2 angiomyolipoma, 1 oncocytoma) before and after partial nephrectomy underwent DCE-MRI at 3 T (Magnetom VERIO, Siemens Healthcare Sector) with a time-resolved angiography with stochastic trajectories (TWIST)-sequence (voxelsize 2.6x2.6x2.6 mm 3 , temporal resolution 2.5 mm) with half-dose Gadobutrol (Bayer Healthcare Pharmaceuticals). 28 kidney datasets and 14 tumour datasets were assessed using in-house built IDL-software PMI 0.4. Using 2-compartment-models with semi-automated segmentation, renal perfusion and filtration as well as tumour perfusion and permeability were calculated for a single central Region-of-interest on a single slice or the whole organ or tumour. Statistical analysis was performed with paired t-tests and Pearson´s correlation coefficient. Results: There were no significant differences between single slice / whole kidney (plasma-flow 275.8±105.6 vs. 234±96.7 ml/100 ml/min, plasma-volume 28.2±8.9 vs. 25.0±9.0 ml/100 ml, glomerular-filtration-rate 16.9±9.2 vs. 15.9±8.0 ml/100 ml/ min) as well as between single slice/ whole tumour (plasma-flow 122.5±85.6 vs. 120.5±95.2 ml/100 ml/min, plasma-volume 18.9 vs. 13.0 ml/100 ml and permeabilitysurface-product 5.4±7.9 vs. 5.4±8.3 ml/100 ml/min). Correlations between single slice and whole organ/ tumour was were excellent and significant for all parameters (r = 0.95 to 0.99, p < 0.01). Conclusion: Single slice assessment of kidney function and renal masses with DCE-MRI does not show significant differences to the more time-consuming analysis of the whole organ/ tumour. Incorporation of single slice analysis of DCE-MRI data in future studies appears feasible and justifiable. In vivo sodium ( Purpose: Renal allograft rejection is associated with chemokine ligand 2 (CCL2)dependent glomerular and interstitial macrophage recruitment. CCL2 blockade with the Oligonucleotide/Spiegelmer mNOX-E36-3'PEG inhibits leucocyte recruitment. The purpose of this study was to evaluate MR renography and diffusion-weighted imaging (DWI) for assessment of this novel chemokine-directed therapy in an experimental murine animal model. Methods and Materials: An orthotopic renal transplant mouse-model with acute allograft rejection (balb/c into C57/BL6) was used. 5 animals were treated with low-dose cyclosporin A in combination with mNOX. 7 animals did not receive treatment. 3 syngenic controls (C57/BL6 into C57/BL6) were performed. Imaging was conducted at 3 T with a dedicated mouse coil. Diffusion-weighted imaging was performed with b values ranging 0 to 800 s/mm2. MR renography was performed with a TWIST-sequence with a temporal resolution of 1.5 seconds following a bolus of 10µl gadobutrol in 100µl NaCl. Significance between subgroups was assessed with Wilcoxon´s rank-sum test. Results: Syngenic allograft showed substantially higher plasma flow (53.2±17.2 ml/100 ml/min) and significantly lower (p < 0.05) ADC (1.20±0.02 mm2/s) than native kidneys (44.1±7.1 ml/100 ml/min and 1.29±0.09 mm2/s). Allograft-ADC of treated animals (0.98±0.14 mm2/s) was substantially higher than of untreated animals (0.76±0.17 mm2/s). Cortical plasma flow (24.5±5.5 ml/100 ml/min) was significantly lower (p < 0.05) for untreated animals compared to treated animals (37.4±7.6 ml/100 ml/min). Volume of distribution and mean transit time did not show significant differences between the subgroups. Conclusion: Chemokine-directed treatment ameliorates acute renal allograft rejection. Functional MRI is able to non-invasively assess these therapy effects in this experimental model and holds high potential to become an alternative to invasive organ biopsy. Assesment cisplatin-induced interstitial nephropathy using diffusion-weighted MRI R. Del Vescovo, F. Giurazza, R.L. Cazzato, C.L. Piccolo, R.F. Grasso, B. Beomonte Zobel; Rome/IT (r.delvescovo@unicampus.it) Purpose: To assess the potential of noninvasive diffusion-weighted magnetic resonance imaging (DW-MRI) to depict interstitial kidney changes in patients (pts) under cisplatin-based chemotherapy. We analysed ADC maps of 34 oncologic patient (5 woman and 29 men; mean age 56 years; 50% affected by advanced lung cancer) treated with cisplatin-based chemotherapy comparing with age-and sex-matched control group's ADC maps. The creatinine clearance (CrCl) used to determinate renal function was based on the formula of Crockfort (normal value > 60 mL/min). The ADC values were calculated using a ROI positionated manually on the cortex of each pole in axial and coronal images. For statistical analysis t-test was used. A p value of less than 0.05 was considered significant. Results: There was no anatomical difference visible with conventional MR imaging of the cortex and medulla relationship. In pts treated with cisplatin there was a reduction of ADC values in the cortex, but no significant changes in medulla. The ADC values of healthy volunteer were significantly higher comparing with patients treated with cisplatin (p < 0.04). There was no significant difference between the ADC values of left and right kidney in each patient except in one who present a unilateral ureteral obstruction. No significant correlation was found between the creatinine clearance and ADC values obtained in both groups. Conclusion: DW-MRI may allow a noninvasive detection of changes in kidneys in pts with interstitial nephropathy during and after chemotherapy treatment. Purpose: To investigate the feasibility of reconstructing anatomic connectivity of sacral plexus using 3 T-MR diffusion tensor imaging (MR-DTI) with three-dimensional (3D) tractography approach. 3 T-MR-DTI was performed on 10 women volunteers. The sequence was acquired on oblique axial plane parallel to the sacrum, from the level of the L4 nerve to the coccyges. Main diffusion directions reflecting the fibre orientation were determined using a Sense-SSEPI with diffusion-sensitised gradients (b600 mm2s-1) along 16 directions. A deterministic bre-tracking algorithm was used to show fibre architecture, compared with anatomic atlas. Three ROIs were placed at different levels of the spinal cord nerves: one in the middle of each tract-of-interest, accompanied by "AND" selection ROIs at both ends of the nerve tract ROI. Diffusion-weighted Ssh-EPI images are processed on a dedicated workstation for data pre-processing with MedINRIA deterministic software. Results: Tractography of the sacral plexus was feasible for all 10 volunteers, giving 3D insight into the general anatomy and organisation of the nerves L4 to S4. Main artefacts in fibre reconstruction, caused by bladder over-distension, by presence of air in rectum and by constant small movements due to breathing and/or spontaneous contractions of pelvic organs, never invalidate the feasibility of tractography. Fibres were reconstructed from medulla to the pelvic course of main branches of sacral-plexus nerves. Emerging branches of pudendal nerve were found in 6 volunteers. Conclusion: 3 T-MR-DTI allows a precise anatomic reconstruction of lumbar-sacral plexus. These findings are encouraging for using DTI as a mean to investigate sacral-plexus, especially in female pelvis. TE=2.64 ms to 60.42 ms; TR=75 ms; 24 averages; measurement time=46:50 min). All HR images were corrected for inhomogeneous sensitivity of coil. The 23 Na-SNR values are given on a pixel-by-pixel basis for 20 mm from the renal cortex in the direction of the medullary pyramid. The T2* maps were calculated by fitting the 23 Na signal decay mono-exponentially on a pixel-by-pixel basis using least squares fitting routine written in IDL. Results: The mean cortico-medullary 23 Na-SNR for all 16 healthy kidneys increased from the renal cortex (34.1 ± 10.2) towards the renal medullary pyramid (88.8 ± 20.9). The cortico-medullary increase ranged inter-individually from 50.8 to 65.7%. The mean 23 Na-T2* of all volunteers was 19.9 ± 1.8 ms. The feasibility of ultra-high field, HR 23 Na-MRI of healthy human kidneys was demonstrated. Moreover, high 23 Na-SNR provided by 7.0T allowed the in vivo measurements of 23 Na-T2* times in human kidneys for the first time. Arterial spin labelling for the prostate: initial experience at 3 T MRI S. Takahashi 1 , N. Aoyama 1 , T. Kimura 2 , K. Kitajima 1 , Y. Ueno 1 , S. Sato 3 , K. Sugimura 1 ; 1 Kobe/JP, 2 Otawara/JP, 3 Osaka/JP (staka@med.kobe-u.ac.jp) Purpose: To assess the value of ASL-perfusion MRI for the prostate using dynamic contrast-enhanced (DCE) study findings as the reference standard. Methods and Materials: 22 male patients (mean age 69.2 ± 7.6 years) with suspected prostate cancer were prospectively included in this study. Single-slice 2D-pulsed ASL images were acquired during our routine prostate screening protocol on a 3 T MRI unit, including the DCE study. First, ROI was drawn for the obturator muscle on a control image of ASL sequence (Scont.ref). Then, ROIs were drawn for the femoral artery, the obturator muscle, the normal PZ and the regions where DCE showed early enhancement on the tagged ASL image. These values were divided with Scont.ref, yielding an ASL ratio (ASLR). Analysis of the variance was performed to assess differences in ASLR for each tissue or region. A radiologist scored the degree of enhancement on DCE and compare to the contrast ratio of ASLR and the visual assessment of ASL signals. Results: A mean ASLR of the femoral artery was 15.8±6.9%, where those of the normal PZ and the obturator muscle were 0.6±0.5%, and 0.6±0.5%, respectively. On the other hand, the enhanced regions on DCE showed a mean ASLR of 0.98±1.0%. Visual assessment of the ASL image detected 7 out of 12 well-enhanced regions. Contrast ratio of ASLR demonstrated significant positive correlation to the degree of enhancement on DCE (Spearman; r=0.54, p=.007). Conclusion: ASL may allow detecting the region of the higher tissue blood flow in the prostate without contrast materials. Purpose: Aim of this study was to investigate the feasibility of contrast-enhanced 7 Tesla MRI of the female pelvis. Methods and Materials: 10 healthy female volunteers were examined on a 7T whole body MR system (Magnetom 7T, Siemens) utilising an 8-channel transmit/ receive radiofrequency body coil. The examination protocol included 1) T1w fs 2D FLASH, 2) dynamic T1w fs 3D FLASH, 3) T2w TSE sequences. For qualitative image analysis of T1w MRI, the delineation of pelvic anatomy, pelvis vasculature, tissue contrast and overall image quality was assessed and for T2w MRI the zonal anatomy of the uterus and the conspicuity of the ovaries were evaluated (fivepoint-scale analysis: 5 = excellent to 1 = non-diagnostic). Image impairment due to various artefacts was assessed. Contrast ratios between junctional zone and myometrium were obtained via ROI analysis for T2w MRI. Results: Of all three sequences, 2D FLASH MRI offered best overall image quality (mean contrast-enhanced 4.75) and highest tissue contrast (mean contrastenhanced 4.92). For the T1w sequences, 2D FLASH imaging was rated with higher scores for all assessed structures than 3D FLASH MRI. T2w TSE imaging provided a moderate to high conspicuity of the zonal anatomy of the uterus with mean scores ranging from 3.5 for endometrium to 4.67 for myometrium. Overall image impairment was rated strongest for T2w MRI (2.95) and least for 2D FLASH MRI (mean 4.24). Our results indicate the successful transformation of the associated high SNR into high spatiotemporal resolution T1w pelvis MRI at 7 T and valuable non-contrast diagnostics of pelvis vasculature. DE (david.schneider@stud.uni-heidelberg.de) Purpose: High vessel attenuation as well as a high contrast-to-noise (CNR) ratio is a prerequisite for highly diagnostic cervical and cerebral CT-angiographic examinations. The purpose of this study was to evaluate the value of calculated low-kV-monoenergetic dual-energy CT (DECT) angiographic datasets. Methods and Materials: 41 patients (21 men, mean age 58 ±14) that underwent DECT-angiography of the cervical (n=7) or cerebral vessels (n=34) were retrospectively included in this study. 80 and 140-kV DECT data were used to calculate low-kV monoenergetic image datasets from 120 to 40 keV (10-keV intervals). Vessel and soft tissue attenuation and image noise were measured in various regions of interest and the CNR was subsequently calculated. Differences in image attenuation and CNR were compared between the different monoenergetic datasets. Vessel attenuation and CNR of the best monoenergetic datasets were then compared to conventional 120-kV polyenergetic datasets. Results: In comparison to conventional polyenergetic 120-kV datasets, above all, 60-keV monoenergetic cervical datasets yielded to a significant increase in vessel attenuation and CNR (+40%, +18%; all p < 0.01). For cerebral vessel assessment, in particular 70-keV monoenergetic datasets improved vessel attenuation and CNR (+3%, +10%; all p < 0.01) when compared to conventional 120-kV datasets. Conclusion: Calculated 60-keV monoenergetic image data significantly improves vessel attenuation as well as the CNR of cervical DECT-angiographic studies, whereas 70-kV monoenergetic datasets are favourable to improve vessel attenuation and the CNR of cerebral DECT-angiographic studies. Thus, lowering the amount of iodinated contrast-material might become feasible using monoenergetic-low-kV images, which is particularly important for combined perfusion and angiography protocols. Purpose: Single case reports suggest that black blood MRI (T1-weighted fat and blood suppressed sequences with and without contrast injection; BB-MRI) may visualise intracranial vessel wall contrast enhancement in primary angiitis of the central nervous system (PACNS). In this single-centre observational pilot study we prospectively investigated the value of BB-MRI in the diagnosis of large artery PACNS. Methods and Materials: In this prospective, mono-centric study 12 patients with suspected large artery PACNS received a standardised diagnostic programme including BB-MRI. 10 patients without any evidence of PACNS and without intracranial stenosis served as control group. Vessel wall contrast enhancement was graded (grade 0-2) by two experienced readers blinded to clinical data and correlated to the final diagnosis. Results: Four of 12 included patients received a final diagnosis of PACNS. All of them showed moderate (grade 1) to strong (grade 2) vessel wall contrast enhancement at the sites of stenosis. A moderate (grade 1) vessel wall CE grade was also observed in 6 of the remaining 8 patients in whom alternative diagnoses were made: arteriosclerotic disease (n=4), intracranial dissection (n=1), and Moyamoya disease (n=1). None of the patients in the control group had vessel wall contrast enhancement. Conclusion: Our pilot study demonstrates that vessel wall contrast enhancement is a frequent finding in PACNS and its mimics, but it is absent in patients without evidence of intracranial vascular disease. Larger trials will be necessary to evaluate the utility of BB-MRI in the diagnostic workup of PACNS. Purpose: The availability of endovascular services is increasing, but still not available in the majority of TPA centres. The aim of this study was to describe the relations between NIHSS and large vessel occlusions in patients with hyper-acute ischaemic stroke. A prospective single hospital registry based on consecutive patients admitted for TPA work up with routine CTA was started on July 1, 2009; this analysis is based on patients admitted before December 2011. Bispebjerg University Hospital has a TPA-service with a catchment area of app. 1.7 mio. inhabitants on even dates. CT scans are performed using 64-section MDCT (Brilliance-64, Philips Healthcare) with CTA from the aortic arch to the vertex. All images were systematically reviewed by a blinded neuroradiologist; sensitivity, specificity, positive predictive value and negative predictive value were calculated at all levels of NIHSS. Results: Five-hundred and seventy-three patients with acute ischaemic stroke were entered into the registry. At a NIHSS score equal to or larger than 10, the sensitivity was equal to 43.8%, the specificity was 89.6% the positive predictive value was 63.2% and the negative predictive value was 89.6% in predicting an acute occlusion. Conclusion: If the cut off is set at NIHSS 10, there is a 10% risk of missing an occlusion and a 37% risk of transporting a patient with a TPA drip for no reason. The relation is between occurrence of large vessel occlusions and NIHSS is a continuum. Contribution of the temporal maximum intensity projection ( Purpose: The goal of retrospective study was to compare possibilities to measure the extent of MCA occlusion (thrombus length) in patients with acute stroke and predictive value for recanalization and clinical outcome after systemic therapy. We analysed 63 patients with MCA occlusions (25 males, average age 72.3 years, range 23-91 years) detected with multimodal CT examination (non-contrast CT, perfusion CT and conventional CTA). Conventional CTA (slice 0.6 mm) and temporal maximum intensity projection (tMIP) datasets (slice 1.5 mm) reconstructed over the full time span from volume CT perfusion were used for thrombus length measurement. Results of used techniques were compared and correlated with results of systemic thrombolytic therapy (24 hours recanalization and 3-month clinical outcome). Results: There was no statistically significant difference in measurement results using conventional CTA and tMIP, but in 23 subjects (36%) measurement of thrombus was not possible using conventional CTA due to unclear peripheral border of thrombus. We proved statistically significant correlation of whole extent of thrombus and recanalization success (p=0.0241). The involvement of M2 section was main negative factor for recanalization (p=0.0068). The strong significant correlation of thrombus length and 3-month clinical outcome was proved (p=0.0079) with cut-off value of 11 mm. Conclusion: Our results confirm the benefits of detailed evaluation of cerebral arteries using tMIP datasets, which enable to measure thrombus length in all subjects in comparison to conventional CTA. The thrombus length was established as negative factor for recanalization and clinical outcome after systemic thrombolytic therapy. that with an optimised MR-protocol, mural inflammatory changes of superficial extracranial and intradural arteries can be detected in patients with GCA. Methods and Materials: 10 patients with suspected GCA underwent 3.0 Tesla MRI, including fat saturated (fs) T1w scans pre-and post-contrast, optimised for assessment of intradural VWE, and high-resolution fsT1w scans to evaluate superficial extracranial vessels. Temporal artery biopsies were available in 4 cases. VWE of intradural and extracranial vessels was evaluated by two observers Results: In 5 patients, GCA was diagnosed clinically, in 4 biopsy proven. A clear VWE of superficial extracranial vessels was detected in 8 cases. Clear VWE of the intradural internal carotid artery (ICA) was detected in 6 cases, 5 with corresponding vessel wall thickening. Slight enhancement of the right medial cerebral artery was seen in 1 case. In one patient with GCA, no VWE of intradural or extracranial vessels was detected. One patient who did not receive a temporal artery biopsy presented with VWE of intradural and extracranial arteries, but the final clinical diagnosis was connective tissue disease. Conclusion: VWE of extracranial vessels is a frequent finding in GCA. Additionally, VWE of intradural arteries, mainly the ICA, can be found. Therefore, high-resolution MRI seems to be a feasible technique to visualise vasculitic involvement of the extra-and intracranial arteries in GCA. Purpose: To measure cerebrovascular reserve using fMRI (CVR fMRI) in patients with severe stenosis of the middle cerebral artery (MCA) to identify those at risk of haemodynamical stroke. Methods and Materials: Among 16 patients with severe intracranial arterial stenosis, 7 patients (4 females; 61.9±18.5years) had a stenosis of the right (n=4) or left (n=3) MCA only. CVR fMRI was performed using BOLD contrast with a block-design hypercapnic challenge (CO2 7%) at 3 T. Averaged end-tidal CO2 pressure (EtCO2) was used as regressor for statistical analyses. We measured %BOLD/mmHg EtCO2 on segmented grey matter of MCA territories. We calculated a laterality index with LIMCA =(Left_CVR-Right_ CVR)/(Left_ CVR+Right_ CVR). LI were compared to those obtained in 100 volunteers that provided a 99% confidence interval for | LIMCA |< 0.08. Basal perfusion was measured using dynamic susceptibility contrast. Results: Basal perfusion measurements were symmetrical in all patients. No adverse reaction to hypercapnia was detected. CVR values ranged from 0.13 to 0.37 with m±sd=0.25±0.07. Among these 7 patients, three patients had a normal |LIMCA|< 0.08 ranging from 0.02 to 0.05 (0.04±0.01), and four patients had an abnormal |LIMCA|> 0.08 ranging from 0.13 to 0.17 (0.16±0.02). All abnormal LI values identified the MCA territory ipsilateral to the stenosis. Conclusion: These preliminary results show that among patients with severe stenosis of MCA, several patients have abnormal |LIMCA| in the territory ipsilateral to the stenotic artery, suggesting significant CVR impairment that might be at risk of haemodynamic stroke. CVR fMRI should be considered to better define treatment strategy, including intravascular stenting. Purpose: In this study, we aimed to evaluate the endothelial functions in patients with nonalcoholic fatty liver disease (NAFLD). In this observational case-control study, a total of 51 patients with NAFLD and age and sex-matched 21 healthy controls were enrolled. In both patients and controls, levels of asymmetric dimethylarginine (ADMA), systemic endothelial function (brachial artery flow-mediated dilation) (FMD) and carotid artery intima-media thickness (C-IMT, mm) were measured. Endothelial functions of the brachial and carotid arteries were evaluated by vascular ultrasound. Results: Carotid intima media thickness was significantly higher in patients with NAFLD than controls (0.67±0.09 versus 0.52±0.11 mm, P < 0.001). The average C-IMT measurements were found in groups of control, simple steatosis and NAFLD with (borderline and definitive) NASH as 0.52±0.11, 0.63±0.07 and 0.68±0.1 mm, respectively. The differences between groups were significant (P < 0.001). Measurement of brachial artery FMD was significantly lower in patients with NAFLD compared to controls (7.3±4.8 versus 16.5±7.1%, P < 0.001). FMD measurements in groups of control, the simple steatosis and NAFLD with NASH as 16.5±7.1, 9.64±6.63 and 7.03±4.57%, respectively, and the differences were statistically significant (P < 0.001). The increase in C-IMT and decrease in FMD were independent of metabolic syndrome and it was also more evident in patients with simple steatosis and NASH compared to controls. Conclusion: Our data suggested that NAFLD is associated with endothelial dysfunction and increased early atherosclerosis compared to healthy subjects. Purpose: This study aimed to assess image quality and radiation dose of CT angiography (CTA) in kidney donors obtained with automated kVp selection and sinogram-affirmed iterative reconstruction (SAFIRE), using scans with fixed kVp and filtered back projection reconstruction algorithm as the comparison. Methods and Materials: Mean attenuation, contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) at abdominal aorta, right renal artery (RRA) and left renal artery (LRA) were measured in 24 kidney donors who had undergone CTA with tube current modulation, 120 kVp, filtered back projection reconstruction algorithm (Group A) and were compared with 24 BMI-matched kidney donors who had undergone CTA with automated kVp selection and SAFIRE (Group B Purpose: Cerebral small vessel disease (SVD) is a common cause of cognitive impairment. White matter hyperintensities (WMH) and lacunar infarcts are the commonest magnetic resonance imaging (MRI) parameters observed in clinical practice. The relationship between these findings on MRI and cognitive impairment remains unclear. The aim of our study was to determine the relationship between lacune count, total lacune volume and location of lacunes with cognition. Methods and Materials: Patients with lacunar stroke and WMHs were recruited to the prospective SCANS study. Baseline data (n=121) was used for this analysis. Multimodal MRI and neuropsychological testing were performed. Lacunes were identified and counted by a neuroradiologist on a T1 image, then mapped using an automated region growing technique. Lacunar volume was calculated from the resulting masks, and lacunar location automatically determined by projection onto standard atlases. T2 WMH volume and brain volume were also measured. Results: In multiple regression controlling for WMH volume and brain volume, both the lacune number and the total volume were related to a significant decrease in executive function (number: Beta=-0.21, p < 0.006; volume: Beta=-0.16, p < 0.04) and processing speed (number: Beta=-0.26, p < 0.001; volume: Beta=-0.24, p < 0.004). Lacunes in the thalamus were associated with impaired processing speed performance (p < 0.002). One can infer a number of things relating to cognitive impairment when looking at an MRI scan of a patient with cerebral small vessel disease. 1) The number of lacunes are a better predictor of cognitive status than diffuse WMH and 2) thalamic lacunes, in particular, are associated with impaired processing speed. Purpose: To perform qualitative and quantitative analysis of altered haemodynamics of liver cirrhosis patients after TIPS-stent-graft implantation and volunteers using time-resolved flow-sensitive 4D MRI at 3 T. Our study group consisted of 5 liver cirrhosis patients including an examination before and after stent-graft implantation as well as 10 volunteers. 3D liver flow characteristics in the arteries and portal vein were evaluated using flow-sensitive 4D MRI at 3 T MRI with a spatial resolution of 1.6x2.1x2.4 mm³ and temporal resolution of 62.4 ms. Hepatic flow visualisation was performed using 3D streamlines and time-resolved particle traces. Quantitative evaluation included retrospective extraction of regional maximum and mean velocities, flow volume, vessel area as well as pulsatility and resistance indices. Results: 3D streamlines and particle traces visualisation in the arterial and portal venous system could successfully be performed for almost all patients and volunteers. Quantitative results reveal maximum and mean velocities tend to be lower in MRI compared to Doppler Ultrasound, area showed significant lower values for US (p < 0.01). Comparing the changes after TIPS-stent-graft implantation the data results demonstrated an increase of velocities and flow volume in the venous system as well as hepatic artery. Conclusion: Flow-sensitive 4D MRI enabled a qualitative and quantitative evaluation of arterial and portal venous haemodynamics of liver cirrhosis patients before and after TIPS-stent-graft implantation including a volunteer group. Flow-sensitive 4D MRI may be a standardised method with complete volumetric and functional coverage of the blood flow haemodynamics providing additional information in patients after TIPS-stent-graft implantation. on a 5-point-scale. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) was calculated with ROI measurements. Results: SNR of the common carotid artery and middle cerebral artery was 53.6±22.7 and 43.3±15.3 (group A) versus 54.1±20.5 and 46.2±14.6 (group B). CNR was 40.0±19.3 and 29.7±12.0 (group A) compared to 40.7±16.8 and 32.9±10.9 (group B). Subjective IQ was excellent in both groups (mean score 4.4±0.7 versus 4.4±0.6). Differences between the two groups were not significant. The OSDR algorithm XCare™ does not compromise IQ of head and neck CTA. Its application can be recommended for CTA in clinical routine to protect the thyroid gland and ocular lenses from unnecessary high radiation. Precision of pulmonary vein diameter measurements assessed by CE-MRA and steady-state-free precession imaging F. Henes, P. Bannas, M. Regier, J. Buhk, K. Müllerleile, G. Adam, M. Groth; Purpose: To evaluate inter-and intraobserver reliability of pulmonary vein (PV) diameter measurements by contrast-enhanced magnetic resonance angiography (CE-MRA) and ECG-gated 2D unenhanced steady-state-free precession sequences (SSFP). Methods and Materials: CE-MRA and SSFP of 60 PV in 17 patients were evaluated. PV diameters were measured in transverse and coronal orientation at predefined levels by two independent readers. Intraclass correlation coefficient (ICC) and Bland-Altman analysis (BA) were used to assess inter-and intraobserver reliability and variances. F-test was performed for comparison of intra-and interobserver variances. Pearson´s correlation coefficient and BA were used to compare CE-MRA and SSFP. A t-test was used to determine possible significant differences between the measurements. Results: There was moderate correlation (R = 0.68, transverse; R = 0.66, coronal) without significant difference in diameter measurements between CE-MRA and SSFP (p = 0.15, transverse; p = 0.25, coronal). Intraobserver limits of agreement (LAG) ranged between ±0.50 cm (transverse) and ±0.86 cm (coronal) for CE-MRA versus ±0.40 cm (transverse) and ±0.67 cm (coronal) for SSFP. Interobserver agreement showed LAG ranging between ±0.59 cm (transverse) and ±0.83 cm (coronal) for CE-MRA versus ±0.34 cm (transverse) and ± 0.75 cm (coronal) for SSFP. Only transverse SSFP measurements revealed ICC > 0.75. Intra-and interobserver variances did not reveal significant differences between CE-MRA and SSFP in any orientation (all p-values > 0.05). Conclusion: SSFP and CE-MRA enable comparable precision of PV diameter measurements. However both methods revealed a wide range of intra-and interobserver agreement, which has to be thoroughly considered in the clinical use. The application of CT angiography with whole brain perfusion imaging in the evaluation of patients with transient ischaemic attack H. Shi, F. Yang, X. Ma, W. Guo, S. Dong, M. Qiao; Beijing/CN (shihuiping@yahoo.com) Purpose: To investigate the 320-row low-dose volume CT perfusion imaging combined with CT angiography in the evaluation of cerebral microcirculation changes of transient ischaemic attack (TIA). Sixteen cases of TIA patients (male 11, female 5) underwent 320 row of dynamic volume CT perfusion imaging combined with CT angiography during 40 ml 370 mgI/ml contrast agent injection and acquired the blood flow perfusion parameters such as regional cerebral flow (rCBF), regional cerebral volume (rCBV), mean transit time (MTT), time to peak (TTP) and delay time (DLY) and dynamic 4D-CTA images. The measured region including the ischaemia side local lesions and the corresponding healthy side brain tissue perfusion parameters. The dynamic 4D-CTA images were reconstructed to show vascular stenosis site and vascular collateral circulations. The stenosis of one side middle cerebral artery in 13 cases, one side posterior cerebral artery in 3 cases. The CBF, CBV, MTT, TTP and DLY in stenosis and healthy side had statistically significant difference (p < 0.05) and the parameters were 33.9 ± 6.4 and 35.7± 6.9 ml/ (100 g •min), 2.03±0.15 and 2.11±0.18 ml/100 g, 3.88±0.66 and 3.69±0.72s, 14.43±4.20 and 13.68±4.08s, 2.09±0.85s and 1.51±0.58s. The one-stop CTP/CTA imaging technique significantly improves the accuracy and efficiency in the evaluation of cerebral arteries stenosis, infarct localisation and abnormal blood perfusion and is a perfect imaging tool for the TIA diagnosis. Comparison of high pitch (3) and standard pitch (0.6) CT angiography using 128-slice dual-source CT in patients with peripheral arterial disease K. Choo, J. Park, J. Kim, J. Roh; Busan/KR (speedsmile@hanmail.net) We investigated the effect of high-pitch (3) CT angiography with good image quality on qualitative and quantitative parameters and reduced the radiation dose in patients with peripheral arterial disease. Methods and Materials: Eighty patients were divided into two groups; the protocol was high pitch in 40 patients group and standard pitch in the other 40 patients group. For quantitative analysis we calculated the mean arterial attenuation, the mean difference between maximum and minimum attenuation values, contrast-tonoise ratio (CNR) and figure of merit (FOM). In addition, visual scores were used for qualitative evaluation. Results: There were no significant intergroup differences in mean arterial attenuation (high pitch vs. standard pitch: 428.6 ± 85.6 vs. 434.3 ± 86.9 HU) and in the mean difference between maximum and minimum attenuation (high pitch vs. standard pitch: 240.1 ± 90.0 vs. 220.1 ± 98.4 HU). Both the mean CNR and the mean FOM were not significantly different (high pitch vs. standard pitch: 27.0 ± 10.8 vs. 28.0 ± 8.6, 2.2 ± 1.96 vs. 1.5±0.8, respectively), and there was no significant intergroup difference in visual scores. The mean dose-length product was significantly lower at high pitch than at standard pitch (408.4 ± 43.4 vs. 619.8 ± 188.4.7 mGy·cm). The high-pitch protocol CT angiography with 128-slice dual-source CT allows for reduction of the radiation dose by approximately 34% versus standard pitch protocol CT angiography with 128-slice dual-source CT without deterioration of vascular enhancement and image quality. Differential diagnosis of cervical artery dissection and intra-arterial thrombosis using MRI and MRA M. Dreval, M. Krotenkova, L. Kalashnikova, L. Dobryinina, R. Konovalov; Purpose: This study aimed at exploring MRI and 3D-TOF MRA in differential diagnosis of intra-arterial thrombosis and cervical artery dissection (internal carotid artery and vertebral artery) in different periods of disease using the contrast index. A total of 40 patients with extracranial artery dissection manifested by ischaemic stroke or isolated headache (20 men, 20 woman, mean age 37.3±6.1 years) and 8 patients (5 men, 3 woman, mean age 52.4±8.8) with ischaemic stroke due to intra-arterial thrombosis were studied. Scanning protocol included 3D-TOF MRA sequence for extracranial internal and vertebral arteries and T1 fat suppression (f/s) sequence for neck in axial plane. MRT/MRA were carried in dynamics and obtained data were analysed in 6 time intervals: 1-3 days, 4-7 days, 8-14 days, 15-21 days, 22-60 days and 61-90 days. Intramural haematoma (IMH), intra artery thrombus (IAT) and m. sternocleidomastoid signal intensity was measured and contrast index calculated. Results: After statistical analysis of the data with the use of non-parametric statistical methods (Mann-Whitney U test) it was revealed that value of the contrast index of IMH was higher than that of IAT within 2-5 time interval (4 to 60 days) (p < 0.05). The contrast index did not differ significantly within first 3 days and during 3 months. The subjective visual analysis showed the same results. Conclusion: MRI sequences as T1 f/s and 3D-TOF MRA could be useful for differential diagnosis of IMH and IAT within the interval of 4 days to 2 months of the disease. Impact of organ-specific dose reduction on image quality of head and neck CT-angiography R.S. Lanzman, L. Schimmöller, P. Purpose: Assessment of coronaries on patients with high heart rate (HR) using present generation CT is challenging due to an increase of vessel motion. The purpose of this study was to evaluate the performance of a novel coronary motion compensation algorithm on patients with a HR > 60 bpm. Prospective or Retrospective CCTA scans on 15 patients with minimum HR of 60 (mean: 72) where acquired using a Discovery CT750 HD (GE Healthcare, Waukesha, WI) and reconstructed using conventional CCTA reconstruction algorithm (STD) and novel coronary motion compensation algorithm, SnapShot Freeze (SSF). Two senior cardiovascular radiologists evaluated diagnostic image quality of 13 coronary segments in a blinded manner using a 4-grade scale (1 non-diagnostic, 4 excellent). 186 coronary segments were assessed. Results: Overall number of diagnostic segments was higher using SSF compared with STD (95% vs. 85%). Overall average score of SSF reconstructed segments was significantly higher compared with STD reconstruction ( Purpose: To evaluate the feasibility and imaging quality of double prospectively ECG-triggered high-pitch spiral acquisition mode for coronary computed tomography angiography (CTCA) in patients with atrial fibrillation (AF). Methods and Materials: 47 patients (11 women, 36 men; mean age 64.5±12.1 years) were enrolled for CTCA examinations using a dual-source CT with 2×128 × 0.6 mm collimation, 0.28 s rotation time and a pitch of 3.4. Double high-pitch mode was prospectively triggered first at 60% and later at 30% of the R-R interval within two cardiac cycles. Image quality was evaluated using a four-point scale (1 = excellent, 4 = non-assessable). Results: From 672 coronary artery segments, 77.5% (521/672) was rated as score of 1, 20.8% (140/672) as score of 2, 1.2% (8/672) as score of 3 and 0.4% (3/672) was rated as 'non-assessable'. The average image quality score was 1.25±0.38 on a per segment basis. Mean dose-length product (DLP) for CTCA was 92.6±28.2 mGy·cm, the effective dose was 1.30±0.39 mSv (0.64-1.97 mSv). In patients with AF, double prospectively ECG-triggered high-pitch spiral acquisition could be a feasible and valuable scan mode for CTCA with a consistent dose below 2 mSv as well as diagnostic imaging quality. Coronary artery calcium scoring from dual-source chest CT: Purpose: To assess the concordance between ungated, high-pitch (thoracic) and ECG-gated (cardiac) examinations in the assessment of coronary artery calcium (CAC) score. Methods and Materials: 185 smokers (mean heart rate: 71.9 bpm) underwent dual-source CT examinations with acquisition of two sets of images during the same session: (a) an ungated, high-pitch scan over the entire thorax (pitch: 3.0, temporal resolution: 75 ms) (group 1); (b) a prospectively ECG-gated scan over the cardiac cavities (group 2). Two operators independently analysed the CAC load on both examinations and categorised the population according to the Agatston score. Results: The interobserver reproducibility was good for both techniques (group 1: kappa=0.90, group 2: kappa=0.89). The mean absolute values of the Agatston score did not significantly differ between groups (p=0.18). There was good reproducibility between the two techniques in classifying the population according to the commonly used cutoffs (kappa: 0.90). The ungated technique adequately categorised 172 out of the 185 patients (93); in the 13 discordant cases (13/185; 7), the ungated studies yielded lower scores than gated studies, with no more than one score category misplaced by the ungated studies. BMI and heart rates did not significantly differ between concordant and discordant scores (p=0.81, p=0.21, respectively). Differences in CAC scores between techniques were correlated to differences in the CAC scores at the level of the right coronary artery (r=0.98; p=.0001). Conclusion: Despite the mean heart rate of the studied population, a good concordance in assessing the CAC scores was found between ungated, high-pitch and ECG-gated examinations. Diagnostic accuracy of free-breathing coronary CTA using dualsource CT high-pitch acquisition: comparison of single and double scans with conventional angiography M.C. So 1 , W.L. Chin 2 , C.M. Wong 1 , C.W. Tai 1 , M.W. Leung 1 ; 1 Hong Kong/HK, 2 Singapore/SG (ninamc_so@yahoo.com.hk) Purpose: To retrospectively investigate whether two subsequent prospectively ECG-gated high-pitch CT acquisitions can increase the diagnostic accuracy of coronary CT angiography (CCTA) for free-breathing patients compared with a single acquisition and conventional angiography. Methods and Materials: Twenty-one patients (8 male, 13 female, mean age 77.2 years) with heart rates < 60 bpm unable to hold their breath underwent two immediately subsequent free-breathing CCTA scans in dual-source CT prospectively ECG-triggered high-pitch mode, followed by conventional angiography within 1 month. CCTA data and conventional angiograms were evaluated by segment by two different observers. CCTA image quality was rated on a four-point scale (1 = excellent to 4 = unevaluable) with ³50% diameter stenosis considered significant. Purpose: Radiation exposure reduction in cardiac CTA using a novel iterative reconstruction algorithm (AIDR3D) with automatic exposure control (AEC). Methods and Materials: 60 patients were examined on a 320-row detector CT (AquilionONE, Toshiba Medical Systems) using 100 kV, 8-12 cm z-axis, 350 ms acquisition time, 0.5 mm slice thickness and 320 mm FoV. Contrast medium injection was performed using a standardised protocol with 0.66 mg Iodine per kg body weight. Group 1 (G1) consisted of 30 patients (BMI=25.7±3.6 kg/m2, HF=54.9±7.4 bpm) examined using BMI adapted tube current (140-580 mA) and a FBP reconstruction algorithm in combination with advanced noise reduction filters. In group 2 (G2) 30 patients (BMI=25.7±3.7 kg/m2, HF=58.3±7.8 bpm) were examined using the novel reconstruction algorithm AIDR3D. For AEC a target noise of 33 HU was predetermined. Analysis was performed using circular regions of interests placed into the descending aorta (DA), left ventricular lumen (LV) and myocardial wall (MW). Signal-and contrast-to-noise-ratio (SNR, CNR) were calculated. Doselength-products (DLP) were recorded and effective doses were estimated. Results in G1 and G2 were compared using an unpaired t-test. Results: Both SNR and CNR differed significantly in both groups: SNR in G1 and G2 were 19.5±6.6 and 23.0±5.3, respectively, in DA (p=0.025) and 12.7±4.4 and 20.4±4.5, respectively, in LV (p < 0.001). CNR in G1 and G2 were 9.3±3.7 and 19.3±5.0, respectively (p < 0.001). Effective dose was in G2 (0.88±0.34mSv) 24% less than in G1 (1.15±0.46mSv; p < 0.011). Conclusion: AIDR3D with AEC allows for significant radiation dose reduction compared with advanced FBP reconstruction with BMI-adapted exposure. Image quality parameters in the AIDR3D group were superior to the reference group indicating further dose reduction potential. Purpose: The verbal interaction between the child and the radiographer in the radiographic examination is an unexplored, but important area of clinical practice. The aim of this study was to investigate the nature of that interaction between child and radiographer and the extent to which it varied as a function of the child's age. The participants in the study were 20 female radiographers and 32 children (3-15 years) examined for acute injuries. The verbal interactions of child and radiographer during the examination were videotaped and analysed using the Roter Interaction Analysis System (RIAS). Descriptive and non-parametric statistics were used to analyse the interaction data. The results revealed that 80% of the verbal interaction was carried out by the radiographer either to the child or to an escorting parent, while 17% was carried out by the child and 3% by the parent. Of the radiographers' communication directed to children, 78% was categorised as task-focused exchange and 22% as socio-emotional exchange. Of children's utterances, 34% was categorised as a task-focused exchange and 66% involved socio-emotional exchange. The distribution of task-focused and socio-emotional utterances varied with regard to children's age. More frequent utterances and more frequent socio-emotional exchange were found for interactions involving younger children. Conclusion: These findings reinforce the need for radiographers to be flexible and sensitive in their interactions with children and to recognise the child's individual and developmental capabilities when engaging them in radiographic procedures. Requesting x-rays at the right time to utilise the capacity of the radiology department: an everyday challenge M. Mowinckel-Nilsen; Os/NO (milh@helse-bergen.no) Purpose: Historic data shows that delayed ordering of x-rays makes it difficult to optimally utilise the capacity of the Radiology department in a small orthopaedic hospital. What could be done to improve this? Methods and Materials: A method called patient-focused redesign (developed by Leicester Royal Infirmary, adapted to Norwegian conditions by Ringerike Hospital HF) was used as a tool to find a better workflow in ordering x-rays. A multidisciplinary team was assembled, and a project outline was made with a process demarcation. The team prepared a communication plan, mapped the current workflow, had a creative phase redesigning a new workflow, and measured the situation before the new workflow was tested in the hospital. An analysis of the old and new workflow was made. Evaluation was done after the new workflow had been in place for 1.5 years; new measurements were done to see the effects of the changes in the workflow. Results: Numbers of steps in the workflow were halved, saving time for several professions. X-ray examinations not ordered on time were reduced by 76.5%. Examinations ordered a week or more before the images were taken, which is within the desired timeframe, were increased by 64.1%. Conclusion: Patient-focused redesign is a good method for finding better and more efficient workflows; it can save time, increase the exploitation ratio of the equipment, and ultimately increase the quality of the radiographic service. Discrepancies between CT and conventional angiogram results were resolved by consensus together with a third observer. Sensitivity, specificity and accuracy of single and double high-pitch scans were calculated on a per segment basis. Estimated effective radiation doses were calculated using dose length product x 0.014. Results: CCTA images were diagnostic for 86% (243/283) and 97% (276/283) of segments for single and double scans, respectively, and sensitivity, specificity and accuracy were 100%, 88%, 90% and 98%, 95%, 95%, respectively. The mean estimated effective radiation dose was 1.3mSv and 2.5mSv, respectively. In patients with heart rates ²60 bpm, free-breathing CCTA using dual source CT double scans in high-pitch acquisition mode was associated with high diagnostic accuracy for the assessment of coronary artery stenosis at a very low effective radiation dose. Author Disclosures: W.L. Chin: Employee; Siemens Medical Solutions. One beat coronary CT angiography using 640 slices multidetector CT scanner in patients with atrial fibrillation To evaluate image quality and ionising radiation doses of CT coronary angiography using 640-slices multidetector CT in patients with atrial fibrillation (AF). Methods and Materials: 28 patients that have persistent AF with median heart rate of 75 bpm underwent coronary CT angiography using 640-slices multidetector CT with adaptive iterative dose reduction system. All CT examinations were performed using a one-beat prospective gating; in patients, that presented heart rate > 65 bpm, was used a broad phase window width (30-85% of R-R). The effective dose was assessed for every patient. Coronary arteries were subdivided into 15 segments using the American Heart Association's (AHA) model. Image quality was evaluated by two expert radiologists on a workstation (Vitrea, Toshiba) using a 4-score grading system: score 1 (absence of motion artefacts), score 2 (presence of mild artefacts), score 3 (presence of moderate artefacts) and score 4 (presence of severe artefacts). Median score of both radiologist and inter-rater reliability (k coefficient) were assessed. Results: Image quality was judged excellent (score 1) in 65.4% of coronary artery segments (275/420), good (score 2) in 22.7% (95/420), fair (score 3) in 7.1% (30/420) and low (grade 4) in 4.8% (20/420). Mean effective dose was 3.35mSv (range between 1.3 and 7.9 mSv). Inter-rater reliability was excellent (k=0.85). Conclusion: High image quality and low ionising radiations effective doses demonstrate that the newest generation of CT scanner overcome the limitation at coronary CT angiography that atrial fibrillation poses so far. Influence of AIDR on accuracy of plaque characterisation and lumen assessment during CT coronary angiography A. Ursani, H. Mehrez, H. Kashani, N. Paul; Toronto, ON/CA (ali.ursani@uhn.ca) Purpose: To determine the impact of Adaptive Iterative Dose Reduction (AIDR) on accurate lumen assessment in a custom-built arterial plaque phantom. Methods and Materials: Custom-built 10 cm coronary artery phantom with 6 x 3.5 mm (G1) and 6 x 5 mm (G2) vessels, lumen stenosis 0, 30, 50, 70, 90 and 100% due to 400 HU and 800 HU plaque; and 3 x3.5 mm (G3) and 3 x 5 mm (G4) vessels with lumen stenosis 30, 50, 70% due to -60 HU and 60 HU plaque. The lumen measured +400 HU. Volume CT (vCT) was performed; spatial resolution 350 μm with low-and high-resolution kernels (FC04, FC30, FC90), 120 kVp and 150 mA. 0.5/0.35 mm axial images were reconstructed ± AIDR. In-line histography mapped average plaque CT# (HU) and average lumen CT# (HU) and vessel profile. IN was measured and image contrast (C) calculated. Results: Lumen stenosis contrast data for soft filter kernel FC04 and calcified plaque 800 HU: Without AIDR: G1:30%=894/705; 50%=910/602; 7 0 % = 7 8 4 / 5 5 0 ; 9 0 % = 6 0 0 / 4 0 0 ; G 2 : 3 0 % = 9 1 9 / 5 5 0 ; 5 0 % = 9 1 5 / 5 0 0 ; 70%=864/400;90%=413/360. With AIDR: G1: 30%=870/602; 50%=890/530; 70%=770/490; 90%=580/345. G2: 30%=900/620; 50%=898/544; 70%=856/562; 90%=400/330 AIDR improved mean contrast ~10% for calcified plaque and 15% for non-calcified plaque for all reconstructions with 30-70% luminal stenosis (paired t-test, p²0.001). AIDR improved accurate representation of 90% lumen stenosis in 3.5 mm vessels. Conclusion: AIDR improves plaque image contrast by 10-15% and visualisation of high-grade stenosis in 3.5 mm coronaries. This promises superior performance for accurate coronary plaque characterisation and lumen assessment. Results: Analysis of the results for the area under the curve (AUC) demonstrated statistically significant differences in the accuracy of fracture identification between groups (p value < 0.032), when categorised with respect to post-graduation clinical experience. Radiographers with greater and less than 3 years clinical experience scored mean Az scores of 0.737 and 0.716, respectively. A trend in increased performance and increased clinical experience was also demonstrated with a mean increase of 9.2% and 8.8% in terms of sensitivity and specificity, respectively. Conclusion: Radiographers with increased clinical experience performed the most accurately with respect to AUC, sensitivity and specificity findings. Hospital category did not influence the radiographer's performance in this investigation: university teaching centre versus large regional centre. The acceptable standard following post-graduate image interpretation training is 80-95% in terms of accuracy of skeletal fracture identification. Graduate training programmes/CPD modules in clinical decision making are recommended as is a survey on a national scale to incorporate a larger sample size. Purpose: To accurately measure the workload of radiographers and sonographers for the first time in the UK and compare them with that of consultant radiologists in a DGH. Reporting data for sonographers, radiologists and reporting radiographers at a large DGH was taken from electronic records. These were converted into an RVU score using an adapted version of the Pitman-Jones RVU system. Reporting workload was calculated by dividing the total RVU scores by the number of PA spent reporting images by members of each group. Results: There were 9 sonographers working 80.5 PA/week, 2 reporting radiographers worked 10 PA/week, and 14 consultant radiologists working 158.21 PA/ week during the period April 2010 -March 2011. Sonographer workload amounted to 1,955.9 RVU per PA per year (RVU/PA/year). Radiographer workload was to 4,277 RVU/PA/year. Crude consultant radiologist workload was 4,106 RVU/PA/ year, but they spend 42.49% of their time on non-reporting activities, giving a net score of 7,140 RVU/PA/year. The reporting radiographers and sonographers make a valuable and significant contribution dealing with the increasing radiology workload. However, radiologists are more productive per PA. Differences in pay grades makes costeffectiveness between the groups more equal. Radiographer's expectations for role development: a national survey in view of radiography students in final year of graduation C.M. Mendes, A.F.C.L. Abrantes, R.P.P. Almeida, L.P.V. Ribeiro, S.I. Rodrigues; Purpose: To investigate the role development expectations of graduate radiographers with a view to predicting the potential impact of a misalignment of these expectations on quality of the service delivery and staff retention. A self-applied questionnaire development by Williamson and Mundy (2009) in UK was validated for the Portuguese language by the backtranslation method with permission of the authors and assigned to radiography students in final year of graduation in the Portuguese health schools. A total of 84 valid questionnaires, in the Likert scale format, utilised 20 attitude questions in relation to main themes of research (expectation, valence and knowledge) and were interpreted and statistically analyzed through descriptive statistics and Spearman's rho correlation. The radiography students stated an expectation for role development opportunities with 66.7% indicating that these expectations would be realized within 2 (50.0%) and 5 (29.8%) years of graduation. A significant and strong positive correlation (r=0.791, p=0.000) between job satisfaction and expectation for role development in 5 years after graduation was seen. Farther, there were no significant differences between the health schools for the expectation, valence and knowledge. Conclusion: There is an expectation and value assigned for role development opportunities. Expectation is seen to be intrinsically linked with job satisfaction suggesting that misalignment of this would have a potentially negative impact on motivation and retention of the future radiography workforce. However, there is Risk management in computed tomography using an incident reporting system M. Antoniutti, S. Doratiotto; Treviso/IT (sdoratiotto@alice.it) Purpose: Improving the management of patient safety by adopting best management practices for the governance of the system and the corporate network. Methods and Materials: Analysis of the critical situation in the diagnostic computed tomography (CT) performed in 2009-2011 with incident reporting system (IR) using the instrument of audit and definition of improvement actions. Results: Improving actions have been taken together with a method of monitoring the most critical issues with greater severity or frequency of occurrence in the CT process. Critical areas: high number of booking errors from the radiological studies of central booking, inappropriate requests by general practitioners (GPs). Improvement action (IA): organization of the audit with GPs, the final shared document has been spread through the Internet site. High number of patients not adequately prepared for the examination (non-hydrated, non-fasting, incomplete clinical information, and incomplete filling of the informed consent form examination). IA: a letter from the chief of radiology was sent to all departments to alert that requests for CT must be sent in. Radiology correctly completed and audit with GPs. Errors found in PACS. IA: correction of PACS errors and permanent organization of audit. Conclusion: This project helped the development of effective interventions closely related to the understanding of the organization's critical work in the CT process with the need to streamline the planning CT scan of the list to avoid an incongruous workload and to give each patient the right welcome. Internal audits and permanent working groups have been proposed to actuate effective remedial actions. Is a radiographer-led immediate reporting service for emergency department referrals a cost-effective initiative? M. Hardy 1 , B. Snaith 2 ; 1 Bradford/UK, 2 Wakefield/UK (M.L. Hardy1@bradford.ac.uk) Purpose: Demand for both Emergency Department (ED) and radiology services continues to increase across the UK while simultaneously, healthcare organisations are being asked to evaluate the quality of care provided and constrain service costs. National guidance on radiograph reporting times recommends ED radiographs are reported on day of patient attendance but in practice, delays in reporting persist. This study considers whether a radiographer-led immediate reporting service for ED referrals could provide a cost-effective service improvement solution. A pragmatic multi-centre randomised controlled trial was undertaken. 1502 patients were recruited and randomly assigned to an immediate or delayed reporting arm and treated according to group assignment. Patient health gain was measured in terms of change in utilities derived from EQ-5D responses at baseline and 8-week follow-up. Resources used and the costs of an immediate reporting service were analysed at the patient level and compared to standard reporting practices. Results: 1688 radiographic examinations were performed (1502 patients). 79 discordant radiographic interpretations were identified (n=79/1688; 4.7%). Interpretive errors were significantly reduced within immediate reporting arm. No significant difference was noted in the relative improvement in patient perceived health status between the 2 arms of the study. The average cost saving per patient in the immediate reporting arm £23.40. Conclusion: Radiographer-led immediate reporting of ED radiographs is a cost-effective service development and its universal introduction could make a significant contribution to the current drive to increase service productivity within current budget constraints. An investigation into the ability of Irish radiographers: in the identification of wrist and scaphoid fractures A.P. Tyrrell 1 , L. Rainford 2 ; 1 Kilkenny/IE, 2 Dublin/IE (louise.rainford@ucd.ie) Purpose: To investigate the ability of Irish radiographers in identifying and locating wrist/scaphoid fractures, to add to the evidence base for role expansion. In total, 25 radiographers across two university teaching and two large regional hospitals in Ireland participated. The computer application Ziltron demonstrated 71 plain film wrist radiographs in a Free-Response Operating Characteristic (FROC) study. The data set contained 35 abnormal images (fracture (s) present) and 36 normal (non-fracture). "Truth" was determined by the Radiology report. Fracture were categorised: obvious to subtle. Statistical analysis was performed by JAFROC application. Friday provides insight into the influence of technology on the professional development and practice in this field. In August 2011, a postal questionnaire was distributed to 521 hospital sites across the UK operating both a radiography and trauma service. Information was sought relating to: the type of trauma and radiography service operated; details of the RADS operated, including education and audit to support radiographer participation; the mandatory/voluntary status of the RADS; and the imaging technology operating within the organization. Results: A total of 328 (n=328/521; 63.0%) responses were received within the defined timeframe. Analysis of the data is ongoing but will include a descriptive summary of current practice across the UK with regard to "red dot", commenting and reporting by radiographers and assessment of the impact on the implementation of digital imaging technology across the UK on service levels compared to an earlier survey undertaken in 2007. Conclusion: Radiographer contribution to the interpretation of trauma images is an expectation of UK radiographer practice. Whether the profession has moved forward in its readiness to progress beyond "red dot" and embrace commenting is yet to be seen and this presentation will provide an insight into practice boundaries and variations that exist. 14:00 Purpose: Diagnostic value of dynamic contrast-enhanced perfusion MRI in detection and characterisation of endometrial cancer, correlated with tumour grading, being the histopathological analysis as the standard of reference. A total of 80 patients with histologically proven endometrial carcinoma underwent a dedicated pelvic MRI examination (1.5 T system, Achieva, Philips), using high-resolution pelvic phased array multicoil. Each patient scan a lack of social recognition of the radiographer, suggesting the need to promote measures to increase the profession recognition. Job satisfaction among radiographers in Switzerland: a national survey N. Richli Meystre, P. Lehmann, N. Mamboury; Lausanne/CH (nicole.richli@hesav.ch) Purpose: The technological improvements in radiology over the past decade have resulted in an important rise in demands for radiological examinations and treatments. An increasing number of well qualified radiographers are needed and healthcare authorities are worried about the growing shortage of radiographers. Job (in)satisfaction has been highlighted as a contributing factor to turnover, respectively, to long-time retention. The aim of this survey was to appreciate workplace conditions and job satisfaction among radiographers. Methods and Materials: All radiographers working in Switzerland were invited to participate with an online questionnaire. Different factors contributing to job satisfaction were scored from -2 (very unsatisfied) up to +2 (very satisfied). Results: 753 radiographers completed the questionnaire. The response rate is estimated at 26%. 62% are working in diagnostic, 23 % in nuclear medicine and 15% in radiooncology. 37% are working for more than 10 years in the same place. The overall job satisfaction level was scored at 0.66. The highest levels were reached for the diversity of job activities (+1.19), the quality of radiology facilities (+ 1.16), teamworking (+1.03) and autonomy (+1.03). The lowest levels were reached for collaboration with radiologists (+0.23), salary (+ 0.17) and career opportunities (0). Conclusion: Radiographers in Switzerland are rather satisfied about their job and the workplace conditions. In order to avoid shortage, efforts should be taken to increase the number of radiographer students and in supporting returnees. Jobenrichment measures are seen as a necessity for retention in a profession with low career opportunities. Progression of quality improvement works in radiography by radiographers R. Gullien, J.G. Andersen, A.E. Haakull; Oslo/NO (uxraul@ous-hf.no) Purpose: To visualise the ongoing progression over years in quality improvement work in radiography by radiographers and share our experiences. Methods and Materials: 1) As a basis through the entire improvement work, the National Quality Assurance Manual (QAM) that specifies how to measure the quality assurance work was used. 2) Practiced the method in the department as basic measurement individual and overall measurements (static/snapshot). 3) Individual and overall measurements recorded several times over a period to see changes (dynamics/moving range) (local). 4) Implemented targeted improvements. 5) Measured inter-variability among the quality control (QC) radiographers. 6) Training the QC radiographers to avoid differences between them. 7) National meeting with representatives from all counties (national). 8) Comparison across the counties and input to the audit of the QAM. 9) Cooperation with hospital outside Norway, benchmarking the system, comparison across countries (international). Results: Radiographers were trained by self-assessment: their knowledge was updated, their skills were developed, their attitude to regular audit was changed and improved, their own performances against international and national standard and objectives were reviewed. Targeted initiatives against unacceptable variances in performance are necessary. Time set aside to allow radiographic quality assurance work, analysing, evaluating and act accordingly. QC radiographers have the responsibility of ensuring the essential quality improvement and assurance work. Conclusion: Progression is from snapshot/static to dynamics/moving range, from general to focused measures, from local to national, from national to international. Quality improvements became more and more complex over time. Advancements and developments are important in addition to the continuous implementation of basic training and instructions. Radiographer contribution to the interpretation of trauma radiographs: a survey of UK practice B. Snaith 1 , M. Hardy 2 , E. Lewis 1 ; 1 Wakefield/UK, 2 Bradford/UK (bev.snaith@midyorks.nhs.uk) Purpose: Radiographer abnormality detection schemes (RADS) were introduced in the UK in the mid-1980s with the development of the "red dot scheme". This presentation reports the findings of a new survey and establishes the current position of RADS (including "red dot", commenting and reporting) across the UK and was with the obturator in 12 cases and with the internal pudendal in one case. The angle of origin of the uterine artery on the right side showed a mean of 53.2° (SD: 25.23, range: 0°-98°). On the left side the angle showed a mean value of 54.8° (SD: 17.72, range: 19°-91°). The uterine artery arises typically directly from the IIA anterior division. Atypical origins like origin from the IIA main stem or from the IIA posterior division should be searched for when the artery could not be found in its typical location. Fibre tracking evaluation of sacral nervous pathways 3D architecture in women affected by endometriosis M. Sergi, V. Vinci, S. Bernardo, P. Sollazzo, M. Saldari, L. Manganaro; Rome/IT (mariaeleonora.sergi@gmail.com) Purpose: To evaluate feasibility of tractography to study sacral nerves in women affected by pelvic endometriosis. We enrolled 2 groups of patient: 25 women with US diagnosis of endometriosis and a control-group of 10 women. With 3 T MRI, we reconstructed nervous pathway postprocessing DTI images. We analysed 2 main parameters: 3D architecture of nervous pathways and fractional anisotropy values (FA). We analysed fibres length and branches morphology, thereafter we assigned to each a range of values obtaining 3 main classes of pathways: 1 st class (normality, 3-4), 2 nd class (mild alteration, 5-6) and 3 rd class (severe alteration, 7-8). Results: Analysing 3D nervous pathways, we obtained a homogeneous distribution of the control group (10pt) in the first class (normal pathways). All cases of endometriosis of the posterior compartments (18/25 patients) presented an abnormal pathway (3 rd class), while remaining cases with anterior-medial localisation were equally distributed in 1 st and 2 nd class. We obtained low FA values in both groups; however, in case-control group range values were included between 0.47 and 0.34 while in patient groups FA values were lower between 0.36 and 0.24. Conclusion: Fibre tracking allowed a complete evaluation of the female pelvis defining the global situation of the patient and leastly formulating a potential explanation to symptoms. Fibrotic reaction, adhesions and nerves growth stimulation factors may explain both of the altered branch morphology and the lower FA values. We suggest tractography as a complementary tool for the female pelvis study, representing the only non-invasive way to study nervous pathways. Purpose: To verify whether MRI accuracy in diagnosing deep infiltrating colorectal endometriosis (DICE) can be improved using an association of two selected findings. Laparoscopy or histopathology was taken as the gold standard. Methods and Materials: Imaging database of our Institute was retrospectively reviewed. T2-weighted MR images were evaluated by two experienced radiologists using two criteria. First, not thickened or thickened intestinal wall surrounded by fat-plane interface represents a normal result; nodules/hypointense plaque-like lesions in the adjacent fat-plane joint to thickened intestinal wall are considered an abnormal result. Second, not thickened or thickened intestinal wall surrounded or not by fat-plane interface represents a normal result; nodules/hypointense plaque-like lesions in the adjacent fat-plane joint to thickened intestinal wall showing "radiating retracting shape" are considered an abnormal result. A third radiologist looked in medical history for laparoscopy and histopathology. MRI results were compared with laparoscopy or histopathology findings by 2 x 2 tables and were statistically analysed (K statistics). .30 years) with clear symptoms attributable to pelvic floor dysfunction. All patients were given a questionnaire designed to obtain physiological data (age, gender, BMI) and pathological (diabetes, comorbidities, previous pelvic surgery). The MRI provided a morphological study with T2-weighted sequences in the axial sagittal and coronal plane and an Cinematic FIESTA (Fast Imaging Employing Steady-State Acquisition) in the sagittal plane at rest and during the phase of maximum straining, to measure the line pubo-coccygeal (PCL), the line H (pelvis diastasis) and the M (lower pelvis). Results: BMI correlated significantly with H (p = 0.037) and PCL (p = 0.026), while age correlated with H (p = 0.009) and M (p = 0.004). The parity but not the number of children causes a significant increase in pelvic lowering (p = 0.038) as well as previous pelvic surgery (p = 0.038). The pathophysiological changes are predictive of morphometric parameters obtained with MRI. Because of its fast acquisition a cinematic sequence could be advisable in all study protocols of female pelvis. Origin of the uterine artery in females using three-dimensional reconstructed contrast-enhanced MR angiography before uterine Purpose: To describe the patterns of origin of the uterine artery from the internal iliac artery (IIA) before uterine artery embolisation (UAE) using three-dimensional (3D) reconstructed contrast-enhanced MR angiography (CE-MRA). The study was retrospectively performed on 84 females (mean age 45.5 year). Pre-embolisation CE-MRA was performed before UAE. 3D images were reconstructed using Syngo-VesselView application. For each uterine artery the point of origin was identified and the angle which the artery makes with its main stem of origin was calculated. The uterine artery was detected in 165 (98.2%) of the 168 (84 patients) arteries. The artery originated directly from the IIA anterior division in 141 arteries of the detected arteries (85.5%), from the IIA bifurcation point in 7 arteries (4.2%), from the IIA main stem in 3 arteries (1.8%) and 1 uterine artery (0.6%) originated from the IIA posterior division. The uterine artery originated indirectly from the anterior division with a common segment in 13 arteries (7.9%). The common origin Friday measured on the MR console and compared among positions. The obstetric conjugate and the sagittal inlet and outlet were both assessed in the midsagittal plane. Results: MR pelvimetry in the different positions proved feasible in all subjects, yielding diagnostic quality images in every volunteer and pregnant woman, although the hand-to-knee positions were found difficult to maintain. In the hand-to-knee position, pelvic inlet reduced from 13.3 cm to 13.0 cm and obstetric conjugate from 12.6 cm to 12.3 cm. In contrast, sagittal midpelvic diameter enlarged from 13.3 cm to 13.6 cm, pelvic outlet anteroposterior diameter from 11.5 to 12.0 cm and sagittal pelvic outlet diameter from 8.7 cm to 9.1 cm. Our results showed that a hand-to-knee birthing position expands sagittal midpelvic diameter, pelvic outlet anteroposterior diameter and sagittal pelvic outlet diameter, suggesting facilitation of labour and delivery. Retrospective analysis of elements that can predict short-and longterm outcome in patients affected by uterine leiomyomas and treated with MRgFUS Purpose: To retrospectively evaluate predictive factors to obtain an optimal treatment of uterine fibroids treated using Magnetic Resonance guided Focused Ultrasound (MRgFUS). Methods and Materials: 68 fibroids (52±18 mm) in 55 symptomatic women (age average 40±5) were treated using MRgFUS (ExAblate 2100) combined with a 3 T MR unit (GE). T2 SI and T1 SI of fibroids were measured on pre-treatment examination before and after administration of gadolinium (Gd-BOPTA, Bracco); also the distance between centre of myoma and skin, skin thickness, maximum diameter and volume of fibroids were recorded. The day of treatment the non-perfused volume (NPV) was recorded at the end of the treatment. It was considered treatment time in terms of energy (J) used and duration of single sonication. All parameters were related to final NPV and volume shrinkage at 12 months to established short-and long-term results of treatment. Results: Difference between T1 SI of the fibroids and healthy myometrium significantly correlates with volume shrinkage (45%) and NPV (60%, r=0.85). T2 SI on pre-treatment studies, distance between skin surface and centre of myoma (53±19 mm) and skin thickness (13±7 mm) show a mild correlation with volume reduction at 12 months (36+18 mm, respectively r=-72.5 p=0.047 and r=69.7 p=0.03).Moreover, there was positive correlation between measured parameters, sonication duration and energy necessary to obtain a > 50% NPV (70±15%, r= 62.8, p=0.021). Conclusion: SI ratio on T1w of uterine fibroids and myometrium on screening MRI should be considered as predictor of positive outcome for MRgFUS treatment. 14:00 Purpose: We evaluated feasibility of 3 T system in the detection of endometriosis implants in the Douglas Pouch, in order to offer a precise preoperative diagnosis of deep infiltrative endometriosis involving this particular region. Methods and Materials: From October 2010 and April 2011, we enrolled 19 women coming with either ultrasound or anamnestic suspect of endometriosis. Pelvic MRI examination was performed on 3 T system. We theoretically divided female pelvis in three compartments and concentrated on the posterior one, evaluating, in particular, the uterosacral ligaments and the specific signs of posterior cul-de-sac obliteration. Results: MRI diagnosed posterior cul-de-sac obliteration in 15/19 patients. We detected in 5/15 cases nodular endometriosis implants in PCS; signs of fibrotic plaque on the uterine serosal surface were identified in 4/15 cases; 3/15 cases showed a tethered appearance of the rectum, 6/15 cases presented an elevation of the posterior vaginal fornix. In 3/15 cases strands between uterus and intestine was clearly depictable, at last, involvement of utero-sacral ligaments (USLs) and signs of utero-sacral ligaments involvement were identified in 6/15 cases. Moreover, glandular-like collection localised behind uterus was identified in 7/15 cases. MRI findings were compared with laparoscopy, thus obtaining a sensitivity value of 93%, and specificity value of 75% Conclusion: Precise preoperative mapping of posterior cul-de-sac region is essential for a preoperative planning. In our work 3 T MRI revealed excellent in the evaluation of posterior cul-de-sac obliteration associated with an optimal evaluation of the utero-sacral ligaments, due to the higher contrast spatial resolution. Diffusion-weighted magnetic resonance imaging of the female pelvis: do apparent diffusion coefficient values of the fat tissue change over the menstrual phases? Purpose: To establish whether the apparent diffusion coefficient (ADC) measured with DWI in the pelvic fat tissue of healthy reproductive-age women significantly varies from the proliferative to the periovulatory phase of the menstrual cycle. Methods and Materials: 27 women (18-40 years) , not assuming oral contraceptives nor referring any vaginal discharge or abnormalities of their menstrual cycles, underwent pelvic DWI (1.5 T, 8-channel coil, sagittal scans, b values: 0 and 800 mm/sec2) both at the 5 th day after the beginning of the menstruation and repeatedly every day in the periovulatory phase; among these latter examinations, the one corresponding to the 14 th day before the subsequent cycle was retrospectively selected. An ADC value resulting from the average of three measurements obtained at slightly different position was calculated for each examination within a circularshaped, 4-mm diameter region of interest totally included in the adipose tissue of the ischiorectal fossa. The statistical significance of the differences between the ADC values measured in the two menstrual phases was determined using the Student's t-test per paired data. The ADC values measured in the pelvic adipose tissue in the proliferative phase of the menstrual cycle (mean: 0.765 mm2/sec, range: 0.26-1.26) were higher than those obtained in the periovulatory phase (mean: 0.558 mm2/sec, range: 0.24-0.89). The difference was highly significant at statistical analysis (p < 0.001). The ADC values measured with DWI in the pelvic adipose tissue of healthy reproductive-age women are significantly higher during the proliferative than in the periovulatory phase of the menstrual cycle. Purpose: To evaluate Alzheimer's disease premature diagnosis based on spectroscopy MRI. We carried out a prospective study on 178 patients (116 women and 62 men) whose ages ranged 27 to 68 years (mean age 65 ± 12). Every patient presented mild or moderate cognitive impairment according to Reisberg score (3-4 grade). Standard brain MR and spectroscopy brain MR were performed using a 3 T intensity MRI device (Archieva TX, Philips Healthcare, Best, The Netherlands). Spectroscopy MR was focused in posterior parietal and frontal lobes gray substance using a unique volume (20 x 20 x 15 mm) and two different echotimes, TE (32 and 136). Morphology and volume of temporal lobes were evaluated through FLAIR coronal images which were used to quantify temporal horn width and so classify patients in four groups. JMRUI (Java Magnetic Resonance User Interface) was used to calculate quantitative parameters in MR spectroscopy. MR was used to measure: calculation of NAA (N-acetyl aspartate), Cr (creatinine), Cho (choline) and mI (myo-inositol) metabolites ratios. We used analysis of variance to compare metabolite ratios between the different patient groups previously defined. Results: We found significant differences (p ² 0.05) between groups in NAA/Cho concentration (p=0.022), both in long and in short eco times and frontal and parietal anatomical regions. No other significant differences between groups were found. Conclusion: MR spectroscopy could increase efficiency in Alzheimer's disease premature diagnosis as well as turning out to be a useful additional tool for the clinician next to clinical history. Differentiating multiple system atrophy and Parkinson's disease on 3 T MRI: a novel use of decision tree S. Rajandran Nair, L.K. Tan, N. Ramli, S.Y. Lim, K. Rahmat, H. Mohd Nor; Kuala Lumpur/MY Purpose: Differentiation of multiple system atrophy (MSA) and Parkinson's disease (PD) remains a clinical challenge. The purpose of this study was to develop a decision tree using parameters obtained from standard MRI and diffusion tensor imaging (DTI) to distinguish these clinical entities. We performed standard MRI brain and DTI at 3.0 T on 26 PD and 13 MSA patients. Linear, volumetry and DTI (fractional anisotropy, FA and mean diffusivity, MD) of putamen, substantia nigra, pons, middle cerebellar peduncles (MCP) and cerebellum were measured. A three-node decision tree was developed, with the aim of 100% specificity at node 1, 100% sensitivity at node 2 and highest combined sensitivity and specificity at node 3. Results: Mean MCP width, anteroposterior diameter of pons and mean FA MCP with cut-off values of 14.6 mm, 21.8 mm and 0.55 respectively, were selected for the decision tree from nine parameters (mean width, FA and MD of MCP; anteroposterior diameter of pons; cerebellar FA and volume; pons and mean putamen volume; mean FA substantia nigra compacta-rostral) that showed statistically significant (P < 0.05) differences between MSA and PD. The decision tree accurately classified 12 out of 13 MSA patients with an overall 92% sensitivity, 96% specificity, 92% PPV and 96% NPV. The decision tree could be used as a diagnostic algorithm in the differentiation of MSA and PD. Subthalamic nuclei 3 Tesla T2-relaxometry correlated to UPDRS scores in pre-deep brain stimulation ( Purpose: Degeneration within the subthalamic nucleus (STN) in Parkinson's disease (PD) is a potential marker for targeting DBS. We aimed to investigate whether pre-and postoperative Unified Parkinson's Disease Rating Scale (UPDRS) scores are related to T2 relaxation (T2r) of the STN and whether there is a correlation of laterality between clinical assessment and T2r. Methods and Materials: 12 patients and 14 controls were examined at 3 Tesla by a multicontrast spinecho sequence. STN and control volumes relaxation times were analysed UPDRS scores were determined during "on" and "off" pre-and postoperatively. follow-up checks (median 3 years) 15 subjects had stable disease (SD), 20 had progression of disease (PD) and 16 developed AD. Baseline metabolic ratios (1H MRS) between the 3 groups of patients indicated significant differences in the left frontal lobe in mI/H20 ratio, between patients with SD (0.27) and DP (0.22) (P = 0.03). In groups of patients with DP and AD there was a significant difference in NAA/Cr (1.77 vs. 1.43), (P = 0.02). Conclusion: MI and NAA seem to be very sensitive biomarkers for conversion from MCI to AD. The significance of our metabolic ratio results needs further study. Purpose: Uric acid has been associated with focal vascular brain disease such as lacunar infarcts and white matter lesions. However, it is unknown whether uric acid also relates to global brain changes such as brain atrophy. We therefore studied the relation of uric acid with brain atrophy and whether this is coupled with worse cognitive function. In 814 persons of the population-based Rotterdam study (mean age 62.0 years), we studied the relation of uric acid levels with brain tissue atrophy and cognition, using linear regression models, adjusted for age, sex and putative confounders. Brain atrophy was assessed using automated processing of MRI. Cognition was assessed using a validated neuropsychological test-battery and we computed compound scores of cognitive domains. Results: Higher uric acid levels were associated with white matter atrophy (difference in Z-score of white matter volume per standard deviation increase in uric acid: -0.07 (95% confidence interval: -0.12; -0.01)). This was particularly marked when comparing hyperuricaemic to normo-uricaemic persons (Z-score difference: -0.27 (-0.43; -0.11)). Worse cognition was primarily found in persons with hyperuricaemia (-0.28 (-0.48; -0.08)). Conclusion: Hyperuricaemia is related to white matter atrophy and worse cognition. The neural correlates of anomia in the conversion from mild cognitive impairment to Alzheimer's disease E. Pravata' 1 , J. Tavernier Purpose: Language impairment is frequently observed in patients with Alzheimer's disease (AD; in this study, we investigated the extent and distribution of brain atrophy in subjects with conversion from mild cognitive impairment (MCI) to AD with and without naming difficulties. Methods and Materials: This study was approved by the Institutional Review Board and was HIPAA compliant. All subjects or their legal representatives gave informed consent for participation. Ninety-one subjects from the Alzheimer's disease neuroimaging initiative (ADNI) with (N=51) and without (N=40) naming impairment as per the Boston naming test (BNT) underwent brain magnetic resonance (MR) imaging 12 months before and at AD diagnosis. Structural MR images were processed using voxel-based morphometry. Longitudinal and cross-sectional comparisons between groups were performed to assess differences in gray matter (GM) loss patterns. Results: During the 12-month prior to diagnosis, AD patients with naming difficulties showed distinct areas of greater GM loss in the temporal lobes, cingulate gyri, and precunei than patients without naming difficulties. GM volume in the left fusiform gyrus (Brodmann area 20) was greater in patients without naming impairment. This study provided evidence of distinct patterns and dynamics of brain atrophy in AD patients with naming difficulties when compared with those with intact language, as early as 12 months prior to AD diagnosis. Language deficits and their neuroanatomical correlates should be taken into account in the design of a structural imaging biomarker for the early detection of AD. Gender differences in grey matter atrophy patterns in the mild cognitive and early Alzheimer's disease M. Spampinato 1 , E. Pravata' 1 , B. Langdon 1 , K. Patrick 1 , R. Parker 2 ; 1 Charleston, SC/US, 2 Gainesville, FL/US (emanuele.pravata@gmail.com) Purpose: To investigate gender-specific differences in grey matter (GM) volume loss patterns in amnestic mild cognitive impairment (aMCI) patients with and without progression to Alzheimer's disease (AD) using MR voxel-based morphometry (VBM). We included 186 aMCI patients (128 males, 58 females; age 77±7 years), with (N = 91) and without (N = 95) conversion to AD, from the Alzheimer's disease neuroimaging initiative (ADNI) cohort. Three-dimensional MPRAGE brain scans obtained one year before conversion from aMCI to AD and at AD diagnosis were available. The general linear model was performed to evaluate for differences over time in cognitive decline from the clinical dementia rating (CDR) scale. Optimised VBM with SPM8 was used to assess GM volume differences by performing cross-sectional and longitudinal group comparisons with two-sample and paired t-tests. Results: Both male and female AD converters showed significant cognitive decline at CDR (p < 0.001). Total GM volumes significantly differed between all groups of males and females (p < 0.01). Compared to stable aMCI, male AD converters showed atrophy progression one year prior to AD diagnosis in the limbic, temporal, parietal, frontal, insular lobes and deep gray nuclei, while female AD converters showed only one area of significant GM loss in the right uncus (p < 0.05 FWE-corrected). The extent and distribution of regional GM volume loss in aMCI to AD converters is strongly influenced by the gender. This finding has potential implications for therapeutic approaches in AD and should be taken into account in clinical trials. Purpose: Excessive daytime sleepiness (EDS) is an important non-motor symptom of Parkinson's disease (PD). The underlying neuropathological mechanism accounting for EDS is not well understood. The purpose of the present study was to determine regional grey matter (GM) volume changes in PD patients with EDS. Scale ESS ³ 12) (EDS-PD), 17 age and disease duration-matched PD patients (Epworth Sleepiness Scale ESS ² 6) and 17 age-matched healthy controls were enrolled in the study. The χ 2 and Student's t tests were used to test for differences in demographic and clinical characteristics between groups. Differences in GM volume between groups were evaluated by applying the voxel-based morphometry (VBM) method. Results: Total calculated levodopa equivalent dose was higher in EDS-PD when compared to PD patients (p < 0.05). Comparison of EDS-PD with PD patients and controls showed increased GM volume bilaterally in the hippocampus, the parahippocampal gyrus, the fusiform gyrus and in cortical areas in the temporal, frontal and parietal lobes (p < 0.001). Conclusion: EDS-PD patients present increased regional GM volume in the mesolimbic/mesocortical dopamine pathway, which is activated during sleep. Drug-induced GM volume increase through a process of neuronal plasticity may represent the underlying mechanism. Purpose: Olfactory dysfunction is the second most frequent feature of PD, occurring in 70-90% of patients. Recent studies suggest that the olfactory system is among the earliest brain regions involved in PD. Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) consent quantitative measures of the microstructural integrity of nuclei and fibre tracts. Our aim was to assess fractional anisotropy (FA) changes of the olfactory tract in early PD patients (Hoehn ed Yahr stage 1-2.5) and to correlate FA values with the clinical score of the olfactory deficits Methods and Materials: A case control study was conducted on 15 PD patients responding to UK PD Society Brain Bank for probable PD and 13 healthy controls that underwent MRI (1.5T, Avanto, Siemens, Erlangen, Germany). We performed T1 weighted MPRAGE, T2 and PD weighted TSE and EPI (on 12 non-collinear directions at b0 and 1000s/mm2 to assess DTI) sequences. FA was computed with standard formulas. All subjects underwent UPSIT (University of Pennsylvania Smell Identification Test) Results: We found a significant difference between FA values of the gyrum rectum subcortical white matter of PD patients and healthy controls (0.27± vs. 0.39±; p < 0.05). A significant difference was also found in UPSIT values between the two groups (p < 0.05). Our results suggest that early olfactory dysfunction in patients with PD may be a primary consequence of damage to the olfactory tract. Diffusion tensor Imaging reaches the diagnostic sensitivity to assess early olfactory dysfunction in PD patients Quantitative evaluation of myocardial perfusion reserve at 3 and 1.5 Tesla in comparison to invasive measurement of fractional flow reserve for detection of coronary artery disease T. Walcher, K. Ikuye, W. Rottbauer, J. Woehrle, P. Bernhardt; Ulm/ DE (peter.bernhardt@uniklinik-ulm.de) Purpose: Fractional flow reserve (FFR) is considered as the standard invasive diagnostic tool to determine haemodynamic significance of coronary artery disease (CAD). Adenosine-perfusion cardiac magnetic resonance imaging (CMR) at 1.5 and 3 Tesla has been proven to be capable to noninvasively determine myocardial perfusion reserve, but has not been compared against each other and validated against FFR as standard reference. Methods and Materials: 34 patients (62.0 ± 10.9 years) with suspected CAD were included into the study. All patients were scanned at both field strengths, 1.5 and 3 Tesla, including adenosine and rest perfusion imaging. Coronary x-ray angiography including FFR measurement in the left anterior descending (LAD), circumflex (CX) and right coronary artery (RCA) was then performed in all patients. Myocardial perfusion reserve was calculated in 544 myocardial segments for each field strength and compared to the FFR measurement of the supplying coronary artery. FFR ²0.8 was regarded as relevantly reduced. In 38 coronary arteries (19 LAD, 8 CX, 11 RCA) a FFR ²0.8 was found. Receiver operator curve analysis yielded higher area under the curve for 3 T in comparison to 1.5 T CMR (0.963 vs. 0.645, p < 0.001) resulting in higher sensitivity (0.91 vs. 0.62) and specificity (1.0 vs. 0.77). Conclusion: Quantitative evaluation of myocardial perfusion reserve at 3 and 1.5 Tesla is capable to detect haemodynamic significance of coronary artery stenosis. In our cohort, the diagnostic accuracy at 3 T seems to be superior to 1.5 T. Dynamic stress computed tomography perfusion imaging for the detection of functionally significant coronary lesions Purpose: To evaluate the performance of hyperaemic myocardial blood flow (MBF) derived from stress computed tomography perfusion (CTP) imaging in the detection of functionally significant coronary lesions defined by fractional flow reserve (FFR) ²0.75 in a prospective cohort of patients with stable chest pain. Coronary computed tomography angiography (CTCA) and CTP were performed in 50 patients (35 males/15 females; mean age 58±9 years) referred to invasive angiography. A second-generation dual-source CT scanner (Somatom Definition Flash, Siemens) with a dynamic ECG-triggered axial shuttle mode was used. This technique provides an arterial input function and myocardial time-attenuation curves fitted to a 2-compartment model to give MBF. Hyperaemia was induced by infusion of adenosine (140µg/kg body weight). Three to 4 minutes into the infusion, 60 ml of contrast were injected. Gantry rotation time was 285 ms, collimation 64x0.6 mm, tube voltage 100 kV and the tube current-time product was 300 mAs/rotation. Purpose: The use of CT-scans in assessment of coronary artery disease is rapidly growing. More selective referral of stable angina patients with intermediate probability of coronary artery disease (CAD) to CT coronary angiography (CTCA) may temper the health care spending on cardiac CT-scans. The value of updated algorithms using "in-office-evaluation" and calcium score (CaSc) is investigated. We evaluated retrospectively 2042 symptomatic stable angina patients who underwent "in-office-evaluation", unenhanced CT-scan for calculation of CaSc and CTCA. Outcome of our study was non-invasive diagnosis of obstructive CAD (³50% lumen diameter narrowing) by CTCA. Two algorithms were developed. First algorithm used "in-office-evaluation" consisting of chest pain typicality, sex, age, risk factors and ECG. The second algorithm used both "in-office-evaluation" and CaSc. Discrimination of both models was tested using the area under the ROC curves (AUC). Patients were classified to low (< 10%), intermediate (10-90%) and high pre-test probability (³90%) of obstructive CAD. Testing with CaSc or CTCA was deemed appropriate in patients intermediate probability of CAD. Net reclassification improvement (NRI) of algorithm 2 was calculated in patients with intermediate probability of CAD according to algorithm 1. Results: Discrimination of CAD was significantly higher using algorithm 2 compared with algorithm 1 (AUC: 0.90 vs. 0.80, respectively). The "in-office-evaluation" algorithm reduced both unenhanced CT-scan and CTCA by 12%. An additional 32% of CTCA-scan was reduced using algorithm 2 subsequently with NRI of 66%. Conclusion: Updated algorithms using both "in-office-evaluation" and CaSc may reduce referral of stable angina patients to CTCA by 44%. Dynamic CT perfusion imaging for the detection of myocardial ischaemia: a first experience with a 3D semi-automated evaluation software U. Ebersberger 1 , R.P. Marcus 2 , U.J. Schoepf 1 , P. Blanke 1 , Y. Wang 3 , L. Geyer 1 , A. Purpose: To evaluate the performance of a 3D semi-automated evaluation software for its accuracy and time saving potential for CT perfusion myocardial blood flow (MBF) and blood volume (MBV) assessments compared to manual evaluation as well as to SPECT. Methods and Materials: 37 dynamic, time-resolved myocardial perfusion CT datasets acquired using a dual-source CT system (Somatom Definition Flash, Siemens Healthcare, Forchheim, Germany) were assessed both manually and by use of the semi-automated prototype for MBF and MBV, based on the AHA 16-segment model. Time required for each assessment was recorded. Results were compared to SPECT as the standard of reference. Results: 592 segments were evaluated. 19 (3.21%) were excluded due to insufficient coverage. A comparison of MBF and MBV measurements using the prototype versus manual assessment showed high correlation (Spearman's rank correlation coefficient = 0.85/0.83, p < 0.0001). Mean evaluation time for MBF and MBV analysis was 49.1 ±11.2 minutes with manual assessment and 16.5 ± 3.7 minutes with the use of the prototype (p < 0.001). Conclusion: 3D semi-automated assessment of dynamic myocardial perfusion CT highly correlates with manual assessment. Significantly decreased assessment time appears promising for the integration of myocardial perfusion CT in clinical workflows. Friday protocol (ADP): clinical examination, MDCT-CA; the positive cases were recovered and underwent CA. If MDCT-CA was negative for significant CAD the patient was dismissed from the ED and taken under follow-up for 2 years. The costs of every protocol and the amount of costs for individual methods were calculated. Based on the results, the two diagnostic paths were compared about cost/effectiveness ratio. Results: At TIMI score only 30% of the patients resulted with high risk, whereas MDCT-CA was judged positive in 40% of the cases. MDCT-CA compared to CA revealed an accuracy of 97.8%, PPV and NPV were 99% and 100%. The ADP revealed lower costs than the protocol with only hospitalization (11645€ against 5322€), and showed better cost/effectiveness ratio. At 2-year follow-up 99.3% of the patients resulted well being. The ADP can help better than TIMI score to rule out patients with undifferentiated chest pain. Moreover, cost analysis demonstrated a better cost effectiveness ratio in comparison to the hospitalization, also confirmed with a long-term follow-up. Purpose: Transient ischaemic dilation (TID) in the setting of abnormal SPECT myocardial perfusion imaging (MPI) has been linked with increased cardiovascular risk. However, the significance of TID in the setting of an otherwise normal MPI study has not been clearly established. Coronary computed tomography angiography (cCTA) was utilised to evaluate the prevalence of atherosclerotic lesions and the severity of coronary stenosis in patients with TID with or without associated myocardial perfusion defects on SPECT-MPI. The study population consisted of 1553 patients who had undergone both cCTA and stress/rest cardiac SPECT. In patients with TID coronary CTA was used to evaluate each coronary segment for the presence and composition of atherosclerotic plaque and the degree of coronary stenosis. Findings were compared with a 2:1 matched-pair control cohort without TID. Results: TID was identified in a total of 30 patients from a screening population of 1553 consecutively imaged patients. Findings demonstrated that compared to TID negative risk-factor matched controls (n=60), TID positive patients had no significant differences in the presence and extent of atherosclerosis or the degree of coronary artery stenosis as evaluated by cCTA. Similarly, there were no significant differences in cCTA measures of coronary artery disease (CAD) in TID positive patients with normal perfusion compared to TID negative patient with a normal perfusion study (n=48). These results suggest that the presence of TID with an otherwise normal SPECT study does not reliably predict an increased risk for or the extent and severity of coronary artery disease. -89] ) underwent WB-CTA (64x0.6 mm) with an adapted contrast injection protocol (Iomeprol-400, 400 mgI/ml; 70+50 ml@4 ml/s). Coronary arteries were divided into 15 segments and the extra-coronary arteries into 32 segments, detected stenoses were graded using a 5-point scale. An atherosclerosis burden score (ABS) was generated for each individual and correlated to traditional CV (Framingham risk index; FRI). ABS and FRI were compared using Kaplan-Meier analysis, ROC analysis and stepwise multivariable Cox regression models. Results: At baseline mean ABS was 19.5±20.1 and mean FRI was 12±10.7; 64.5±11.3m after WB-CTA all patients received an interview to determine health status. According to Kaplan-Meier curves, mean event-free time was of 62.3±2.4m for ABS< 10, 57.6±1.9m for 10 5 mm, distance to neurovascular structures at least 3 mm, potential access, absence of articular involvement and planned cryoablation covering the entire lesion volume. Characteristics of patients eligible for cryoablation were comparing with not selected patients. Results: Mean tumour size was 64 mm (10-178). Most frequent histological subtypes were unclassified sarcomas (n=16), liposarcomas (n=15), or myxofibrosarcomas (n=7). Surgical treatment consisted in wide excision (n=16), or combined treatment (n=24). After surgery, the severe complications rate was 47.5%. Since relapse, mean follow-up was 42.8 months with a median overall survival of 57.6 months and median recurrence-free survival of 39.5 months. A subgroup of 13 patients was identified and comparison with other patients showed that trunk, shoulder and pelvic girdle locations (p =0.002), locally aggressive (P=0.016) and deep (P=0.002) tumours, ²5 cm (P=0.044), and liposarcoma and myxofibrosarcoma subtypes (P=0.007) were indicative of eligibility for cryoablation. Conclusion: Eligibility criteria as defined are useful for plan cryoablation as a technically feasible alternative to surgery for treatment of local relapse of STS. Robot-assisted radiofrequency ablation of liver tumours: early experience B.J.J. Abdullah, C.H. Yeong, K.L. Goh, B.K. Yoong, G.F. Ho, C. Yim; Kuala Lumpur/MY (basrij@ummc.edu.my) We report our preliminary experience of RFA of the liver tumours using a robotic-assisted guidance system. Methods and Materials: 6 patients with 8 lesions were treated using the Robio Ex (Perfint Healthcare, MA, USA) robotic positioning system. All the lesions were smaller than 2.5 cm diameter. All the procedures were performed under general anaesthesia. Following baseline CT scans, the lesions were identified. The puncture site and trajectory were then determined on Robio Ex workstation. The angulation of the needle, depth of lesion, the fluoroscopic dose as well as the accuracy of placements was determined. The performance level of procedures was documented for each biopsy on a five-point scale (5-1: Excellent-Poor). Results: All the tumours were targeted successfully. One lesion in 2 patients required minor readjustment. 4 patients (5 lesions) had needle placement with no cranio-caudal angulation, whereas 2 patients (3 lesions) had cranio-caudal angulation of up to 200. The orbital angulation ranged from 60 to 1180. The depth of needle ranged from 12.2 to 4.7 cm from skin surface. Performance levels were all 5 except in one patient (4). The fluoroscopic (DLP) and total dose (CTDIvol) for the entire procedure were 316±92 mGy.cm and 260.83±70.02 mGy, respectively. Post-RFA CT scans showed successful ablation of the targeted lesions. No immediate complications were noted. Conclusion: Robotic-assisted planning and needle placement appear to be technically easier, it requires fewer number of needle passes, fewer check scans Using logistic regression, CCS more than 100 was the predictor of presence of OMS (odds ratio 7.484, 2.459-22.776 in 95% confidence interval). The prevalence of OMS was significantly higher in patients with more than 50% stenosis and in patients with mixed and non-calcified plaques. The prevalence of OMS on DE-MRI and significant coronary disease on CTCA are not uncommon even in asymptomatic patients with type 2 diabetes. CCS more than 100 is the only predictor of OMS. Author Epicardial fat volume and coronary artery disease at CT: racial differences in African American and white patients with acute chest pain P. Apfaltrer 1 , A. Schindler 2 , U.J. Schoepf 2 , J. Nance 2 , U. Ebersberger 2 , R. Vliegenthart 2 ; 1 Mannheim/DE, 2 Charleston, SC/US (paul.apfaltrer@umm.de) Purpose: Thoracic adipose tissue likely promotes coronary artery disease (CAD). Possibly, differences in CAD risk between races are influenced by racial differences in thoracic adipose tissue. We compared CT-derived measures of thoracic fat and potential correlations with CAD between African American and white patients. Methods and Materials: 372 age-and-gender-matched black and white patients (186 black: mean age 54±11 yrs, 50% men; 186 white: mean age 54±11 yrs, 50% men) who underwent thoracic dual-source CT for chest pain evaluation were retrospectively included. Epicardial adipose tissue (EAT) volume and mediastinal adipose tissue (MAT) volume were quantified using an automated analysis algorithm. Peri-coronary fat thickness (PFT) was measured on reconstructed sections orthogonal to the right coronary artery centreline. Non-calcified and calcified plaque volume was quantified by applying a threshold-based automated algorithm. CAD was defined as 50% or greater coronary artery stenosis. Patients with CAD showed significantly higher EAT than those without CAD (97.9±52.6 cm 3 vs. 77.4±43.5 cm 3 , p < 0.05). Significant correlations were observed between EAT measurements and calcium volume (r=0.221; p < 0.05). The relationship between race and extent of adipose tissue remained significant after adjustment for cardiovascular risk factors. Conclusion: Measures of thoracic fat were generally higher for symptomatic white than for black patients suggesting a differential relationship between thoracic adipose tissue and CAD pathophysiology by race. Purpose: The Imactis Navigation System with electromagnetic needle holder tracking was developed to allow interactive display of the needle trajectory in a 3D volumetric CT volume, allowing the radiologist to choose optimal entry point and track to the target during CT-guided percutaneous interventions. The CTNAV trial compares the accuracy of the needle placement using standard CT procedure (CT group) and using the navigation system procedure (NAV group). Methods and Materials: Prospective, randomised, comparative, open, controlled study conducted between June 2010 and January 2012 in Grenoble University Hospital on 120 patients who had to undergo a percutaneous CT procedure. Patients were randomised to have normal procedure (CT group) or Navigation System assisted procedure (NAV group). The main outcome was the distance between the planned trajectory and the effective needle trajectory after the first placement attempt. Significance was set at 0. Friday dynamic contrast-enhanced MRI (DCE-MRI) and histology, we assessed the impact of this therapeutic approach on the tumour vasculature. Methods and Materials: Rats bearing breast cancer bone metastases were imaged using VCT and DCE-MRI prior to and 25 days after the onset of therapy; untreated (n=12) and treated (integrin inhibitor monotherapy; n=12) or together with antiresorptive agent (combination therapy; n=11) to assess osteolysis and functional MRI parameters, respectively. Mean vessel diameter and SMA and collagen-IV-positive vessel area fraction were assessed histologically. Results: Compared to the control group, bone defect healing at the osteolytic site occurred in rats receiving monotherapy and even more frequent after combination therapy as shown by VCT. In addition, we observed a profound effect of mono-and combination therapy on the tumour vasculature determined by DCE-MRI parameters amplitude and exchange rate constant. Both therapy regimens induced elevated vessel permeability/perfusion in bone metastases, but opposite to monotherapy, combination of agents additionally elevated the blood volume. Immunofluorescence analysis of osteolytic lesions revealed more tumour blood vessels after combination therapy and equally immature vasculature as compared to monotherapy. Conclusion: Upon treatment with integrin inhibitor monotherapy or in combination with an antiresorptive agent, vessel remodelling could be assessed by DCE-MRI. Interestingly, the degree of vessel remodelling could be correlated with bone defect healing, so we conclude the existence of a strong interaction between tumour angiogenesis and bone turnover in lytic osseous lesions. Purpose: Islet transplantation is a less invasive/safer/repeatable option than surgical pancreas transplantation for type 1 diabetic patients; it can be performed after kidney transplantation (IAK), alone (ITA) in patients without chronic renal insufficiency, or as an autotransplantation (IAT) after pancreatectomy (immunosuppression unnecessary). Steatosis is a consequence of islet engraftment: its meaning is controversial. Our longitudinal study aimed to assess steatosis incidence at ultrasound after islet auto-and allo-transplantation, and to identify any relationship with graft function. Ultrasound was performed at baseline/6/12/24 months in 108 islet-transplanted patients (33 IAK/50 ITA/25 IAT). Steatosis first detection/ prevalence/duration/distribution were recorded. Steatosic (S) and non-steatosic patients (NS) were compared for the following parameters at baseline/6/12/24 months: insulin independence rate, ß-score, C-peptide, glycated-haemoglobin, exogenous insulin requirement, fasting plasma glucose, infused islet mass. Results: Steatosis was found in 21/108 patients, 24% (20/83) allo-transplanted, 4% (1/25) auto-transplanted (better outcome), with first detection at 6 months, highest prevalence at 1 year (18 cases). S-patients had a significantly higher infused islet mass (IE/kg: S=10.822; NS=6.138) and worse basal metabolic conditions (ß-score: S=1.7±1.6; NS=2.8±2.8), but better islet function at the time of steatosis first detection (ß-score: S=3.9±2.0; NS=2.9±2.3), after which a progressive islet exhaustion, along with steatosis disappearance, was observed. Conversely, in NS patients these parameters remained more stable in time. Conclusion: Steatosis at ultrasound is significantly less detectable in auto-transplanted-patients with better clinical outcome. It seems to be related to stressed islets' overworking activity (higher ß-score values when steatosis appears), and a higher infused islet mass. Steatosis presence precedes metabolic alterations and (Structural Insight) was adapted in order to allow calibrated bone density and bone structure analyses of the vertebral bodies, using an underlying light weight calibration phantom with design for coronary calcium scoring (Image Analysis Phantom® Purpose: To validate a magnitude-based method, transposable on any imaging system and for all current clinical fields (1.5 and 3.0 T) for liver fat volume fraction (FVF) quantification without dominant component ambiguity problems. Methods and Materials: MR imaging was performed at 1.5 and 3.0 T using a multiple-angle multiple-gradient echo acquisition. A quantification algorithm correcting for relaxation time effects using a disjointed estimation of T1 and T2 * of fat and water and accounting for the NMR spectrum of fat was developed. Validations were performed in a prospective comparative study with histology on 28 patients with chronic liver diseases. Results: MR-estimated FVF and histological results were strongly correlated (ρ=0.96). ROC analysis showed that FVF allowed the diagnosis of a mild (cut-off = 5.5%) and a moderate steatosis (cut-off=15.2%) with a sensitivity/specificity of 100%. Water relaxation times (T1 and T2*) were found significantly reduced in patients with iron deposition (p < 0.01), whereas water T1 was found significantly increased in patients with cirrhosis (p < 0.01). Conclusion: This method that can be performed at 1.5 and 3.0 T on all imaging systems provide an accurate quantification of the FVF in patients with chronic liver disease. FVF could be a relevant biomarker for the clinical follow-up of patients with NAFLD as well as to quantify steatosis in the full spectrum of chronic liver diseases. Interestingly, thanks to the separated estimation of fat and water relaxation times, detection of cofactors such as iron deposition or cirrhosis in patients with NAFLD could be achieved. Combination of liver intravoxel incoherent motion imaging with MR fat quantification at 3.0 T to distinguish between pure steatosis and NASH Purpose: To evaluate the combination of liver intra-voxel incoherent motion imaging (IVIM) and a MRI fat quantification method at 3.0 T to make the distinction between NASH and pure steatosis. A multi-angle multi-gradient echo acquisition combined with a dedicated algorithm was used to quantify liver fat volume fraction (FVF), corrected for water and fat relaxation times and accounting for the NMR spectrum of fat. IVIM was performed using a single-shot SE-EPI sequence, in free breathing, with 11 b-values (0-20-40-60-80-100-200-300-400-600-800s.mm -2 ) and a weighted signal averaging procedure. Three orthogonal diffusion gradients were sequentially applied. A 2000 ms TR, 54 ms minimum TE; 21 axial slices of 8 mm thick; 400×300 mm² FOV; 128×96 matrix were used. IVIM parameters (pure molecular diffusion coefficient (DSlow), perfusion-related diffusion coefficient (DFast) and perfusion fraction (f)) were estimated. MR imaging was performed on a healthy volunteers group (n=33), and on patients with histologically confirmed pure steatosis (n=16) or NASH (n=4). Results: Wilcoxon test showed that DSlow was significantly lower when fat is present (FVF > 5.5%) (p < 0.01). DSlow and DFast were found significantly reduced between subjects with pure steatosis (Brunt=0) and NASH (Brunt> 0) (p < 0.05). Conclusion: Fat vesicles in pure steatosis restrict molecular diffusion without modification of micro-perfusion. In NASH, fibrosis still increase the restriction of molecular diffusion compared to patients with pure steatosis and decrease the microperfusion as illustrated by the decrease of perfusion-related diffusion coefficient. These preliminary results suggest that combining MRI fat quantification and IVIM could be a none invasive mean to distinguish between pure steatosis and NASH. Quantification of steatosis hepatitis and liver iron overload in a population-based study using magnetic resonance imaging J.P. Kühn 1 , D. Purpose: To describe hepatic biochemistry in biopsy-proven NAFLD states using 31 P-MRS and to evaluate its diagnostic performance for distinguishing non-alcoholic steatohepatitis (NASH). Methods and Materials: The cohort consisted of healthy controls (n=19), and 132 NAFLD patients with liver biopsy, as follows: simple steatosis (SS, n=37), NASH with non-significant fibrosis (NASH-NSF, n=49) and NASH with significant fibrosis (NASH-SF, n=46). 31 P-MRS was performed on a 3 T MRI to obtain signal intensities for phosphomonoesters (PME), phosphodiesters (PDE) and component glycerophosphocholine (GPC), total adenosine triphosphate (ATP) and component α-ATP, and inorganic phosphate (Pi). These were expressed as percentages relative to total phosphate and compared using one-way ANOVA with post hoc Bonferroni test. Receiver operating curve (ROC) analysis was performed to determine cut-off values with highest Youden index. Statistical significance was declared at α< 0.05. Results: Compared with controls, all NAFLD groups had higher PDE (p < 0.049). SS and NASH-NSF had decreased PME (p=0.001-0.015), increased GPC (p < 0.001), normal total ATP (p=0.067-1.000) and decreased Pi (p=0.018-0.021). NASH-SF had normal PME (p=0.764) normal GPC (p=0.727), decreased total ATP (p=0.035) and normal Pi (p=0.443). α-ATP was significantly decreased in both NASH groups and identified as a potential diagnostic marker. The computed area under the ROC was 0.705, and an α-ATP threshold of < 13.13% gave a 65% sensitivity and 73% specificity for the identification of NASH. Conclusion: 31 P-MRS shows observable spectroscopic patterns within the NAFLD spectrum. α-ATP is a potential diagnostic marker for distinguishing NASH from SS. Clinical implications of fatty liver on hepatic diffusion-weighted imaging studied in healthy subjects H. Dijkstra, A. Handayani, P. Kappert, M. Oudkerk, P.E. Sijens; Groningen/NL (h.dijkstra01@umcg.nl) Purpose: To evaluate the diagnostic implications of fatty liver on DWI by assessing the hepatic fat fraction (HFF) and T2* of healthy subjects in eight liver segments in order to eliminate patient-related confounding factors such as cirrhosis and fibrosis. Methods and Materials: Eleven healthy volunteers were examined with DWI (seven b-values) and two series of in-and out-of-phase dual-echo spoiled gradient echo sequences (SPGR) to obtain the HFF (Dixon's method). A third SPGR series was acquired to calculate T2 * relaxation. DWI data were analyzed using the IVIM model: molecular diffusion (Dslow), microperfusion (Dfast) and the respective fractions (fslow/fast). For each subject, four circular regions-of-interest (ø22.3 mm) were drawn in each segment according to the Couinaud-Bismuth classification. Data with low SNR< 5 were excluded. IVIM parameters were compared between groups of low (²2.5%), intermediate (2.5²HHF< 10%) and high HHF (> 10%). Linear correlations between HHF, DWI parameters, and T2 * were assessed. Results: In each segment, Dslow decreased with increasing HFF. Dslow averaged over all segments differed significantly (p < 0.001) between low (0.99×10 -3 mm 2 /s), intermediate (0.74×10 -3 mm 2 /s) and high HFF (0.32×10 -3 mm 2 /s). Both Dslow and T2* decreased with HFF (R 2 =0.89; R 2 =0.72). Dfast and fslow/fast showed small intergroup differences (p < 0.04). Conclusion: Increasing hepatic fat fractions caused significant reduction of the molecular diffusion and shortening of T2*. This implies that hepatic DWI hindered by fat leads to apparent fluctuations of the molecular diffusion and hypointensity on DWI images; this may induce false diagnoses such as fibrosis or cirrhosis. (p < 0.001/p < 0.001), whereas there was no significant correlation between BAT volume and the amount of subcutaneous adipose tissue (p=0.70). BAT activity was an independent, negatively influencing variable for liver fat content (p=0.027). Conclusion: BAT significantly correlates with body fat composition, especially visceral fat mass considered relevant for the development of metabolic syndrome, and seems to be an independent regulator of hepatic steatosis. In-phase/opposed-phase MRI and MR spectroscopic measurements for the quantification of liver fat content in morbidly obese patients H. Agreement for the three individual liver segments (II, IV and VII) had upper/lower limits of +5.0/-11.9%, +1.9/-9.6% and +4.8/ -12.0% and insignificant biases of 3.4% (p=0.14), -3.9% (p=0.25) and -3.6% (p= 0.27), respectively. Conclusion: IP/OP imaging and MRS are reliable methods for the assessment of LFC. IP/OP imaging is superior in terms of processing time and liver coverage and provides information for cases with larger regional fat differences and is helpful for lipid assessment in the left liver lobe where MRS is impractical. Purpose: Pancreatic islets transplantation (islets-tx) is a promising treatment for patients with type-1 diabetes. Neoangiogenesis of transplanted islets is a crucial phenomenon for engraftment and was investigated with DCE-MRI in mice. The aim was to use DCE-MRI in clinical islets-tx to evaluate the relationship between early vascular changes, islets loss and long-term clinical outcome. Methods and Materials: 6 diabetic pts were enrolled. DCE-MRI was performed at baseline and 7 days after islet-tx with a 3D-T1w-TFE dynamic sequence (temporal resolution: 4sec; 45 dynamics) acquired during gadolinium bolus injection. K-trans was assessed by DCE-MRI datasets. Three patients received Ferucarbotran labelled islets and were monitored with T2*sequences (before islets-tx, 7 days and each month after). Unlabelled islets were infused in the remaining three patients. Glycated haemoglobin, blood glucose, daily insulin request and stimulated C-peptide were monthly assessed in order to calculate beta-score (0-8) Purpose: Brown adipose tissue (BAT) mass and activity is considered a significant factor for the development of adiposity and metabolic syndrome in humans, and represents a natural target for the modulation of energy expenditure. We evaluated the correlation of BAT activity and active volume as detectable on FDG-PET/CT scans with abdominal body fat composition and liver fat estimation. Methods and Materials: 4852 FDG-PET/CT examinations in 3680 individual patients were screened for BAT, resulting in 601 patients and controls for subsequent analysis, matched for exam date and therefore ambient temperature, age, and gender. In addition to BAT volume and activity, an automated segmentation was used to determine visceral fat and subcutaneous fat as well as lean tissue in the abdomen. Liver fat was estimated in 430 patients with non-contrast-enhanced CT. Spearman rank correlation between parameters and a multi-variate model for liver fat excluding influencing parameters was calculated. Results: BAT volume and activity showed a significant inverse correlation with total adipose tissue (activity p < 0.001/volume p=0.022) and visceral adipose tissue In 15 studies, which were mainly underpowered and of heterogeneous study design, 31 different parameters were studied. Most frequently studied parameters were tumour diameter or volume, Ktrans, Kep, Ve, and apparent diffusion coefficient (ADC). Other parameters were analysed in only two or less studies. Tumour diameter, volume, and kinetic parameters did not show any pretreatment differences between responders and non-responders. In two studies, pretreatment differences in ADC were observed between study groups. At early response monitoring significant and non-significant changes for all parameters were observed for most of the imaging parameters. Conclusion: Evidence on distinguishing responders and non-responders to neoadjuvant chemotherapy using pretreatment MRI, as well as using MRI for early response monitoring, is weak and based on underpowered study results and heterogeneous study design. Thus, the value of breast MRI for response evaluation has not yet been established. S249 A C D E F G BFriday The role of magnetic resonance imaging in assessing residual disease and pathologic complete response in breast cancer patients receiving neoadjuvant chemotherapy: a systematic review R. Prevos 1 , M. Smidt 1 , V. Gadovist®) was injected intravenously at a dose of 0.1 mmol/kg BW and six dynamic T1w GRE sequences (VIBE) were collected. The contrast kinetics of all malignant lesions were analysed quantitatively on a pixel by pixel basis using a computer-aided detection system (iCAD). The signal enhancement pattern was coded by three colour intensities and three colour hues. Pharmacokinetic changes were analysed based on the Tofts model including vascular permeability and extracellular volume fraction. Results: In comparison to the baseline MRI, follow-up examinations showed a significant tumour size reduction of 57% on average. A decrease of colour hues and colour intensities demonstrated significant changes in contrast kinetics. Vascular permeability revealed a statistically significant decrease (p < 0.05). However, extracellular volume fraction changes revealed only a slight decrease under chemotherapy (mean decline of 16%). The CAD analysis provides a reliable evaluation of tumour size, contrast kinetics, vascular permeability and extracellular volume fraction within a reasonable time. This form of CAD analysis provides a fast and reliable assessment of early treatment response, enabling a fast modulation of therapy for non-responders. Purpose: To assess the use of RECIST, mRECIST and volumetric measurements in patients with Invasive ductal carcinoma (IDC) with initially marked necrosis on neoadjuvant chemotherapy (NACT). In prospective analysis of 71 patients, 14 patients were selected based on marked intralesional necrosis and examined 3 times on MRI: before the beginning, after the 2 nd cycle and upon completion of NACT (anthracycline/taxane-based regimen). The lesions were measured in axial plane according to RECIST and mRECIST. The volumes of the entire lesion and of the viable tissue were computed. Results: The longest diameters measured according to RECIST and mRECIST and the appropriate volumes were significantly different initially, after the 2 nd cycle and upon the completion of NACT (p < 0.001 for all). The size of the lesions was significantly different with/without the necrotic areas. Differences in tumour diameter and volume change (delta; %) between RECIST and mRECIST were not significant after the 2 nd cycle and upon completion of NACT (p> 0.01 for both). According to either RECIST or mRECIST, including the volume measurements, the same number of patients were classified in the same response category, i.e., early response -PR (21.4%); late response -PR (50.0%). Conclusion: To our knowledge, this is the first trial testing the use of mRECIST in extrahepatic setting. There was no significant difference in changes of diameters or the corresponding volumes according to RECIST Vs. mRECIST. Further research in larger groups needs to assess the use of the tools in the follow-up of new NACT protocols. Purpose: To assess the potential value of fibrosis quantification using T1 mapping in hypertrophic cardiomyopathy (HCM) in comparison to late contrast enhancement imaging, circumferential strain and LV thickness. Methods and Materials: Seventeen patients with HCM, and 11 controls subjects were prospectively included. All patients underwent cardiac MR with the following sequences: 1) cine sequence, 2) tagging sequence CSPAMM TR/TE=37.1 ms/1.4 ms; matrix 256, FOV 340, temporal resolution 37.1 ms, distance between tag: 6 mm, short axis. 3) Molli sequence (TR/TE=3.0 ms/1.5 ms; matrix 144-150, thickness:7 mm) acquired before and 5, 7, 9 min after gadolinium injection (DOTAREM, 0.2 mmol/kg). 4) Late gadolinium enhanced sequence 10 min after injection. T1 values were assessed in blood and in the 6 segments of the mid-LV slice. Statistical analysis were performed for patients and for segments with (+) and without (-) enhancement on LGE. R1, ΔR1, ΔR1 ratio were calculated (partition coefficient of Gd, λ). Results: In HCM, λ was significantly different between patient with (0.54±0.08) and without (0.45±0.05) enhancement on LGE (p < 0.0001). No significant difference was measured in λ value between control and HCM without delayed enhancement (p=0.1). We did not found any correlation between lambda and circumferential strain (r=0.11; CI (-0.12;0.34); p=0.3). On the other hand, we found a significant correlation between LV wall thickness and circumferential strain (0.40; CI (0.20;0.56); p < 0.0001). In HCM, fibrosis is a focal process. In our study, there were no correlation between the presence of fibrosis and circumferential strain, but we found a significant correlation between LV wall thickness and circumferential strain. Purpose: There is no consensus on surveillance strategies of reconstructed breasts after breast cancer, and it is routinely based on clinical examination alone. This study aims to assess the incidence and radiological presentation of breast cancer recurrences after deep inferior epigastric perforator (DIEP) flap reconstruction for women with a history of breast cancer. Methods and Materials: 265 consecutive women who underwent DIEP flap reconstruction after breast cancer from 1997 to 2009 were included in this retrospective study. All had annual screening for recurrence and we reviewed their follow-up records in our institution. The date and site of recurrences -ipsilateral or controlateral to the reconstructed breast, regional and metastatic disease -were retrieved. Clinical and radiological presentations -on mammography, ultrasound, and MRI -were further analysed. Results: 31 of 265 patients presented 34 relapses, with a mean delay of 4.7 years (SD=2.9) after DIEP reconstruction; 14 (41%) were ipsilateral, while 6 (18%) were controlateral and 14 (41%) metastatic. Ipsilateral recurrences had a tendency to occur earlier (3.8 years, SD=2.4, p=0.11) and 12 presented at a clinically patent stage. Purpose: To assess the potential value of segmental quantification of myocardial fibrosis using T1 mapping in dilated cardiomyopathy (DCM) in comparison to late contrast enhancement imaging and circumferential strain. Methods and Materials: Seventeen patients with DCM, and 11 controls subjects were prospectively included. All patients underwent cardiac MR with the following sequences (parameters set according to recommendation of the SCMR): 1) cine sequence, 2) tagging sequence CSPAMM TR/TE=37.1 ms/1.4 ms; matrix 256, FOV 340, temporal resolution 37.1 ms, distance between tag: 6 mm, short axis. 3) Molli sequence (TR/TE=3.0 ms/1.5 ms; matrix 144-150, thickness: 7 mm) acquired before and 5, 7, 9 min after gadolinium injection (DOTAREM, 0.2 mmol/kg). 4) Late gadolinium enhanced sequence 10 min after injection. T1 values were assessed in blood and in the 6 segments of the mid-LV slice. Statistical analysis were performed for patients and for segments with (+) and without (-) enhancement on LGE. R1, ΔR1, ΔR1 ratio were calculated (partition coefficient of Gd, λ). Results: In DCM, λ was not significantly different between patient without (0.50±0.05) and with at least one segment showing enhancement on LGE (0.52±0.06; p=0.06). In all DCM, λ was significantly higher compared with the value obtained in control subject (p < 0.0001). We found a significant correlation λ and circumferential strain in each segment (r=0.55; CI (0.39;0.68); p < 0.0001), and between λ and LVEF (r= -0.56; CI (-0.82;-0.11); p < 0.01). Conclusion: In DCM, fibrosis was a diffuse process involving all the myocardium. There was a correlation between the quantity of fibrosis, circumferential strain and LVEF. .051). The correlation between US and CMR end-dyastolic and stroke volume indexes was significant but with a very low coefficient, while the correlation for the ejection fraction was acceptable. The ICC was unsatisfactory for all volumes and good for the ejection fraction. The widest Bland Altman plot range was found for the end-diastolic volume index. In conclusion, metrics of LV volume index and function showed significant systematic inter-modality differences. In particular, the US volumes were systematically underestimated. This suggests that serial measurements of volumes and function in TI should be performed using the same method and, if available, the more reproducible CMR technique. Author Disclosures: C. Tudisca: Research/Grant Support; The MIOT project receives "no-profit support" from industrial sponsorships (Chiesi Farmaceutici S.p.A., ApoPharma Inc. and Bayer-Shering). This study was also supported by: "Ministero della Salute". . obtained 15 min after injection of 0.2 mmol/kg of Gadolinium. LGE was quantified automatically and defined as area of myocardium with signal intensity 6SD above the mean signal of remote myocardium. Indexed end-diastolic left ventricular mass (IEDLV mass) was assessed and LGE extension was defined as percentage of total IEDLV myocardium mass. Patients were followed prospectively for a mean of 40.2±11.1 months, during which period occurrence of VT and ICDs were recorded. Purpose: Noncompaction of the left ventricle myocardium (LVNC) is a rare cardiomyopathy characterised by multiple and excessive trabeculations, deep intertrabecular recesses and thickened ventricular myocardium. This condition is considered mostly congenital but acquired forms have also been described. Aim of the present study is to assess LVNC prevalence in β-thalassaemia patients and its potential association with cardiac siderosis Methods and Materials: 229 transfusion-dependent patients with β-thalassaemia (160 major and 69 intermedia, mean age 37.8 ± 12.8 years, mean BSA 1.64 ± 0.24 Kg/m 2 ) presenting for cardiac and abdominal iron assessment by MRI (1.5T Scanner, Avanto, Siemens-Germany) were studied. Cardiac iron overload was assessed by T2* Black-Blood gradient-multiecho sequences; cardiac functional and morphological characteristics were evaluated using SSFP acquisitions. Risk factors for LVNC were noted and none of the patients had neuromuscular or congenital heart disease. Results: 69 patients (30%) fulfilled the preassigned strict criteria for LVNC on cardiac MRI. There were no statistically significant differences between patients with and without LVNC with respect to demographics, haemoglobin levels, splenectomy status, systemic, hepatic, and cardiac iron overload indices, iron chelation therapy. Patients with LVNC showed a significant lower cardiac functional performance (Ejection Fraction; volumes impairment). Conclusion: Patients with β-thalassaemia have a higher prevalence of LVNC than normal individuals suggesting an underlying iron deposition mechanism to explain this condition in absence of conventional risk factors. These data seem to be crucial regarding an entity with adverse cardiac outcomes, especially in patients with β-thalassaemia where cardiac disease remains a primary cause of mortality. ranged from 2.3 mm to 34.3 mm (mean = 11.3 mm). Involvement of internal carotid artery (n = 9, 64%) was more common than external carotid artery (n = 5, 36%). Petrous segment of ICA was the most commonly involved segment (n = 5, 36%), followed by cervical segment of ICA (n = 4, 29%) and maxillary artery (n = 3, 21%). Conclusion: Carotid blowout syndrome following RT were more common in our study subjects with advanced T and N stage of NPC, local recurrence and repeated RTs. Pseudoaneurysms were identified in most patients. ICA involvement was more common and petrous segment of ICA was the most commonly involved segment. Of the 6 patients with involvement of PNS, one presented with orbital extension. Nasopharyngeal and oropharyngeal involvement was seen in two cases. In 20 cases (77%), the primary tumours seen as diffuse enhancing mucosal thickening. In five cases (19%), the primary tumours seen as an enhancing mass lesion. In one case (4%), the primary tumour was undetectable. Bone destruction was noted only in 3 cases (12%). Conclusion: Nasal-type NK/T-cell lymphomas of the sinonasal regions often presents with diffuse mucosal thickening rather than mass lesion. And they can mimic inflammatory disease such as sinusitis. Radiologists should be familiar with these findings indicative of the possibility of NKTL, and should perform a histopathologic confirmation to establish a diagnosis. Results: A significant relationship between symptoms and morphological manifestations was found (disk displacement (p < 0.001), osteoarthritis (p < 0.001) and effusion (p = 0.001)). In the group without reduction there were significant increases in the risk of experiencing symptoms (p = 0.002) in the group with reduction the risk was marginal (p = 0.071). Significant correlation between age and osteoarthritis (p = 0.001) and age and effusion (p = 0.022) was found. There was no correlation between sex and morphological manifestations. Significant increases in the risk of experiencing symptoms were found in the group with morphological manifestations (disk displacement (p = 0.006), osteoarthritis (p < 0.001) and effusion (p < 0.001)). Statistically marginal results were verified with multivariate analysis. Conclusion: MRI morphological manifestations of the TMJ correlate with the presence of symptoms, therefore MRI has a crucial role in the diagnosis of treatment of TMJ dysfunction. Purpose: To compare image quality of FBP, ASIR and VEO reconstructed CT images of the neck in tumour patients with a contrast-enhanced scan. Methods and Materials: Consecutive regular contrast-enhanced tumour staging CT-scans (Discovery HD750, GE; helical, 0.8s, 120 kV, 50-400 mA mod., NI 33) of the neck were reconstructed using FBP, ASIR and VEO; n=27. Image quality at three defined heights (lymph node levels=LNL 2, 3, 7) were independently rated by 2 radiologists blinded to the reconstruction algorithm. Readers rated image quality including artefacts, contrast and noise using a semi-quantitative scale of 0 to 10 (lower than 5 was defined as non-diagnostic) yielding a summary score for each height. Wilcoxon´s test was used for statistical testing. ICC was calculated. Purpose: Maxillary sinus pyocele is a true chronic abscess found in drugrefractory sinusitis. The purpose of this study is to define this new entity and its MRI-characteristics. We retrospectively reviewed MRI datasets for 23 patients with "pseudotumoral sinusitis" on CT (including 2 bilateral cases). The MRI datasets were scored by two radiologists for morphological features, T1 and T2-weighted signal intensities, contrast enhancement and the degree of impact on the sinus mucosa and the retromaxillary fat. These features were compared with per-operative findings. Results: We observed a content presenting T1 low signal (92%), heterogeneous T2 low signal (92%), a capsule with contrast enhancement (100%) containing microabscesses (52%), a mass effect on the lateral nasal wall (100%) and retromaxillary fat stranding (88%). Eighteen pyoceles were treated endoscopically, with confirmation of a maxillary sinus abscess in all cases. Furthermore, we suggest a staging system for maxillary sinus pyocele. Conclusion: Maxillary sinus pyocele presents specific MRI characteristics. This entity must be suspected on sinus CT scan and recognised on MRI. Surgical endoscopic sinus surgery is needed. These findings therefore merit further investigation. Purpose: To compare MR imaging at 1.5-and 3.0-T in the same individuals for performance in the diagnosis of cartilage lesions of the knee. This prospective study was approved by our Institutional Review Board, and informed consent was obtained from all patients. From December 2010 to February 2012, MR examinations of the knee at both 1.5-and 3.0-T were performed in 100 symptomatic patients (71 men, mean age 45y, range 17-75y) who underwent subsequent knee arthroscopy. Three blinded independent readers graded all articular surfaces seen at MR using the Noyes classification system. With arthroscopy as the reference standard, the sensitivity and specificity of the 1.5-and 3.0-T MR protocols for detecting cartilage lesions were calculated. Differences between the 1.5-and 3.0-T exams were compared using bootstrapping statistics (p < 0.05). Results: For all readers and grades of cartilage lesions combined, the respective sensitivity, specificity, and accuracy of MR for detecting cartilage lesions (n=144) were 60%, 96%, and 87%, respectively, at 1.5-T and 69%, 96%, and 90%, respectively, at 3.0-T. For detecting and correct grading of cartilage lesions, the readers performed significantly better with 3.0-T than with 1.5-T (p=0.001). Conclusion: A comprehensive MR protocol at 3.0-T significantly improves diagnostic performance for evaluating the articular cartilage of the knee in symptomatic patients, when compared with a similar protocol performed at 1.5-T. Purpose: The purpose of this study is evaluation of correlation between relative signal intensity of MR images in retrodiscal tissue, superior and inferior heads of pterygoid muscle in TMD patients with types of anterior disc displacement and condylar flattening. In this cross-sectional study, 31 MR images of patients who had anterior disc displacement were evaluated. After relative signal intensity measurement for retrodiscal tissue, superior and inferior head of lateral pterygoid muscle, the correlation between relative signal intensity and types of anterior disc displacement and also condylar flattening was evaluated. Results: The correlation between relative signal intensity of MR images and type of anterior disc displacement in retrodiscal tissue (p-value=0.10), superior head of lateral pterygoid muscle (p-value=0.68) and inferior head of lateral pterygoid muscle (p-value=0.40) was not significant. There was also no statistically significant correlation between relative signal intensity of MR images and flattening of condylar head in retrodiscal tissue (p-value=0.75), superior head of lateral pterygoid muscle (p-value=0.49) and inferior head of lateral pterygoid muscle (p-value=0.60). We found that although MRI is a non-invasive procedure in the diagnosis of TMD, probably relative signal intensity of MR images in retrodiscal tissue, superior and inferior head of pterygoid muscle is not a good predictor for type of anterior disc displacement and flattening of condylar head. It seems that this cannot be used as a diagnostic marker for TMD progression. High resolution 3D MR imaging of the temporomandibular joint: feasibility and comparison with 2D sequences U. Navarro, M. Ravanelli, D. Farina, E. Botturi, R. Maroldi; Brescia/IT (navarrougo@gmail.com) Purpose: To assess the feasibility of high-resolution 3D MR imaging of the temporomandibular joint (TMJ) and to compare 3D and standard 2D techniques. Methods and Materials: Ten volunteers underwent a TMJ MR study with surface coils including a proton density (PD) fat-saturated 3D sequence "SPACE" and 2D PD fat-saturated sequences acquired on parasagittal and paracoronal planes. Twenty TMJ were imaged and analysed. The contrast between articular disk (AD) and bilaminar zone signals was measured on parasagittal images and normalised by the AD signal. Capability of 3D sequences to depict eight small anatomical structures of the TMJ (4 on parasagittal and 4 on paracoronal plane) was assessed and compared to that of standard 2D sequences. Results: Contrast between bilaminar zone and AD in 3D and 2D sequences was 2.93 and 2.61, respectively (p 0.34). Fifty-eight out of 80 structures assessed in parasagittal plane were detectable on 2D sequences, 67/80 on 3D sequences (p 0.03). Among the 80 structures assessed on paracoronal images, 40 were recognised on 2D sequences, 67 on 3D sequences (p 0.0001). Conclusion: High resolution 3D MR imaging of TMJ is feasible with 3D PD fatsaturated SPACE sequences. The detectability of anatomical structures, potentially key for joint functionality (ligaments) is enhanced in comparison to standard 2D sequences, especially on paracoronal plane. Results: AEA was identifiable in 106/106 on the axial plane, 106/106 on coronal and 105/106 on sagittal. In 43% of patients, the AEA canal run inside the skull base (condition #1), in 57% of cases a pneumatised cell was interposed between the canal and the skull base (condition#2), 52% of the pneumatised cells above the AEA canal were supraorbital cells, 35% supra-bullar recesses and 13% frontal sinuses. In these cases, the average distance between the AEA canal and the skull base was 2.2 mm (range 1. In 20 patients with KL grade 1-2 knee OA, dGEMRIC was acquired at 3 T using a 3D-SPGR sequence before and 3 months after HA treatment. To evaluate patient symptoms, the knee injury and osteoarthritis outcome score (KOOS) questionnaire was recorded at baseline and follow-up. We analysed 8 matching anatomical ROIs in the medial and lateral knee compartment in both examinations, using the T1 relaxation times as a measure of cartilage quality. Outcomes of dGEMRIC and KOOS at baseline and follow-up were compared using paired testing to evaluate the symptomatic and potential structural effects of HA. Results: Outcomes of dGEMRIC at follow-up (pooled median T1 504 ms) did not improve significantly compared to baseline (pooled median T1 490 ms) in any of the analysed anatomical cartilage ROIs. Patient complaints improved significantly in KOOS subscales: pain, daily-, and sports activities. Conclusion: Using dGEMRIC, no improvement in articular cartilage quality can be detected 3 months after HA. However, patient complaints decreased significantly after HA. Therefore, the results of this study suggest that the working mechanism of HA is not acting through an improvement of sGAG content in the cartilage. Purpose: To analyse the spatial resolution of different reconstruction kernels and acquisition protocols including a prototypic high-resolution protocol in flat-panel (FP) and multi-detector (MD) CT to evaluate contrast and cartilage depiction quality of FPCT and MDCT arthrography. A cone-beam image quality phantom was used to compare resolution and different reconstruction kernels of standard MDCT (120 and 80 kV), standard binned (2x2) and prototype high-resolution unbinned (1x1) FPCT protocols (5s and 20s runs each). With the resulting FPCT kernel best matching the standard MDCT kernel (U90u), joint phantoms with differently sized cartilage defects were scanned. CT numbers and noise in iodine contrast and phantom cartilage tissue were measured, and contrast-to-noise ratios (CNR) were calculated. Depiction quality of cartilage defects was qualitatively rated by two independent radiologists. Results: A sharp reconstruction kernel for all FPCT protocols best matched the resolution of the standard MDCT kernel. High-resolution 20s 1x1 binning FPCT showed superior resolution in higher frequencies than 1.6 lp/mm. The CNR were highest in 20s FPCT, followed by 5s FPCT binned and MDCT protocols. Interreader agreement for depiction quality of cartilage defects was substantial and high in joint phantoms (0.74 and 0.8, respectively; p < 0.001). The best ratings of cartilage defect depiction quality were seen in FPCT 20s, followed by FPCT 5s and MDCT acquisitions. Conclusion: FPCT arthrography offers superior CNR and cartilage defect depiction quality to MDCT, and spatial resolution for small structures is higher when applying high-resolution acquisition protocols. subjects with risk factors for OA (incidence cohort) and 40 subjects from the control cohort. Right knee 3 T MRIs were analysed at baseline and 48 months. Coronal FLASH sequence was used to measure cartilage volume at baseline, multi-echo spinecho sequence to generate T2 maps at baseline and 48 months. Regression models were adjusted for age, gender and BMI and were applied to 4 compartments (medial femur, lateral femur, medial tibia and lateral tibia). Results: Global T2 measurements increased in all cohorts over 48 months. Baseline T2 were significantly greater in the progression cohort compared to incidence and control cohort (P < 0.001), whereas 48-month follow-up data showed significantly greater measurements in the Incidence cohort (P < 0.003). Most pronounced T2 changes over time were observed in the incidence cohort (P < 0.023), changes in the progression cohort were not significant. Mean volume did not significantly differ between the cohorts, but progression cohort subjects showed the highest volumes in all compartments. Purpose: The goal of the study was to demonstrate the benefits of T2 mapping to the assessment of lumbar disc repair after the ADCT. Methods and Materials: 50 patients, male and female, age range 18-40, with a single-level degenerative disc disease (DDD) were studied. All patients had a standard lumbar microdiscetomy performed and 4-6 weeks after the surgery underwent the ADCT. Prior to the surgery, one month later and 3, 6 and 12 months after the ADCT each patient had a MR examination on the 1.5 T MR scanner. 20 patients completed a 12-month long follow-up protocol. T2 mapping revealed the level of DDD and the adjacent levels. The evaluation of signal intensity was carried out using pixel value software. Results: Each patient during the 12-month long follow-up reported a significant relief of pain: VAS score ranged 0-3, ODI score 0-20%. In the MR examination held after the ADCT, changes in signal intensity seen on T2-weighted MR images were reported. T2 mapping showed signs of the disc repair regardless of the lack of changes in disc dimensions. Mild increase of T2 with improved homogeneity of the structural morphology of the nucleus pulposus was observed on T2 after the ADCT. Conclusion: T2 mapping may be used for evaluating the changes of the molecular composition and structural integrity of the intervertebral disc after the ADCT and other novel restorative therapies. It has also the potential to be valuable in the detection of the early degeneration in the intervertebral disc. Purpose: To evaluate the feasibility of T2* and T1Gd mapping to assess glenohumeral cartilage, and to establish baseline values of healthy glenohumeral cartilage at 3 T. Methods and Materials: Forty asymptomatic volunteers (mean age: 24.8 ± 2.2 years) without shoulder abnormality were included. The MRI protocol comprised a three-dimensional (3D) double-echo steady-state (DESS) sequence for morphological cartilage evaluation, a 3D gradient-echo (GRE) multiecho sequence for T2* assessment, and a dual-flip-angle 3D GRE sequence for T1Gd mapping. Statistical assessment involved descriptive statistics establishing mean T2* and T1Gd values ± standard deviation and the one-way analysis of variance (ANOVA) to identify any significant differences between the T2* and T1Gd values of various regions of the glenohumeral joint. Intra-class correlation (ICC) analysis comparing repetitive T2* and T1Gd measures of ten randomly selected individuals was used to assess intra-and inter-observer reliability. Purpose: To evaluate the efficacy of the treatment of uterine adenomyosis using magnetic resonance imaging-guided focused ultrasounds (MRgFUS) with a new specific technical plan. Twenty-four patients aged between 28 and 47 years (mean age 37.5), with symptomatic adenomyosis and uterine fibroids were treated with MRgFUS in our department, from October 2011 to July 2012. This study evaluates the findings on 6 patients affected by adenomyosis alone. Symptomatology was assessed through the symptom severity score questionnaire. One single treatment was performed with an average energy delivered to each patient equal to 2840 J (with a minimum value of 1300 J and maximum of 4800 J). The longest treatment duration was 120 minutes. The plan employed was characterised by high density and reduced size of the spot length (ranging from 4 to 6 mm) with the shortest cooling time between the sonifications. Results: The evaluation of the non-perfused volume on the c.e. T1-weighed sequences performed 6 weeks after treatment, measuring each single slice, showed a maximum retraction of the necrotic area of 73% and a minimum of 52% with a mean value of 66.5%. After six weeks, the symptomatic score showed a reduction of about 80% if compared to the pre-treatment one. The treatment with MRgFUS allows a resolution of the symptoms and a reduction of the treated area, maintaining the integrity of the uterus, in a pathology which, up to now, has limited therapeutic perspectives. Is uterine artery embolisation in large sized myoma as efficient as in normal sized myoma: a retrospective comparative study in 263 patients H. Choi 1 , G. Jeon 1 , M. Kim 2 , J. Lee 1 , J. Yoon 1 , S. Hwang 1 ; 1 Seongnam/KR, 2 Seoul/KR (piscean84@hanmail.net) Purpose: The purpose of this study was to evaluate the effectiveness, safety and complications of uterine fibroid embolisation (UFE) when applied to myomas of large volume. A total of retrospectively collected 323 patients who underwent UFE for symptomatic uterine fibroids without adenomyosis between January 2005 and February 2011 were included in this study. Patients were divided into two groups: 63 patients were selected with large fibroid burden group, defined as a dominant fibroid with a longest axis ³10 cm or a uterine volume of ³700 cm 3 and remaining 260 patients with control group. Fibroid infarction and volume reduction with MRI, complications and patients' satisfaction score were evaluated. Results: The large fibroid group consisted of 63 (mean age 37.10 ± 5.62) women and 260 (mean age 37.33 ± 5.62) women included in control group. There were no statistical difference in average % volume reductions of dominant fibroid as 46% in large group and 41.19% in control group, the mean satisfaction score at immediate follow-up (average 2.94 months) and mid-term follow-up (average 32.63 months) and procedure related complications or major surgery following UFE. Conclusion: Uterine fibroid embolisation is a safe and effective treatment method which can be utilised in the treatment of myomas of large volume. The size of myoma is not a definite contraindication or poor prognosis factor for embolisation. : 76 leiomyomas in 60 women (average age 39.3 years) were treated with MRI-guided focused ultrasound (MRgFUS). The treatment is carried out using the ablative properties of the HIFU system under 3 T MRI guide. Symptoms were scored using Severity Score (SS) and quality of life was determined using the UFS-QOL score. Pre-treatment measurements of leiomyoma volume were obtained by MR images. After treatment, Non-perfused Volume (NPV) was calculated from T1-w contrast-enhanced MR sequences. The average volume of treated fibroids was 90.27 ± 90.4 mm3. Follow-up images were obtained 3, 6 and 12 months after treatment and served to determine leiomyoma shrinkage. Qualitative and quantitative relations between fibroid volume, NPV ratio at treatment, and 12-month shrinkage were measured. Results: MRgFUS treated patients demonstrated a significant change in USF-QoL score: mean SS score values were 48.6 ± 13.4 (pre-treatment), 25.1 ± 8.9 (threemonths follow-up), 22.1± 7.5 (six-months follow-up) and 19.3± 6.8 (twelve-months follow-up). Fibroids volume changed from 90.27±90.4 mm3 (before treatment) to 54 ± 66.1 mm3 (at 12 months follow-up). We encountered a statistically significant difference between the two values (p = 0.001). Mean post-treatment VNP was 57.65±52.9 mm3, about 63% of total fibroid volume (p=0.001). Conclusion: MRgFUS therapy of leyomioma results in a significant relief of symptoms and greater than 50% total fibroid ablation. The procedure is carried out in a totally non-invasive manner and features a high-safety profile. Results: MRI-guided focused ultrasound treatment was technically successful in 115 of 123 patients (93.5%). In 8 patients treatment was not possible due to bowel loops in the beam pathway that could not be mitigated (n=6), patient movement (n=1) and system malfunction (n=1). Average non-perfused volume ratio was 88±15% (range, 38 to 100). Mean applied energy level was 5400±1200J, and mean number of sonications was 74±27. No major complications occurred. Two cases of first degree skin burn resolved within one week after the intervention. Of the baseline characteristics analysed, only the planned treatment volume had a statistically significant impact on the non-perfused volume ratio. Purpose: Placenta percreta (PP) is a recognised cause of severe postpartum haemorrhage, with high risk of blood transfusions and emergency hysterectomy with maternal morbility and mortality. Our purpose is to evaluate the role of bilateral occlusion balloon catheter insertion in to both internal iliac arteries (IIA) before elective caesarean to prevent haemorrhage and to preserve the uterus. This is one of the longest cohort of women treated with prophylactic balloon occlusion and prevents caesarean hysterectomy in abnormal placentation. Methods and Materials: Twenty-two pregnant women who were identified as having a PP by US were treated prophylactically with bilateral occlusion balloon catheters placed in the anterior trunk of both IIA prior to elective caesarean. The balloons were inflated immediately after the baby delivery and deflated four hours later. Patients with peri-operative bleeding were treated with uterine artery embolisation (UAE), blood transfusion or hysterectomy. For each patient, estimated volume of blood lost and transfusion required was recorded. Results: Abnormal placentation was confirmed histologically as percreta (13), acreta (7) and increta (2). Estimated median blood lost during the delivery was noted 1.8L (range 0.5-12L). Postpartum haemorrhage occurred in nine patients, six had successful embolisation and three required hysterectomy. No foetal or mother death occurred. Conclusion: Prophylactic occlusion balloon catheter insertion in both IIA prior to elective caesarean deliveries in patients with abnormal placenta contributes to successful treatment, reduced blood lost and preserved the uterus in this high risk group of women. Results: A total of 11 transcatheter embolisation procedures of bilateral uterine arteries with or without extra-uterine feeding arteries were performed as the firstline treatment, and with a technical success rate of 82% (9/11). Embolisation was incomplete in two patients who had an extra-uterine blood supply or a dominant draining vein; the former recovered from menorrhagia during our close observation, while the latter underwent a successful second embolisation procedure. Clinical success was achieved in the remaining eight patients after a single procedure and there was no recurrence of bleeding. Only one minor complication occurred: rupture of the proximal UA. Recovery to their normal menstrual cycle was seen in all eight of the clinically successful patients, one of whom subsequently had an uneventful intrauterine pregnancy carried to term. .9 years ± 9.9 years) underwent a pre-therapeutic FDG-PET/CT scan and a FDG-PET/CT after the second cycle of NACT. Histopathology served as the reference standard. SUVmax of cancer lesions before and after the second cycle of NACT were measured. Two evaluation algorithms were used: (a) pCR: Sinn Score 3 and 4, npCR: Sinn Score 0-2; (b) pCR: Sinn Score 4, npCR: Sinn Score 0-3. The absolute and relative decline of the SUVmax (ΔSUVmax, ΔSUVmax (%))was calculated. Differences of the SUVmax and of the SUVmax decline between pCR and npCR lesions were tested for statistical significance (p <.05). To identify the optimal cut-off value of ΔSUVmax (%) to differentiate between pCR lesions and npCR lesions a receiver operating curve (ROC) analysis was performed. Results: Using evaluation algorithm A the ΔSUVmax was 13.5 (pCR group) and 3.9 (npCR group) (P = 0.006); the ΔSUVmax (%) was 79% and 47%, respectively (P = 0.001). On ROC analysis an optimal cut-off ΔSUVmax (%) of 66% was found. Using evaluation algorithm B the ΔSUVmax was 17.5 (pCR group) and 4.9 (npCR group) (P = 0.013); the ΔSUVmax (%) was 89% and 51%, respectively (P = 0.003). On ROC analysis an optimal cut-off ΔSUVmax (%) of 88% was found. Conclusion: FDG-PET/CT early differentiates between pCR and npCR after two cycles of NACT. In our study we prospectively enrolled 23 consecutive patients (M:F=20:3, mean age 70years) affected by HCC: 6 patients at presentation and 17 at restaging. In all cases we performed a whole body CHO-PET and compared findings with referring CT (n=20) and/or MRI scanning (n=11), for a total of 25 paired scans. The reference standard for validating imaging results was either histology (5 patients), or a multidisciplinary work-up. For every modality we determined diagnostic accuracy on a scan-based and on a site-based analysis. Results: On a scan-based analysis CHO-PET and CT/MRI demonstrated an accuracy of 86.4% and 88%, respectively, whereas on a site-based analysis the two modalities demonstrated a sensitivity and accuracy, respectively, of 67.6% and 65.9% for PET, and 71.7% and 69% for CT/MRI. In both analyses, no statistically significant difference was found on T-test. In 7/23 patients, HCC showed either loco-regional involvement (n=3) or distant metastases (n=6). All extra-hepatic lesions were properly detected by CHO-PET (accuracy 100%), whereas CT/MRI missed a large part of them (accuracy 58.8%) and this most likely due to the limited field of view during acquisition. In 7 cases (30.4%), PET information determined a change in treatment planning. Conclusion: According to our findings, CHO-PET has a comparable accuracy with CT/MRI in HCC. The principle advantage of the modality appears its ability to detect extra-hepatic lesions, which can lead to treatment modification. Furthermore, in-/opposed-phase sequence (Dixon) used for attenuation correction in MR/PET were evaluated. In all images, the diagnostic confidence in identification of nodules was rated on a 4-point scale (1=certain; 4=uncertain). Additionally, the involvement of each lung lobe (primary/metastatic) was assessed. CT scan in inspiration served as reference. The diagnostic performance of each modality was compared in a lesion-and lobe-based analysis. The diagnostic confidence was compared using Wilcoxon test. Results: 48 lung nodules were evaluated. In the lesion-based analysis, sensitivity (false negative rate) of CTex, VIBEin, VIBEex and Dixon was 77% (23%), 52% (48%), 48% (52%) and 25% (75%). In the lobe-based analysis reflecting the clinical assessment, sensitivity (false negative rate) was 94% (6%), 89% (11%), 89% (11%) and 53% (47%), respectively. In CT and MRI diagnostic confidence was rated higher in inspiration (mean score CTin/CTex 1. Purpose: To evaluate the relationship between quantitative CT-perfusion parameters and tumour volume with glucose metabolism parameters, in staging of lung cancer patients with 18 FDG PET/CT whole body study. Methods and Materials: Thirty-one patients with biopsy-proven lung cancer, referred for cePET/CT staging, were prospectively enrolled in our study. CTp was performed with following parameters: 120 Kv; 80 mAs; scan 30, during intravenous injection of 50 ml of contrast-agent, flow rate: 5 ml/sec. CTp and cePET/CT data were used to calculate a range of tumour vascularity parameters (blood flow, blood volume and mean transit time) and tumour glucose uptake (SUVmax), and finally correlated with tumour volume using a commercially available software. Four patients were excluded due to the advanced stage of the tumour. CT perfusion parameters were then statistically analysed and compared with those of FDG-PET. Results: Perfusion parameters were calculated with a dedicated software (Perfusion 3.0; Advantage; GE) and a quantitative map of arterial perfusion was generated. Patients were divided into two groups according to tumour volume, with a cut-off of 14 cm3. Linear regression was performed among two groups and statistically significant correlations (P < 0.05) were found between BF and SUVmax (negative correlation) and between MTT and SUVmax (positive correlation) for tumours with volume > 14 cm3. These findings may be due to the inadequate blood inflow typical of larger tumours, with a significant increase of anaerobic metabolism and glucose consumption. Conclusion: CePET/CT perfusion is a feasible technique that offers informations related to the biological tumour behaviour that can be used for planning treatment and for an accurate evaluation of tumour response after therapy. retention as PIB positive (PIB+) or PIB negative (PIB-). Data of the unidirectional influx K_1 from a subset of 7 AD patients and 3 controls were used for correlative analysis. Data were analysed using regions of interest (ROI) analysis. Results: We found a strong, positive correlation across brain regions between K_1 and ePIB (r=0.70; p < 0.001). ePIB values were significantly lower in posterior cingulate (p < 0.001) and parietal cortices (p=0.002) in PIB+ subjects compared with PIB-although the group difference were stronger for rCMRglc in cortical areas (p < 0.001). Strong positive correlations between ePIB and rCMRglc were observed in all cortical regions analysed, especially posterior cingulate and parietal cortices (p < 0.001). This study suggests that a single dynamic PIB-PET scan may provide clinical estimates of pathological (amyloidosis) and functional changes (impaired blood flow) in AD. This dual information might be valuable both in early diagnosis of AD and evaluation of treatment strategies, but our results emphasise the need for further research. Purpose: To assess the diagnostic accuracy of diffusion kurtosis imaging (DKI), dynamic susceptibility-weighted imaging (DSC) and short echo time chemical shift imaging (CSI) for grading gliomas, as separate techniques and in a multimodal approach in order to determine the best discriminative parameter (s). Methods and Materials: 35 patients with cerebral gliomas (12 F/23M; age range: 22-78, median age: 55) underwent DKI, DSC and CSI on a 3 T MR scanner. Diffusion parameters: mean diffusivity (MD), fractional anisotropy (FA), mean kurtosis (MK); perfusion parameters: mean relative regional cerebral blood volume (mean rrCBV), mean relative regional cerebral blood flow (mean rrCBF), mean transit time (MTT) and relative decrease ratio (rDR), and twelve CSI metabolite ratios were compared between 22 high-grade gliomas and 14 low-grade gliomas (Mann-Whitey-U, p < 0.05 significance, Bonferroni corrected). Sensitivity, specificity, diagnostic accuracy and optimal thresholds were determined for the techniques separately and combined. Results: MK, MD, mean rrCBV, mean rrCBF, rDR, Lips/Cho, Lips/Cre, Myo/sum and Cre/sum showed statistically significant differences among tumour grades, with mean rrCBF as the best discriminative parameter. The combination of mean rrCBF, MK and Myo/sum to grade gliomas showed diagnostic accuracy, sensitivity and specificity of 100%, whereas combining mean rrCBV, MD and Lips/Cho gave a diagnostic accuracy, sensitivity and specificity of 91%, 93% and 82%, respectively. Conclusion: Combining the parameters mean rrCBF, MK and Myo/sum to determine the glioma grade was pathognomonic in this study. The best performing parameters, when used individually, were found to be MK and mean rrCBF. Additive value of arterial spin labeling in differentiating primary central nervous system lymphoma from glioblastoma multiforme: an observer performance study K. Yamashita, T. Yoshiura, A. Hiwatashi, O. Togao, K. Kikuchi, K. Yoshimoto, H. Honda; Fukuoka/JP (yamakou@radiol.med.kyushu-u.ac.jp) Purpose: To determine whether ASL has an additive diagnostic value to the conventional MR images in differentiating primary central nervous system lymphomas (PCNSLs) from glioblastoma multiformes (GBMs). Methods and Materials: MR images of 48 patients including 12 with PCNSL and 36 with GBM were retrospectively studied. Two independent neuroradiologists took part in 2 reading sessions. In the first session, the observers read only conventional MR images (T1-weighted image, T2-weighted images, post-contrast images, and DWI with apparent diffusion coefficient maps). In the second session, they read ASL cerebral blood flow (CBF) maps along with the conventional images. The confidence level for the diagnosis (PCNSL versus GBM) was graded on a 5-point scale. Interobserver agreement as well as sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were assessed for the two readers. Purpose: Organ-based tube-current modulation (OBTCM) is a technique developed to lower CT radiation dose to anterior dose-sensitive organs. This IRB-approved observational study aimed to establish the location of breast tissue in a female patient in supine position with arms raised over their shoulders. A secondary purpose was to look for possible thresholds of chest diameter and woman's age below or above which the breasts lie in a central location with subsequent possible benefit from OBTCM. Methods and Materials: Informed consent was obtained in 200 consecutive women included. From standard chest CT acquisitions, one 5/5 mm image set with FOV of 500 mm and X and Y coordinates at 0 were obtained. From the gantry rotation centre (x=y=0), the outer and inner angles limiting the breast tissue were measured and compared to the angles (60°), where OBTCM delivers lowered and increased dose to the organs. Results: Outer angles of breast tissue were < 60° for one breast in only two patients. Inner breast angles were > 60° in 14/200 patients for at least one breast. No threshold of chest diameter or age was found to predict a central enough location of the breast for OBTCM to be beneficial. Conclusion: Our data show that the angular position of breast tissue is higher than the limit where reduced versus increased radiation dose is delivered in OBTCM. This system should therefore not be applied to CT chest examinations in adult women lying supine. Purpose: To evaluate the effect of an organ-based tube-current modulation (OBTCM) and bismuth shielding on image quality and breast radiation dose in women undergoing low-dose chest CT. Methods and Materials: Low-dose chest CT was obtained from 80 women, who were randomly assigned to a control, OBTCM, breast shield, or breast shield plus OBTCM group. Axial slice images from aortic arch, carina, and inferior pulmonary vein were used to analyse image quality. Three radiologists scored the image quality in terms of artefact and noise, and then designated the overall image quality as optimal (does not affect the diagnostic accuracy) or suboptimal (affects the diagnostic accuracy). Noise levels were measured in the anterior and posterior lung in each image. A phantom dose study was conducted to measure the radiation dose. Results: Images with artefacts or noise were more frequently obtained in the breast shielded groups. The overall image quality was not significantly different among the four groups. Measured noise levels in the anterior lung were significantly higher in the breast shielded groups than the control group; however, no statistical significance was found among the four groups in the posterior lung. In the phantom dose study, a 16-37.5% dose reduction in the breast was achieved using the breast shield and/or OBTCM protocol. The radiation dose in the female breast may be reduced using the breast shield or OBTCM during low-dose chest CT with acceptable image quality. The OBTCM reduced the radiation dose in the breast without inducing image quality deterioration. the solid parts of gliomas and compared between high-and low-grade gliomas. All the parameters were also normalised to the corresponding values in contralateral normal appearing white matter (NAWM) and compared between high-and lowgrade gliomas. A receiver operating characteristic (ROC) analysis was performed for statistical analysis. Results: There were significant differences in ADCfast and ADCslow values between high-and low-grade gliomas (P < 0.05). The α value was significantly lower in high-grade gliomas than that in low-grade gliomas (P < 0.001). In addition, the ADCfast, ADCslow and α values that were normalised to the values in the contralateral NAWM were all significantly different between high-grade and low-grade gliomas (P < 0.05). Conclusion: IVIM imaging with biexponential and stretched-exponential model is a useful tool in grading cerebral gliomas. The α value may be the best parameter for distinguishing high-from low-grade cerebral gliomas. Purpose: This study aimed to determine which combination of acquisition and iterative reconstruction parameters for low-dose MDCT at low tube voltages yields image quality and diagnostic confidence equivalent to current clinical standards in thoracic imaging. Methods and Materials: Thoracic images of eight sedated and mechanically ventilated pigs were acquired with MDCT during mid-inspiratory breath hold using standard (120 kVp, 180 mAs) and low-dose protocols at low tube voltages (100/80 kVp) and current-time products (120/60/30 mAs). Using lung and soft-tissue kernels, images of all acquisitions were reconstructed with filtered backprojection (FBP); low-dose acquisitions were also reconstructed iteratively (levels 2 and 5, iDose, Philips Healthcare). Three independent blinded readers sorted the resulting 19 image data sets per animal according to diagnostic image quality (best to worst), and sorted images were statistically clustered. Additionally, CT numbers and noise have been determined in lung parenchyma, liver, muscle and aorta of all image data sets. Results: Interreader-agreement was moderate-high (κ=0.56-0.66). For any fixed set of acquisition parameters FBP-images were ranked lowest while those reconstructed iteratively (iDose5) were ranked highest independent of reconstruction kernel. The 19 image series could be clustered into 3 homogeneous clusters of equivalent diagnostic quality: Iteratively reconstructed images acquired at 100 kVp/120 mAs (iDose2/5), 100 kVp/60 mAs (iDose5) or 80 kVp/120 mAs (iDose5) were ranked equivalent to FBP-images acquired using standard protocol. Iterative reconstruction did only affect CT numbers at very low dose (80 kVp/30 mAs) while image noise could be reduced by up to ~60%. Conclusion: Using low-kVp and low-mAs protocols combined with iterative image reconstruction, radiation exposure of thoracic MDCT could be reduced by 50-75%. Purpose: To determine utility of adaptive iterative dose reduction using threedimensional processing (AIDR 3D) for pulmonary nodule identification on low-dose 320-detector-row CT using different scanning methods in phantom study. A chest CT phantom including simulated pulmonary nodule was scanned on a 320-detector-row CT using non-helical wide volume scan (WVS) and helical scans as 64-detector-row CT (64HS) and 160-detector-row CT (160HS) at nine different tube currents. All data sets were reconstructed using AIDR 3D and filter back projection (FBP). To determine the capability of overall identification, two chest radiologists independently evaluated lesion conspicuities by five-point scoring system. At the each scanning method, gold standard was defined as the data set of standard tube current (270 mA) reconstructed by FBP. Interobserver agreements of detection and the capability for radiation dose reduction on each scan method were assessed by kappa statistics and ROC analyses. Results: Interobserver agreements were almost perfect or substantial at all data sets (κ> 0.60). When applied AIDR 3D, area under the curves of data sets equal to or higher than 30 mA on WVS, 40 mA on 64HS, and 40 mA on 160HS had no significant difference with standard data sets (p> 0.05). On the other hand, when applied FBP, radiation dose reduction was limited in comparison with the data sets applied AIDR 3D at all scanning methods. Conclusion: AIDR 3D was more useful for low-dose chest CT examination for nodule screening than FBP, and WVS can reduce more radiation dose than 64HS and 160HS on 320-detector-row CT. Methods and Materials: 50 CTPA studies planned with frontal topogram only (Protocol 1) were compared with 50 CTPA studies planned with frontal and lateral topograms (Protocol 2).Optimal scan length was defined from lung apex to lung base. Excess scan length beyond these landmarks was measured. Mean organ doses to thyroid, liver and stomach were estimated using standard conversion factors. Results: The mean excess scan length was significantly lower in Protocol 2 compared with Protocol 1 (19.5 ± 5.3 mm Vs 39.1 ± 5.3 mm,P < 0.0001). The mean excess scan length below lung bases was significantly lower in Protocol 2 cohort compared with Protocol 1 (7.5 ± 4.2 mm Vs 23.0 ± 4.2 mm,P < 0.0001), as were the mean organ doses to stomach (4.24 ± 0.26 mGy Vs 5.22 ± 0.26 mGy,P < 0.0001) and liver (5.60 ± 0.21 mGy Vs 6.38 ± 0.21 mGy,P < 0.0001).A trend towards reduced over-scanning above the apices in Protocol 2 was observed compared with Protocol 1 (12.0 ± 3.2 mm Vs 16.2 ± 3.2 mm,P= 0.07), with a trend towards lower mean thyroid organ dose in ( Purpose: Volumetric measurement of a nodule is more sensitive in the detection of tumour growth than axial diameter measurement. The purpose of this study was to assess the accuracy of lung nodule volumetry using adaptive iterative dose reduction (AIDR) 3D in comparison with filtered back-projection (FBP) in an anthropomorphic thoracic phantom on 320-detector row CT. Conclusion: Pulmonary haemorrhage during fine-needle lung biopsy is a frequent event. It protects against pneumothorax in patients with pre-existing comorbidities, especially for long needle trajectory, for bleeding greater than 6 mm developing along the needle track. Feasibility and safety of CT-guided percutaneous radiofrequency, microwave or cryoablation of the pulmonary and mediastinal unresectable tumours adjacent to the heart and large vessels C. Pusceddu, L. Melis, G. Meloni; Cagliari/IT (clapusceddu@gmail.com) Purpose: To verify the feasibility and safety of radiofrequency ablation (RFA), microwave ablation (MWA) and cryoablation (CRA) under CT guidance in the treatment of cancer adjacent to the heart and large vessels. Methods and Materials: 27 patients (mean age of 64 years) with unresectable primary and secondary pulmonary and mediastinal tumours (12 NSCLC, 1 invasive thymoma, 1 mesothelial sarcoma and 13 metastases) were treated by CT-guided RFA (14 cases), MWA (7 cases) and CRA (6 cases). All the tumours were in contact or distant from the large vessel wall or the pericardium less than 1 cm. All ablations were performed under conscious sedation and local anaesthesia. Vital signs of the patients were non-invasively monitored continuously. The therapeutic outcomes were evaluated by contrast-enhanced CT after 1 month. In two patients, an electrode is penetrated in the pericardium without any consequences. Results: In all cases, the procedure was technically successful. No intraprocedural arrhythmia occurred. Morbidity consisted of 7 cases of pneumothorax, 3 cases of pleural effusion and 1 case of asymptomatic thickening of the pericardium. In the CT control after 1 month, there was a complete necrosis in 22 cases and a partial (from 70 to 90%) necrosis in the remaining 5 cases. Conclusion: Indifferently from the energy source used to obtain the tumour necrosis, the treatment of the pulmonary and mediastinal unresectable tumours adjacent to the heart and large vessels is feasible and safe because the blood flow cause a "heat-sink" effect adjacent to such structures that prevent undesired thermal damage. Factors influencing local tumour control in patients with neoplastic pulmonary nodules treated with microwave ablation ( were placed in lateral position with the biopsy side down (Group B). Statistical analysis was performed comparing pneumothorax rate between the two groups. The rate of pneumothorax requiring intervention was also assessed. The effect of other variables (patients demographic characteristics, lesion characteristics, lesion distance from the skin and biopsy technique) was evaluated in both groups. Results: 27 pneumothorax occurred in Group A (15.61%) versus 1 (2.44%) in group B (p= 0.025). Pneumothorax requiring treatment was noticed in 10 cases (5.78%) in Group A, versus 0 (0%) in Group B. Emphysema and lesion size were independent risk factors for pneumothorax in Group A. Emphysema was also independent risk factor for pneumothorax necessitating a drainage catheter insertion in Group A. No independent risk factor was recognised for pneumothorax or pneumothorax requiring intervention in Group. Purpose: The aim of this study was to evaluate the feasibility of percutaneous transthoracic needle biopsy of pulmonary nodules under XperGuide CBCT navigation guidance. Between February 2010 to July 2011, we evaluated 70 patients with a pulmonary lesion. All patients had a diagnostic conventional chest CT and after underwent percutaneous transthoracic needle biopsies of pulmonary nodules under XperGuide CBCT navigation guidance.The mean size of the lesion was on average 5.5 cm. Immediately after FNAB an additional CBCT was performed to evaluate any complications; moreover, a follow-up expiratory chest radiograph was obtained. Calculation of radiation dose of the procedure and statistical analysis were performed. Results: Technical success rate was achieved in 100% of cases. Forty-six lesions were diagnosed as malignant, 20 were benign, and 4 were indeterminate. All malignancies diagnosed by FNAB were confirmed by history and imaging. The overall accuracy, sensitivity, specificity, positive predictive value and negative predictive value were 94.2%, 92%, 100%, 100% and 92%, respectively. In the 34 patients with a lesion equal or less to 3 cm undergoing XperCT-guided lung biopsy the average effective dose was 11.14 mSV (range 1. Purpose: This study aimed at reviewing the results and the safety of embolisation in patients affected by haemoptysis of pulmonary arterial (PA) origin. All consecutively patients treated for haemoptysis of PA origin during 12 years (1999 to 2011) were reviewed. Age, underlying disease, and haemoptysis volume were recorded. CT-scan and pulmonary angiography of each patient were reviewed for the description of the PA lesion (aneurysm, false aneurysm, irregularity of the PA or abrupt interruption) and the material of embolisation used for the treatment. Results: Forty-three patients (10 women, 33 men; mean age: 53 years) were treated during this period. Aetiologies were tuberculosis (n=13), lung cancer (n=8), necrotizing pneumonitis (n=8), aspergillosis (n=5), Behcet disease (n=5) and others (n= 4). Five abnormalities of PA were found: pseudo aneurysm of the PA (PAPA) (n=28), aneurysm of the PA (APA) (n=5), irregularity of PA (n=4), early interruption of PA (n=3), one PAVM, and no abnormalities in 2 patients. Materials used for embolisation were coils (n=25), Onyx (n=14) and covered stent (n=2). Two early recurrences, 5 short-term recurrences, and one long term recurrence after embolisation were recorded. They were treated by surgery (n=4) Percutaneous microwave ablation of lung tumours C. Pusceddu, L. Melis, G. Meloni; Cagliari/ IT (clapusceddu@gmail.com) Purpose: To assess the feasibility and safety of percutaneous CT-guided lung tumour microwave ablation. Methods and Materials: 28 consecutive patients (18 men, 10 women, mean age 62 years) underwent CT-guided percutaneous microwave ablation (MWA) of unresectable lung tumours (11 primary NSCLC and 17 metastases) mean size 3.2 cm (2.5-8 cm). The study cohort was selected according to the following criteria: 1) maximum tumour size less than 9 cm in diameter, 2) less than 5 metastatic tumors, 3) patients with a normal coagulation status and 4) provision of written informed consent. All procedures were performed with CT guidance under conscious sedation and local anesthesia. One or two straight microwave antenna (14 or 16-gauge) were placed directly into the tumour for 8-12 minutes. Follow-up included contrast-enhanced CT at 1, 3, 6 months and then at 6-month intervals; stable or reduction size and the absence of tumour enhancement CT images were considered indicative of complete tumour necrosis. Results: In all cases, the procedural was technically successful. Morbidity consisted of 8 cases of partial pneumothorax (28.6%) which were resolved spontaneously within 7 days. At a mean follow-up of 8 months (range 2-15), we recorded a 67.8% of complete response (tumour necrosis = 100%) and a 32.2% of partial response (tumour necrosis range 65%-92%). Our preliminary results show that percutaneous CT-guided microwave ablation is feasible and safe for the treatment of primary and secondary lung tumour. Further follow-up and a prospective controlled trial is necessary to validate the procedure. 1week before the ablation and at 24hours, 3, 6, 9 and 12 months post ablation. Thin section CT Volumetric measurement of the lesions was performed at the same time periods as a second parameter for comparison. The lesion MRI enhancement intensity in each study was estimated, and the ratio to the paraspinal muscle enhancement intensity at the same level was measured (Lesion Muscle Signal (LMS ratio). The correlations between post ablation follow-up CT volume of tumours and CE-MRI LMS ratio at the follow-up periods were assessed. Results: The preablation tumour volumes ranged between 0.30 and 6.1 cm (mean: 1.5 cm³, SD:1.3). LMS ratio 1 was noted in preablation due to high contrast enhancement of the tumour and in 24-h post ablation due to the inflammatory response associated with the thermal ablation and due to tumour residue or progress. Weak correlation was detected between the LMS-ratios and CT-volumetric changes in 24-h post ablation. Strong correlation between the LMS ratios was estimated between the follow-up periods of 3 months (SpearmanR:0.62,p=0.0021), 6 months (SpearmanR:0.66,p=0.001), 9 months (SpearmanR:0.61,p < 0.001) and 12 months (Spearman R:0.7, p < 0.00001). Conclusion: CE-MRI follow-up of the MW ablated lung tumours can be used effectively to assess the tumour response to ablation using LMS ratio as a parameter of assessment. Purpose: To compare image quality between standard-dose filtered back-projection (FBP) and low-dose iterative reconstruction (IR) protocols in computed tomography (CT) of the cervical spine. Methods and Materials: Forty patients investigated by CT of the cervical spine for chronic neck pain and/or cervical radiculopathy were prospectively randomised into two groups: standard-dose CT (120 kVp, 275 mAs) with FBP, or low-dose CT (120 kVp, 150 mAs) with IR. Image noise, signal-to-noise (SNR) and contrast-tonoise (CNR) ratios were measured. Two radiologists, blinded to CT parameters, independently assessed the following anatomical structures at C3-C4 and C6-C7 levels, using a four-point scale: intervertebral disc, content of neural foramina and dural sac, ligaments, soft tissues and vertebra. They subsequently rated overall image quality using a ten-point scale. Volume CT dose index (CTDIvol) and doselength product (DLP) were recorded. Imaging quality of reduced radiation dose lumbar spine CT with iterative reconstruction C.-J. Lin, S. Hung, W. Guo, T. Wu; Taipei/TW (bcjlin@gmail.com) Purpose: The purpose of our study was to investigate the diagnostic accuracy of CT scans of the lumbar spine (CTLS) acquired with lower mAs and kilovoltage reconstructed with an IR algorithm. We prospectively recruited 120 patients for CTLS. Patients were classified into three groups. The radiation dose reduction was set to 50% of the original estimated dose with alternative tube currents and 120 KV in group A, and 100 KV in group B. Images were reconstructed with iDOSE 4 level 4 reconstruction algorithm. For group C, the standard mAs and 120KV with filtered back projection (FBP) algorithm was employed. The SNR of the intervertebral disc (IVD), dural sac (DS) and psoas muscle (PM), and the CNR of the IVD and DS were compared across groups. Two radiologists independently rated the quality of each reduced-dose image as either equivalent ('1') or inferior ('0') to the rater's subjective 'standard' CTLS. Results: There were decreased SNRs of all ROIs in group A but only DS showed statistical significance. There were significant decreased SNRs in IVD, DS, and PS in group B. There was a weak correlation between SNR and BMI in all 3 groups. The CNRs for groups A, B and C were 0.08+0.05, 0.15+0.09 and 0.12+0.06, respectively. The mean image quality scores for groups A, B and C were 0.63, 0.83, and 0.87, respectively. Conclusion: With the aid of the IR algorithm, it is feasible to provide diagnostic CTSL imaging with a 50% radiation reduction using lower mAs. Multidetector computed tomography of the cervical spine: optimisation of iterative reconstruction strength levels Purpose: It was reported previously that trabecular bone structure parameters could add significant information for predicting bone strength beyond bone mineral density. In the past, trabecular bone structure analysis was limited by the spatial resolution of clinically available MDCT scanners. Recent technical improvements have made it possible to determine trabecular bone structure parameters of the spine using clinical MDCT. Therefore, the purpose of this study was to assess trabecular bone structure parameters obtained from clinical MDCT as well as Xtreme-CT (hr-pQCT) as standard of reference and to investigate whether clinical MDCT can predict vertebral bone strength. Methods and Materials: Fourteen thoracic vertebral bodies were harvested from formalin-fixed human cadavers (11 women and 3 men; age: 84±10 years). All specimens were examined using Xtreme-CT (isotropic voxel size of 41 μm³) and a clinical whole body MDCT (interpolated voxel size: 146x146x300 μm³, spatial resolution: 250x250x600 μm³). Trabecular bone structure analyses (histomorphometric and texture measures) were performed in the Xtreme-CT as well as MDCT images. Vertebral failure load was determined in an uniaxial biomechanical test. Results: Xtreme-CT and MDCT-derived trabecular bone structure parameters showed correlations ranging from r=0.60 to r=0.90 (p < 0.001). Correlations between trabecular bone structure parameters and failure load amounted up to r=0.86 (p < 0.001) using the Xtreme-CT images, and up to r=0.79 (p < 0.001) using the MDCT images. Correlation coefficients obtained with Xtreme-CT and MDCT were not significantly different (p> 0.05). The spatial resolution of clinically available whole body MDCT scanners is suitable for trabecular bone structure analysis of the spine and to predict vertebral bone strength. contrast-to-noise (CNR) ratios were measured. Two radiologists independently and blindly evaluated the following anatomical structures at both C3-C4 and C6-C7 levels, using a four-point scale: intervertebral discs, content of neural foramina and dural sac, ligaments, soft tissues and vertebrae. They ultimately rated the overall diagnostic image quality using a ten-point scale. As the strength level of IRs increased, the image noise decreased linearly, while the SNR and CNR both increased linearly (all p²0.001). For the intervertebral discs, the content of neural foramina and dural sac, and for the ligaments, the subjective image quality scores increased linearly with increasing IR strength levels (all p²0.03). In contrast, for the soft tissues and vertebrae, the image quality scores decreased linearly with increasing strength level of IRs (all p < 0.001). Finally, the overall diagnostic image quality scores increased linearly with increasing IR strength levels (both p < 0.001). The optimal strength level of IRs in cervical spine MDCT depends on the anatomical structure to be analysed. For the intervertebral discs and the content of neural foramina, high IR strength levels are recommended. Relationship among facet joint fluid ( years) affected with low back pain underwent MRI of lumbar spine using sagittal T1-and T2-weighted fast spin-echo and axial T2*-weighted gradient-echo sequences. For each level from L3 to S1, disk degeneration was graded using the Thompson scale (1-5), while the FJF was graded as 0 (absent), 1 (monolateral), or 2 (bilateral): per-patient disk degeneration and FJF were calculated summing the scores of the 3 spine levels. Spearman correlation coefficient, multivariate regression analysis, Friedman McNemar tests were used. Data were reported as median and interquartile interval (II). The degeneration of L3/L4 (median 3; II 2-3) was lower than that of both L4/L5 (median 3; II 2-3; p=0.017) and L5/S1 (median 3; II 3-4; p=0.002). The FJF of L5/S1 (median 0; II 0-1) was lower than that of both L3/L4 (median 1; II 0-2; p=0.002) and L4/L5 (median 1; II 0-2; p=0.019 Near-perfect correlations of SUV values were found for the myocardium (SUVmax/ mean: R = 0.98/0.98); good correlations were found for the liver (R = 0.6/0.7), subcutaneous fat (R = 0.6/0.8), bone marrow (R = 0.6/0.5), psoas muscle (R = 0.6/0.5) and the SUVmax of the blood-pool (R = 0.6). Correlations between MRAC and CTAC were non-significant for SUVmax and SUVmean of the lung and the SUVmean of the blood-pool. The mean SUVmax and SUVmean in MRAC-PET compared to the respective CTAC values was significantly lower in all organs (p < 0.05) but in the myocardium (SUVmax) and the psoas muscle (SUVmax/mean). Results: Sixty-three patients were referred for a pre-treatment FDG PET-CT; age range was 21-78 years (mean age 47 years). PET-CT had a major impact on patient management in 32%, a minor impact in 8% and no impact in 60%. In patients with a major impact; 12 had unsuspected nodal involvement, 5 had occult metastases, 2 had synchronous tumours and 1 had negative nodes on PET-CT. These findings either altered radiotherapy treatment planning or treatment intent. During the follow-up period until August 2012, 25% developed disease recurrence following completion of therapy (11% isolated local relapse and 14% distant (± local) disease). Conclusion: FDG PET-CT can have a major impact on patient management in locally advanced cervical carcinoma, by detecting occult disease or characterising indeterminate findings on MRI, resulting in an alteration in radiotherapy treatment planning and/or treatment intent in up to one-third of patients. Is there a role for standard uptake value in the prognostic evaluation of lung nodules? Purpose: We report about our approach in imaging patients with cervical cancer using an integrated simultaneous PET/MRI device. Goals were the introduction of a stable and effective protocol for whole body and dedicated pelvic examination and rating of image quality. Methods and Materials: Ten patients with primary (n=4) cervical carcinoma or tumour recurrence (n=6) were included. Patients underwent a simultaneous PET/ MR, PET/CT and conventional MR examination. MR and PET image quality were rated on a Likert score system (0-4) by three radiologists and a nuclear physician. PET data were simultaneously visually compared by two nuclear physicians and a radiologist. Purpose: BRCA1 and BRA2 mutation carriers may be more susceptible to radiationinduced cancer because of their role of tumour suppressor genes in radio-induced DNA damage repair and signalling. Heterozygous mutations of A TM , a major kinase initiating the response to radio-induced DNA double-strand breaks, is likely to be involved in lymphoma as well as in breast cancer in high-risk patient (HRP) treated for a Hodgkin disease. Thus the standard two-view mammographic screening annually recommended with MRI in HRP must be adapted. Recent literature data were analysed. Individual radiosensitivity was assessed by radiobiological effects and epidemiological studies. Radiophysical and radiological mammographic data about calcifications detection and reduction of exposures were also taken into account. High-resolution diffusion-weighted imaging of pancreatic ductal adenocarcinoma using 2D reduced field of view single-shot echo planar imaging at 3.0 Tesla C. Ma, Y. Li, H. Wang, S. Chen, J. Lu; Shanghai/CN (mengqihi@gmail.com) Purpose: To demonstrate the feasibility of high-resolution DWI of pancreas using 2D reduced field of view (RFOV) single-shot echo-planar sequence in the evaluation of pancreatic ductal adenocarcinoma. Methods and Materials: 50 normal volunteers and 50 patients with histopathologically proven pancreatic ductal adenocarcinoma by surgery were included in the study. High-resolution DWI of pancreas was obtained using a multi-section 2D RFOV single-shot echo-planar sequence on the axial plane (FOV 16×8 cm 2 , matrix 128×64). ADC of the normal pancreas in control group and pancreatic ductal adenocarcinoma group were measured. Mann-Whitney U-test has been used to compare ADC values between tumoral tissues and normal pancreatic tissues of the volunteers. Results: On the high-resolution DW images, all pancreatic ductal adenocarcinoma demonstrated high signal intensity relative to the surrounding pancreatic parenchyma. The mean and standard deviations of the ADC values (×10 -3 mm2/s) were as follows: pancreatic ductal adenocarcinoma (n = 50), 1.53 ± 0.26 (1.02 -2.23), and normal pancreas in normal volunteers (n = 50), 1.98 ± 0.25 (1.60 -2.73). ADC of the pancreatic ductal adenocarcinoma were significantly higher compared with those of normal pancreas (U = 230.000, P = 0.000). Conclusion: RFOV DWI shows advantages in higher resolution (1.25×1.25 mm 2 ) and blurring reduction compared to full FOV DWI of the pancreas. It makes a statistically significant difference on the ADC measurements of the pancreatic ductal adenocarcinoma when comparing to the control group. This approach is promising to benefit the early diagnosis of pancreatic cancers. Purpose: To prospectively evaluate the application of ARFI implemented with virtual touch tissue quantification in the study of pancreatic cystic lesions, using different analysis methods, compared with the final diagnosis (pathological or by MRI/EUS findings). Methods and Materials: 38 patients with pancreatic cystic focal lesion (diameter > 3 cm and located at a depth < 5.5 cm) were included in the study and underwent conventional US. For every patient 5 measurements with virtual touch quantification ROI were performed. In order to distinguish mucinous (potentially malignant) from serous cystic lesions (mainly benign) the result "XXXX/0" was considered meaning simple liquids (reportable to water), and the accuracy of virtual touch tissue quantification in differentiating cystic-pancreatic lesions was calculated. To consider the lesion as containing complex fluids (potentially mucinous), two different reading methods have been applied: at least two numerical values when performing five measurements; prevalence of numerical values irrespective of the number of measurements. Sensitivity, specificity, positive and negative predictive values and accuracy were calculated for the differential diagnosis between mucinous versus non-mucinous cystic lesions. Results: Sensitivity, specificity, PPV, NPV and accuracy in the group of cystic lesions using the first reading method were, respectively, 68.8%, 77.3%, 68.8%, 77.3%, 73.7%. Sensitivity, specificity, PPV, NPV and accuracy in the group of cystic lesions using the second reading method were, respectively, 37.5%, 100%, 100%, 68.8%, 73.3%. Conclusion: ARFI with virtual tissue touch quantification can have a role in noninvasive characterisation of pancreatic cystic lesion during the conventional US examination. Purpose: To evaluate the efficacy of CT perfusion for detection of malignancy in pancreatic masses. Methods and Materials: 27 patients (pts) who presented with a mass in the pancreas were enrolled in this Institute Review Board-approved prospective study after informed consent and underwent biphasic CECT with perfusion CT of the pancreas. Pts were followed up and results of cytopathological diagnosis obtained. Final diagnosis consisted of malignancy (adenocarcinoma) in 11, various benign masses in 13 and neuroendocrine tumour in 3 pts. Control group consisted of 15 pts who were referred for CT for an indication other than pancreatic pathology. 11 perfusion parameters were calculated using software MIStar 3.2 (Apollo imaging software). CT perfusion parameters were compared between the control and study groups as well as results of cytopathological diagnosis using ANOVA and Dunnett 2-sided t-test for statistical analysis. Results: All perfusion parameters except extraction (E) were significantly different between adenocarcinoma and benign groups. All perfusion parameters except permeability (PS) were also statistically significantly different between adenocarcinoma group and controls. Blood flow (BF), blood volume (BV), extraction fraction product (EFP), PS and peak enhancement intensity (PEI) showed decreasing trend in values, whereas rest of the parameters showed an increasing trend from normal to benign to adenocarcinoma. Neuroendocrine tumours had different perfusion values with significantly elevated BF, BV, PEI and earlier time to peak (TTP). One patient with pancreatic tuberculosis had perfusion values paralleling adenocarcinoma but with relatively earlier TTP. Conclusion: Perfusion CT seems to be a useful tool for differentiating between malignant and benign pancreatic masses. Comparison After the acquisition of axial T1w and T2w sequences and coronal MRCP, diffusionweighted MR imaging was performed using an axial respiratory-triggered spin-echo echo-planar sequence with multiple b values (150, 500, 1000, 1500 sec/mm²) in all diffusion directions. ADC value was calculated by using a dedicated software fitting the curve obtained from the corresponding ADC for each b value. Fitted ADC values were calculated by two observers in conference for each cystic pancreatic lesion and for normal pancreatic parenchyma. Imaging results were correlated with surgery, ERCP, and/or imaging follow-up. Results: Final diagnoses included intraductal papillary mucinous tumour (IPMT) (n=58), serous cystoadenoma (n=18), and mucinous cystoadenoma (n=10). Fitted ADC value was 1.33x10-3 mm2/sec for normal pancreatic parenchyma, 3.10x10-3 mm2/sec for IPMT, 2.57x10-3 mm2/sec for serous cystoadenoma, 2.93x10-3 mm2/ sec for mucinous cystoadenoma. Fitted ADC values were significantly higher in mucinous neoplasms than in serous cystoadenomas (p < 0.05). Our results suggest that diffusion-weighted 3 T MR imaging with b-multiple SE-EPI may be helpful to differentiate mucinous from serous cystic pancreatic lesions. Further investigations in larger series of patients are necessary to confirm our data. Purpose: Cardiac magnetic resonance imaging (CMR) using a comprehensive approach consisting of adenosine perfusion and late gadolinium enhancement (LGE) at 1.5 Tesla has established for detection of relevant coronary artery disease (CAD). Little is known about the potential advantages of 3 Tesla CMR to detect relevant CAD. Aim of our prospective study was to compare a clinical routine CMR protocol performed at both 1.5 and 3 Tesla in patients with suspected CAD undergoing coronary x-ray angiography. Methods and Materials: 52 patients (62.3±10.2 years) with suspected CAD were included into the study. All patients were scanned at both 1.5 and 3 Tesla including functional imaging, adenosine stress and rest perfusion, and LGE. CMR images were analysed by two blinded readers in consensus. X-ray angiography served as the reference method. Results: Diagnostic accuracy of the combined analysis of perfusion and LGE imaging yielded better values at 1.5 and 3 Tesla than the analysis of perfusion images alone. Sensitivity and specificity at 3 Tesla were superior to 1. Purpose: The purpose of this study was to evaluate the prevalence of pathological cardiac MRI findings in subjects with mild coronary calcifications. Methods and Materials: 101 asymptomatic volunteers were selected from a large population-based screening study in accordance with their Agatston calcium score (group 1: Agatston score: 0, n = 51, age 60.10 +-6.41; group 2: Agatston score: 1 -100, n = 50, age 63.9 +-6.33). All subjects underwent cardiac MRI at 1.5 T. The MRI protocol included a) functional assessment of the left ventricle, b) assessment of adenosine stress-/rest perfusion and c) quantification of late gadolinium enhancement (LGE). Results: A stress-induced perfusion deficit was present in 1/101 subjects (1.0%), whereas LGE was seen in 17/101 subjects (16.8%). Group 1 (Agatston score: 0): In this group none of the subjects showed a perfusion deficit, whereas in seven subjects LGE was observed (13.7%). Two of the seven subjects showed an ischaemic-type pattern of LGE (3.9%) indicating chronic infarction. Group 2: median Agatston score of group 2 was 19 (Q1, 11; Q3, 43). In this group a perfusion deficit could be observed in one subject (2.0%), whereas LGE was observed in ten subjects (20.0%). However, all of these LGE patterns were assessed as non-ischaemic. The prevalence of stress-induced myocardial ischaemia in subjects with mild coronary calcifications score is low, whereas the frequency of non-ischaemic LGE is relatively high. Long-term follow-up will clarify whether these cardiac MRI findings contribute to cardiovascular risk stratification in asymptomatic subjects. Purpose: To determine the feasibility of CT-based myocardial perfusion imaging to differentiate ischaemic and infarcted myocardium as compared to magnetic resonance imaging (MRI). We prospectively enrolled subjects with suspected coronary artery disease, who underwent adenosine-mediated stress myocardial perfusion imaging by dynamic dual-source CT (100 kV, 320 mAs/rot) and 3 T-MRI. Myocardial blood flow and volume (MBF and MBV, respectively) were derived from CT images, using a model-based parametric deconvolution method for 16 myocardial segments. These were related to perfusion defects visually assessed during rest/stress and delayed MRI acquisitions. Conventional measures of diagnostic accuracy and differences in MBF/MBV were determined in a blinded fashion. Results: Among 41 enrolled subjects, 31 (mean age 70 ± 9 years, 74% men) completed the protocol. The prevalence of ischaemic and infarcted segments detected by MRI was moderately high (11.6% and 12.4%, respectively Purpose: Patients with extra-cardiac arterial disease (ECAD) are at high risk of coronary heart disease. We examined the prevalence of silent, significant coronary artery disease in patients with stenotic or aneurysmatic ECAD. Methods and Materials: Cardiac asymptomatic ECAD patients without contraindications for computed tomography (CT) and magnetic resonance imaging (MRI) underwent coronary CT angiography (cCTA) and adenosine perfusion MRI (APMR). Calcium scoring was performed based on non-contrast CT. CCTA was positive when ³50% lumen diameter stenosis in a coronary artery was found. Patients were referred to a cardiologist when cCTA showed a stenosis in the left main coronary artery (or equivalent), or when APMR showed inducible myocardial ischaemia. Results: In total, 115 patients (mean age 65 yrs; 76% male) were included. Patients were divided into 2 categories: stenotic (N=87) and aneurysmatic ECAD (N=28). CCTA was positive in 38% in stenotic and 29% in aneurysmatic ECAD. No cCTA was performed in 20% due to excessive calcium. Two patients, 1 stenotic and 1 aneurysmatic ECAD had left main stenosis. APMR was positive in 12% in stenotic and 11% in aneurysmatic ECAD. Eighteen percent of stenotic and 21% in aneurysmatic ECAD have been referred to the cardiologist. A cardiac intervention was performed in 43% of stenotic and 33% in aneurysmatic ECAD. Significant stenosis or high calcium score was found in 58% in stenotic, compared to 50% in aneurysmatic ECAD. None of these outcomes were statistically significant. Conclusion: Silent, significant coronary artery disease is highly prevalent in patients with ECAD, either stenotic or aneurysmatic. Purpose: To evaluate non-linear image blending in comparison with linear image blending in late phase dual-energy computed tomography (DECT) for the visualisation of delayed myocardial contrast enhancement in acute myocardial infarction (MI) and to identify optimal parameters for non-linear image blending. Methods and Materials: Acute reperfused MI was induced in seven pigs by temporary occlusion of the left anterior descending or left circumflex artery. Two hours after reperfusion contrast-enhanced late phase DECT (80 kV/140 kV) was performed. DECT data were post-processed with linear and non-linear image blending techniques. Contrast and percentage signal difference between healthy and infarcted myocardium as well as the blood pool of the left ventricle were computed for the linear and non-linear techniques including the low and high kV images. Data were compared using repeated measures ANOVA and post hoc t-tests. Results: Non-linear blending showed the highest signal differences for all contrasts and analyses. Repeated measure ANOVAs confirmed these differences to be statistically significant for the different post-processing techniques (p-value ranging from < 0.001 to 0.003). Paired-samples post hoc t-tests proved the significance of these results (p-value ranging from < 0.001 to 0.037). The ideal settings for nonlinear image blending can be deduced from the CT values of the regions of interest in the linearly blended images with the weighting factor 0.3. Conclusion: Non-linear image blending improves the visualisation of acute MI in DECT. Non-linear image blending in late phase DECT of acute MI is superior to linearly blended images as well as source images obtained at 80 kV or 140 kV. Purpose: To assess feasibility and reliability of the Juvenile arthritis MRI scoring system (JAMRIS) for the wrist to evaluate early-stage disease activity, and to compare reliability of JAMRIS for the wrist for early-stage disease with the validated paediatric-targeted MRI scoring system (PTMRIS) for children with more progressive stage of disease. Methods and Materials: MRI datasets from 20 juvenile idiopathic arthritis (JIA) patients with wrist involvement were evaluated independently by three readers using JAMRIS and PTMRIS. Assessment of early-stage disease activity in JAMRIS was achieved through extending soft tissue scoring items (synovial hypertrophy, tenosynovitis) and specifying the grading of bone scoring items affecting < 25% of the bone (bone marrow changes, bone erosions). Intraclass correlation coefficient (ICC) or Cohen's kappa was used to assess inter-and intrareader reliability. ICC of each JAMRIS scoring item was compared with the ICC of its equivalent in PTMRIS. Results: Three JAMRIS scoring items (synovial hypertrophy, bone marrow changes and bone erosions) showed moderate to good reliability: ICC varied from 0.62 to 0.89 for interreader reliability and 0.28-0.95 (reader 1) and 0.88-0.97 (reader 2) for intrareader reliability. Reliability of tenosynovitis was moderate to poor with Cohen's kappa varying from 0.24 to 0.48 (interreader) and 0.41 to 0.64 (intrareader). JAMRIS and PTMRIS showed similar results of interreader reliability. Conclusion: Early JIA disease activity in the wrist can be reliably evaluated with three-out-of-four features of the simple and accurate JAMRIS scoring system. Correlating clinical disease assessment and responsiveness to change will be needed to validate JAMRIS for the wrist as outcome measure and disease monitoring tool. showing equivocal findings or a bone injury outwith the clavicle. In those found to have clavicle fractures, 32 follow-up radiographs were performed in 26 individuals (4%). Orthopaedic fixation was not performed in any of the identified cases. Conclusion: Despite a high pick-up rate of fractures, clavicle radiographs do not appear to substantially alter clinical management. In our centre, immobilization is the usual management for suspected traumatic clavicle injury, regardless of radiographic appearance. We suggest that, in the context of an experienced paediatric Emergency Department team, radiographs are reserved for patients causing concern at follow-up and are not required routinely at presentation. (AN) is an eating disorder characterised by alteration of bone metabolism (osteopenia) and of body composition (reduction and abnormal distribution of fat mass-FM and lean mass-LM), due to oestrogen deficiency and self starvation. The aim of our study was to address bone metabolism and body changes in a cohort of patients with AN by using Dual-energy x-ray-Absorptiometry (DXA). Prospective study on 75 patients with AN, submitted to DXA at baseline-T0 and after 12months-T12. We evaluated total and regional FM and LM percentages, as well as lumbar bone mineral density-BMD and Z-score, linking them to clinical variables: menarche/amenorrhea/hormonal therapy and physical activity. Results: Among the 46/79-58.2% patients that completed the study the T0 clinical condition was as follows: BMI=16.4±1.4 kg/m2, low levels of FM percentage (21.7±5.7%), osteopenia (Z-score:-1.21±1.27SD, with higher values related to physical activity-p=0.001). At T12: significant increase in BMI-p=0.001, with LM reduction and FM increase (more evident in the trunk-p < 0.001); regarding bone, no significant changes were observed, though a tendency in terms of improvement associated with resumption of menses was manifested. After one year, significant conclusions on bone metabolic condition could not be reached. By contrast, weight recovery was associated with the increase of FM and a distortion of its distribution, more evident in trunk region (potential and adjunctive risk factor for the relapse of the psychiatric condition). The complexity of these clinical findings suggested that DXA, a low-dose and low-cost technique, could have a key role in long-term monitoring of AN patients. Replacing conventional spine radiographs with dual-energy x-ray absorptiometry (DXA) in children with suspected reduction in bone density E. Adiotomre, L. Summers, P. Broadley, I. Lang, G. Morrison, A. Offiah; Purpose: Children have greater lifetime risks of radiation-induced complications compared to adults. In children with osteogenesis imperfecta conventional radiographs are obtained to assess spine morphometry, while DXA assesses bone density. In adults DXA is used for both. We aim to establish whether iDXA can replace spine radiographs in assessment of paediatric vertebral morphometry. Methods and Materials: An 18-month prospective study of 200 consented children (5 to 15 years old) with and 50 without suspected reduction in bone density, who had lateral spine radiographs and lateral DXA scans on the same day, was conducted. Three observers will independently assess all images (blinded to corresponding results of radiographs and DXA) using a modified ABQ technique. 100 random images will be interpreted twice. Diagnostic accuracy and inter-and intraobserver reliability of DXA will be compared to the gold standard of radiography. Patient/carer experience, DXA radiation dose compared to radiographs and health economics will be assessed. Results: Interim analysis of the first 50 recruited patients showed 26 had 1 or more vertebral fractures. The fracture detection sensitivity for DXA was 62.7% and specificity 87.8%. The overall accuracy for vertebral fracture detection with DXA was 83.5%. The overall agreement between radiographs and DXA was 68.7%. The modified ABQ technique has limitations in children and a more reliable scoring system is required. Compared to radiography DXA does not appear to be worse for morphometry and given the reduced dose and comparable image quality, DXA should be recommended for morphometry in children pending more robust analyses. (n=221) had DDH necessitating 3 or more ultrasound examinations, of which 23% (n=50) required treatment. There was one case of missed hip dislocation, representing 0.0001% of unexamined patients. No patients with IIC hips at presentation with conservative management represented with a dislocated hip. Radiographs in the treated group demonstrated a satisfactory outcome in 94%. One patient represented with a dislocated hip following erroneous cessation of harness treatment and went on to develop early avascular necrosis. Two patients were lost to follow-up. Conclusion: A delayed approach to managing DDH in infancy allows those patients with ultrasonographically immature hips the opportunity to develop normally without invasive treatment and identifies patients which would most benefit from treatment. This reduces the demand on resources that a DDH screening programme which treated patients more promptly would incur. Within the same financial constraints, this allows more patients to be selected for screening. A delayed approach results in a satisfactory outcome with no subsequent late dislocation in those treated appropriately. Purpose: In cases of hip complaints in the paediatric population it is common practice to acquire both AP and frog-leg lateral (FL) radiographs. The combination of these views has a diagnostic yield, but also doubles the radiation exposure. In our observation, the FL view alone is often diagnostic. We therefore investigated the diagnostic accuracy of obtaining a solitary FL view as compared to a combination of the AP and FL views. Methods and Materials: Children aged 2-15 years who were sent in for hip radiographs between September 2007 and January 2011 were included in the study. Cases of related trauma or a history of hip pathology were excluded. Radiographs were retrospectively assessed by two independent radiologists. Radiologists were blinded for the AP radiograph while assessing the FL radiograph and vice versa and radiographs were presented in a random order. We used the Kappa test to calculate interobserver agreement and agreement between the assessment of both views and the solitary FL view. Results: 524 children (mean age 8.1 yrs) met the study criteria and were included for analysis. 477 children had a normal exam and 47 were considered abnormal. Calculated interobserver agreement using the Kappa test was 0.96. Agreement between the solitary FL view and the combination of the AP/FL view was 0.989. The diagnostic accuracy of the FL radiograph in case of hip complaints in children is as high as the current standard of both AP and FL views. and healthcare centres. Statistical analysis was made using descriptive statistics, Mann-Whitney and Kruskal-Wallis tests in order to verify correlation between items. Results: Radiographers consider that it is essential the implementation of a quality control program in the radiology department, but there is lack of information in this field, and 53.2% do not know what a quality control program is. 96% of radiographers claim their institutions do not have quality control programmes or accreditation. However, 25.5% had received education on quality and 85% make regular personnel radiation measures. Also, despite there is no lack of radiological protection equipment in most departments, 77.4% claim they are in poor condition. Conclusion: Quality control programs are essential to the radiology department and radiation safety guidelines must be implemented. Despite that some radiology departments have radiological protection equipment often applied by radiographers, their effectiveness and condition must be checked regularly. Purpose: Applying control charts to demonstrate the importance of implementing a radiological imaging quality control system. Research conducted in a public hospital comprising a total of 1110 randomly selected exams (640 chest studies, 340 abdominal studies and 130 foot studies) grouped in 37 samples, each one with 30 exams. The conformities and non-conformities found were used to establish three types of quality control charts based on the evidence collected, namely the proportion of conformities and non-conformities (p), the total number of non-conformity exams (np) and the total number of non-conformities in each sample (c) in order to suggest corrective actions for improvement. Results: Considering all exams, 57% are non-conformities and 43% are within conformities. Of 640 chest studies, 40% were within conformities and 60% were non-conformities; of 340 abdominal studies, 46% were within conformities and 54% were non-conformities. Foot studies had an almost even distribution of conformities and non-conformities with 51 and 49%, respectively. Conclusion: This research allowed the identification of different types of nonconformities found in radiological images which have impact on imaging quality. Therefore, the existence of adequate quality control of radiographic imaging is essential. A review of diagnostic imaging frequency to aid research exploring the issue of consent for higher dose paediatric examinations J.L. Portelli 1 , J. McNulty 2 , S. Mohan 2 , P. Bezzina 1 , L. Rainford 2 ; 1 Msida/MT, 2 Dublin/IE (jonathan.portelli@um.edu.mt) Purpose: Concerns have grown in recent years in relation to potential radiationrelated risks associated with diagnostic imaging examinations performed on paediatrics (< 18 years). This retrospective cohort study aims to provide an insight into the use of potentially higher dose computed tomography (CT) and fluoroscopyguided examinations in paediatrics, in two national clinical centres of comparable catchment areas in Malta and Ireland. Methods and Materials: Retrospective data, of higher dose diagnostic imaging examinations performed in paediatrics in 2011, was collected from departmental logbooks and radiology information system (RIS) databases of the participating centres. This data included details pertaining to patient's age, type of examination and relevant examination kV, mAs, DAP, fluoroscopy time, CTDI and DLP (if available). Data were categorised according to age and examination type, and effective dose estimates for CT were calculated. Results: In 2011 alone, at least 2,093 CT examinations, 1,532 fluoroscopy-guided procedures and 438 cardiac catheterisation interventions were performed on paediatrics across both centres. Particular complex fluoroscopy-guided interventions had an associated DAP exceeding 10,000cGy.cm2, while effective dose estimates for CT examinations indicated that some paediatric patients may receive a moderate (> 3-20mSv) or high radiation dose (> 20-50mSv). Conclusion: Paediatric patients may undergo examinations that potentially involve a high dose of ionising radiation. Further research to explore the debated issue of benefit-risk communication and consent in paediatric imaging is therefore justified and encouraged, particularly as the study's findings also indicate that repeat or multiple imaging examinations of different anatomical areas are commonly performed in CT. Purpose: To estimate the lifetime attributable risk (LAR) of cancer incidence for individual organs following radiation exposure during PCI in the context of two opposite sides of angiographic spectrum of coronary occlusive disease: ST-elevation myocardial infarction (STEMI) and chronic coronary total occlusion (CTO). We identified all consecutive patients treated with PCI for STEMI (n=555) and for CTO (n=543) in a tertiary care centre in 6 years. The LARs of cancer incidence for six organs (colon, liver, lung, red bone marrow, stomach and thyroid) were estimated using the Biological Effects of Ionising Radiation (BEIR) VII model. The estimated LARs of cancer incidence for individual organs was found to markedly increase as the age of the patient decreases and was significantly higher for the lung (additional risk up to 18/100.000 person's lifetime exposure in CTO and 9/100.000 in STEMI patients, respectively, p < 0.0001) and for the red bone marrow (up to 3.5/100.000 and 1.5/100.000, respectively, p < 0.0001). In both the groups, the estimated LAR of cancer incidence for stomach, colon, liver and thyroid was similar and very low. Conclusion: In PCI procedures, the lung was the organ with the highest radiation absorbed. According to BEIR-VII model, the number of additional cancer cases for individual organs was on average two times higher in patients treated with PCI for CTO and the highest LARs were for lung and red bone marrow cancers. Project retake: quality assurance of radiation hygiene by maintaining image quality Purpose: To reduce the extent of retake while maintaining image quality. The research was conducted in two digital x-ray labs, data for six months were analysed by quantitative method. Patient data: id, information of retakes was stored at modality, post-examination. 750 random patients, undergoing standard x-ray examinations, were selected each month. A standard examination contains two or three exposures, front oblique and/or lateral. Radiographers were encouraged to choose a cause for retake. Analysis contained: type of examination, number of projections, number of exposures and retake reason per patient. The causes are systemised in the modality, ready to select if there is a retake. Reject options were radiographer, patient or student failure. There was an average of 234 retaken images out of 750 examinations. That is to say, 30% margin of error. 28% of the standard examinations were retakes; the reject option was radiographer failure. Rest 2% was patient or student failure. As a result of this a PGMI test is established for the digital labs to test quality assurance. Results after this quality assurance give a reduction of 110 retakes per month. A reduction of 50% retakes due to radiographer failure. Conclusion: Environment, method, monitoring and feedback, influence radiographer result and radiation dose to patients. Radiographers using digital x-ray need quality assurance as in mammography. PGMI usage will give feedback to maintain image quality and reduce radiation dose. Implementation Purpose: To evaluate the importance that radiographers give to quality control programs, radiological protection and the verification of radiological protection criteria. A 30-item quality control assessment and radiological protection questionnaire was applied to radiographers working on public hospitals S285 A C D E F G B Saturday viability was tested by performing two tests on the lateral position of the lumbar spine, with a phantom. The results obtained using the aluminum filter resulted in a reduced variation in relative dose rate (9%) compared to not using the filter as well as a 32% reduction in dose to the entrance surface of the skin. Regarding the image quality, it has been found that the use of filter presents significant reasons the optimisation of this parameter. These results indicate that the use of the filter should be considered as a good practice in the lumbar spine radiography to achieve dose reductions. Antero-posterior (AP) pelvic radiography: collimator errors and their effects on radiation dose H. Brookfield 1 , A.S. Manning-Stanley 2 , A. England 1 ; 1 Liverpool/UK, 2 Salford/UK (aengland@liverpool.ac.uk) Purpose: To investigate the range of collimator errors in x-ray rooms and to calculate their possible effects on the radiation dose for AP pelvis examinations. A collimator test tool was suspended at three heights (14, 21 and 28 cm) above the table bucky in nine x-ray rooms. Heights corresponded to the patient thickness (mean, ±2SD) in 100 patients. The x-ray beam was visually collimated to the inner boundary of the test tool and exposed to radiation. Differences between the visualised field size and the resultant x-ray field size (corrected for magnification) would indicate any collimator errors. On the pelvic phantom minimum textbook collimation was set and then changed in order to simulate a range of possible collimator errors. Phantom examinations used a standard technique with exposure termination using outer AEC chambers. Dose-area-product (DAP) was recorded. Results: Out of nine x-ray rooms all but one produced a smaller irradiated area than was visually set. Errors ranged from a 16% reduction in irradiated field size to a slight over irradiation by 0.4%. With the possibility that these errors could be larger in other institutions a range of (-27% to +18%) errors were simulated. Increasing the field size by 1 cm (superior/inferiorly) increased the DAP by 5%. Laterally, a 1 cm increase caused a 4% rise. Increases of 1 cm in both planes raised DAP by 4%. In this study collimator errors were minimal and favoured under irradiation. Small errors can affect DAP and are more dose significant in the superior/inferior plane. Breast shielding significantly reduces breast dose during lumbar spine radiography N. Mekiš, D. Žontar, D. Škrk; Ljubljana/SI (nejc.mekis@zf.uni-lj.si) Purpose: As use of protective shielding for the patient in conventional radiography varies widely in practice, the study aimed at providing objective answer about the effect of lead rubber sheet shielding for a specific case of breast dose during the lumbar spine radiography. Influence of the body mass index on the breast dose was also investigated. The study was conducted both on an anthropomorphic phantom and on a cohort of 100 female patients, randomly divided into two equal groups. In both cases lumbar spine imaging was conducted in AP and lateral projection with and without the lead shield (in case of the patient study the shielding was used in one group only). The dose was measured by thermoluminescent dosimeters (TLD) placed at the centre of the breast. Results: Using the lead shielding dose to the right breast was reduced from 0.45±0.25 mGy to 0.09±0.07 mGy (p < 0.001) and the dose to the left breast from 0.26±0.14 mGy to 0.06±0.04 mGy (p < 0.001), compared to the unshielded breast. On average, the breast dose was reduced by approximately 80%. No correlation between the body mass index (BMI) and the breast dose was found. Conclusion: Based on the results, we can conclude that the use of breast shielding is recommended in lumbar spine radiography. Despite the low-dose exposure even without shielding, the dose can be further reduced. Moreover, the quality of the x-ray image is not affected by the use of the lead shield. An approach for Portuguese diagnostic reference levels for bedside chest radiography A. Sousa, S. Serém, J. Santos, G. Paulo; Coimbra/PT (sarajoanacs@hotmail.com) Purpose: Bedside chest radiography represents the most commonly performed examination. Taking into account the different protocols and equipments it is important to develop diagnostic reference levels, in order to promote a patient safety culture and consequently health care best practice. This research was carried out in two imaging department centres from the same geographic region (Hospital A and Hospital B). In phase one, the exposure parameters and entrance skin dose (ESD) value of 40 bedside standard patients' chest radiography were collected. To optimise the obtained dose values in Hospital B more 15 bedside standard patients' chest radiography were collected on phase two, using parameters of Hospital A, that had already went through an optimisation process. Results: In phase one Hospital A ESD value was statistically lower (16.45 μSv) in comparison to Hospital B (21.94 μSv). In phase two Hospital B decreased significantly the ESD value (17 μSv) in comparison with the phase one, but with no significant differences with Hospital A. Conclusion: Patients in Hospital B at phase one were 25% more exposed to ionising radiation than patients from Hospital A for the same procedure. The implementation of optimised protocols at phase two reduced the dose levels in 29.1% in the Hospital B. The regional DRL for bedside chest radiography was set at 17 μSv. An investigation into the relationship between the exposure index value and image quality M.-L. Butler, L. Rainford; Dublin/IE (marielouise.butler@ucd.ie) Purpose: 'Exposure creep' is a documented phenomenon in computed radiography (CR) where radiation dose is given unnecessarily to patients due to CR's processing capabilities. Manufacturers have responded by developing an exposure index (EI), which is a measurement of detector dose and hence relates to noise in the image. This study aimed to identify how the EI value relates to image quality in clinical practice. Methods and Materials: Three imaging suites and five radiographic examinations were included: ankle and wrist series (antero-posterior (AP) and lateral); AP and lateral lumbar spine; AP pelvis and postero-anterior (PA) chest projections. In total, 306 examinations were documented with a minimum of 10 patients for each projection. Twelve patient images representative of each projection were selected according to their Agfa lgM value; 3 low, median and high lgM values and images recording 3 lgM values closest to the manufacturers' guidelines. Three observers, experienced radiographers (minimum of 6 years working clinically), reviewed the images for noise and overall exposure of the image. In addition the observers indicated what EI value they judged appropriate to image presentation. Results: No significant difference in image quality was noted across the categories of lgM when considering noise (Chi-Square (12)=19.265, p=0.082) or exposure (Chi-Square (12)=18.012, p=0.115). lgM values judged by observers as representative of image quality were lower than those recorded clinically. No correlation with lgM and clinical image quality was identified in this study. Further research is recommended to include additional manufacturers and radiographic examinations. Attenuation of anode heel effect with an aluminum filter and their influence on patient dose in lumbar spine radiography J. Soares, R. Dores, P. Sousa, S.I. Rodrigues, L.P.V. Ribeiro, A.F.C.L. Abrantes, R.P.P. Almeida; Faro/PT (joana.soares.8@hotmail.com) Purpose: Study the attenuation of anode heel effect with an aluminum filter, thereby optimising the image quality, without increasing the patient dose exposure. This study was performed in a radiology department with a conventional radiology equipment. The filter construction was based on the radiographic study of the lumbar spine in a lateral position, and used the following technical parameters: 80 kV, 10 mA, 100 ms and 90.2 cm of SID. Experiments were performed to study the behaviour of anode effect along the longitudinal anodecathode axis. Measurements of dose rate using the Detetor Unfors Xi RF was carried out. This detector also allowed performing the equipment quality control. In order to standardise the variation in beam intensity of x-ray filters were used with different thicknesses of aluminum to reduce the value of the dose rate and to determine the thickness of the filter construction. After construction of the filter, The stereological approach enables the quick estimation of RV parameters with high accuracy and reproducibility from MR images. Automated computerized software for diameter and volume measurements of pulmonary metastatic disease: preliminary evaluation E. Lotan, D. Aharoni, S. Raskin, B. Boursi, R. Berger, E. Konen; Ramamt Gan/IL Purpose: Serial CT scans of metastatic tumours are vital in assessing the efficacy of cancer treatment. We evaluated the performance of a novel automated computerized software system that integrates registration, segmentation and tumour measurement into a single process to expedite RECIST measurement with the addition of volume measurement. Methods and Materials: Measurements of long and short-axis of 50 lung metastatic lesions in 18 sequential patients with metastatic renal cell carcinoma were manually obtained twice by 3 radiologists. Those measurements were compared with automated software measurements (Carestream Health, Rochester, NY). In addition, the software automatically identified the lesions' contours and volumes; the readers could accept the automated measurement or correct it manually. Intraobserver correlation was assessed by intraclass correlation coefficient (ICC), and interobserver reliability by the concordance correlation coefficient (CCC) and Bland-Altman limits of agreement. Purpose: Clinical guidelines for follow-up of pulmonary nodules depend on nodule type and therefore accurate characterisation of nodules is important. A novel computer-aided diagnosis (CAD) system to distinguish solid, part-solid and nonsolid nodules is presented and evaluated on a large data set from a lung cancer screening trial. Methods and Materials: The automated characterisation system is based on a previously published nodule segmentation algorithm. Four different parameter settings were used to extract the solid part, non-solid part and solid core of the lesion. For each segmentation, volume, mass, average density, 5 th percentile and 95 th percentile of densities inside the segmentation were used as features. A k-nearestneighbour classifier was used to classify nodules. The accuracy of the system to differentiate between solid and subsolid nodules, between solid, part-solid and non-solid nodules and between part-solid and non-solid nodules was evaluated. A data set consisting of 137 low-dose chest CT scans (16x0.75 mm, 120-140 kVp, 30 mAs) with 52 solid, 50 part-solid and 50 non-solid nodules was collected from a screening trial. The nodule type recorded in the screening database was used as the reference standard. Experiments were performed in leave-one-nodule-out cross-validation. The accuracy of CAD to differentiate between solid and subsolid nodules was 0.88. Differentiation into solid, part-solid and non-solid nodules gave an accuracy of 0.72. CAD had an accuracy of 0.71 in differentiating part-solid from non-solid nodules. Automated characterisation of pulmonary nodules shows good performance. This can aid radiologists to decide on appropriate workup in clinical practice. Author Purpose: Right ventricular (RV) volume and ejection fraction (EF) assessment is of clinical value. This procedure, based on manual delineation of the endocardial contours on MR images, is time-consuming due to ventricle's complex shape. We introduce a stereological method for estimating RV parameters from MRI data without the need for image segmentation. Methods and Materials: Twenty-two consecutive patients with coronary artery disease underwent cardiac MRI. Stereological estimations involved the automatic placement of a systematic grid of test points with random orientation over shortaxis images. All points hitting the RV were counted using the semiautomatic point selection process. The optimum point spacing of the grid was defined. The software automatically provided the RV volumes and EF. Two independent observers evaluated the measurement reproducibility. Stereological estimations were compared with those determined by manually tracing RV contours. Results: Acceptable estimations of RV parameters with a mean coefficient of error of 6.9±1.3% were obtained by counting an average of only 12 points per image. The mean time of stereological analysis was 3.7±0.4 min, whereas the intraobserver and interobserver variability was 3.2-5.2% and 4.6-7.8%, respectively. The mean differences between stereology and manual tracing for estimating the end-diastolic volume, end-systolic volume and EF were small and equal to 4.1±8.0 ml, 2.1±4.6 ml and -0.4±3.5%, respectively. The parameters obtained by the two methods were not significantly different (p> 0.05), and they were strongly correlated (r> 0.88). performed after standardised preparation. 2D-motility-acquisitions (dynamic-2D-T2-FIESTA; TR 247.07/TE 1.23/FOV500/15 mm) covering the entire small bowel were performed in free breathing over 75sec. Image analysis for the assessment of small bowel motility was performed both manually and with the software. The time consumption and reproducibility were compared using coefficient of variance and paired Student`s t-test. Results: 25 single regions of interest were analysed two times by hand and two times using Motasso with a dedicated displacement provider. Mean small bowel contraction frequency was 5.25 contractions per minute (SD+-2.74) for manual and 4.86 (SD+-2.48) for Motasso analyses; the mean luminal diameter was 17.88 mm (manual, SD+-9.31) and 18.00 mm (Motasso, SD+-9.13), respectively. The variability of repetitive measurements (coefficient of variation) was 9.77% (SD+-11.08) for manual and significantly lower (p < 0.01) for Motasso-assisted measurements (3.90%, SD+-5.69). The mean duration needed for a single small-bowel motility assessment was 17.48 min for manual (SD+-1.75 min, range 14-22 min) and high significant lower (p < 0.001) for Motasso-assisted measurements (4.52 min, SD+-1.58, range 2-8 min). The use of Motasso proves highly reliable and fast measurements of small bowel motility in free breathing MRI. Reproducibility was significantly higher for Motasso-assisted than for manual measurements, while the time needed for the single measurement could be tremendously reduced using Motasso. Purpose: Plaque treatments carry considerable risk, and hence, adjunct techniques are necessary to help doctors in making a confident decision about the necessity of such procedures for a patient. Mostly, symptomatic patients face a greater risk of cardiovascular diseases, and hence, classification of the plaque into symptomatic and asymptomatic is necessary. Therefore, we have developed a non-invasive computer-aided diagnostic technique for the same. Methods and Materials: Carotid artery images were acquired using multi-detector row CT angiography (MDCTA). The region of interest (ROI) was segmented manually from the images, and the ROIs were used to extract texture-based and discrete wavelet transform-based features. Significant features were used to train and test support vector machine (SVM) classifiers of various kernel configurations. The SVM classifier with a polynomial kernel of order 3 presented the highest accuracy of 90%, sensitivity of 95.6%, and specificity of 84.4%. We formulated a RiskScore, which is a combination of all the features, in order to monitor the variations in features, and also to more objectively classify the two classes. Conclusion: A technique that uses the CT images to identify symptomatic and asymptomatic plaques would add more value to this modality in the area of atherosclerosis management. We have proposed and demonstrated the efficiency of one such technique in this work. The classification accuracy is high, and the technique is non-invasive, fast, highly objective, cost-effective and user-friendly. Therefore, it can serve as a valuable adjunct tool that can be used by clinicians in deciding treatment options for patients. Automated labelling framework applied on full and partial spine CT scans D. Major, J. Hladuvka, F. Schulze, K. Bühler; Vienna/AT (david.major@vrvis.at) Purpose: The spine is often a frame of reference for diagnosis. For this purpose its parts have to be labelled in upper body CT scans which is a time-consuming task. An automated framework is introduced for detecting intervertebral disk and vertebra centre points and its labels in CT data containing the spine fully or partly considering clinical resource constraints. The framework uses a machine learning-based classification approach for detecting spinal canal centre point candidates as a first step. Intervertebral disk-, rib-and sacrum centre point candidates are extracted next to the spinal canal by the same classification approach. Intevertebral disk centre point labelling is started relative to either ribs or sacrum depending on detection certainty. The labelling run is done iteratively along the spine by obtaining best matches of trained local appearance models to detected three intervertebral disk and spinal canal centre point candidate clusters. Vertebra centres/labels are derived from the intervertebral disk ones. The framework has been trained on 16 and tested on 36 solutions. Accordingly, dedicated software was developed. We evaluated its clinical performance in a series of brain tumours imaged with state-of-the-art 3 T-MRI. Methods and Materials: Seventeen enhancing brain tumours were investigated (Magnetom Trio/3 T; dynamic T1-weighted-sequence/TWIST: temporal-resolution: 1.77s, in-plane-resolution: 1.2*1.1*1.1 mm 3 , 10 ml Dotarem@2 ml/s; anatomicsequence/MPRAGE: in-plane-resolution: 1.0 mm 3 ). Post-processing was performed to test a dedicated commercially available CAD-tool. Amongst other pre-processing features it implements [1] Elastic 3D-Motion-correction (dynamic-contrastenhanced scans), [2] co-registration of DCE-and anatomic-scans (3D and 4D), [3] identification of regions-of-interest (3D-ROI), [4] identification of appropriate arterial-input-function (AIF). Output data include quantitative pharmacokineticparameters (two-compartment Tofts-model: k trans , k ep , Ve, etc). and fitted/unfitted enhancement-curves ([mmolGd/l]). All 4 pre-preprocessing features and the quality of fitted curve-data were evaluated by an experienced neuroradiologist and scored on confidence-scales (0=not appropriate to 10=excellent). Pharmacokineticparameters were correlated with final diagnosis (benign/malignant: ROC-analysis). Results: Motion-correction was technically successful in all cases. Co-registration in 3D (mean-score[ms]:9.4) and 4D (ms=9.3) as well as identification of the AIF (ms: 9.6) reached excellent ratings. Placement of 3D-ROIs was difficult in one lesion (score=6). Yet, in total it was performed appropriately (ms=9.0). Overall quality of fitted curve-data reached good scores (ms=9), resulting into a high diagnosticaccuracy for the differentiation of benign vs. malignant tumors (AUC=89% [k ep ]). The software showed an excellent clinical performance. This should help to further promote quantitative pharmacokinetic-analyses and might broaden its application in clinical practice in the future. Rapid semi-automated volumetry of pleural effusion in MDCT M.P.F. Botelho, F.D. Gonzalez-Guindalini, H. Chalian, V. Yaghmai; Purpose: To evaluate precision and reproducibility of volumetric semi-automated quantification of pleural effusions in MDCT. This study was IRB approved. We evaluated 29 consecutive pleural effusions in 20 adult patients undergoing contrast-enhanced MDCT of the chest. Two independent blinded readers used a semi-automated segmentation software for estimation of volume and recorded quantification time. Manual volumetry was obtained as the reference. We evaluated the volumetry for precision, time for assessment and inter-rater agreement, as well as percentage of over-and under-segmentation. Statistical analysis encompassed paired t-test, Bland-Altman plot and Lin's concordance correlation coefficient. The mean semi-automated and manual volumes were 1040.3 mL (SD 964.6 mL) and 1033.1 mL (SD 979.0 mL), respectively (P=0.379). Semi-automated volumetry showed significant inter-rater agreement, with Bland-Altman precision of 8.2% (upper and lower limits of 18.5% and -13.7%, respectively). The mean semi-automated volumetry was accurate when compared to manual volumetry, with Bland-Altman precision of 5.0% (upper and lower limits of 12.1% and -7.7%, respectively), and Lin's concordance correlation coefficient (ρc) = 0.998. There was a mean of 2.3% over-segmentation using the semi-automated software. The average user time for semi-automated volumetry was 105.3 sec/case, whereas those for manual volumetry were 336 sec/case (P < 0.001). Conclusion: Rapid and accurate semi-automated volumetry of pleural effusions in MDCT is feasible and reproducible. Purpose: To present a paradigm shift in computer-assisted image interpretation and to assess its application in CT colonography. A novel segmentation-free scheme has been developed with the hypothesis that accurate colon segmentation is neither necessary nor an end clinical objective for delivering efficient support such as colon centreline, electronic colon cleansing (ECC) and computer-aided detection of lesions (CAD). Methods and Materials: Thick regions are expanded until they encompass statistically significant representations of the colon wall and its surroundings (Air, Tag, Soft/Hard tissue). From these regions, a coarse colon centreline is inferred through topological analysis guided by anatomic constraints; ECC is obtained by determining a transposing function depicting the distribution of voxels in a given Air-region, and applying said function to Tag-regions depicting statistically similar colon wall surroundings; unlike surface shape analysis, a CAD identifies local hyper-density concentrations from implicit surfaces flux, at a given depth related to the targeted lesion size. The complete schemes were retrospectively tested on 111 and 135 patients datasets for {centreline; electronic cleansing} and CAD, respectively. Results: Colon centreline extraction was accurate in 85% of combined cathartic and tagged datasets. CAD performance was similar to that in the literature, specifically a sensitivity of 80% [70] [71] [72] [73] [74] [75] [76] [77] [78] [79] [80] [81] [82] [83] [84] [85] for lesions at least 7 mm featuring a false-positive rate less than 5 per-patient. The presented novel paradigm in computer-assisted image interpretation prevents traditional limitations arising from "accurately segmenting" a specific organ for further processing. To our best knowledge, this is the first attempt to design and validate such a paradigm shift in CT colonography. Purpose: The role of mesorectal vasculature in rectal cancer is poorly understood. Aim of our study was to determine impact of tumour growth as well as neoadjuvant chemoradiotherapy on mesorectal vasculature. Methods and Materials: Ten patients with locally advanced rectal cancer underwent (re)staging MRI. Dynamic contrast-enhanced MRI with blood pool contrast agent (gadofosveset) was performed. Maximal intensity projections (MIPs) were used to assess macrovascular structure. Number, diameter and length of vascular branches were determined in mesorectum surrounding tumour and normal rectal wall. Same parameters were used to compare pre-and post-chemoradiotherapy MIPs. The mesorectal microvascular function was studied using relative enhancement-time curves, and expressed as area under the initial 2 minutes of the enhancement curve (AUC). Results: A significantly higher number of vessel branches was found in tumourneighbouring mesorectum compared to mesorectum around normal rectal wall (p=0.001). Furthermore, vessel diameter in tumour surroundings was 0.2 mm larger (p=0.025). The average AUC in tumour-neighbouring mesorectum was also higher (6.35 and 0.58, respectively (p=0.01)). Comparison of pre-and post-CRT MIPs revealed 40% lower vessel branching after CRT (p=0.002). Moreover, the vascular diameter of 1.7 ± 0.2 mm at the primary staging was significantly decreased to 1.3 ± 0.2 mm after CRT (p=0.007). In contrast, CRT resulted in significantly increased AUC values. Conclusion: There is a significantly enhanced vascular structure and function in the tumour-surrounding mesorectum, which may have an important prognostic value for rectal cancer patients. Furthermore, chemoradiotherapy induces remodelling of the mesorectal vasculature. Value of 3D FSE Cube sequence at 3 T MRI in preoperative local staging of rectal cancer R. Scandiffio, P. Vagli, P. Bemi, A. Mantarro, L. Faggioni, R. Balestri, P. Buccianti, E. Neri, C. Bartolozzi; Pisa/IT (rossellascandiffio@libero.it) Purpose: To compare a standard T2w imaging, based on 2D acquisitions, with 3D FSE Cube sequence in the local staging of rectal cancer at 3 T MRI. Methods and Materials: 32 patients with rectal cancer were prospectively evaluated at 3 T MRI before and after neoadjuvant chemotherapy. Sagittal, coronal, axial and oblique 2D T2w FSE images and an additional 3D T2 FSE Cube sequence were obtained. Each 3D dataset was processed with multiplanar and curved planar reconstructions along the rectal centreline. Two experienced radiologists, using, respectively, 2D or 3D sequences evaluated T and N parameters, with specific attention to measurement of the distance lesion-puborectal muscle and mesorectal fascia, and lesion extension. All T and N parameters were evaluated independently and grouped for statistical analysis. Linear Cohen k values were calculated to quantify agreement between MRI and histopathological data. Image quality was evaluated using a linear qualitative scale. Results: Global sensitivities for T parameters were 67% and 62% for 2D and 3D images, while N category lesion accuracy values were 70% and 68%, respectively. Accuracy in measuring the distance from pubo-rectal muscle to lesion border was 60% and 98% for 2D and 3D, respectively. Image quality was considered very good on 2D images, and good on 3D images. Conclusion: No significant differences between 2D and 3D images were observed for T and N staging. T2w FSE Cube demonstrated higher accuracy than 2D in determining the distance between lesion and pubo-rectal muscle, which represents a key factor in planning surgical resection. Purpose: Spatial vascular heterogeneity decreases from periphery towards tumour core in solid tumours and is related to cancer viability. This pattern is not present in rectal tumours. The aim of this study was to determine whether rectal tumour spread into layers of rectum, affects tumour vascular function compared to that of normal rectal wall. Tumours were segmented into luminal, mural and extramural regions. Normal tissue counterparts were defined (mucosa, muscularis propria and mesorectal fat). Initial slope (slopei) and area under the first 120s of enhancement curve (AUC120) were determined from relative signal enhancement-time curves. Pixel parameter values and mean parameter values were compared per patient and for entire patient group. The correlation between kinetic parameters of tumour segments and of corresponding normal tissues was determined. Results: For each patient, both the slopei and AUC120 were significantly higher for luminal tumour pixels compared to mural and extramural tumour pixels (p < 0.05). Mural pixel parameter values were significantly higher than the extramural pixels (p < 0.05). For the patient group the mean AUC120 for the luminal, mural and extramural tumour region was 240±46, 178±20 and 129±18, respectively. There was a strong and significant correlation between the parameters of tumour segments and those of corresponding normal tissues (Pearson's correlation coef-ficient=0.84, p=0.0001). Purpose: Patients with complete response (CR) after CRT might be considered for less aggressive treatment like a wait-and-see strategy. Few studies investigated the value of DWI-MRI for predicting CR after CRT, but none included lymph nodes in the analysis (ypT0N0). The aim of the present study was to retrospectively determine the additional value of DWI-MRI to conventional (T2-weighted) MRI for predicting CR after CRT. Methods and Materials: Eighty locally advanced rectal cancer patients underwent CRT followed by restaging MRI and operation. MRI consisted of conventional sequences and DWI. Two readers with different levels of experience independently scored conventional images for CR and, in a second reading, combined conventional and DWI-MRI images. A 5-point confidence level score was used to generate ROC curves. Differences in performance were calculated by comparing areas under the ROC curves (AUC). Interobserver agreement, sensitivity, specificity and positive predictive values (PPV) were calculated. Histology served as reference standard. Results: Ten of 80 patients (13%) had a pathologic complete response (ypT0N0). Comparison of the ROC curves showed significant improvement of the AUC only for the experienced reader 1 from 0.77 to 0.88 (p=0.009). Sensitivity improved from 20-30% to 40-70%. Specificity and PPV improved only for reader 1 from 87 to 93%, resp., 25 to 58%. Interobserver agreement improved from 0.14 to 0.27. Conclusion: Adding DWI to conventional MRI improves diagnostic performance of experienced readers and increases interobserver agreement for identification of CR. Sensitivity and PPV remain low, with a considerable risk of over-and undertreatment. Purpose: Transanal endoscopic microsurgery (TEM) is a minimal invasive technique for local resection of T1 and selected T2 tumours and is also an emerging option for good-responders after chemoradiation. In most centres follow-up includes regular MRI. This study aimed to describe the MR morphology of the rectal wall during follow-up in patients that received TEM. Methods and Materials: Forty-nine patients underwent a post-TEM MRI in our centre. For 21 patients only one post-operative MRI was available. For 28 patients > 1 MRIs were available. The MR morphology of the TEM-site was studied on the consecutive MR examinations. 32 patients were primary treated with TEM, 17 patients underwent chemoradiation followed by TEM. Results: We identified three morphological patterns: (1) rectal wall thickening with or without fibrosis, (2) a notch at the TEM-location, and (3) irregular delineation of the rectal wall. Multiple patterns could occur within one patient. 32 patients (65%) had rectal wall thickening, 17 patients (35%) a notch, and 28 patients (57%) irregular delineation of the rectal wall. In addition to these patterns, oedema (due to chemoradiation) persisted in post-chemoradiation TEM-patients. Ten patients had dehiscence after TEM post-chemoradiation (n=58%). Six luminal recurrences occurred; 3 had rectal wall thickening, 3 a notch, and 5 an irregular rectal wall. Sinogram-affirmed iterative reconstructed simulated ECG-gated ultra high pitch CT pulmonary angiography in the acute setting: effect on dose and image quality S.J. Co 1 , S. Nicolaou 1 , J. Mayo 1 , T. Liang 1 , D. Hou 1 , K. Krzymyk 2 ; 1 Vancouver, BC/CA, 2 Topanga, CA/US (co.steve@gmail.com) Purpose: To evaluate the effect of a simulated ECG-gated computed tomographic pulmonary angiography (CTPA) at 100 kV on image quality and radiation dose. Retrospective study includes 100 patients referred for CTPA with pitch 3.2. 50 patients were scanned with a standard 100 kV protocol and 50 patients were scanned with a simulated ECG-gated 100 kV protocol that introduces a specialized cardiac bowtie filter. All other scanning parameters were kept constant. Images were reconstructed with filtered back projection and iterative reconstruction (SAFIRE, Siemens). Central pulmonary vessel attenuation and background noise were quantitatively measured and signal-to-noise (SNR) and contrast-to-noise (CNR) were calculated. Two radiologists performed qualitative assessment grading visualisation of the pulmonary vasculature and noise level (Likert scale). Volume CT dose index and dose length product were recorded and effective dose was calculated. Purpose: To evaluate the impact of iterative reconstructions on the diagnosis of acute PE on low-dose CT angiograms. Methods and Materials: 53 patients were prospectively enrolled in a study designed to compare low-dose and full-dose images simultaneously available from the same dataset. The examinations were acquired with (a) both tubes set at similar energy (120 kVp) and (b) the total reference mAs (i.e., 110 mAs) split up in a way that 40% was applied to tube A while 60% was applied to tube B. Three series of images were generated: (a) full-dose images (generated from both tubes), reconstructed with FBP (group 1), used as the standard of reference, (b) low-dose images (generated from tube A; 60% dose reduction) reconstructed with FBP (group 2), then with an iterative reconstruction algorithm (SAFIRE) (group 3). Results: All 81 patients showed significant decrease of QS (mean 17.4 to 9.8, p <.001), RLR and AOPA between initial and F/U CT-PA. In 10/81 patients complete PE lysis was found. There was good correlation between reduction of QS and regression of RLR (r=-.506; p <.001) and AOPA (r=-.458; p <.001), respectively. RLR and AOPA changes (r=.330; p=.003) correlated poorly. Patients with initial QS > 20 showed higher reduction of QS at F/U, but no significant difference was found concerning the reduction of RLR between patients with initial QS > 20 and ²20 (p=.921). The time interval between initial and F/U CT-PA differed between patients with and without complete lysis (3.5 vs. 2.14 weeks, p=.016). Conclusion: Clot resolution is associated with improvements of RLR and AOPA, but the time to complete resolution is variable and not predictable. RLV and AOPA are independent markers of right heart burden in patients with PE, but they correlate poorly with each other. Clinical significance of high density thrombi on non-enhanced CT scan in patients with pulmonary thromboembolism K.S. Beck, B. Lee, H. Kim, D. Han; Seoul/ KR (sallahbar@gmail.com) Purpose: To evaluate the incidence and significance of occasionally detected high density thrombi of pulmonary embolism (PE) on non-enhanced chest CT scans. We retrospectively evaluated the non-enhanced and enhanced CT findings of 76 patients with pulmonary embolism, and the incidence of high density thrombi was calculated. Then in both iso-density thrombi (group 1) and high-density thrombi (group 2) groups, embolic burden score, ventricular septal bowing, and diameter of right ventricle (RV) and left ventricle (LV) were evaluated and compared using independent sample T tests. Purpose: To investigate the general applicability of a 70 kV protocol for routine CT pulmonary angiography (CTPA) in unselected patients. Methods and Materials: Thirteen patients suspected of having pulmonary embolism underwent CTPA with a novel 70 kV protocol (208 mAs, pitch 1.2) on a 64-slice CT device. Ten patients who were investigated with the standard protocol (100 kV, 120 mAs, pitch 1.2) served as the control group. Images were reconstructed with sinogram affirmed iterative reconstruction with medium regulation strength in both groups. 75 ml of contrast material (350 mgI/ml) was injected at 4 ml/s. CTDIvol, DLP, signal intensity in the pulmonary trunk and segmental arteries and corresponding SNR values were compared. Images were assessed for diagnostic quality and artefacts. Results: Chest diameter was not significantly (p> 0.05) different between the groups. CTDIvol (2.3 vs. 6.6 mGy) and DLP (71 vs. 193 mGycm) were by 65% and 63% lower at 70 kV (p < 0.05); iodine attenuation was significantly higher (e.g. segmental arteries 554 vs. 313 HU), but so was image noise, resulting in no significant differences in SNR. Photon starvation artefacts from dense contrast material in the venous system and high image noise in bigger patients were the main drawbacks at 70 kV. Conclusion: 70 kV CTPA seems feasible in clinical routine and results in a dose reduction of more than 60% compared to a 100 kV protocol at equal SNR; however, patient selection is advisable. Artefacts from inflowing contrast material will require dedicated injection protocols or the use of low-iodine contrast material. Purpose: Pulmonary hypertension (PH) is a disease characterised by an elevated pulmonary arterial pressure (PAP) and is diagnosed invasively via right heart catheterization (RHC). We explored whether timing measures from dynamic contrast-enhanced computed tomography (CT) can be used as a non-invasive method to determine PH. Methods and Materials: 20 patients (15 with and 5 without PH) were examined with a novel dynamic contrast-enhanced CT sequence following their diagnostic or follow-up RHC. X-ray attenuation over time curves were recorded for several regions of interest (ROIs) in the main pulmonary artery and in the ascending aorta and subsequently fitted with a spline fit. Time differences between the contrastmaterial bolus peaks were measured. Distances between the ROIs were measured in a simultaneously acquired thorax CT to calculate the bolus propagation speeds. We compared our results to haemodynamic parameters acquired during RHC. Results: Time differences between peaks showed good correlation (Spearman correlation coefficients ³ 0.65) with mean PAP, pulmonary vascular resistance and gas exchange parameters. Discrimination between patients with and without PH was achieved by evaluating time differences (sensitivity/specificity 100%/80%, 95% confidence intervals: 72-100% and 28-99%, respectively) and bolus speeds (sensitivity/specificity 100%, 95% confidence intervals: 72-100% and 48-100%, respectively). ) . Lesions located in the vertebral body were excluded, while lesions in proximity to joints or neurovascular bundles were included. Treatment success was determined at clinical and imaging follow-up at 1, 3, and 6 months post-treatment. A visual Analog Pain Score (VAS) was used to assess changes in symptoms. Results: Treatment was carried out using a variable number of sonications (mean 4±1.8) with a mean energy deposition of 866±211 J. There were no treatment-or anaesthesia-related complications. A statistically significant (p=0.001) difference was noted between the overall pre-and post-treatment mean VAS scores (8.3±1.6 and 0.6±1.5, respectively). Six of the 7 treatments were conducted on patients with typical osteoid osteoma and all were completely clinically successful. The patient with giant osteoma had pain recurrence after 2 weeks, requiring surgery. At imaging, oedema and hyperemia associated with typical osteoid osteoma gradually disappeared in all lesions. No apparent relationship between nidus vascular extinction and successful outcome was found. Conclusion: MRgFUS ablation represents an effective and totally non-invasive therapeutic option for osteoid osteoma management, without treatment-related adverse events. Purpose: Radiographic damage was recently identified as a feature of poor prognosis in polyarticular juvenile idiopathic arthritis (pJIA). However, most radiographic studies did not differentiate pJIA from other subtypes of JIA and little is known in pJIA persisting into adulthood. We set out, therefore, to describe radiological peripheral involvement in young adults with pJIA as compared to rheumatoid arthritis (RA) patients. Methods and Materials: All consecutive pJIA patients followed in a transition program were included. Age, sex, disease duration, and treatment information were collected. Laboratory tests and standard radiographs of the hands and wrists, feet and hips were then analysed by two independent radiologists blinded to the diagnosis. A RA control group (< 55years), matched for sex and disease duration, was recruited. Düsseldorf/DE (Rotem.Lanzman@med.uni-duesseldorf.de) Purpose: The purpose of our study was to investigate changes in kidney perfusion following renal denervation using arterial spin labelling (ASL) MRI at 1.5 T. Methods and Materials: 7 patients (mean age 58 ± 13 years) undergoing interventional renal denervation were included in this study. In each patient, between 6 and 8 ablations were performed per renal artery. ASL MRI was performed at 1.5 T using a single-slice FAIR TrueFisp sequence in the coronal plane (30 averages of label and control pairs, inversion time 1200 ms, slice thickness 8 mm, matrix 128x128) prior to and within 24 hours following renal denervation. Patients refrained from fluid intake for at least 2 hours prior to the examination. Following post-processing, ROIs were drawn by a single reviewer on ASL parameter maps for quantification of cortical perfusion. Both kidneys of each patient were used for statistical analysis. Results: Image acquisition was completed successfully in all patients and perfusion was determined for 14 kidneys in 7 patients. In 6 patients, ASL perfusion increased by at least 10% following denervation, while in one patient ASL perfusion decreased following intervention. Mean ASL perfusion following renal denervation (245.8 ± 43.3 ml/100 g/min) was significantly higher than prior to denervation ( Purpose: To evaluate trochlear morphology as a potential risk factor for patellofemoral osteoarthritis, determined by morphological and quantitative measurements of cartilage degeneration using 3 T magnetic resonance imaging (MRI) of the knee. Methods and Materials: MR images of right knees of 304 randomly selected subjects, aged 45-60 years, from the osteoarthritis initiative (OAI) progression cohort were screened for trochlear dysplasia, defined by a pathological trochlear depth. Out of 304 subjects, n=85 demonstrated a shallow trochlea (depth ²3 mm; 28%). In these, and also in a random sample of controls with normal trochlear depth (n=50), we calculated the facetal ratio and assessed knee structural abnormalities using a modified Whole-Organ-MR-Imaging Score (WORMS). Cartilage segmentation was also performed and T2 relaxation times and patellar cartilage volume were determined. ANOVA and multivariate regression models were used for statistical analysis of the association of MRI structural measures and trochlear morphology. Results: Knees with a shallow trochlea showed higher patellofemoral degeneration (WORMS mean ± standard deviation, 11.2±4.6 versus 5.7±4.2; multivariate regression, P < 0.001) and lower patellar cartilage volume than controls (900±664 mm3 versus 1671±671 mm3, P < 0.001). Knees with a pathological facetal ratio showed increased patellofemoral WORMS scores (8.3±4.6 versus 2.3±6.3, P < 0.001). T2 values at the patella were significantly lower in the dysplasia group. However, significance was lost after adjustment for cartilage volume (multivariate regression, P=0.673). Conclusion: Trochlear dysplasia, defined by a shallow trochlea, is associated with higher WORMS scores and lower cartilage volume, indicating more advanced osteoarthritis at the patellofemoral joint. Reliability of tomosynthesis for semiquantitative assessment of knee osteoarthritis features by radiologists with different levels of expertise Purpose: To describe early x-ray findings in the hands and evaluate progression of destruction after five years correlated to clinical parameters in early psoriatic arthritis (PsA). In 31 men and 46 women with PsA fulfilling the CASPAR criteria hand x-rays were available from the 5-year follow-up and either inclusion or the 2-year visit. X-rays were scored by the Wassenberg scoring system. Results: Median symptom duration at inclusion was 12 months. 58% had polyarticular and 38% mono/oligoarticular PsA. At the first evaluation 60% had Wassenberg score zero. At the 5-year visit median score was 2. In 34 patients (44%) the score was still 0, in 28 between 1 and 5, in 5 between 6 and 10, in 6 between 11 and 15, and 1 patient each had a score of 19, 22, 39, and 42. At baseline women had significantly higher disease activity than men, but similar x-ray score. At 5 years men had improved considerably in function and disease activity score, but had greater x-ray progression (58% vs 28%, p=0.009). Male gender was a significant predictor of x-ray progression. Longer symptom duration at entry predicted x-ray progression (p=0.038) and prevented minimal disease activity (p < 0.001). Conclusion: After 5 years of PsA, most patients still have no or very little hand joint destruction. Symptom duration at inclusion and male gender were the main predictors of x-ray progression, preserved function at baseline was protective. Despite worse clinical outcome with higher disease activity scores, women had less x-ray progression than men. Purpose: Cortical thickness mapping is a technique that uses clinical computed tomography (CT) imaging to plot the distribution of cortical bone thickness in 3D. Given our understanding of their relationships with bone mineral density, we performed a study to investigate the effects of age, weight, and osteophytes on cortical bone distribution in the proximal femur. We analysed CT imaging data from a cohort of 230 women aged 66±17 years, selecting one hip from each randomly according to side. A DICOM analysis tool (Stradwin) was used to contour each hip semi-automatically and create a 3D surface mapped with individual cortical thickness values. Statistical parametric mapping was then performed to investigate model effects of age, weight and osteophytes on cortical thickness. Results: Cortical thickness was generally thinner with advancing age, but was preserved in characteristic load-bearing regions at the medial femoral neck and lateral subtrochanteric cortex. Greater weight was also associated with significantly thicker cortex per kilogram at these same sites. Including osteophytes in the model showed that increasing severity was detected as increasingly thick cortical bone around the articular margin at the femoral head-neck junction. Conclusion: These results demonstrate, for the first time, the effects of age, weight and osteophytes on cortical bone thickness in the proximal femur. It will be essential for future analysis of bone in this region to take these effects into account. Conclusion: Raw-data-based iterative reconstruction significantly improved image quality in very-low-dose prospectively ECG-triggered coronary DSCT angiography when compared to standard reconstruction using FBP. Along with substantial reduction of radiation exposure, iterative reconstruction also shows a trend towards higher accuracy in coronary stenosis detection compared to FBP. Methods and Materials: 12 patients underwent evaluation of the RV function on 1.5 T employing a 32-element coil. Acquisition was performed using a real-time radial SSFP sequence (16 projections) in a multislice breath-hold and free-breathing setting with a spatial resolution of 2x2 mm 2 (matrix 128; slice 6 mm) and a temporal resolution of 46 ms (TR 2.9 ms). Through-time radial GRAPPA reconstruction was performed off-line (MATLAB) incorporating fully sampled (128 projections) calibration data acquired prior to the undersampled datasets. Segmented Cartesian cine SSFP was acquired at identical slice positions in multiple consecutive breath-holds with a spatial resolution of 1.3-1.5x1.3-1.5 mm, 6 mm slices and 35 ms temporal resolution (TR 3 ms). Free-breathing and breath-hold real-time datasets were evaluated for RV size and function and compared with segmented cine SSFP. This HIPAA-compliant study was approved by the Institutional Review Board and patients gave informed consent. 20 patients underwent delayed phase cardiac CT on a second-generation DECT scanner. Late iodine enhancement data were compared with late gadolinium enhancement images from 3 T cardiac MRI. DECT greyscale images were reconstructed as 100 kV, 140 kV and weighted-average (WA; linear blending) images from low and high kV data incorporating 80%, 60% or 30% of 100 kV data. In addition, a colour-coded map of myocardial iodine distribution was calculated from DECT data. Two independent blinded radiologists reviewed all images for late enhancement areas in standard cardiac views and rated subjective image quality. Results: DECT data from 100 kV, WA-80% and WA-60% showed identical results for the correct identification of myocardial scarring (89% sensitivity, 98% specificity and 96% accuracy). However, WA-60% received the best subjective image quality rating and average measured infarct size correlated best with MRI. Colour-coded iodine distribution maps were prone to artefacts (52% sensitivity, 88% specificity, 81% accuracy), overestimating quantity of scars while underestimating lesion size by 55% compared to MRI. Conclusion: Linear blending of delayed phase cardiac DECT data improves image quality for the detection of myocardial scar tissue compared to MRI. Colour-coded myocardial iodine distribution maps were prone to artefacts and showed inferior diagnostic performance. Influence of iterative reconstruction on coronary calcium score in cardiac computed tomography K. Jaspers 1 , J.A.C. Van Osch 2 , J.M. Groen 1 , M.J.W. Greuter 1 ; 1 Groningen/NL, 2 Zwolle/NL (m.j.w.greuter@umcg.nl) Purpose: To investigate the relation between the percentage of iterative reconstruction (IR) and coronary calcium score in cardiac computed tomography (CT). A phantom containing 100 cylindrical calcifications with varying size and density was inserted into a thorax phantom (QRM Thorax, QRM, Germany) with artificial lungs and spine. The phantom was scanned with a clinical acquisition protocol on a 64-slice CT (Lightspeed VCT XT, GE). Each scan was repeated five times. The images were reconstructed with filtered backprojection (FBP) and increasing percentages of IR of 20-100%. The amount of calcium was determined as an Agatston score. The influence of percentage IR on both total Agatston score (TAS) of the phantom as well as the individual calcium score (IAS) for each calcification was investigated. Purpose: To demonstrate that diffusion-weighted imaging (DWI) is able to pick up intracranial recurrences of medulloblastoma (MB) with higher sensitivity than contrast-enhanced (CE) series. Methods and Materials: All MRI examinations of 22 children with histologically proven MB were retrospectively evaluated. Routine follow-up examinations were performed initially 3 months after operation and thereafter, every 6 months for the next 2 years. Then, controls were done yearly. Concomitant cranial and spinal MRI included T1, T2, and FLAIR in the axial plane, followed by T1 after gadolinium (Gd) in 3 orthogonal planes for the brain. Additional DWI was performed. Subsequent spinal imaging included sagittal T1-en T2-weighted images. Results: Eleven recurrences were observed in 10 patients. In 5 patients recurrent disease was observed at the resection site in 2 of which subarachnoid spread was also observed, with recurrence in loco only in 3 patients. Five patients had recurrent disease away from the resection cavity, 2 of them in the frontal areas and 4 intraventricular recurrences at the supratentorial level. In 2 patients CE-series scored better than DWI; in 3 patients results on DWI and CE-series were equivocal. In 5 patients, recurrences were better demonstrated on DWI; some of them were only observed in retrospect. The results of our retrospective study demonstrate that DWI is a powerful technique allowing for early diagnosis of recurrent disease in MB patients. DWI especially demonstrates non-enhancing metastatic lesions earlier than CElesions. DWI should therefore be included in surveillance imaging protocols of MB patients, especially in the group of high-risk patients. Radiation-induced telangiectasia in the long-term survivors of intracranial germ cell tumours: whole-ventricle vs whole-brain radiation L. Li, S. Mugikura, T. Murata, T. Kumabe, K. Jingu, T. Fujii, E. Mori, S. Takahashi; Sendai/JP (liliyanzhen05@gmail.com) Purpose: Telangiectasia on MR images were reported to be seen in patients who received intracranial radiation. To determine the relationship between the radiation field/dose and the prevalence of telangiectasia on MR images, we compared whole-ventricle alone (WV) and whole-ventricle plus whole-brain (WB) radiation groups in the long term survivors (more than 10 years) of intracranial germ cell tumours (GCT). We compared the number of telangiectasia on T2*weighted MR images (T2*WI) between WV (n=12) and WB (n=11) groups. Total dose of radiation between two groups was not significantly different (54. Evaluation of diffusivity in pituitary adenoma in the Sella Turcica with 3D turbo field echo with diffusion-sensitized driven-equilibrium preparation: initial experience A. Hiwatashi 1 , T. Yoshiura 1 , O. Togao 1 , K. Yamashita 1 , K. Kikuchi 1 , H. Honda 1 , M. Obara 2 ; 1 Fukuoka/JP, 2 Tokyo/JP Purpose: To evaluate the feasibility of 3D turbo field echo (TFE) with diffusionsensitized driven-equilibrium (DSDE) preparation, which is a novel non-EPI technique for diffusion-weighted imaging, for pituitary adenoma in sella turcica. Methods and Materials: This prospective study included thirteen patients (9 females and 4 males, age 19-82 years) with pituitary adenomas were imaged with 3D TFE with DSDE preparation. Among them four were prolactin-producing (PRL), three were growth hormone-producing (GH) and six were non-functioning tumours (NON). Motion probing gradients were conducted at one direction (A-P) with b values of 0 and 500 s/mm 2 . The imaging voxel size was 1.5x1.5x1.5 mm 3 . The apparent diffusion coefficients (ADCs) were measured in the pituitary adenoma and the normal pituitary gland. Results: In each patient, a pituitary adenoma was clearly visualised on 3D TFE with DSDE preparation and ADC maps without obvious geometrical distortion. ADC of the pituitary adenoma ranged from 0.57 to 2.90 x10 -3 mm 2 /s (mean ± standard deviation, 1.37±0.72 x 10 -3 mm 2 /s), and was higher than that of the normal pituitary gland (1.34±0.23 x 10 -3 mm 2 /s) without statistically significant difference (P > 0.05). ADC in PRL (2.07±0.92 x 10 -3 mm 2 /s) was significantly higher than that in GH (0.86±0.31 x 10 -3 mm 2 /s) and in NON (1.17±0.32 x 10 -3 mm 2 /s) (P < 0.05). Conclusion: With its insensitivity to field inhomogeneity and high spatial resolution, 3D TFE with DSDE preparation was feasible to evaluate the diffusivity in the pituitary gland. ADC measurement using this new technique may help characterise hormone activity of pituitary adenomas. Author Disclosures: M. Obara: Employee; Makoto Obara. and 51.3 Gy in WB groups). In the WB group, axial sections of the ventricular level were considered to have received significantly higher dose of radiation (51.3 Gy, high-dose field) than the other upper and lower levels (24.0 Gy, low-dose fields). In the WB group, we compared the number of telangiectasia on T2*WI between ventricular level and the other upper and lower levels. Results: Telangiectasias were observed in 22 (96%) patients. The number of telangiectasia in the WB group was significantly higher than the WV group (average 8.5 in WB and 3.6 in WV, P = 0.019). In WB group, the number of telangiectasia was significantly higher in the ventricular level than the other upper and lower levels (P < 0.01). Conclusion: Radiation-induced telangiectasia appears to occur in at least 96% of patients who undergo cranial irradiation. Larger radiation exposure and higher radiation dose were associated with higher number of telangiectasia lesions. Preoperative classification of cerebral tumours by applying whole brain VPCT: which parameter to use in order to achieve the highest prognostic value? Results: Typical features of fibroadenomas were "lobulated shape" (OR=8.6), "sharp margin" (OR=14.0), "internal septations" (OR=17.1), "hyperintense signal in T2w" (OR=17.6) and "persistent curve-type" (OR=16.2; all: P < 0.001). Diagnostic accuracy increased significantly (P < 0.001), if features were assessed in combination. Highest values were then observed, if the following feature combinations were present: "sharp margin and persistent curve type" (OR=140.3), "plateau and internal septations" (OR=18.1). Overall accuracy of breast MRI for the differential diagnosis of fibroadenomas vs. breast cancers revealed excellent AUC (0.95, cross-validated sample). Conclusion: In breast MRI fibroadenomas show typical morphologic and dynamic characteristics. Particularly, if multiple breast MRI characteristics are assessed in combination, differential diagnosis vs. breast cancer is possible with excellent accuracy. Purpose: To compare lesion detection and characterisation by the combination of one-view breast tomosynthesis (DBT) and one-view digital mammography with two-view digital mammography (MX). The study included 250 consenting women with breast lesions classified as suspicious at mammography and/or ultrasound. A clinical performance study comparing two-view (CC, MLO) mammography, and the combination of DBT in MLO view and MX in CC-view (DBT+MXCC) was conducted with six breast radiologists. Data were analysed per-lesion, using lesion localisation fraction -LLF (the percentage of lesions correctly localised). Lesion detection was determined by calculating the total number of lesions rated above BI-RADS 1. Lesion characterisation was evaluated by counting malignant lesions rated above BI-RADS 3 and benign lesions scored BI-RADS 2 or 3. Lesion detection and characterisation for all lesions, and stratified for malignant and benign lesions, were compared between DBT+MXCC and MX using analysis of variance (ANOVA). P-values < 0.05 were considered statistically significant. The non-inferiority margin was set at 5%. Results: Overall, DBT+MXCC was superior to MX alone in terms of number of lesions correctly detected and characterised (LLF difference: +6.85%, -95% CI: +4.02%; p-value = 0.0007). DBT+MXCC superiority was confirmed for benign lesions (LLF difference: +7.93%, -95% CI: +5.71%; p-value < 0.0001), while noninferiority was achieved for malignant lesions (LLF difference: +3.03%, -95% CI: -4.59%; p-value < 0.369). Purpose: To estimate the inter-reader reproducibility of DBT added to 2D-DM in comparison to that of 2D-DM alone. A series of 65 breasts (65 women, aged 58±9 years) underwent DBT (Giotto, IMS, Italy) as an adjunct to 2D-DM. After an agreement on how to report 2D-DM and DBT, 3 independent readers (R1, R2, R3) with > 6 years of experience in 2D-DM and > 1 year of experience in DBT evaluated all studies. Each reader evaluated the breast density and assigned a BI-RADS score using only 2D-DM. After 30 days, they repeated the evaluation adding DBT to 2D-DM. The inter-reader reproducibility was estimated using the quadratically weighted Cohen's kappa. The breast density reported at 2D-DM by the most experienced reader was: 75% in 1 (1%). Considering the B1, B2, B3, B4, and B5 BI-RADS scores, the same reader assigned the followings: 25, 0, 10, 20, and 10 using 2D-DM; 31, 1, 7, 13, and 13 using 2D-DM plus DBT. For each pair of readers, 2D-DM plus DBT resulted in a higher inter-reader reproducibility than that of 2D-DM alone: kappa value for 2D-DM ranged from 0.418 to 0.566 while that for 2D-DM plus DBT ranged from 0.656 to 0.758. Purpose: Based on a novel approach, digital breast tomosynthesis (DBT) may simultaneously acquire 2D and 3D images of the breast. Variable dose geometry is used to give a sufficient dose in the central projection for that image to be a 2D mammogram (2D-CP). We investigated whether 2D central projection (2D-CP) obtained with DBT is equivalent to digital mammography (DM) in terms of image quality. We retrospectively evaluated 45 asymptomatic patients who underwent DM and DBT with 2D-CP for screening. Two experienced radiologists in consensus reviewed the DM and 2D-CP images in separate sessions. Readers were asked to subjectively score image quality on a 1-5 scale in terms of a) artefacts (1=absent to 5=significant artefacts), b) noise (1=absent to 5=very high noise) and c) fibro-glandular-breast-tissue-to-fat-contrast (1=poor to 5=excellent). The comparison between 2D-CP and DM scores was performed with a Wilcoxon signed-rank-test on a per-breast basis. Results: There was no significant difference between DM and 2D-CP in terms of artefacts, with median scores of 2.0 for both techniques (p> 0.05). A significant difference (p < 0.05) was found between DM and 2D-CP concerning noise and contrast (median were 2 vs 4 and 5 vs 4, respectively). Conclusion: Although DM is superior to 2D-CP in terms of image noise and contrast, both techniques showed a reduced incidence of artefacts. Clinical studies should be performed to assess whether this qualitative difference has clinical relevance. The role of additional ultrasound and tomosynthesis after normal digital mammography: comparison between both techniques P. Slon, J. Etxano, I. Purpose: To increase the diagnostic accuracy of MRI in the detection and local staging of bladder tumours by using Fluid-attenuated Inversion Recovery (FLAIR) sequences. Methods and Materials: 32 patients with bladder tumours detected by US underwent MRI using 1.5 T superconductive magnet. We performed TSE T1-weighted and T2-weighted and FLAIR sequences on axial scans. The contrast to lesion ratio was always evaluated. All the patients underwent cystoscopy with transurethral biopsy and 14 had subsequent cystectomy. In comparison with other sequences, FLAIR sequence was more sensitive in the detection of bladder neoplasms. This sequence demonstrates the hyperintense signal of bladder neoplasms from the filled bladder lumen with no signal. The sensitivity in the identification of bladder neoplasms was 100% with FLAIR sequences, 89.6% with TSE T2-weighted sequences and 86.2% with TSE T1-weighted sequences. That was due to the higher signal-to-lesion ratio of FLAIR sequences in comparison with the others. In fact, on FLAIR sequences the mean value of contrast to lesion ratio of bladder neoplasm was 33.1 while on SE T1-weighted sequences and TSE T2-weighted sequences was, respectively, 15.2 and 29.2. FLAIR sequences allowed the detection of small papillomas (< 2 mm). TSE T2-weighted sequences were more sensitive than other sequences in the study of bladder wall infiltration. Conclusion: FLAIR sequences were more sensitive in the detection of bladder neoplasms, thanks to their higher contrast-to-lesion ratio and were helpful in the visualisation of small papillomas, especially when multifocal. While the inter-reader reproducibility of 2D-DM resulted only moderate, the adjunction of DBT allowed to reach a substantial reproducibility. The use of DBT added to 2D-DM can reduce inter-reader variability and allow for more reliable readings from different radiologists. The oblique coronal scans were parallel to the plane of the bladder neck. 15 patients underwent also voiding MR-cystourethrography performed with T1-weighted spoiled 3D gradient-echo acquisitions on sagittal plane performed after the filling of bladder lumen with contrast-material-enhanced urine. The entire MR examination lasted no longer than 10 minutes. We detected 18patients with abnormality of smooth muscular structures of the bladder neck and 3 with bladder neck cyst. MRI allowed a perfect evaluation of the different smooth detrusor muscles of the bladder neck. In patients with urinary bladder neck dysfunction, we detected hypertrophy of posterior smooth muscular structures of bladder neck and kyphosis of prostatic urethra. 6 patients were able to perform voiding MR-cystourethrography that showed the characteristic radiological features. Conclusion: MRI with voiding MR-cystourethrography could be performed in male patients with bladder outlet obstruction in order to visualise the aspect of the B-0692 10:57 Purpose: The non-invasive investigation of urinary bladder carcinoma by magnetic resonance (MR) virtual cystoscopy was evaluated by us and compared with conventional cystoscopy. Methods and Materials: Thirty consecutive patients, presenting with gross haematuria and trans abdominal ultrasound suggestive of mass in the bladder were taken up for study. All patients underwent conventional cystoscopy and CISS 3D MR imaging and the images reconstructed for virtual cystoscopy using volume rendering technique. Lesions were detected and the number, size, location and morphologic features of lesions were noted. Subsequently, patients underwent conventional cystoscopy, and the findings were noted. The final diagnosis of the cases was established by histopathology. Results: Sixty-five lesions were seen in MR virtual cystoscopy and 69 in conventional cystoscopy. The smallest lesion identified on MR virtual cystoscopy was 3 mm. Overall sensitivity and specificity of MR virtual cystoscopy for lesion detection were 94.2 and 100%, respectively. For lesions greater than 5 mm, the detection rate was 98%.Pearsons correlation test showed a good between virtual and conventional cystoscopy for maximum and minimum diameters of the lesion (0.98 and 0.92, respectively). Location of the lesions and their morphological characteristics were found to correspond by both methods. Conclusion: MR virtual cystoscopy is an effective tool in the detection of urinary bladder tumours, especially those larger than 5 mm. When bladder lesion is less than 5 mm a sessile conventional cystoscopy is better than MR virtual cystoscopy. Purpose: To evaluate the diagnostic accuracy of a diagnostic imaging technique called voiding MR cystourethrography. Methods and Materials: 10 normal volunteers and 86 male patients with bladder outlet obstruction (evaluated with urine-flow velocity recording) underwent voiding MR cystourethrography. The MR examination was performed with 1.5 T superconductive magnet. The filling of the urinary bladder with paramagnetic contrast agent was obtained by the i.v. administration of furosemide followed by ¾ of the normal dose of a paramagnetic contrast agent. During the micturition two consecutive T1-weighted spoiled 3D gradient-echo acquisitions on sagittal plane were performed. 3D row images were post-processed with MIP algorithm. 25 patients performed retrograde and micturating conventional cystourethrography in the month preceding MRI. Results: Homogeneous opacification of the bladder lumen was always obtained. 10 patients were unable to perform the MR examination. In all the volunteers and in all the patients studied (76 pts), a perfect evaluation of the male urethra with MRI was obtained and its visualisation with MIP reconstructed images was considered comparable to that obtained with conventional cystourethrography. Site, length and number of urethral strictures were accurately determined. The analysis of 3D sagittal scans allowed a better evaluation of the morphology of the urethral strictures in comparison with conventional cystourethrography. Conclusion: Voiding MR cystourethrography demonstrates the morphology of the bladder neck and urethra during the micturition and can substitute standard cystourethrogram, avoiding radiation exposure to the gonads and urinary catheterization. Image quality on liver CT based on sinogram-affirmed iterative reconstruction algorithm B. Schulz, B. Bodelle, P. Siebenhandl, M. Beeres, F. Al-Butmeh, C. Frellesen, T.J. Vogl; Frankfurt a. Main/DE (mail@borisschulz.com) Purpose: To evaluate efficiency of sinogram-affirmed iterative reconstruction technique, regarding noise and image quality on contrast-enhanced computed tomography (CT) of the liver. Methods and Materials: CT examinations were performed upon 32 patients (128 slice CT, 120 kV, 180 mAs, activated tube current modulation, 0.6 mm collimation). Each examination was reconstructed at standard filtered back projection (FBP) and 5 different SAFIRE strengths in 5 mm images in transversal direction with soft tissue kernel. Image noise was defined as standard deviation (SD) of Hounsfield units (HU) in air, and signal-to-noise ratio (SNR) of the liver was defined as mean liver HU per liver SD. Subjective image quality was evaluated by three raters using a 5-point scale (1=non-diagnostic image quality, 5=excellent image quality). Results: Average image noise was 6.2 HU (FBP), vs. 5.7 HU (SAFIRE 1), vs. 5.0 (SAFIRE 2) 4.4 HU (SAFIRE 3), 3.8 HU (SAFIRE 4), 3.1 HU (SAFIRE 5). SNR of the liver consecutively increased when using the iterative reconstruction algorithms from 8.4 (FBP) to 9.3 (SAFIRE 1) to 10.4 (SAFIRE 2) to 12.2 (SAFIRE 3) to 15.1 (SAFIRE 4) to 17.5 (SAFIRE 5). The differences in image noise and SNR of each SAFIRE-strength to FBP was statistically significant (p < 0.05). Subjective image quality was voted 3.9 (FBP) vs. 4.3 (SAFIRE 1) vs. 3.7 (SAFIRE 2) vs. 2.8 (SAFIRE 3) vs. 1.8 (SAFIRE 2) vs. 1.2 (SAFIRE 5). Conclusion: Sinogram-affirmed-based iterative reconstruction technique significantly reduces image noise and increases SNR for examinations of the liver. However, subjective image quality decreases with strong iterative strengths. bladder neck. These anatomical information are useful to determine the causes of voiding obstruction and diagnose urinary bladder dysfunction. MRI findings of radiation-induced changes in the urethra and periurethral tissues in patients with prostate cancer C. Marigliano 1 , O.F. Donati 2 , O. Akin 2 , D. Goldman 2 , J. Eastham 2 ; 1 Rome/IT, 2 New York, NY/US Purpose: The aim of this study was to assess radiotherapy (RT)-induced changes in the urethra and periurethral tissues in patients with prostate cancer (PCa). This retrospective study included 108 men (median age, 65y; range, 43-87y) who underwent external-beam radiotherapy (EBRT) and/or brachytherapy for PCa. On endorectal-coil MRIs of the prostate obtained within 180d before RT and 2-63 months (median, 20 months) after RT, two readers independently measured the urethral length (UL) and graded the margin definition (MD) and signal intensities (SIs) of the urethral wall, the levator ani and obturator internus muscles and the muscles of the genitourinary diaphragm on 4-point scales. Results: Mean UL decreased significantly from pre-to post-RT MRI for both readers (from 15.2 to 12.6 mm and 14.4 to 12.9 mm, [p < 0.0001, both]). Inter-reader agreement for UL was excellent for pre-and post-RT MRI (ICC= 0.89 and 0.90, respectively). Both readers found significantly decreased MD and increased SI in the urethral wall and pelvic muscles on post-RT MRI (p?0.008). Inter-reader agreement was fair for MD (?=0.31, pre-and post-RT) and SI of the urethral wall (?=0.33, pre-and post-RT) and ranged from slight to moderate for SI of the pelvic muscles (?=0.11-0.56, pre-RT and?=0.11-0.46, post-RT). SI changes in the obturator internus muscle were greater after EBRT (p=0.0003-0.01), while SI changes in the levator ani muscle were greater after brachytherapy (p=0.03). Conclusion: After RT of the prostate, MRI shows urethral shortening, decreased urethral margin definition and increased SI of the urethral wall and pelvic muscles. MRI anatomic evaluation in patients with persistent urinary incontinence after advance male sling: a work in progress study with a 3 T system V. Zampa, D. Pistolesi, S. Ortori, L. Faggioni, M. Marletta, C. Bartolozzi; Pisa/IT (virnazampa@hotmail.com) Purpose: Retrourethral transobturator sling is a new functional treatment of stress urinary incontinence after prostatectomy consisting in repositioning the urethral sphincter into the pelvis. Overall success rate is 54-80%; however, a failure rate of 20-45% is reported. The aim of this study was to retrospectively analyse morphologic changes visible on MRI after sling procedure in incontinent patients and compare with the continent ones, in order to detect possible factors explaining the different clinical outcome. Methods and Materials: 16 patients treated with advance sling were enrolled: 8/16 had clinical recovery while 8/16 had persistent incontinence. MR protocol performed with a 3 T system included 3D T2w sequence (cube) and a high temporal resolution Fiesta for dynamic MRI. On the T2w sequence, the length of the bulbus posterior to the sling and the distance of the sling from a line parallel to the symphysis pubis (LSP), were measured. Mann-Whitney test was used to analyse the results. Results: In the 8 incontinent patients the length of the bulbus posterior to the sling was < 8 mm (range 4-8 mm) while in the continent ones was > 12 mm (12-23 mm) (p < 0.001). The sling position was located posterior to the LSP in 7/8 incontinent patients (4-12 mm) and almost coincident in 6/8 continent patients (p=0.04). Conclusion: Based on our results, the length of the bulbus posterior to the sling seems to strongly correlate with continence. Although our results must be confirmed in a larger series, surgeons should consider this element in planning the proper position of the device. of the patient and type of examination semiautomatically. In addition, 40 abdominal CT examinations were performed with a standard tube potential of 120 kVp. Radiation doses (CTDIvol) were noted for all examinations. Signal-to-noise ratio (SNR) was determined in the contrast-enhanced lumen of the abdominal aorta (A), liver (L) and spleen (S). Subjective IQ (lesion detectability, diagnostic confidence) was rated on a 4-point scale (1_non diagnostic; 4_excellent) by two readers. Results: Whereas noise level was slightly elevated when using TPS algorithm compared to the standard protocol (10.2 vs. 8.0 HU, p < 0.01), no significant differences in SNR (15.2±5.4 vs. 16.5±5.2 [A], 10.5±3.3 vs. 11.7± 3.9 [L], 10.8±3.8 vs. 12.0±3.9 [S]) were observed between the two protocols. Subjective IQ (mean score of 3.9 versus 3.8, respectively) was good to excellent in all examinations. TPS lowered the CTDIvol significantly as compared to standard abdominal CT (6.1±1.7 mGy vs. 11.0±3.9 mGy, p < 0.01). Conclusion: Attenuation-based TPS lowers the dose of abdominal CT in clinical routine by up to 45% while maintaining high subjective and objective image quality. Second generation dual-energy CT of the abdomen: radiation dose comparison with 64-and 128-row single energy acquisition C.N. De Cecco, A. Darnell, N. Macias, G. Muscogiuri, C. Ayuso, A. Laghi; Rome/IT (g.muscogiuri@gmail.com) Purpose: This study was designed to compare the radiation dose in abdominal dual-energy (DE) and single energy (SE) acquisitions obtained with a dual-energy CT (DECT) and a 64-row CT (SECT). A total of 130 patients divided into two groups underwent precontrast and portal abdominal 128-row CT examination. In group A, DE portal acquisition was performed; group B underwent SE portal acquisition. Group C was compound of 32 subjects from group A studied with 64-row SECT. In each group, the portal phase dose length product (DLP) and radiation dose (mSv) were calculated. Results: A significant radiation dose increment (p < 0.05) was observed in group A 10.2±2.3 mSv in comparison to group B 8.9±2.4 and group C 8.8±1.9 mSv. No significant difference (p> 0.05) was reported between SE 64-and 128-row acquisitions. A significant positive correlation between radiation dose and BMI was observed in each group (group A, r2=0.59, p < 0.0001; group B, r2=0.35 p < 0.0001; group C, r2=0.20, p=0.0098). In clinical practice, abdominal DE modality delivers a significant higher radiation dose to the patient compared to 64-and 128-row SE acquisition. The radiation increment can be justified if a real advantage in patient diagnosis is obtained using DE information. Can iterative reconstructions improve the detection of small hypervascular liver nodules with dual-energy CT? L. Facchetti 1 , L. Berta 2 , L. Mascaro 1 , F. Pittiani 1 , L. Romanini 1 , R. Maroldi 1 ; 1 Brescia/IT, 2 Milan/IT (facchettil@gmail.com) Purpose: To optimise Dual-Energy CT (DECT) protocols with Sinogram Iterative REconstruction (SAFIRE) algorithms for improving small hepatocellular carcinoma (HCC) detection. A DECT arterial acquisition of a cirrhotic patient was reconstructed using the standard filtered back projection (FBP-B20f) and 3 iterative reconstructions both for the whole dose protocol (DE composition 0.5) and for 80-kV acquisitions. Each one of the iterative medium-smooth filter (I26-I30-I31) was reconstructed at 3 different strengths (S3-S4-S5) for a total of 20 image series. For each series, 8 virtual spherical lesions were simulated in random positions on the liver. A lesion-to-liver contrast (LLC) of +20 HU was selected for DE-composition 0.5 and +30 HU for 80 kV, according to a preliminary study on 20 HCCs acquired with DECT. Four expert radiologists performed a detectability test and rated the overall quality, noise and sharpness (5-point scale) in all images. Results: 2/32 lesions were detected with FBP-B20f. In all the iterative reconstructions, the strength-5 kernels led to detect 23±1.2/32 lesions. The highest image quality ratings were 3.3±1.3 (B20f), 3.5±0.7 (I30-S3 DE-composition 0.5) and 3.1±1.2 for I30-S5 DE-composition 0.5, without a statistical difference (ANOVA test). All subjective ratings in the 80 kV series were defined as suboptimal (2.3±0.3). Conclusion: Iterative reconstructions increase the sensitivity of the detection of sub-centimetric low-contrast lesions, even in the 80-kV series delivering half dose. The I30-S5 reconstruction was considered the best for the routine protocol. Efficacy of a liver detection algorithm for noise reduction in abdominal CT N. Ardley 1 , K. Buchan 2 , K. Lau 1 ; 1 Clayton/AU, 2 Melbourne/AU (Nicholas.Ardley@southernhealth.org.au) Purpose: The liver, an inherently low contrast structure, appears 'noisy' on routine CT of abdomen. This may impede liver lesion detection. The development of a specific CT liver detection algorithm delivers higher radiation exposure to the liver with the aim of improving quantum noise, and correspondingly less radiation to the remaining abdomen. The aim of this study was to assess the efficacy of this algorithm on reducing noise in the liver. Methods and Materials: 80 consecutive patients for abdominal CT with same level of iterative reconstruction were included. There was no exclusion. The CT liver detection algorithm was enabled in the last 40 of these patients. Region of interest in Hounsfield units and standard deviation (SD) were measured in the left and right lobes of liver, spleen, psoas and bladder for all patients. Radiation doses were also recorded. The results of the two groups were compared. Results: SD reflected noise. In the liver detection algorithm group, there was a SD reduction by 10.1% in the right liver, 15.61% in the left liver and 15.83% in spleen. No significant change of SD was seen in psoas and bladder. A 5.6% overall radiation dose reduction was noted in this group. The application of this newly developed CT liver detection algorithm demonstrated a reduction in noise in the liver and spleen with no significant noise changes in the remaining abdomen. There was an added benefit of overall radiation dose reduction. Author Disclosures: K. Buchan: Employee; Philips Healthcare. Impact of modified abdominal CT protocols for obese patients with filtered back projection and hybrid iterative reconstruction technique on image quality, radiation dose and low-contrast detectability: a phantom study S.T. Schindera 1 , D. Odedra 2 , D. Mercer 2 , S. Thipphavong 2 , P. Chou 2 , Z. Szucs-Farkas 3 , P. Rogalla 2 ; 1 Basle/CH, 2 Toronto, ON/CA, 3 Biel/CH (sschindera@aol.com) Sunday data were collected in a time period of 5-40 minutes for the T1w sequences. Volunteers underwent subsequent T2w respiratory-gated MRC on a 3 T MRI. For qualitative analysis a 5-point scale was used. Contrast ratios were calculated for quantitative assessment. Results: Contrast-enhanced T1w MRC at 7T showed a homogeneous depiction of the intra-and extrahepatic biliary tract with a maximum enhancement 20 minutes post-contrast. VIBE and FLASH IR provided a good image quality for the intra-(VIBE 3.60, FLASH IR 3.67) and extrahepatic bile ducts (VIBE 3.50, FLASH IR 3.72). Quantitative analysis revealed high CR values for FLASH IR (CR 0.41 intrahepatic and 0.45 extrahepatic) due to a strong signal decrease of hepatic tissue and vessels. T2w TSE at 7T revealed a poor image quality without diagnostic potential (2.22 intrahepatic, 1.93 extrahepatic). 7T VIBE and FLASH provided superiority in the depiction of the intrahepatic bile ducts, while 3 T MRC was superior in the delineation of the extrahepatic biliary tract. Conclusion: Our results demonstrate the feasibility of contrast-enhanced imaging of the biliary ducts at 7T, particularly T1w FLASH with inversion recovery enables high-quality assessment of the biliary tract. Purpose: Volume rendering 3D-magnetic resonance imaging (MRI) is able to show auditory pathways between the cochlea and the cerebellopontine angle in children with negative auditory brainstem responses and cochlear nerve structures undetectable by conventional high-resolution (HR) MRI. Methods and Materials: Twelve children (mean age ± 43.8 mo) with confirmed severe hearing loss by ABR (auditory evoked brainstem responses) underwent HR-CT and HR-MRI of the petrous bone. In addition, three-dimensional T2-weighted turbo spin-echo axial slices were obtained at 1.5 T and maximum intensity projections and 3D volume reconstructions were performed for visualisation of the cochlear anatomy. Results: Abnormal cochleovestibular anatomic findings such as incomplete partition type I (n=1), incomplete partition type II (n=1), narrow internal auditory canal (n=3), splitting of the internal auditory canal and concomitant anomalies of the posterior labyrinth (n=2) were detected by HR-CT and HR-MRI. Interestingly, volume-rendered 3D inner ear reconstructions detected varying but communicating structures of the cochlea and the brainstem in all 12 cases. After cochlear implantation all twelve children showed obvious hearing reactions. Conclusion: In contrast to conventional HR-MRI, 3D-MRI volume-rendering reconstructions are useful to detect aberrant and even tiny auditory path structures derived from the cochlea. Children with severe hearing loss and HR-MRI-based findings of missing cochlear nerve structures should be further screened with volume rendering 3D-MRI during cochlear implantation evaluation. Purpose: Cochlear nerves aplasia represents a rare but possible congenital cause of Sensori Neural Hearing Loss (SNHL) in children. Early identification and accurate diagnosis are mandatory to correctly select auditory brainstem implantation (ABI) candidates. The purpose of the study was to evaluate the contribution of a complete pre-operative radiological assessment based on CT and MRI to prevent misdiagnosis and erroneous treatments. Purpose: To correlate patient diameters and subjective image quality in low-voltage and standard-voltage CT of the upper abdomen in the same patient population, with the goal of identifying cutoff patient diameters for selecting patients for lowvoltage scans. Methods and Materials: 32 patients underwent MDCT of the abdomen with arterial phase at 80 kV with angular dose modulation on 64-row MDCT (test group). This was compared to a previous 120-kV scan on the same scanner. Mean interval between scans was 139 days. Patient transverse and sagittal diameters were measured at celiac axis level, and the mean was calculated. Two radiologists by consensus graded image quality on a 5-point scale (5=excellent; 4=good; 3=moderate; 2=poor; 1=non-diagnostic; 3 was the chosen cutoff quality). Image quality was correlated to the transverse, sagittal and mean diameter by means of an ANOVA test. Results: Patient diameters were unchanged across exams (all p=ns). In 80-kV scans, image quality was significantly correlated to sagittal (p=0.034) and mean diameters (p=0.025), while a trend to significance was observed for transverse diameter (p=0.053). In 120-kV scans, image quality was not significantly correlated to patient diameters (all p=ns), and all patients received grade 4 or 5. In 80-kV scans, a subjective grade 3 corresponded to a transverse diameter of 329 mm and a sagittal diameter of 267 mm. Conclusion: Subjective image quality in low-voltage scans appears to be more influenced by patient size than at standard voltage scans. For our protocol, cutoff diameters for adequate image quality are transverse 329 mm and sagittal 267 mm. Author Disclosures: G.A. Zamboni: Speaker; Guerbet. Preliminary application of spectral CT imaging in the differentiation of hepatic tumours W. Chen, X. Ye, C. Zhou; Beijing/ CN (wenchen0629@yahoo.com.cn) Purpose: To investigate the value of spectral CT imaging in differential diagnosis of hepatic tumours. This prospective study was Institutional Review Board approved with patient consent. Thirty-eight patients with hepatic tumours (22 men, 16 women, 63 lesions), including 11 patients with hepatocellular carcinoma (HCC), 17 with hemangioma (HH) and 10 with metastatic tumour (MT), underwent plain scan of spectral CT imaging and conventional contrast CT scan. Contrast-to-noise ratio (CNR) of different energy levels and homologous keV of optimal CNR were calculated by the spectral analysis software. The authors also chose three regions (60-80keV, 50-90keV and 40-100keV) and calculated the slope rates of spectral curves. One-way ANOVA followed by LSD post hoc tests were performed to compare parameters among HCC, HH and MT groups. The homologous keV of optimal CNR of HCC, HH and MT groups were 68.71±1.72, 67.23±1.93 and 67.16±2.79, respectively. The slope rate of 60-80-keV region in HCC group (0.446±0.201) was significantly higher than that in HH group (0.205±0.209). There were significant differences between HCC, HH and MT groups in the slope rates of 50-90-keV and 40-100-keV regions (p < 0.05). The slope rates were 0.481±0.199, 0.202±0.213 and 0.344±0.229, respectively, in 50-90-keV region and 0.565±0.231, 0.222±0.289 and 0.396±0.260, respectively, in 40-100-keV region. The 65-70-keV monochromatic imaging of spectral CT imaging is the best for detection of hepatic tumours and slope rates of spectral curves may be useful in differentiation of hepatic tumours. Purpose: To assess the feasibility of magnetic resonance cholangiography (MRC) using biliary secreted gadoxetic acid at 7 Tesla (T) and to compare it to T2-weighted (w) MRC at 3 T. Methods and Materials: 10 healthy volunteers were examined on a 7T MR-system. T2w TSE, T1w VIBE and FLASH with inversion recovery (IR) were acquired in coronal orientation. For dynamic imaging gadoxetic acid was administrated and S31 C A D E F G B 6-GKR=2*10 5 a.u. (p < 0.05); WiPI values were: b-GKR=8*10 7 cm 3 /sec, 3-GKR=2*10 8 cm 3 /sec (p> 0.05), 6-GKR=6*10 6 cm 3 /sec (p < 0.05). 6-GKR mean diameters decreased in 8/10 patients, 6-GKR CEUS parameters (PE, WiR, WiPI) decreased in all patients. Conclusion: A reduction in PE, WiR and WiPI at 6 months after GKR suggested a depletion in tumour vascularization due to radiotherapy-induced necrosis. Our preliminary results showed the feasibility of CEUS perfusion analysis for UM, which could provide reproducible, reliable and earlier parameters for the assessment of tumour response to GKR. Evaluation of lacrimal drainage system obstruction using combined multidetector CT and instillation dacryocystography M. Shweel, A. ElShafaey, M. Nasar, R. MohyElDien; ElMinia/EG (mohshweel@yahoo.com) Purpose: To assess the use of combined multidetector computed tomography and instillation dacryocystography (CTDCG) in detection of the level of lacrimal drainage system (LDS) obstruction. Methods and Materials: Twenty-one patients with one-sided epiphora were our candidates for CTDCG. Axial source and post-processing images were assessed for clear viewing and the ability to detect the level of LDS obstruction. To our knowledge, no previous studies used this combination in the assessment of the LDS obstruction. Results: All patients tolerated the examination well. Various levels of LDS obstruction were detected, common canaliculus in 4 (19%) patients, lacrimal sac in 3 (14.2%), junction between lacrimal sac and NLD in 9 (42.8%) and NLD obstruction in 5 (23.8%) patients. The most common CTDCG findings were dilated opacified lacrimal sac with no opacification of the nasolacrimal duct (NLD) in 9/21 (42.8%) patients. Curved planner reformation (CPR) was excellent to detect the nasolacrimal duct (NLD) obstruction. Conclusion: CTDCG is a non-invasive patient friendly procedure that adds benefit in documentation and preoperative planning. Parotid gland tumours shear wave elastography: a preliminary study S. Espinoza-Boireau, I. Khettab, A. Lacan Melki, P. Halimi; Paris/FR (sophie.espinoza@gmail.com) Purpose: To assess the feasibility of parotid gland tumours shear wave elastography. To establish normal parotid gland elasticity. To evaluate elasticity for the most common benign parotidian tumours (pleomorphic adenoma, Warthin's tumour) and malignant tumours. Methods and Materials: Prospective study including 30 consecutive patients with parotid gland tumour. They all underwent share wave elastography to measure tumour elasticity and contralateral normal parotid gland elasticity. The results were confronted with histological analysis or fine-needle aspiration cytology. Results: Elasticity measure was feasible in all cases. Mean normal parotid gland elasticity was 7 kPa (n=25; 3-15). Benign tumours elasticity was 17.8±8 kPa (n=18). Malignant tumours elasticity was 37±18 kPa (n=3). Pleomorphic adenomas elasticity was 15.3±8 kPa (n=12). Warthin's tumours elasticity was 21.8±7.4kPa (n=6). Conclusion: Benign and malignant tumours seem to behave differently under shear wave elastography. Complementary studies are required to establish relevant threshold values allowing proper elastography lesions discrimination. Does heterogeneous echogenicity of the thyroid parenchyma influence the detection of multifocality and bilaterality for papillary thyroid carcinoma on preoperative ultrasound staging? S. Herh, E.-K. Kim, H. Moon, J. Kwak; Seoul/KR (jinnyhs@hanmail.net) Purpose: This study was to evaluate whether heterogeneous echogenicity of the thyroid parenchyma can influence the diagnostic performances of ultrasonography (US) in detection of multifocality and bilaterality of papillary thyroid carcinoma (PTC). Between December 2010 and January 2011, 240 patients had preoperative staging US for PTC, and underwent total or near-total thyroidectomy. Seven experienced radiologists performed preoperative US for T and N staging. Underlying parenchymal echogenicity of the thyroid gland, multifocality, and bilaterality of the thyroid nodules were also evaluated. Patients were divided into two groups according to the underlying echogenicity of thyroid parenchyma on US. To evaluate the diagnostic accuracy of preoperative staging US according to the underlying thyroid echogenicity, diagnostic performances including sensitivity, with cochlear implantation without benefits. All the children performed pre-operative functional tests, temporal bone CT and brain/cerebellum-pontine angle (CPA) MRI. Results: MRI showed in all cases the absence of the cochlear branch of the eighth nerve bilaterally (38/38). Unilateral facial nerve aplasia was present in one patient. Associated inner ear malformations were present in 21/38 patients, in particular common cavity in 8/21, incomplete partition type 1 in 6/21 and semicircular canals malformations in 3/21. No brain anomalies were showed. CT scans better depicted the labyrinthine malformations, adding information about facial nerve canal and internal auditory canal (IAC) size. 2/38 CT showed normal inner ear structures and IAC size. Providing accurate information about cochlear nerve and brain anomalies is crucial in the pre-operative assessment of SNHL patients. MRI is the only radiological technique that is able to directly demonstrate the presence or the absence of cochlear nerves. CT is not fundamental and provides complementary information; a negative CT pattern cannot exclude a cochlear nerve malformation. Purpose: To test whether the size of the cochlear nerve measured in the internal auditory canal using three dimensional (3D) and multiplanar reconstruction (MPR) high-resolution MRI affects the speech recognition outcome following cochlear implantation. The study was retrospectively performed on 51 patients with longstanding hearing loss (mean age of 54.5 years). MRI was performed using a T2-weighted SPACE sequence. MPR and 3D reconstructions were performed using 3D and InSpace Applications, respectively. The preoperative cross-sectional surface area of the cochlear nerve was measured by drawing a region-of-interest around the circumference of the nerve. Speech recognition (SR) was tested using the Freiburger-Monosyllabic-Words (MSWT) and Numbers-tests (NT) preoperatively, postoperatively, at 3-, 6-and 12-month follow-up. SR and size assessment were performed in a double-blinded fashion. The correlation between the SR and nerve size were tested using Spearman's rank correlation test. Purpose: GKR efficacy in the treatment of UM, a hypervascular tumour, is conventionally assessed by clinical and ultrasound findings. Previous reports showed that, in case of hypervascular lesions (HCC, melanoma metastasis, etc). changes in vascularization precede diameters reduction after treatment. Hence, our aim was to evaluate CEUS in the quantitative assessment of tumour response to GKR. Methods and Materials: Ten patients, who underwent GKR, were enrolled. CEUS was performed (SonoVue Bracco) with iU-22 ATL (Philips) and 5-9 MHz linear probe at baseline, at 3 and 6 months after GKR (bGKR, 3-GKR, 6-GKR). Two main tumour diameters and different quantitative parameters related to blood volume (area under the curve in the wash-in phase; wash-in perfusion index -WiPI; peak enhancement -PE) and blood flow (mean transit time; wash-in rate -WiR; rise time -RT; time to peak) were evaluated using a dedicated software (SonoTumor Bracco). Purpose: To determine the value of semiquantitative strain elastography for the evaluation of chronic thyroiditis. The study was conducted on 48 consecutive patients with chronic autoimmune thyroiditis and 53 healthy controls. Semiquantitative strain elastography was performed to calculate the strain index value (strain ratio of the strap muscles to the thyroid parenchyma) to assess thyroid stiffness. For each lobe, measurements were obtained from upper, middle and lower part of the thyroid parenchyma. Mean strain ratio values of patients and healthy controls were compared by the Mann-Whitney U-test. Validity was analysed by receiver operating characteristic (ROC) curves. The median strain ratio value of patients with chronic autoimmune thyroiditis (2.22) was significantly higher than that of healthy controls (1.22; p < 0.001). The optimal cut-off value for the prediction of diffuse thyroid pathology was 1.41. For this cut-off value, thyroid stiffness had 90% sensitivity, 71.7% specificity, 75% positive predictive value (PPV) and 88.4% negative predictive value (NPV) for the presence of diffuse thyroid pathology. This cut-off point was exceeded by 89.6% of the patients with and 28.3% of the subjects in control group. SI values showed mild positive correlation with the TSH levels (Spearman r coefficient = 0.265). However, this difference did not reach statistical significance (p=0.069). Conclusion: Semiquantitative Strain Elastography seems to be a useful method for the assessment of Chronic Thyroiditis. Further studies are warranted in larger patient groups to determine the reliability of sonoelastography in patients with chronic thyroiditis. Purpose: To retrospectively assess the detection rate of intracranial hematomas achieved with the use of curved MIPs of the meningeal spaces, compared to reading transverse CT sections only. This retrospective study was approved by the Institutional Review Board of our institution, which waived informed consent. 314 consecutive patients who underwent CT imaging for cranial trauma (n = 314; 155 men and 159 women; mean age, 58 ± 24 y; range, 2 -98 y) were included. Four curved MIPs of the meningeal spaces with different thicknesses were rendered for each patient. Four radiologists independently evaluated all cases. Hematomas of less than 3 mm thickness were considered 'thin' throughout this study. The radiologists were blinded to patient names, and patient and group order was randomised. The results were compared to a standard of reference built by two experts. Logistic regression with repeated measurements was used for statistical analysis. Results: 121 intracranial hematomas were confirmed in 39 patients. For all readers, the reading time for hematoma detection was significantly shorter (3 -5 times, P <.001)) for curved MIPs. The mean lesion-based detection rate of all readers was 80% (193/242) for transverse sections and 83% (200/242) for curved MIPs. For thin hematomas, the mean detection rate rose from 20% (8/40) with transverse sections to 83% (33/40) with curved MIPs. specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated and compared among the two groups. Results: Of the 240 patients, underlying echogenicity of thyroid was heterogeneous in 55 patients (22.9%), and homogenous in 185 patients (77.1%). Forty-four (18.3%) of the 240 patients had multifocal lesions in one lobe, and 77 (32.1%) had bilateral lesions on pathologic examination. Diagnostic performances of preoperative staging US did not show significant differences in detecting multifocality and bilaterality between patients with homogenous and heterogeneous parenchymal echogenicity. Conclusion: Heterogeneous echogenicity of underlying thyroid parenchyma does not significantly influence the detection of multifocality and bilaterality for PTC on preoperative US staging. Role of elastography in the characterisation of thyroid nodules F. Sogaro, P. Tessitore, A. Scrimieri, F. Pittiani, A. Borghesi, R. Maroldi; Purpose: This study aimed at evaluating the reliability of elastography in predicting malignancy of thyroid nodules. Methods and Materials: 59 patients with thyroid nodules, who underwent to grey-scale ultrasonography (US), elastography and FNC (Fine-Needle Cytology), were prospectively enrolled from February to August 2012. For each nodule, grey-scale US parameters (hypoechogenicity, absence of halo sign, absence of colloid) were examined. Findings at elastography were classified according to Rago criteria (2010). Cytological diagnosis were classified according to the SIAPEC-IAP criteria in Tir1, Tir2, Tir3, Tir4 and Tir5. The diagnostic performance of grey-scale US and elastography were compared with cytological findings. Tir1 and Tir3 with indeterminate cytology were excluded from the study. Results: 48 nodules were included: 41 Tir2, 3 Tir4 and 4 Tir5. According to Rago criteria 32 nodules were score 1, 2 nodules score 2 and 14 nodules score 3. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of elastography were 71%, 78%, 35%, 94%, respectively. The combination of grey-scale US parameters (hypoechogenicity with absence of halo sign and colloid) showed 57% sensitivity, 76% specificity, 28% PPV and 91% NPV. Conclusion: Elastography is not useful in the differentiation of malignant and benign thyroid nodules. However, elastography had a high probability in predicting cytological benign diagnosis (high VPN). Moreover, elastography demonstrated a superior performance than the combination of grey-scale US parameters. The new approach to thyroid elastosonography -time-strain curvesmay aid the differentiation of nodules R.Z. Slapa, B. Migda, W.S. Jakubowski, J. Bierca, J. Slowinska-Srzednicka; Warsaw/PL (rz.slapa@gmail.com) Purpose: To evaluate a new linear/non-linear approach to strain elastosonography of thyroid nodules, based on the analysis of time-strain curves and to compare it with classical elasticity score and thyroid strain ratio methods. Methods and Materials: During 2009-2011, 67 patients scheduled for thyroidectomy (62 with multinodular goitre and 5 with single thyroid nodule) were evaluated with B-mode and power Doppler ultrasound of the whole thyroid. During ultrasound examination, 96 dominant nodules were examined with strain elastosonography with Aplio XG with linear 5-17 MHz transducer. The stiffness of each thyroid nodule was evaluated with classical features of strain elastosonography qualitatively (with elasticity scores) and semi-quantitatively with thyroid tissue strain/nodule strain ratios with application of elasto Q. Moreover, a novel, original approach to elasticity data based on evaluation of time-strain curves was applied. Results: 7 papillary carcinomas, 89 benign nodules. Classical elastosonographic analysis with elasticity score and elasticity ratio on statistical analysis did not show significant difference between cancer and benign nodules (p-value, respectively, 0.431 and 0.156). On linear/non-linear analysis of time-strain curves excellent differentiation (p=5.6x10 -9 ) was possible with new parameter: the Relative Length of Non-Linear Relaxation. With threshold 0.5: sensitivity 100%, specificity 85.4%, area under ROC=0.975. The analysis of linear and non-linear elastosonography data may greatly improve differential diagnosis of thyroid nodules. Further large-scale studies evaluating the usefulness of linear/non-linear elastosonography phenomena (involving evaluation of vioscoelasticity, e.g. shear wave spectroscopy) in differential diagnostics of thyroid cancer are warranted. Methods and Materials: This HIPAA compliant retrospective study was IRB approved. We included 52 patients who had undergone emergent CT scans of the abdomen and pelvis for abdominal pain with tube current modulation, automated kVp selection and SAFIRE (Scan A) and compared their abdomen and pelvis CT scans with tube current modulation, 120 kVp, filtered back projection reconstruction algorithm (Scan B). CTDIvol, DLP, effective dose (DLP x k) and image noise values were compared between two protocols. Paired samples Wilcoxon test was used for analysis and P < 0.05 was considered significant. Results: The median CTDIvol were 12.73 mGy and 18.26 mGy for Scans A and B, respectively (P=0.0002); the median DLPs for Scans A and B were 583.00 mGycm and 888.50 mGycm (P < 0.0001), respectively. The median effective dose was 34.38% lower with Scan A compared with Scan B (8.74 mSv vs. 13.32 mSv, P < 0.0001). The median image noise was significantly lower with Scan A using SAFIRE (11.05 vs. 14.15, P < 0.0001). Results: 100 kV were automatically selected in 82 patients, 120 kV in 12 patients and 140 kV in 6 patients of the autokV group. Patient diameters increased with higher kV settings. The average CTDIvol (9.4 vs. 12.9 mGy) and DLP (669 vs. 925 mGycm; p < 0.05) in the entire autokV group were 27%/28% lower than in the group with fixed 120 kV. This effect was even more pronounced in the patients in whom 100 kV were selected (CTDIvol 8.1 mGy, -37%; DLP 571 mGycm, -38%). Enhancement of parenchymal organs gradually increased with lower kV, while image noise was at a stable level. Conclusion: Software-based automated selection of the tube potential allows for significant dose savings in thoraco-abdominal trauma CT while image quality is maintained or even improved. Especially younger patients involved in accidents may benefit the most from this development. Usefulness of low-dose CT with or without adaptive statistical iterative reconstruction ( Purpose: To determine the usefulness of low-dose CT in the diagnosis and exclusion of acute appendicitis and to compare with low-dose CT taken with ASIR. Conclusion: Curved MIPs of the meningeal spaces have the potential to shorten the detection time for epi-and subdural hematomas, increase sensitivity, especially for thin hematomas, and reduce the required operator experience for detection. Author Disclosures: H. Ringl: Patent Holder. Simple and easy way using time-intensity curve of perfusionweighted images to find penumbra in stroke patients within 4.5 hours of onset due to the carotid artery occlusion T. Mori, T. Iwata, Y. Miyazaki, M. Nakazaki, Y. Takahashi; Kamakura/JP (morit-koc@umin.net) Purpose: The aim of our study was to investigate whether or not time-intensity curve (TIC) of PWI can find penumbra in stroke patients with acute carotid artery occlusion. Methods and Materials: Included were patients 1) who were admitted within 4.5 hours of onset between January 2006 and January 2011, and 2) in whom emergency MRA suggested the affected carotid artery occlusion. We assessed, NIHSS on admission (NIH adm), DWI-ASPECT score, TIC types, successful recanalization (SR), NIHSS on the 7 th day (NIH 7 th ), and in-hospital death. Early neurological improvement (ENI) was defined as NIH adm-NIH 7 th > 0. TICs were generated on region of interests set at symmetrical positions of the bilateral MCA territories. According to the time to peak (TP) and the peak signal (PS) comparing the affected side (a) with the contralateral side (c), we classified TIC into four types and defined type 1 as TPa>TPc and PSaTPc and PSc/2TPc and PSa>PSc, and type 4 as TPa=TPc. Relationship between TIC types, in-hospital death and ENI were assessed. Results: Eighty-seven patients were analysed. There were 36, 39, 12 and 0 patients in TIC type 1, 2, 3 and 4, 39 patients underwent reperfusion therapy (RT) and SR was achieved in 18 patients, and 29 patients died. TIC type 1 was the only determinant of in-hospital death (p < 0.01) and SR coupled with TIC type 2 was the determinant of ENI (p < 0.01). Conclusion: TIC type 2 means penumbra and type 1 predetermines poor clinical outcome. Author Purpose: Iterative reconstruction (IR) is a promising noise reducing technique with the potential to reduce radiation-dose with preserved study interpretability or improve image-quality at similar radiation-dose. One of the major drawbacks of IR is a longer reconstruction time which may be problematic in the emergency setting. The purpose of the current study was to compare reconstruction time and speed of IR and filtered back-projection (FBP) in two commonly encountered emergency imaging scan-protocols: total body trauma CT and pulmonary CTA. Methods and Materials: Fifteen patients underwent a total body CT after a traumatic event and twenty-five adults underwent a CTA for evaluation of pulmonary embolisms on a 256-slice CT-scanner. All data were reconstructed using FBP and two IR-levels (iDose 4 , Philips Healthcare). Quantification of reconstruction time and speed was done with a self-written plug-in for ImageJ (US National Institutes of Health). The mean delay in reconstruction time on total body trauma CTs was 44.4±8.1 and 44.9±7.0 seconds for iDose 4 -levels 1 and 6, respectively, and on pulmonary CTAs 10.1±9.6 and 12.0±11.8 seconds for iDose 4 -levels 2 and 4, respectively. The mean reconstruction time and speed for total body trauma CTs were 87.3±14.6, 131.7±16.7 and 132.2±17.9 seconds, and 20.1±1.6, 13.2±0.8 and 13.2±0.6 slices/s for FBP, iDose 4 -levels 1 and 6, respectively, and for pulmonary Munich/DE (sonja.kirchhoff@med.uni-muenchen.de) Purpose: In the past years the number of clinical-pathological autopsies decreased significantly due to various reasons. Forensic autopsies are disposed not only with regional differences but, however, also with on an average decreasing frequency. Especially in patients who died during trauma room management or emergency operation during critical care, no imaging could possibly be performed. Therefore, after termination of all clinical procedures a critical analysis of death and evaluation of the standards of medical care is often not possible, although especially regarding medical quality management it is highly desirable. At least to partly close this information gap we performed a post mortem Computed tomography (pmCT)study. In this prospective study whole body pmCT was performed in patients who died during trauma room management or emergency surgery leaving all installed foreign material, e.g. tube, drainage in place. The pmCT findings were compared with clinical findings and if available with autopsy reports as well. Results: Between 1999 and 2008 46 patients were enrolled, 18 of whom underwent additional autopsy. The major clinical diagnosis which had finally led to the termination of resuscitation procedures was confirmed by the pmCT findings. The autopsy report showed a high correlation in the corresponding cases to the pmCT-findings. Conclusion: PmCT offers the possibility to improve quality management during trauma room management regarding the decision for terminating resuscitation efforts by verifying the important clinical findings. In addition, pmCT findings support specifically the autoptic reporting. Purpose: To assess how the portrayal of radiology in medical TV shows is perceived by the general population. A survey was conducted among adult patients scheduled for a radiological examination, technologists and radiologists. The survey gathered information regarding TV watching habits and interest in medical TV shows. Questions addressing the accuracy in portraying radiology in comparison to reality (1-10 scale), appearance of radiological examinations and radiological staff were asked in regard to House M.D., ER, and Grey's Anatomy. The online survey conducted among radiologists and technologists from two different academic institutions served as reference standard. Results: A total of 126 patients and 240 professionals (133 technologists, 107 radiologists) participated. A moderate and significant correlation was found between the interest in medical TV shows and the perception that clinical reality was accurately portrayed in the group of patients (r=0.49, P=0.001) and technologist (r=0.38, P=0.001) but no correlation was found for radiologist (r=0.01). While > 60% in all survey groups noted the appearance of radiological examinations regularly to > 1/show, the appearance of radiological staff was perceived by 45.2-54.0% of patients, 31.6-47.4% of technologists and 15.9-23.4% of radiologists. ER was ranked more accurate than Grey's Anatomy or House M.D. The more interest in medical TV shows prevails in patients and technologists, the more are modern medical TV shows perceived as accurate in the portrayal of radiology. Radiological examinations are frequently utilised, but imaging is less often performed by radiological staff. This retrospective study includes 138 patients under 65 years-of-age with clinically suspected acute appendicitis, who underwent unenhanced low-dose CT on a 64 MDCT. 84 patients (group A) underwent a low-dose CT 34 patients (group B) underwent a low-dose CT with ASIR. Results: Normal appendix was identified in 52 (61.9.%) in A versus 26 (76.5%) in B. In A 22 (26.2%) versus 6 (17.6%) in B were diagnosed with appendicitis. In A 10 (11.9%) studies versus 2 (5.9%) studies in B the appendix was not identified. In those where the appendix was not identified a conventional CT was performed. No one had appendicitis during one month follow-up for negative studies. The sensitivity and specificity of CT low-dose were 88.1% and 100%, respectively, and for low-dose CT with ASIR 94.6% and 100%, respectively. The sensitivity increased to 100% for the total protocol for both techniques. The effective dose mean was 2.4 mSv ±0.8 instead of 2.62 mSv ±0.9. Conclusion: The low-dose CT is a suitable technique for the diagnosis or exclusion of acute appendicitis in young or middle-aged people, making possible inclusion as a radiological imaging test in the diagnostic algorithm of acute appendicitis. Introduction of the ASIR improves the low-dose CT technique with a higher sensitivity for appendix evaluation which increased the diagnostic confidence, slightly lowering the dose. The Purpose: To evaluate image quality of paediatric chest CT acquired at 70 kV. Methods and Materials: 130 consecutive children undergoing chest CT studies on a dual-source CT system were prospectively evaluated with a 70-kV scanning protocol. All scanning parameters were kept similar to those usually selected for standard 80-kV protocols, except the milliamperage. Always selected according to the patient's weight, ref mAs were increased by a factor of 1.6 to maintain comparable levels of radiation dose between newly introduced 70-kV and routine 80-kV protocols. Image quality at 70 kV (group 1) was compared to that of a paired paediatric population (group 2) based on the age (±1yr), weight (±1 kg) and administration of contrast material, previously scanned at 80 kV on the same CT unit and prospectively stored in our database. Group 1 and group 2 images were reconstructed with filtered-back projection. Results: Objective noise in group 1 was significantly lower than that measured in group 2 (9.9±6.3 HU vs 11.3±6.6 HU; p=0.03). Subjective image quality of lung and mediastinal images in group 1 did not significantly differ from that of group 2 (p=0.18). In group 1, the mean dose-length-product was 15.4±2.3 mGy.cm (< 1yr; mean weight: 5.3 kg) (n=35); 18.3±2.1 mGy.cm (1-5yr; mean weight: 13.4 kg) (n=44), 24.4±3.9 mGy.cm (5-10yr; mean weight: 24.7 kg) (n=33) and 31.7±4.7 mGy.cm (10-15yr; mean weight: 33.1 kg) (n=18). Conclusion: Paediatric chest CT at 70 kV provides similar objective and subjective image quality to that achievable at 80 kV. Results: From the records in the database, various anthropometric data were extracted, e.g. body mass and body length of more than 33000 patients, thoracic diameters and the volumes, densities and masses of lungs and mammalian glands of more than 2000 patients of all age groups. These data were compared to the anthropometric data of the mathematical MIRD phantoms provided by the Finnish centre for radiation safety STUK. It can be shown that in mathematical MIRD phantoms of all age groups, body mass, body length and thoracic diameters are overestimated, whereas lung volumes and lung masses are underestimated. Purpose: To assess the radiation dose delivered during dual-source chest CT examinations. We prospectively recorded the dose-length-product (DLP) of 506 consecutive children, evaluated in 4 age groups: group 1 (< 1yr; n=109; 21%) (mean weight: 5.33±1.99 kg), group 2 (1-5 yr: n=169; 33%) (mean weight: 13.35±3.92 kg), group 3 (5-10 yr: n=136; 27%) (mean weight: 23.77±6.36 kg) and group 4 (10-15yr; n=92; 18%) (mean weight: 36.83±7.78 kg). All CT examinations were performed with a dual-source CT system using a dual-source, single-energy scanning protocol obtained with thin collimation, high pitch and high temporal resolution, a weight-adapted selection of the kilovoltage and milliamperage, and systematic reconstruction of images using filtered-back projection. Results: Patients were scanned with a pitch of 2.0 (n=165; 33%) or 3.0 (n=341; 67%), at 80 kV (n=499; 99%) or 100 kV (n=7; 1%) with a milliamperage ranging between 40 and 90 mAs. The mean duration of data acquisition was 525.8±192.8 ms. CT examinations consisted of contrast-enhanced (n=190) and noncontrast (n=316) studies, obtained in the context of acquired (n=280; 55%) or congenital (n=46; 9%) bronchopulmonary disease, cystic fibrosis (n=60; 12%), cardiovascular disease (n=91; 18%), oesophageal atresia (n=8; 1%) and miscellaneous causes (n=21; 4%). All examinations were of diagnostic image quality. The mean DLP value in each age category was 14.29±3.38 mGy.cm ( Purpose: To standardise the scan protocol for CT scanners of participating centres in a multi-centre study (clinicaltrials.gov NCT01270074) for the prevention of radiologically defined bronchiectasis in CF infants by ensuring the maximum image quality at the minimum radiation dose. Methods and Materials: Three different sized phantoms (QRM, Germany) were used to assess scanners' performance of automatic exposure control (AEC). CTDI and DLP were recorded. The phantoms contained various inserts to assess slice-sensitivity-profile, in-plane spatial resolution, noise and the Hounsfield Unit (HU) scale. Scans were made for several dose levels and reconstruction kernels. Images were analysed with custom-made software (MatLab, USA) to obtain the standard deviation of the noise, point-spread-function (PSF) and slice thickness. Results: Eight different scanners with 64 slices or more from 4 manufacturers (GE, Philips, Siemens and Toshiba) were assessed. Despite differences in AEC's performance, we obtained approximately the same dose level at each center by recommending site and age-specific AEC reference levels. A constant image quality was only possible by matching the different reconstruction kernels measured PSFs at full-width-at-half-maximum. In fact, large part of the differences between scanners was related to reconstruction kernels. The relatively high noise images corresponded with reconstructions using a kernel with edge enhancement such as the Siemens B70 kernel or the GE lung kernel that are routinely used in chest imaging. Conclusion: Objective measurements on CT images allowed for matching of scan protocols among CT scanners of different manufacturers. Use of routine protocols might introduce a bias in the (automated) image analysis. Cystic fibrosis lung disease in children: correlation between MRI and HRCT scores C. Purpose: High-resolution computed tomography (HRCT) is known to be a sensitive means of detecting lung disease in cystic fibrosis (CF), with a significant radiation exposure. Magnetic resonance imaging (MRI) becomes increasingly important in the assessment of CF lung disease. The aim of this study was to establish the agreement between MRI and HRCT scores in a paediatric population. Methods and Materials: HRCT and T2 and post-contrast T1 MRI images were acquired on the same day from 17 CF patients (median age 12.7 years; range 9.1-20.2 years). Two radiologists with either > 20 (HDLP) or 3 years (CS) of ex-were analysed and compared with the corresponding real scan length. For selected CT scanners, radiation doses achieved during the scanograms were reconstructed using mathematical MIRD phantoms. Results: Depending on the patients´ age, many scanograms considerably exceed the real scan region, thus unjustifiably raising the radiation exposure of the patient. The radiation doses due to CT scanograms are not neglectible as, e.g. the whole body dose achieved during a thorax scanogram can exceed the whole body dose caused by a conventional chest x-ray examination by a factor of 10. Conclusion: An optimisation of scanogram lengths by defining specific anatomical landmarks for standard CT protocols, the optimisation of scanogram exposure parameters in paediatric CT examinations and their implementation into national and international guidelines seems to be necessary to fulfil the ALARA concept in paediatric CT. We established reference values for cardiac valve diameters in extreme preterm infants, based on BSA. Biological variation, inaccuracy in assessment of patient characteristics, inter-operator variability, and limited spatial resolution may account for substantial variability in heart valve diameters found in this cohort. Asymmetric lung perfusion in congenital heart disease: impact of differential pulmonary arterial anatomy and pulmonary vascular resistance O. Kondrachuk, T. Yalynska, R. Tammo, I. Iershova, N. Rokytska; Kiew/UA Purpose: Asymmetry of lung perfusion is relatively common in patients with congenital heart disease. The aim of the study was to evaluate the influence of differential pulmonary arterial anatomy and pulmonary vascular resistance on blood flow distribution in patients with asymmetric lung perfusion. We retrospectively identified 17 consecutive patients with congenital heart disease who had asymmetry of lung perfusion on phase-contrast MRI. The MRI examinations were performed on 1.5 T scanner. Results: Fourteen patients had left lung hypoperfusion (blood flow to the left lung < 35%) and three patients right lung hypoperfusion (blood flow to the right lung < 40%). Branch pulmonary artery (BPA) regurgitant fraction (RF) was significantly greater in lung with decreased perfusion (16.2±19.0% vs. 1.8±2.8%, P < 0.001). There was moderate negative correlation between BPA RF and BPA differential pulmonary blood flow (R = -0.517, P = 0.002). Moderate positive linear relationship between BPA size and BPA differential pulmonary blood flow was also found (R = 0.669, P = 0.003). There was no significant correlation between BPA RF and BPA size. Conclusion: Both BPA anatomy and BPA RF are the significant factors for determining right and left lung flow split. According to prior reports, BPA RF reflects differential pulmonary vascular resistance. consecutively at 80 kVp, 100 kVp, 120 kVp and 140 kVp, respectively, with constant mAs settings using a dual-source CT. Differences in calculated dual-energy ratios (DEratio) between the tissues and iodine or gold were determined for different DE spectra. The attenuation of gold has increased at higher kVp-settings compared to 80 kVp, while the attenuation of all other specimens decreased. The calculated DE ratios at 80/100 kVp, 80/120 kVp and 80/140 kVp, respectively, were 1.31, 1.63 and 1.91 for iodine, 0.90, 0.88 and 0.92 for gold, 1.20, 1.30 and 1.45 for compact bone, 1.01, 1.03 and 1.08 for muscle. The difference between the DE ratios 80/100 kVp, 80/120 kVp and 80/140 kVp, respectively, were 0.11, 0.23 and 0.46 for iodine and bone, 0.31, 0.51 and 0.53 for gold and bone, 0.29, 0.59 and 0.83 for iodine and muscle, 0.12, 0.15 and 0.16 for gold and muscle. Conclusion: DE ratio of gold remains relatively stable along the energy spectrum of diagnostic CT and allows a reliable material differentiation between gold and bone at contiguous low tube voltage settings (80 kV and 100 kV). Thus, gold might have potential as a contrast agent for DECT. Potential use of intra-articular diluted high-relaxivity gadoliniumbased contrast agent for magnetic resonance arthrography ( Purpose: Gadobenate dimeglumine (Gd-BOPTA) is a high-relaxivity contrast agent that tightly binds to plasmatic proteins, currently used in several clinical applications. Our aim was to test in-vitro different concentrations of Gd-BOPTA to be potentially used to perform MRA. Methods and Materials: Gd-BOPTA (Multihance, Bracco) was diluted in saline (NaCl 0.9%) to achieve different concentrations (4 mmol/l, 2 mmol/l, 1 mmol/l, 0.67 mmol/l, 0.5 mmol/l). Five mL of these solutions was injected in sterile pipes and was added with 0.5 mL of fresh synovial fluid withdrawn from a 71-year-old male knee. In a separate pipe (reference), 0.5 mL of synovial fluid and 5 mL of gadopentetate dimeglumine 2 mmol/l (Gd-DTPA; Magnevist) were injected. Pipes were imaged using a T1-weighted sequence (TE=9.8 msec, TR=678 msec, slice thickness 3.5 mm, FOV 320x320 mm) at 1.5 T. For each pipe on each slice, signal intensity (SI) was calculated. Results: Mean Gd-DTPA SI was 1290±48. Mean Gd-BOPTA SI was 1406±36 (+9% to reference) at 4 mmol/l; 1532±36 (+15%) at 2 mmol/l; 1583±36 (+19%) at 1 mmol/l; 1494±44 (+14%) at 0.67 mmol/l; 1235±13 (-4%) at 0.5 mmol/l (P <.001). At post hoc analysis, all one-to-one comparisons were significantly different with exception of 2 and 4 mmol/l (P=.105). Conclusion: Versus Gd-DTPA, a +19% peak SI was achieved with half Gd-BOPTA concentration. A similar SI between the two agents was achieved at 0.5 mmol/l. Gd-BOPTA high relaxivity and its potential binding with synovial fluid glycoproteins could explain these results. This may improve visibility of intra-articular tears when evaluated using Gd-BOPTA MRA. Purpose: To optimise the contrast injection protocol for CT coronary angiography (CTCA) to achieve more efficient utilisation of contrast agent by investigating the impact of reducing the volume of contrast agent on the attenuation of coronary arteries and sinus. Methods and Materials: A total of 105 subjects with low heart rate (² 65 beats/min) and suspected coronary artery disease were randomly divided into three groups with 35 subjects in each group. The patients in Groups A, B and C were injected with a volume of 0.8, 0.7, and 0.6 ml/kg of contrast agent, respectively. In all cases, injection rate was 5.0 ml/s, followed by 30 ml saline flush at the same rate. CT values within the ascending and descending aorta, left main and right coronary artery orifices and coronary sinus were measured and the differences of contrast enhancement among the three groups were evaluated. The mean injection volume of contrast agent in Groups A, B and C were 54.1, 47.9 and 41.1 ml, respectively (P < 0.001), and the scan delay time were 23.7, 23.4 and 22.2 s, respectively (P < 0.05). The CT values within the coronary sinus were 112.7, 93.7 and 81.2 HU for Groups A, B and C, respectively (P < 0.001), perience in paediatric pulmonary disease scored independently HRCT, using the scoring system developed by Helbich et al, and MRI using two scoring systems developed by Helbich et al and Eichinger et al. Readers were blinded to clinical and functional data and to the other reader's findings. The agreements were assessed using the intraclass correlation coefficient (ICC) and the Bland-Altman plot for the two readers and the two methods. The inter-reader agreement was excellent for the HRCT scores (ICC=96%), good for MRI with the Eichinger score (ICC=84%), but less for MRI with the Helbich score (ICC=68%). There was a very good correlation between HRCT and MRI-Eichinger scores (ICC=91%), but less between HRCT and MRI-Helbich scores (ICC=78%). The good inter-reader agreement and the high correlation between HRCT and MRI-Eichinger scores support the use of lung MRI for the follow-up of lung disease in paediatric CF patients. Methods and Materials: A total of 74 consecutive patients, with clinical vascular aortic disease, were evaluated on MDCT16 slices scan (Philips-Brilliance16P, NL) using low-kV protocol (90 kV), high pitch (1.063) and automated tube current modulation. Low contrast medium volume (50 mL) was administered at 4 ml/s. Density measurements were performed at abdominal aorta, renal arteries and common iliac arteries. We also calculated the radiation dose exposure (dose length product, DLP). Our results were compared with 40 patients investigated with standard contrast medium volume (100 mL) and standard CT-angiography protocol (120 kV; 350 mAs). The noise level (signal-to-noise ratio, SNR), the radiation dose (expressed as DLP) and amount of iodinate contrast were analysed and statistically compared between two different groups. Results: In all of the patients we obtained an adequate vessel opacification of aorta and renal arteries. Mean attenuation value in aorta was 305 HU, in iliac arteries was 288 HU and in renal arteries was 276 HU, without significant attenuation difference with the control group (aorta 339 HU; iliac arteries 358 HU; renal arteries 303 HU). The radiation dose exposure (meanDLP: 509) was significantly lower (reduction of the 48%) in the low-kV protocol than standard examinations at 120 kV (mean-DLP: 952). The noise level calculated in low-kV protocol (meanSNR 20) was not significantly higher than the value obtained in standard protocol (meanSNR 28). Conclusion: Low-dose CT-angiography protocol represents a feasible technique that allows a significant reduction of contrast material and radiation dose exposure without losing diagnostic accuracy being useful also in these patients with renal failure. Purpose: The use of low concentrated contrast material might be advantageous in terms of viscosity. Therefore, the purpose of this study was to evaluate the use of low concentrated contrast material (240 mg Iodine/ml) for coronary CT angiography in routine patients. Methods and Materials: 29 consecutive patients who were referred for routine coronary CTA were scanned on a 2 nd generation DSCT scanner (Definition Flash, Siemens). Patients received a standard contrast injection protocol as follows: Iopromide 240 mg/ml (Ultravist, Bayer) with an injection rate of 9 ml/s (iodine delivery rate 2.16 g I/s) followed by a saline chaser with the same flow rate. Contrast enhancement in the coronaries was measured proximal and distal in all coronaries. Results were compared to our standard protocol with Iopromide 300 mg/ml and flow rate of 7.2 ml/s (iodine delivery rate 2.16 g I/s). Start delay was evaluated for both groups using the test bolus method. Comparison between both groups was performed using sample t-test. Results: Coronary enhancement reached diagnostical attenuation in both protocols. Overall comparison between enhancement with 240 mg/ml (mean 445 HU ± 114 HU) revealed no statistical significant differences with 300 mg/ml (mean 412 HU ± 92 HU) (p=0.101). Attenuation levels in LAD dist and Cx dist were significantly higher in the low concentrated contrast material group (LAD dist 387 vs 292 HU, P < 0.0001 and Cx dist 392 vs 329 HU, P=0.003, respectively). Conclusion: The use of low concentrated contrast material is feasible in coronary CTA. Higher flow rates are necessary, but lower viscosity might improve attenuation in the distal segments. The impact of MR contrast agent concentration on bolus geometry G. Jost, H. Pietsch; Berlin/ DE (gregor.jost@bayer.com) Purpose: In contrast-enhanced MR-angiography, the luminogram is obtained during the first passage of gadolinium-based contrast agents (GBCA). The bolus concentration in conjunction with the r1-relaxivity determines the vascular signal enhancement. The aim was to investigate the impact of a 1 molar GBCA concentration on bolus geometry compared to a 0.5 molar agent, systematically. Methods and Materials: 6 Göttingen minipigs were injected intravenously with gadobutrol and Gd-DTPA in a crossover setting (0.1 mmol/kg, 1 ml/s). Dynamic CT measurements (80 kV, 485 mAseff, Δt=0.3s) at the thoracal region were performed without table feed. Time-density curves were determined and fitted by a gamma-variate function in the vena cava, the pulmonary artery and the ascending and descending aorta. CT-signals were transformed to Gd-concentrations on the basis of phantom measurements. The administration of 1 molar gadobutrol led to a narrower (significantly lower full width half maximum) and steeper (significantly higher peak values) bolus and CT values within the ascending and descending aorta, and the coronary artery were higher than 300 Hounsfield units in all three groups. Conclusion: Application of the 0.6 ml/kg protocol in CTCA, a steady contrast enhancement in coronary artery, can be achieved using 640-slice volume CT. The influence of the contrast media protocol and the scan mode on arterial enhancement in cardiac CT E. Talakic, D. Stocker, P. Täubl, R. Maderthaner, F. Quehenberger, H. Schoellnast, M. Tillich; Graz/ AT (emina.talakic@medunigraz.at) Purpose: To assess the influence of contrast media protocol and scan mode on arterial enhancement in cardiac CT. Methods and Materials: 175 patients (mean age, 62; range, 18-86 years) who underwent cardiac CT were retrospectively divided into 4 groups related to scan mode (64-slice helical CT or 320-slice volume CT) and contrast media concentration (320, 350 or 400 mgI/mL) -Group 1:, helical, 320 (75 mL); group 2: helical, 350 (90 mL); group 3: helical, 400 (70 mL), and group 4: volume, 400 (70 mL). Injection rate was 5 mL/sec in all patients. ROI measurements were performed in the aorta (coronary arteries level) and cardiac chambers to assess enhancement, and in the superior vena cava (SVC) to measure the standard deviation of the attenuation values for assessment of inflow artefacts. Spearman Correlation and Wilcoxon test were used for comparison. Results: Patients in group 3 showed significantly higher mean aortal enhancement than patients in group 1 or 2 (334 HU versus 286 HU and 306 HU). Group 4 showed significantly higher aortal enhancement than group 3 (497 HU). Group 4 showed significantly lower enhancement in the right atrium and ventricle than group 3. No significant difference in the standard deviation of attenuation was seen within the SVC. Conclusion: In cardiac CT, the volume mode led to significantly higher aortal enhancement and lower contrast within right atrium and ventricle compared with helical mode. Scan mode, iodine dose and flow rate had no influence on heterogeneity of contrast within the SVC. Multislice CT angiography with direct intra-arterial ultra-low-dosecontrast injection for the evaluation of renal graft failure: initial study M. Guzinski, J. Kurcz, J. Garcarek, M. Sasiadek; Wrocław/PL (guziol@wp.pl) Purpose: To present initial experience with direct intraarterial ultra-low-dosecontrast CT angiography (IA-CTA) and its application in assessing renal graft artery in patients with renal graft failure. Methods and Materials: IA-CTA of renal graft was performed in 18 patients with renal graft failure (GFR2m/s. Pig-tail catheter 4 F was placed in ipsilateral common iliac artery via common femoral artery. Subsequently, spiral CTA of pelvis was performed simultaneously to intraarterial administration at 4 ml/s of 6-8 ml of contrast diluted with saline to 18-24 ml. Results: Excellent contrast enhancement of renal graft arterial tree was observed in all patients. No complications associated with arterial access occurred. Mean creatinine/GRR levels prior to the IA-CTA were 3.30 mg/dl and 27.4 ml/min, respectively. On the 5 th day following the study, mean creatinine/GFR levels amounted to 3.36 mg/dl and 27.8 ml/min, respectively. Renal function deterioration was demonstrated on the 3 rd day after the procedure (creatinine 3.54 ml/dl, GFR 26.8 ml/min); nevertheless, it was not statistically relevant (p < 0.71). Contrast-induced nephropathy occurred in only one patient (5.6%) with transient creatinine elevation by 92%. After detailed vessel analysis graft arterial stenting was performed in 10 patients, which improved renal function. The remaining 8 patients were treated conservatively. Conclusion: Trans-catheter ultra-low-dose-contrast IA-CTA for imaging of renal graft arteries can be an effective method with low-risk of nephrotoxicity, which allows detailed graft arterial tree imaging, especially prior to interventional treatment of arterial-related renal graft insufficiency. Feasibility in low kV CT angiography of the abdominal aorta: assessment of image quality, radiation exposure and contrast material volume C.R.G.L. Talei Franzesi, D. Ippolito, P.A. Bonaffini, V. Bartolo, C. Trattenero, S. Sironi; Monza/IT (ctfdoc@hotmail.com) Purpose: To assess the image quality, dose reduction and amount of iodinate contrast injected using low-kV CT angiography protocol for the study of abdominal aorta disease. shape compared to 0.5 molar Gd-DTPA in all investigated vessels. The respective Gd-concentrations (mgGd/mL) for gadobutrol vs. Gd-DTPA were 9.5±1.9 vs. 6.8±1.2 (vena cava), 3.4±0.4 vs. 2.4±0.3 (pulmonary artery) and 2.2±0.2 vs. 1.7±0.2 (ascending and descending aorta). The area under the bolus curve analysis yielded no significant differences between the GBCAs. Conclusion: A 1 molar GBCA concentration leads to a more compact bolus shape with significant higher peak concentrations in the major thoracal vessels compared to a 0.5 molar agent. This might be especially relevant for the acquisition of 4D angiograms and for quantification of tissue perfusion. Author Disclosures: G. Jost: Employee; Bayer Pharma AG. H. Pietsch: Employee; Bayer Pharma AG. Transarterial chemoembolisation (TACE) in malignant liver metastases: evaluation of a fast C-arm CT acquisition protocol with a robotic multi-axis C-arm system T.J. Vogl 1 , M. von Roden 2 , E. Mbalisike 1 , S. Zangos 1 ; 1 Frankfurt a. Main/DE, 2 Forchheim/ DE (t.vogl@em.uni-frankfurt.de) Purpose: To evaluate potential contrast savings and reduction of motion artefacts in C-arm CT acquisitions with a higher rotational speed during interventional procedures. Methods and Materials: 24 patients (mean 56.8 yrs, range 33-83) were treated with transarterial chemoembolisation (TACE). Prior to the injection of the embolisation material, a C-arm CT with a new, fast acquisition protocol was performed. A robotic multi-axis C-arm angiographic system (Artis zeego, Siemens-Healthcare, Forchheim/Germany) was used with a rotational speed of up to 100°/s. In this configuration, a C-arm-CT with a rotational trajectory of 200° was acquired in 3s versus 5s in a commercially available C-arm system. Two different injection protocols were applied and evaluated regarding sufficient tumour visualisation and spatial resolution of the vessel tree in the resulting 3D-dataset. Results: Injection protocol 1 (6 ml contrast, 12 ml NaCl, flow rate 3 ml/s, x-ray delay 3s, injection site: common hepatic artery) resulted in 3D images with a very good spatial resolution of the vessel trees but poor visualisation of tumours/metastases. Injection protocol 2 (7 ml contrast, 20 ml NAaCl, x-ray delay 6s) resulted in 3D images with excellent spatial resolution and good visualisation of tumours/ metastases. From prior experience with a standard 5s protocol the corresponding C-arm CT acquisition would have required a contrast load of 8 ml and 8.5 ml, respectively. Thus, the contrast saving of the fast acquisition protocol was 25% and 18%, respectively. The fast C-arm CT acquisition protocol 2 provides an interesting possibility to save contrast media during TACE with excellent spatial resolution of the vessel tree and good visualisation of hypovascular tumours. Purpose: Functional MRI of cerebrovascular reserve (CVR fMRI) using vasoreactivity to hypercapnia may identify patients at risk of haemodynamical stroke among those with severe stenosis of the middle cerebral artery (MCA). However, quantification remains challenging because of numerous methodological settings and their limitations. We aimed to provide a laterality index (LIMCA) to better identify abnormal CVR in clinical practice. Methods and Materials: 100 volunteers (40 females; 49.5±21.4 years) without cervico-encephalic arterial stenosis had a CVR fMRI using BOLD contrast with a block-design hypercapnic challenge (CO2 7% mixed with: O2 93% (n=83) or air (n=17)), using nasal canula (n=57) or mask (n=43), 1.5 T (n=46) or 3 T (n=54). Averaged end-tidal CO2 pressure (EtCO2) was used as a physiological regressor for statistical analyses with a general linear model (SPM8). We conducted regions of interest (ROI) measures of %BOLD signal change/mmHg EtCO2 on segmented grey matter of the MCA territories. We calculated a laterality index with LIMCA=(Left_CVRMCA-Right_ CVRMCA)/(Left_ CVRMCA +Right_ CVRMCA). 99% confidence intervals (99%CI) were calculated. No adverse reaction to hypercapnia, including panic, anxiety, headache, or fatigue, was detected during and after CVR fMRI. CVR values ranged from 0.14 to 0.48 with m±sd=0.26±0.07 %BOLD/mmHg EtCO2. The mean laterality index was 0.01 with an interval of fluctuation that covered 0.00. The standard deviation was 0.026. Thus, 99%CI was ±0.07 for MCA. LI values were independent of age, gas mixture, sex, inhalation modality, and MR strength. Conclusion: Subjects without cervico-encephalic arterial stenosis have an absolute value of LIMCA below 0.08 with a 99% probability. In Purpose: Non-invasive quantitative phase contrast MR angiography (qMRA) has been utilised for several clinical indications, e.g. intracranial stenosis and aneurysms. The aim of this study is to validate the flow measurements of qMRA (NOVA, VasSol Inc., Chicago) by comparing the obtained velocities with qMRA and Doppler ultrasonography (DUS) in-vivo. To our knowledge, no previous reports have addressed this issue. Methods and Materials: We retrospectively examined consecutive 24 patients (9 women, 15 men; mean age 63 years, range 24-80 years) with stenosis of arteries supplying the brain using qMRA and DUS. Velocities were measured in a total of 209 arterial segments (110 extra-and 99 intracranial). Results: Overall there was a good correlation between velocity measurements with both techniques being statistically significant in all six extracranial and five out of seven intracranial segments. Velocities were 56% higher in extracranial and 45% higher in intracranial segments obtained with DUS comparing to those with qMRA. The reversal of flow direction in the ACA was detected consistently with both methods. Conclusion: This preliminary study shows a rather good correlation between the velocities employed with qMRA and DUS. QMRA represents a robust MRI technique for flow measurements in a reasonable time, which can be integrated in the cerebrovascular MRI work-up, especially when intracranial DUS is technically not feasible. However, further in-vivo and in-vitro studies are needed to assess the need for technical optimisation of this technique. Purpose: Sensitive documentation of ischaemia is needed in clinical TIA. We aimed to compare the sensitivity of DTI, DWI and ASL in the detection of acute ischaemia and further to investigate if chronic ischaemic changes after 8 weeks in the form of gliosis always follow. Methods and Materials: The first 40 consecutive patients included during first 3 months of an MRI-protocol (DWI, DTI and ASL within 72 hours of symptoms) and 8 weeks follow-up protocol (T2 and DWI). Patients were included by stroke consultants. Lesion volumes on DWI, DTI and follow-up T2 were compared. Hyper-or hypoperfusion on ASL was recorded. One senior neuroradiologist assessed the sequences in random order to prevent bias. Results: Fourteen patients had acute ischaemic lesions: 2 in the posterior fossa and 12 in the cerebral hemispheres corresponding to 35% of referred patients. Thirteen of these developed gliosis in the affected area and of these 1 was noted only on DTI and 1 only as post-ischaemic hyper-perfusion on ASL. Mean lesion volume was 1.2 mL. Mean difference between volume on DWI and gliose volume was 0.42 mL =71% and between DTI and gliose volume 0.29 mL=40% and DTI volume were significantly closer (p=0.042). Conclusion: These preliminary results indicate that TIA causes a gliosis lesion consistently, and that the initial lesion as well as the extent of the permanent changes is better described using DTI. ASL seems to be able to contribute to the detection of TIA as this may be sole MRI-sign in some patients increasing detection rates with 5%. Monday parameter for assessment of ischaemia. We analysed the ability of TTP maps to predict eventual infarcts in patients with mild stroke presentations. We retrospectively reviewed 164 consecutive patients presenting with acute stroke in less than 6 hours from onset. Patients presenting with a NIH Stroke Scale Score < 5 were subjected to subgroup analysis. TTP perfusion deficit with delays of more than 3 seconds was considered significant for underlying ischaemia. The perfusion parameters were compared to follow-up imaging at 24 to 48 hours. Results: 41 patients met inclusion criteria. 7 patients had identifiable thrombus. The TTP map had the highest sensitivity in detecting the small infarcts (92%), followed by CBV and CBF. Importantly, TTP analysis provided very high negative predictive value (93%). However, there was a relatively lower specificity (64%) and a tendency to overestimate the infarct size. Conclusion: TTP perfusion is highly sensitive in predicting small regions of ischaemia. High negative predictive value is helpful in differentiating stroke from mimics. Purpose: To study the influence of the temporal sampling rate of CTP acquisitions on cerebral perfusion maps with noise-free synthetic data sets created with a digital phantom. Methods and Materials: Noise-free synthetic data sets were created with a digital phantom which consists of a skull derived from a human skull phantom combined with arterial input and venous output functions, white matter (WM) and grey matter (GM) time-attenuation curves (TAC) obtained from 5 patients. By manipulating the time tags CTP protocols with a total scan duration of 60s and a temporal sampling rate of 1-, 2-, 3-and 4s were simulated. The 1-s protocol was used as reference standard. The 2-, 3-and 4-s protocols were shifted with 1s to measure the influence of missing peak points of the curve, resulting in 1, 2, 3 extra data sets, respectively. CBF, CBV and MTT maps were calculated using PMA (ASIST-Japan). Mean values of GM and WM of the protocols were compared with the reference protocol. DE (kolja.thierfelder@med.uni-muenchen.de) Purpose: Our aim was to evaluate if the extent of volumetrically determined blood flow-volume mismatch in recently introduced whole brain CT perfusion (WB-CTP) can predict if a stroke is younger than 4.5 hours (time window for thrombolysis). We retrospectively analysed cerebral blood flow (CBF) and volume (CBV) maps and clinical data of 103 acute stroke patients. CT perfusion images were acquired with extended brain coverage of 10 cm in the z-axis. Mismatch extent was defined as the fraction of CBF perfusion deficit without corresponding CBV abnormality and was determined volumetrically using Osirix V.4.0 imaging software. A logistic regression analysis was performed to predict time from symptom onset of < 4.5 hours. Four mismatch extent categories, CBF perfusion deficit and CBV infarction volume were entered as predictors into the model. Results: Mean time from symptom onset was 187 min±101 min. Mean mismatch extent was 59.5%±31.1%. After correcting for age and gender, a mismatch extent of ³90% was highly predictive for a symptom onset of < 4.5hrs (n=18, OR: 8.70, p=0.03). Other categories of mismatch extend (³80% (OR: 6.67, n=31, p=0.10), < 10% (n=13, OR: 0.90, p=0.89), < 20% (n=19, OR: 1.36, p=0.66) as well as CBF perfusion deficit volume (p=0.86) and CBV infarction volume (p=0.77) failed to predict time from symptom onset. Conclusion: A large (³90%) volumetrically determined mismatch in WB-CTP is a predictor for the time from symptom onset in the critical time window. WB-CTP mismatch might, in these cases, help to identify patients eligible for thrombolysis when symptom onset is unknown (e.g. wake up stroke). Whole brain CT perfusion: volumetric assessment of perfusion deficits in patients with acute ischemic stroke K.M. Thierfelder 1 , L. Purpose: Whole brain CT perfusion (WB-CTP) eliminates the major drawback of restricted brain coverage in standard 2-slice CTP. Our aim was to assess reliability and reproducibility of a newly introduced volumetric assessment method of perfusion deficits in WB-CTP in patients with acute ischemic stroke. Methods and Materials: 24 consecutive patients underwent 128-row WB-CTP with extended scan coverage of 10.0 cm in the z-axis using adaptive spiral scanning technique. Volumetric analysis of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), time to peak (TTP), and time to drain (TTD) was performed twice by two experienced readers using dedicated imaging software with at least 2-week intervals between readings. Inter-and intrareader agreement for individual perfusion parameter maps was assessed by intraclass correlation coefficients (ICC) and Bland-Altman analysis. Results: Interreader agreement was highest for TTD (ICC: 0.985), followed by CBF (0.969), MTT (0.949), CBV (0.935), and TTP (0.851). Intrareader agreement was also highest for TTD (ICC: 0.995), followed by MTT (0.979), CBF (0.977), CBV (9.942), and TTP (0.944). The perfusion deficits showed the highest absolute mean volume in the time-related parametric maps and did not differ significantly within this group, while mean CBF perfusion deficit volume was significantly smaller (each with p < 0.01). Conclusion: Volumetric assessment in WB-CTP in acute stroke patients is reliable and reproducible. It therefore might serve for a more accurate assessment of prognosis of stroke outcome and definition of flow-volume mismatch. TTD had the highest agreement and therefore might be a suitable parameter to define tissue at risk. Time-to-peak (TTP) maps using whole brain CT perfusion in minor stroke: a diagnostic tool beyond penumbra measurement S. Chakraborty, M.E. Ahmad, J.K. Wasserman, K. Keyhanian, D. Dowlatshahi, G. Stotts; Ottawa, ON/CA (santanoo@gmail.com) Purpose: The use of thrombolysis in minor stroke or fluctuating symptoms is controversial. Treatment decisions may be influenced by identifying patients with large areas of tissue at risk and distinguishing stroke mimic. Whole brain CT perfusion in Toshiba 320 Aquilon® CT scanner allows possible assessment of these parameters and is not limited to selective brain coverage as in previous generations of CT scanners. Dynamic chest x-ray examination for regional ventilation function must be equivalent to lung scintigraphy. Performance evaluation of automatic chest radiograph reading for detection of tuberculosis (TB): a comparative study with clinical officers and certified readers on TB suspects in sub-Saharan Africa P. Maduskar 1 , L. Hogeweg 1 , B. van Ginneken 1 , H. Ayles 2 ; 1 Nijmegen/NL, 2 London/UK (p.maduskar@rad.umcn.nl) Purpose: Digital chest radiography (CXR) is used in high burden countries for suspect screening, active case finding and in prevalence surveys for TB diagnosis. An observer study was conducted to compare performance of automatic software with that of clinical officers and certified expert readers. A dataset of 166 digital CXRs (2048×2048, 0.25 mm, Delft Imaging Systems, The Netherlands) was collected at Kanyama Clinic, Lusaka, Zambia. Sputum culture was used as reference. An observer study was conducted with four clinical officers who read x-rays in Kanyama Clinic, and with two readers certified to read CXRs according to CRRS standard (University of Cape Town, South Africa). A software system for detection of TB (CAD4TB-1.08, Diagnostic Image Analysis Group, The Netherlands) analysed all the cases. Human readers and software scored all the images between 0 and 100. We report area under the receiver operating characteristics curve (Az) with 95% confidence intervals and pairwise comparisons from bootstrap estimates. p < 0.05 was considered significant. There was no significant difference between any reader and the software, except for one clinical officer who performed significantly worse than automatic reading. Conclusion: Automatic computer reading has similar performance as clinical officers and certified readers. The software has potential of being used as a point-of-care decision tool, to diagnose TB or select subjects that should undergo further tests. Diagnostic imaging costs before and after digital tomosynthesis implementation in patient management after suspected thoracic lesions on chest radiography E. Quaia, E. Baratella, G. Grisi, R. Cuttin, G. Poillucci, S. Kus, M. Cova; Purpose: To evaluate diagnostic imaging costs before and after digital tomosynthesis (DTS) implementation in patients with suspected thoracic lesions on chest radiography (CXR). Over a period of four years four-hundred-and-sixty-five patients (263 males, 202 females; age, 72.47±11.33 years) with suspected thoracic lesion (s) after CXR underwent DTS. Two readers prospectively analysed in consensus DTS images. Each patient underwent CT when a pulmonary non-calcified lesion was identified by DTS, while CT was not performed when a benign pulmonary or extrapulmonary lesion or pseudolesion was identified. Diagnostic imaging costs (including material, staff, and imaging system depreciation) were evaluated during the12-month preceding DTS implementation and during the12-month after DTS implementation. The average imaging cost per patient was calculated by normalising the costs before and after implementation of DTS by the number of indeterminate CXR examinations in each of these periods. Results: In 229/465 patients who underwent DTS after suspicious CXR, DTS showed 193 thoracic lesions and 36 pleural lesions, while in the remaining 236/465 patients lesions were ruled-out as pseudolesions of CXR. In the 12-month preceding DTS implementation, the proportion of patients who presented suspected thoracic lesions and underwent CT was 271/811; after DTS implementation, this proportion became 39/800. The average differential per-patient costs of CXR, DTS, and CT examinations were 15.15, 41.55, and 113.66 euros, respectively. The perpatient change in diagnostic imaging costs before vs after DTS implementation was -24.79 euros. Conclusion: Per-patient diagnostic imaging costs decreased after DTS implementation in patients with suspected thoracic lesions. within each cross-sectional image the mean (ADCmean), minimum (ADCmin) and maximum ADC (ADCmax) was determined by two independent radiologists. An additional ROI was placed into the cerebrospinal liquid and set as the reference tissue. Statistical analysis included the Wilcoxon test and p-values < 0.05 indicated statistical significance. Results: The highest ADC values were determined for the group of adenocarcinomas (ADCmean, 1.98x10-3 mm2/s; ADCmax, 2.44x10-3 mm2/s). Significantly lower mean ADCs were found for the squamous cell carcinomas (ADCmean, 1.18x10-3 mm2/s; p < 0.0001) and small cell lung cancers (ADCmean, 1.29x10-3 mm2/s; p=0.01). Determination of the ADC values did not reveal any difference between squamous cell and small cell carcinomas (p> 0.05). Conclusion: Diffusion-weighted MRI with ADC measurement at 1.5 T reliably enables the differentiation of adenocarcinoma from other histological subtypes in primary lung cancer and might therefore be of distinct value in the preoperative management of patients suffering from primary lung cancer. Non-contrast-enhanced perfusion MRI for preoperative assessment of lung function in patients with non-small-cell lung cancer ( Purpose: Knowledge about lung function defects is important for predicting functional outcome and optimising surgery in NSCLC. Fourier decomposition MRI (FD-MRI) has been introduced as a method to assess regional lung perfusion without contrast agents. This study evaluates FD-MRI for preoperative assessment of lung perfusion in NSCLC patients with dynamic contrast-enhanced MRI (DCE-MRI) as standard of reference. Methods and Materials: 15 patients with NSCLC were examined at 1.5 T. Timeresolved images of the lungs were acquired in coronal and sagittal plane using a 2D-bSSFP sequence. Fourier decomposition was used to detect and separate periodic changes of lung proton density caused by respiratory and cardiac cycles. Perfusion-weighted images were calculated by pixel-wise integration of the cardiac spectral line. FD and DCE data were analysed visually for perfusion defects. Perfusion proportions of pulmonary lobes were calculated quantitatively by regions-of-interest analyses. Results: FD-MRI provided diagnostic quality in 14 cases, but failed in one patient. Sensitivity, specificity and accuracy of FD-MRI for visual detection of perfusion defects were 78%, 92%, and 90%. Quantitative evaluation of perfusion proportions provided good linear correlation between FD-MRI and DCE-MRI for both upper lobes and both entire lungs (r=0.70-0.85). Accuracy of FD-MRI in the lower lobes (r=0.02-0.03) and the middle lobe (r=0.32) was compromised by artefacts from cardiac pulsation. Conclusion: FD-MRI is useful to detect regional lung perfusion defects in NSCLC patients before surgery. For perfusion quantification, FD-MRI is sufficiently accurate in both upper lobes and for bilateral comparison, but, in its present form, inaccurate in the middle lobe and both lower lobes. Lung ultrasound in the elderly population: investigating the limit between physiological and pathological patterns A. Chiesa, F. Ciccarese, G. Gardelli, F. Feletti, U. Regina, M. Zompatori; Bologna/IT (ciccarese.f@gmail.com) Purpose: The senile lung undergoes paraphysiological changes which have been described in several radiological and CT studies, but never investigated through ultrasound. The aim of the present study was to evaluate a group of elderly-nonsmoker-healthy patients in comparison with young subjects, by using ultrasound examination. Methods and Materials: 100 elderly subjects (> 70years-mean age: 79.4±6.9) and 50 young subjects (< 55years-mean age: 32.5±12.1) were submitted to lung ultrasound examination. We analysed the anterior, lateral and posterior surface of each lung to evaluate the presence/absence of A-lines and B-lines. Fisher test was chosen to compare data obtained in the two groups. Results: Absence of A-lines was found in 94/100-94.0% of elderly versus 2/50-4.0% of young subjects (p < 0.0001). Presence of B-lines was detected in 37/100-37.0% of elderly, with a higher prevalence in posterior lung fields; the number of B-lines was²3 per field (pf) in 27/37-73.0%, > 3pf in 2/37-5.4%; both ²3 and > 3pf-depending on the evaluated field in 8/37-21.6%. By contrast, 5/50-10.0% young subjects showed B-lines (²3pf in all of cases)-p=0.0004. To avoid misdiagnosis, we should consider that physiological ultrasound lung findings could be different among old and young people. The majority of old individuals did not present A-lines; moreover in a high percentage, B-lines were observed (²3pf in most of them). These results could be explained by a reduction of impedance between lung parenchyma and soft tissue (absence of A-lines) and by an increased thickness of interlobular septa (presence of B-lines). Further studies should be proposed to define a cut-off between normal and pathological pattern. Digital x-ray optical densitometry in assessment of respiratory function in patients with COPD exacerbation N. Gorbunov, V. Laptev; Novosibirsk/RU (n_gorbunov@hotmail.com) Purpose: To evaluate respiratory function in patients with exacerbation of chronic obstructive pulmonary disease (COPD) before and after treatment by means of a digital x-ray optical densitometry. The study group comprised 563 patients (140 females, 423 males; mean age 58±1.3 years, range 36-81 years). All of them were admitted to the clinic with an exacerbation of COPD with different (1-3) stage. High-resolution digital radiographic device with a line x-ray sensitive silicate receiver was used. Lowdose digital x-ray examination of the chest was performed both in inspiration and in expiration phases before and after treatment. Regional and common pulmonary optical density was evaluated with further quantitative analysis of respiratory function. For these purposes the optical density gradient (ODG) was used. All results were verified by high-resolution computed tomography (HRCT). The optical density gradient before and after treatment has been changed. There was a 1.5-1.6 times increasing value of optical density gradient due to treatment of COPD exacerbation. For patients with the first stage of COPD the 64.7% ODG increasing was estimated. For the second stage of COPD ODG increasing was 63.1% and for the third stage of COPD it was 52.1%. There was a significant correlation between pulmonary optical density gradient and HRCT density gradient before and after treatment (r> 0.3; p < 0.05). A digital x-ray optical densitometry by means of functional highresolution digital radiography allows optimising an evaluation of therapy response in patients with COPD exacerbation combined with radiation exposure reduction. Diffusion Purpose: Despite the improvement in technique/expertise, pancreatic surgery remains burdened with a high complication rate. Our aim was to report our 12year single-centre experience about the clinical relevance and the interventionalradiological management of the early postoperative complications (treatment/ prevention) on 1285 patients submitted to pancreatic surgery. In 2000-2012, 1285 patients were submitted to pancreatic surgery (duodenum-cephalopancreatectomy, total-pancreatectomy, distal-pancreatectomy). Patients were classified on the basis of the complication severity into 5 classes (Clavien-Dindo-classification): class-0=none, class-1/2=conservative treatment, class-3a=endoscopic/interventional-radiological, class-3b=surgery, class-4=intensive care, class-5=death. Interventional-radiological management was as follows: PTC/biliary-drainage in case of biliary-fistulas (bile in surgical drainage, normal bilirubin levels, undilated biliary ducts at US) under US/fluoroscopic-guidance (right approach, puncturing along the course of the sixth-segment portal branch with 21G Chiba-needle, or left approach if aerobilia/ adequate volume of left hepatic lobe); embolisation (microcoils/PVA-particles) or covered-stenting (Viabahn-Gore) in case of bleedings of gastroduodenal/splenic arteries; percutaneous drainage (US/CT-guidance) of liquid/infected collections. Pancreatic-islet-intraportal-autotransplantation was performed in case of totalpancreatectomy to prevent diabetes. Results: Patients were classified as follows: 524/1285 (40%) class-0, 210/1285 (16%) class-1, 361/1285 (28%) class-2, 72/1285 (6%) class-3a, 55/1285 (4%) class-3b, 24/1285 (2%) class-4, 39/1285 (3%) class-5. 72/1285 (class-3a) and were successfully treated as follows: 30/72 PTC/biliary-drainages, 27/72 liquid/infected collection percutaneous-drainages, 9/72 bleedings (7 embolisations, 2 coveredstenting), 6/72 endoscopic-procedures. 25/1285 underwent pancreatic-isletintraportal-autotransplantation. One bleeding/1 biliary-fistula needed 2 treatments. Conclusion: In experienced centres of pancreatic surgery, complication rate can be reduced. Complications can be, however, successfully diagnosed, managed and prevented by interventional-radiological procedures, limiting their clinical relevance and avoiding a high-risk surgical re-treatment. Purpose: To evaluate technical feasibility and clinical efficacy of retrievable covered stents in treating post-surgical biliary leakage. Methods and Materials: From April 2008 to date, 16 patients (9 males, 7 females; mean age 52 years, range 18-83 years) were retrospectively studied. Patients underwent placement of retrievable covered stents for treat post-surgical bile leaks. In 12 cases the procedure was performed by interventional radiologist using percutaneous trans hepatic access and in 4 cases by means of hybrid procedure (PTBD + ERCP) with both interventional radiologist and endoscopist. The leaks involved cystic duct stump (n = 6), common bile duct anastomosis (n = 6), left extra hepatic duct (n = 1), right extra hepatic duct (n =2) and biliary confluence (n = 1). Results: Technical success with correct stent releasing was achieved in 15 cases; 1 case required post-dilatation ballooning. Immediate clinical and lab test improvements were observed in all patients. Post-operative imaging proved leak resolution in all cases. No early complications were observed. In 1 case late stent migration was reported 21 days after the procedure. Twelve stents were removed without complication after a mean time of 59 days, with complete leak resolution. One stent Comparison of assessment of preoperative pulmonary vasculature in non-small cell lung cancer patients by non-contrast-enhanced and 4D contrast-enhanced MR angiography at 3 T and by contrastenhanced thin-section MDCT using a 64-detector row system Y. Ohno 1 , S. Seki 1 , M. Nishio 1 , H. Koyama 1 , T. Yoshikawa 1 , S. Matsumoto 1 , S. Satou 2 , K. Sugimura 1 ; 1 Kobe/JP, 2 Ohtawara/JP (yosirad@kobe-u.ac.jp) Purpose: To prospectively and directly compare pulmonary vasculature assessment before surgical treatment of non-small cell lung cancer (NSCLC) patients by non-contrast-enhanced (non-CE) MR angiography, 4D CE-MR angiography and thin-section CE-CT. Methods and Materials: A total of 77 consecutive pathologically proven and clinically assessed stage I NSCLC patients (41 males, 36 females; mean age: 71 years) underwent thin-section CE-CT, non-CE-MR angiography and CE-MR angiography, and surgical treatment. The capability for anomaly assessment of the three methods was independently evaluated by two reviewers using a 5-point visual scoring systems, and final assessment for each patient was made by consensus of the two readers. Interobserver agreements for pulmonary arterial and venous assessment were evaluated with the kappa statistic. Assessment of variations in overall pulmonary vasculature by the three methods was compared by means of receiver operating characteristic analyses on a per-patient basis. Finally, sensitivity, specificity and accuracy for detection of anomalies were directly compared among the three methods by means of McNemar's test. Results: Interobserver agreements for pulmonary artery and vein assessment were substantial or almost perfect (0.72²κ²0.86). For pulmonary arterial and venous variation assessment, non-CE-MR angiography, 4D CE-MR angiography and thinsection CE-CT showed no significant differences (p> 0.05) in terms of area under the curve, sensitivity, specificity and accuracy. Conclusion: Pulmonary vascular assessment of NSCLC patients before surgical resection by non-CE-MR angiography can be considered equal to that by 4D CE-MR angiography and thin-section CE-CT. In vivo micro-CT and 18 F-FDG micro-PET imaging of SPC-raf and SPC-myc transgenic mouse models of lung adenocarcinoma T. Rodt, C. von Falck, M. Luepke, K. Hueper, R. Halter, S. Dettmer, C. Boehm, J. Borlak, F. Wacker; Hannover/DE (rodt.thomas@mh-hannover.de) Purpose: To report on micro-CT and micro-PET imaging of spontaneously developing lung tumour in SPC-raf and SPC-myc transgenic mice. Technical considerations regarding periprocedural management and imaging technique are addressed; tumour quantification techniques are presented. Dosage measurements are reported and potential adverse effects discussed. Methods and Materials: 4 wild-type control, 25 SPC-raf and 7 SPC-myc transgenic mice were examined in vivo using micro-CT (n=180) and 18 F-FDG micro-PET (n=14). Specific periprocedural management was established. Different respiratory gated and ungated micro-CT protocols were compared. A quantification routine for tumour load and growth was validated and examined in a follow-up study. 18 F-FDG micro-PET of orthotopic lung tumour was obtained; quantification was performed on lesion and lung region basis. Findings were correlated to histology. Thermoluminescence dosemeter measurements and dosage calculations for micro-CT and micro-PET were performed. Results: No procedure-related deaths occurred for up to 547 days of follow-up. Respiratory gated micro-CT protocols yielded better image quality compared with ungated protocols. Intra-and inter-observer variability of the quantification routine were 5.1 and 6.5%, respectively. Tumour quantification showed significant difference (p=0.043) between SPC-raf transgenic and control animals in follow-up. Longitudinal tumour development correlated to cross-sectional histological data from literature. Micro-PET yielded a tumour-to-non-tumour ratio of 2.47 in SPC-myc transgenic animals. Micro-CT dosage ranged from 174 to 277 mGy. The estimated dosage calculated for micro-PET was 140 mGy. Conclusion: Micro-CT and 18 F-FDG micro-PET provide quantitative data on morphology and metabolism in orthotopic lung tumour. The techniques can safely be applied in animal model phenotyping and therapeutic studies. Monday pancreatic cancer). 10 Watts for 2 minutes was applied using bipolar endoluminal RF device (Habib™ EndoHPB, EMcision Ltd., London, UK), placed in a block using guidewire technique. RFA is followed by self-expanding or balloon-mounted metal-stent (MS) placement. Drainage catheter was repositioned for follow-up. Results: Duct patency restorated in 34 (97.1%) cases; in 1 (2.9%) case procedure filed because of guidewire conduction failure. All cases of balloonoplasty required the repeated procedure followed by stenting. 34 biliary patients maintained stent patency as long as they are alive. The mean stent patency was 115.9 ± 64.8 (50 -240) days. There was no 30-day mortality, haemorrhage or pancreatitis following RFA. One complication (bile duct perforation) was observed in a post-balloonoplasty patient on repeated (RFA&Stenting) procedure; this case was managed percutaneally. Percutaneous RFA treatment appears to be safe and effective in the management of inoperable biliary and Wirsung duct block. Randomised studies with prolonged follow-up are warranted. Conclusion: VIATORR plays an important role in TIPS scenario but its outcomes are strictly related to technical aspects such as intrahepatic tract completely covered, no concern about liver transplant, device never advanced in the portal vein for more than 3 cm, 10-mm VIATORR has to be considered the best compromise. was removed 4 days after the procedure, during an open re-do for intra-abdominal bleeding. Three stents are still in place. Conclusion: Placement and removal of retrievable covered stents appear to be technically feasible and could represent an excellent option in treating biliary disorders. Bioabsorbable biliary stent in the percutaneous treatment of benign biliary stricture: preliminary experience G. Mauri, C. Michelozzi, V. Pedicini, D. Poretti, M. Tramarin, F. Melchiorre, G. Cornalba, G. Brambilla; Milan/IT (vanni.mauri@gmail.com) Purpose: To report the outcome of patients treated with a novel bioabsorbable biliary stent for benign biliary strictures. Methods and Materials: Ten bioabsorbable polydioxanone biliary stents (Ella-DV biliary stent, ELLA-CS, Czech Republic) were deployed in 9 patients with increased level of bilirubin due to postsurgical benign biliary stricture. This stent is made of polydioxanone, a material that allows to obtain a high radial force, but that is reabsorbed by the body within 6 months. All patients had stricture recurrence after multiple standard bilioplasty (2 to 5). All patients were followed with clinical visit, ultrasound and serum bilirubin level. The procedure was successfully performed in all patients and immediate restoration of the normal caliber of the biliary duct was obtained. No immediate or late complications occurred and no patients had recurrence of the initial stricture (median follow-up 13 months, range 5-18 months). Conclusion: Percutaneous bioabsorbable biliary stent placement is feasible and effective in the treatment of benign biliary strictures and in which standard bilioplasty has failed. In the future, this novel treatment may replace percutaneous bilioplasty a retrievable biliary stent placement as soon as long-term follow-up data will be available. To have a Y-configuration for the biliary drainage of both lobes of liver, we used two pieces of covered stent system: one covered main piece stent and one contra-lateral covered stent. Before and 3 days after Y-covered stent insertion, cholangiograms were obtained through the IHD for the evaluation of biliary drainage of both lobes of liver. We checked the blood bilirubin levels before, 1 week after and every 1 month after the stenting. Results: They were 16 patients including 12 women and 4 men. They had inoperable intrahepatic cholangiocarcinomas in 15 and two metastatic biliary obstructions due to breast and stomach cancers. Obstructive types were 2 in I, 7 in II, 5 in IIIa and 2 in IV. The placement of the Y-shaped covered stent was successful in all cases. The mean follow-up period was about 6 months. All cases had showed adequate biliary drainages in the follow-up tubograms. The bilirubin levels had been normalised 2 weeks after being the Y-covered stent inserted except one patient. There were no clinical infectious signs during the follow-up period. Mean patency rate was about 6.2 months (185 days). A newly designed Y-shaped covered stent would be clinically effective for the palliative treatment of hilar obstructive malignant carcinoma of liver. The comparison of balloon-occluded retrograde transvenous obliteration for gastric varices using liquid and foam sclerosants J. Koizumi 1 , K. Myojin 1 , C. Itou 1 , N. Mori 1 , T. Sekiguchi 1 , T. Hara 1 , T. Ichikawa 1 , Y. Imai 1 , B. Janne d'Othée 2 ; 1 Isehara/JP, 2 Baltimore, MD/US (jkoizumi@is.icc.u-tokai.ac.jp) Purpose: Liquid ethanolamine oleate which has been used traditionally for balloonoccluded retrograde transvenous obliteration (BRTO) of the gastric varices (GV) may cause severe complications including haemolysis, allergy, etc. if overdosed. Thus, we introduced foam sclerotherapy to reduce the dose and compared the safety and efficacy of BRTO using liquid and foam sclerosants. Methods and Materials: Forty-three patients with gastric varices were performed BRTO since October '01. Of these, three patients were excluded because simultaneous TACE or PSE was performed. Twenty patients using liquid ethanolamine oleate with iodine contrast (EOI) before March '05 and twenty patients using polidocanol foam (POF) after May '05 were included in this study. The success rates, side effects and complication rates were compared among the two groups. Results: Complete stasis of the gastric varices was obtained in all patients of both groups. Abdominal symptoms during BRTO were significantly (p < 0.05) higher in EOI (55%) than POF (15%). Postprocedure fever (> 38.0) was also significantly (p < 0.01) higher in EOI (55%) than in POF (0%). In both groups total bilirubin increased and platelet counts decreased significantly (p < 0.01). However, the decrease ratio of platelet counts was significantly (p < 0.05) higher in EOI (-21.1±15.8%) than POF (-9.4±13.1% Purpose: Digital linear tomosynthesis has recently been introduced not only for mammography but also for chest and musculoskeletal indications. The clinical utility in musculoskeletal applications has been validated in only a few reports. The purpose of the current study was to evaluate the clinical utility of tomosynthesis in suspect occult hip fracture. In a retrospective review 70 tomosynthesis hip examinations on 49 women and 21 men performed for further evaluation of suspect hip fracture were retrieved from the radiology archive. Three observers scored the tomosynthesis scans separately from the radiography examinations, into the categories no proximal femur fracture, suspect proximal femur fracture (femoral neck, trochanteric, or greater trochanteric avulsion) or definite proximal femur fracture. CT, MRI or clinical outcome was used as reference. Results: Observer variation was moderate to substantial for three observer pairs regarding radiography (k=0.56-0.8) and improved to substantial to almost perfect for tomosynthesis (k=0.76-0.93). Eleven patients were operated on for femoral neck fracture. Tomosynthesis detected ten of these, and the eleventh patient was operated on without diagnostic confirmation from any imaging modality. One patient had been operated with dynamic hip screw for intertrochanteric fracture. The remaining trochanteric fractures were incomplete and were treated conservatively. There were no false-positive tomosynthesis diagnoses reported. There were no significant falsenegative tomosynthesis diagnoses. The distinction between incomplete/complete trochanteric fractures and greater trochanteric avulsions is sometimes difficult. Purpose: Advanced core decompression (ACD) is in clinical evaluation for patients with avascular necrosis (AVN) of the hip. In opposition to standard core decompression, ACD uses an expandable reamer allowing optimal debridement of necrosis after drilling a core to the femoral head. The bone defect is filled with a bone graft substitute. We aimed to constitute the therapeutic success of ACD based on MRI. Methods and Materials: Twenty patients (17 males, 3 females, mean age 49.9 years) underwent 3 T MRI of the hip prior to, 30 days and 0.5 -2 years after ACD. The protocol included TIRM, PD/T2w TSE, high-resolution T1w, DESS and T1w VIBE sequences. Sequences were evaluated regarding delineation of necrosis, bone, graft and transformation zone in between. The volume of necrosis was measured before and after ACD. Results: AVN prior to ACD as well as the defect filled with the graft after ACD and the residual necrosis could be imaged with reproducible high quality at 3 T. T1w and PDw sequences provided best contrast to measure the volume of necrosis. Each patient showed a reduction of necrosis after ACD (17.7 % to 90.8 %, mean 43.0, SD 24.2). The granulation zone around the graft could especially be visualised by T2w TIRM and PDw sequences. The arrangement of different layers correlated with histological findings. Conclusion: Structural changes and reduction of necrosis after ACD can be monitored by MRI. ACD does significantly reduce the volume of necrosis in AVN of the hip. The MRE study after oral administration of PEG solution provides an accurate assessment of small-bowel involvement, allowing an evaluation of disease activity in patients with known CD, reducing the radiation exposure in young patients. Metal artefact reduction in hip prosthesis with iterative reconstructions F. Morsbach 1 , S. Bickelhaupt 1 , G. Wanner 1 , A. Krauss 2 ; B. Schmidt 2 , H. Alkadhi 1 , 1 Zurich/CH, 2 Forchheim/DE Purpose: To evaluate the effect of a novel iterative frequency split-normalised (IFS) metal artefact reduction (MAR) on image quality of computed tomography (CT) in hip-prosthesis. In the first study-part, an artificial hip-phantom with steel and titan-based shafts, using three inlays of water, fat and contrast-media placed in the pelvis, was used to test and optimise the IFS algorithm. Image quality and accuracy of CT number measurements of inlays were determined. In the second study-part, 41 consecutive patients with unilateral (n=32) or bilateral (n=9) hipprosthesis were included. Datasets using filtered back projection (FBP), IFS and a previously published MAR algorithm using linear-interpolation were reconstructed. Two readers evaluated axial, coronal and sagittal CT image reformations for overall image quality and evaluated image quality of pelvic organ depiction; CT numbers in the urinary bladder, gluteal muscle and subcutaneous fat were measured. Results: Ex-vivo experiments revealed the best image quality for IFS. Measurements of CT numbers of the inlays were more accurate for IFS. In patients, we found a significant improvement in overall image quality for all reformations (P < 0.001) and a significantly increased image quality of pelvic organs (P < 0.001) for the IFS algorithm. CT numbers of the bladder (P < 0.001) and muscle (P=0.043) were significantly less variable for IFS as compared with images reconstructed with FBP and the linear interpolation MAR algorithm, whereas we found no significant difference for fat (P=0.159). The IFS algorithm significantly reduces metal artefacts from hipprostheses, increases image quality and improves measurement accuracy of CT numbers as compared with FBP and linear interpolation MAR algorithms. Purpose: Computed tomographic (CT) colonography is a technique for detecting bowel cancer or potentially precancerous polyps. Because retained fluid and stool can mimic pathology, CT data are acquired with the patient in both prone and supine positions. Radiologists then match endoluminal locations between the two acquisitions to determine whether pathology is real. This process is hindered by the fact that the colon can undergo large deformations that often occur during repositioning of the patient. Automated registration between datasets could potentially improve efficiency and diagnostic accuracy. We have developed software to establish correspondence between prone and supine endoluminal surfaces. An initialisation step generates image patches at the positions of haustral folds using depth map renderings and is optimised by virtual camera registration. Additional neighbourhood information is then included in a Markov Random Field model to establish landmark-based correspondences. Subsequently, the complexity of the registration task is reduced by mapping both prone and supine surfaces onto a cylindrical domain in which correspondence is established using non-rigid image registration. Monday recurrences in 3 patients (2 hepatic and 1 lung metastases) but missed a 7 mm sessile polyp and 2 flat lesions. CTC quality was inadequate in the 11% of patients. Conclusion: CTC can be effective and represents a valid alternative to colonoscopy for surveillance for colorectal cancer recurrence after surgery. CT colonography: comparative study of experienced vs nonexperienced radiologists using 3D flythrough approach with and without CAD software F. Vecchietti, M. Rengo, D. Caruso, C.N. De Cecco, D. Bellini, A. Laghi; Latina/IT (fabrizio.vecchietti@gmail.com) Purpose: To compare performances of different experienced readers using a primary 3D flythrough approach with and without the use of a CAD analysis. Methods and Materials: Three readers evaluated 50 patients with 100 endoscopically proved polyps (ranging from 3 mm to 40 mm) and different colonic preparations (18 fluid tagging, 32 full cathartic preparation). Dataset analyses were performed on a GE ADW 4.6 workstation equipped with VCAR colon software. Per-polyp sensitivity, inter-reader agreement, mean reporting time and false positive were evaluated for each approach. Results: Less experienced readers increased per-polyp sensitivity, respectively, from 75% and 64% for 3D analysis to 86% and 74% for primary 3D+CAD analysis with a significant difference (p=0.001 and p=0.04) while no significant differences were found for the expert reader (p=0.06). Less experienced readers were faster when assisted by CAD but no significant differences were found on mean reading time for all readers (p= 0.5/0.07/0.1). Mean false-positive findings for CAD standalone analysis were 12 (+-13). All readers decrease false positive when assisted by CAD especially less experienced ones. Inter-reader agreement was higher among all readers when assisted by CAD ( Methods and Materials: Seventy-five consecutive patients were prospectively randomised into two groups. Both groups followed a low residue diet for two days before the examination. Both preparations were based on fluid tagging, using a iodinate contrast medium (gastromiro). Group 1 received 180 ml of fluid tagging agent the day before the study. Group 2 received 60 ml of fluid tagging agent the day of the exam and 500 ml of a laxative agent (Lovol-esse) the day before the study. Patient acceptance was evaluated using a visual assessment scale. Quality of bowel preparation was evaluated using quantitative (tagged fluid density and number of untagged residue per segment) and qualitative (homogeneity per segment on a 4 point scale) scores. Results: Bowel preparation was complete in all patients. No statistical significant differences for tagged fluid density, number of residue and tagging homogeneity between the two groups were founded. A significant higher patient acceptance was founded in group 2 (P=0.02). The preparation based on the combination of a laxative and a fluid tagging agents was better accepted. Adding a laxative agent to a fluid tagging preparation did not improved image quality but was associated with an higher patient acceptance. Moreover, the if a laxative agent is added to a fluid tagging bowel preparation the amount of iodine can be reduced. Considering the latter as a reference method, CTC examinations were retrospectively and blindly initialisation, the method significantly improved the cylindrical registration (p < 0.001), achieving a mean error of 6.0 mm measured at 1743 reference points. The proposed method can successfully establish correspondence between prone-supine locations on the endoluminal surface derived from CT colonography. The ability to rapidly and automatically match polyps between acquisitions will facilitate CT colonography interpretation. (t.n.boellaard@amc.uva.nl) Purpose: To evaluate whether a single intravenous alfentanil bolus has a clinically relevant analgesic effect compared with placebo in patients undergoing elective CT colonography. A prospective multi-centre randomised double-blind placebo-controlled trial was performed in 90 consenting symptomatic or surveillance patients scheduled for elective CT colonography. Patients were randomised to receive either a bolus of 7.5 μg/kg alfentanil (n=45) or placebo (n=45). The primary outcome was the difference in maximum pain during colonic insufflation on an 11-point numeric rating scale (one-sided t test). We defined a clinically relevant effect as a maximum pain reduction of at least 1.3 points. Secondary outcomes included total pain and burden of CT colonography (5-point scale), most burdensome aspect, side effects and recovery time measured by the Aldrete score. Results: Maximum pain scores during insufflation were lower with alfentanil as compared with placebo, 5.3 versus 3.0 (p < 0.001). Total CT colonography pain and burden were also significantly lower with alfentanil (2.0 vs. 1.6 and 2.1 vs. 1.7, respectively). With alfentanil fewer patients rated the insufflation as most burdensome aspect (56.1% vs. 18.6%; p=0.001). No clinically relevant desaturations occurred. Episodes with desaturations < 90% SpO2 and dizziness were more common with alfentanil (4.4% vs. 37.8%; p < 0.001 and 8.1% vs. 44.4%; p < 0.001). Aldrete scores in the alfentanil group were significantly lower immediately after the procedure, but similar at 30 and 60 minutes. Purpose: To evaluate the accuracy of contrast material-enhanced computed tomographic colonography (CTC) for follow-up after curative surgery for colorectal cancer without evidence of disease recurrence. Methods and Materials: 86 patients underwent CTC and colonoscopy (within 4 months) after colorectal cancer surgery. Patients with the suspicion of disease recurrence underwent pathologic confirmation. Patients performed bowel cleansing and faecal tagging; bowel distention was achieved using CO2. Both prone and supine scans, one after intravenous contrast material administration during the portal phase, were obtained using a 64-detector CT ("Brilliance" Philips with iDose). Images were reconstructed with a section thickness of 0.75 mm, transferred to a workstation and interpreted by one radiologist with experience reading several hundred CTC cases. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CTC for anastomotic and non-anastomotic colonic lesions (metachronous or flat lesions and polips) were determined and compared to endoscopy. Results: CTC detected all 2 anastomotic recurrences, all 3 metachronous lesions (sensitivity and specificity=100%) and a perianastomotic recurrence. In 13 patients CTC depicted 16/17 polips > 5 mm (sensitivity=94.1%, specificity=100%, VPP=100%, VPN=98.6%, accuracy= 98.8%) and in 1 patient detected 1 of 3 flat lesions (sensitivity=33.3%, specificity=100%). CTC enabled detection of extracolonic prevalence and distribution was related to patient gender (p> 0.05). In sigma, advanced disease (grade 2/3) shows a significant positive correlation with reduced colonic distension (p < 0.05). No correlation was found between severity of sigmoid diverticula and symptoms onset. Conclusion: Prevalence and severity of diverticular disease increased over time in all colonic segments. An elevated number of asymptomatic diverticula is present in the right colon. An high percentage of patients with severe sigmoid diverticular disease remain asymptomatic. Accuracy of water enema-MDCT in colon cancer staging: a prospective study C. Feasibility study of low-dose CT colonography using model-based iterative reconstruction: preliminary findings in 20 patients V. Vardhanabhuti, C. Roobottom; Plymouth/UK (vvar@me.com) To compare image quality on computed tomographic (CT) images acquired at standard dose (SD) and low dose (LD) using adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) techniques. Methods and Materials: 20 patients were prospectively recruited for the study with informed consent. They underwent standard dose (SD) and low-dose (LD) CT colonography. Low-dose parameters were based on our phantom study with using vendor-specific automatic tube current modulation known as noise index. Both sets of scans were reconstructed with ASIR and MBIR. Objective and subjective image qualities were assessed as well as diagnostic accuracies for significant lesions (e.g. polyps, cancer, etc). Effective doses for each scans were recorded. Results: Objective image analysis supports significant noise reduction and superior contrast-to-noise ratio with low-dose scans using MBIR technique (p < 0.05) despite being acquired at lower doses. Subjective image parameters were equivalent for LD MBIR and SD ASIR for both colonic and extra-colonic findings. Diagnostic accuracies for polyp detection and other significant lesions were comparable. Dose recorded were substantially lower for MBIR (range 45-75% reduction compared with ASIR) with mean average being 4.2 mSv in our population group. Conclusion: MBIR shows superior reduction in noise whilst maintaining image quality and most importantly substantial dose reduction can be achieved. More patients are being recruited to substantiate diagnostic accuracies data with full results to be presented at the ECR 2013. reviewed by two readers separately respectively having a degree of initial and advanced experience (for both primary 3D view). Calculated values were sensitivity, specificity, NVP, PVP for patient-to-segment and both without and with the use of the CAD system (im3D-Turin) as the second reader. ]of sensitivity, specificity, NVP, PVP reported by the novice radiologist were respectively: 55%, 76%, 55% and 80%, while the values obtained by the radiologist with advanced experience were equal to 67%, 89%, 75%, 91%. With the use of CAD as a second reader the novice player has achieved an improvement of the sensitivity to 62%, while the skilled reader did not obtain a significant increase of' diagnostic accuracy. The sensitivity and NPV of CTC for flat lesions depend on the experience of the radiologist reader. CAD seems to be an effective aid for the novice radiologist only. (thomas.knogler@meduniwien.ac.at) Purpose: To predict early treatment response with three-dimensional texture features (TF) in patients with Hodgkin lymphoma (HL) after radio-chemotherapy extracted from contrast-enhanced CT. Methods and Materials: 21 patients with histologically proven HL were included in this study. Contrast-enhanced (18)F-FDG PET/CT was obtained on a dedicated PET/CT scanner. Volumes-of-interest and long-and short-axis diameter were manually defined on 48 HL manifestations prior and post-radio-chemotherapy on the CT image stack. Three-dimensional texture features derived from the grey-level histogram, co-occurrence matrix, run-length matrix and absolute gradient were calculated for the VOIs. A stepwise logistic regression with forward selection was performed to find classic radiologic features (i.e. lesion diameter, lesion volume) and TF, which correctly classify treatment response (i.e. full response and partial response). Classification in PET/CT was used as reference. Results: Difference in short axis diameter best fit as classic feature with a sensitivity of 100%, a specificity of 54.5% and an accuracy of 89.6%. Combination of "S_0_0_1_Entrp" and difference of "vertl_fraction" best fit as TF with a sensitivity of 97.3%, a specificity of 72.7% and an accuracy of 91.7%. Conclusion: Texture features extracted from contrast-enhanced CT in patients with HL are superior in differentiation between responders and non-responders without the need for PET examinations, compared to classical radiological features. However, PET/CT as state-of-the-art imaging technique has a sensitivity and specificity > 90%, so that further research with larger patient number is needed to investigate this new method. (melvin.danastasi@med.uni-muenchen.de) Purpose: To evaluate the agreement between true tumour volume and tumour volume derived from (i) a new formula based on longest lesion (RECIST) diameter, (ii) a new formula based on longest diameter and longest orthogonal (WHO) diameter. Methods and Materials: 89 baseline and follow-up CTs were available in 20 patients with metastastic colorectal cancer from the randomised phase II multicenter CIOX trial. Target lesions were defined at baseline and followed over time. Lesions were evaluated by (i) semi-automated volumetry using Siemens Syngo.via and (ii) volumetric assement using a newly developed formula based on manual measurement of the longest diameter and the longest orthogonal diameter. True, WHO-and RECIST-based volumes were calculated. We compared the agreement of the true volume to the WHO-and RECIST-based volume. We also compared the agreement between 'true' and WHO-based volume relative changes by means of the intraclass correlation. Results: A total of 151 lesions were evaluated. Using a variance components model it was shown that the difference between true and RECIST-based volume is statistically significant (p < 0.001) indicating a substantial constant bias. Purpose: Tumour treatment by retargeted truncated protein derivatives of the human tissue factor (tTF) results in tumour vessel infarction, necrosis and subsequent tumour growth retardation and regression. A novel method of gadofosvesetenhanced MRI, that enables the visualisation of the response to this treatment in real-time, is introduced. Methods and Materials: Dynamic gadofosveset-enhanced MRI (3 T) was performed in eight tumour-bearing (U87) nude mice. In the course of an ultrafast T1-weighted gradient echo sequence, a gadolinium-based blood pool contrast agent (gadofosveset trisodium) was injected intravenously via a tail vein catheter. After the maximum contrast intensity inside the tumour was obtained, 150 µl of tTF-NGR (a retargeted tTF derivative which binds to CD13-overexpressing tumour endothelial cells) were injected intravenously via a second tail vein catheter (n = 4; saline solution as control: n = 4), and the contrast behaviour of the tumour was monitored by region of interest (ROI) analysis. Results: Following the injection of tTF-NGR (approx. 500 sec. after the beginning of the sequence), the contrast intensity inside the tumours of the treated mice decreased more instantly and more strongly than in the tumours of the control mice (AUC 1121.3 ± 0.65 vs. 1164.4 ± 0.52 AU). Conclusion: Gadofosveset-enhanced MRI allows for the visualisation of the therapeutic response of tumours to anti-vascular treatment in real-time. Considering the intended clinical application of tTF-NGR, this method might be a simple and quick surrogate parameter for the monitoring of the therapeutic response to vascular disrupting agents in humans. Purpose: The specific growth pattern of pleural mesothelioma along the pleural surface makes therapy monitoring using common measurement criteria, such as RECIST 1.0, difficult. Therefore, Byrne et al. developed modified RECIST criteria for pleural mesothelioma. In this study we evaluated the accordance between experienced and less experienced readers for RECIST 1.0, RECIST 1.1, mRE-CIST, and WHO. Methods and Materials: A total of 43 baseline and follow-up-CT scans from 15 patients from a clinical multi-centre pleural mesothelioma trial were retrospectively evaluated by different experienced radiologist (about 1 year and more than 10 years), who selected target lesions independently according to mRECIST, RECIST 1.0, RECIST 1.1 and WHO criteria. CT scans were then re-measured after an interval of greater than one month. The inter-and intra-reader variability using the different response criteria was analysed. Results: Both, the intra-reader-and inter-reader variability were best when using mRECIST (95 % limits of agreement of -28.4/ 12.9 and of -32.1/ 20.7) compared 'with RECIST 1.0, RECIST 1.1 and WHO. Further, regarding the objective response (PR = partial response, SD=stable disease and PD = progressive disease), mRE-CIST showed the most reliable intra-observer outcome with only one differently classified examination and the most reliable inter-observer outcome with four differently classified examinations. Conclusion: Our results suggest that mRECIST is most reliable for treatment response evaluation of pleural mesothelioma between experienced and less experienced readers compared with RECIST 1.0, RECIST 1.1 and WHO. To confirm these findings, the inclusion of further readers and more patient data is warranted. Use of multimedia structured reporting for tumour response assessment D. Munich/DE (wieland.sommer@med.uni-muenchen.de) Purpose: The aim of this study was to define the role of MRI in the pretherapeutic prediction of treatment response in patients with liver metastases of neuroendocrine tumours (NET) undergoing radioembolisation. In 45 patients with proven hepatic metastases NET, MRI was performed at baseline (3 T MRI scanner, Gd-EOB-DTPA). Furthermore, PET-CT examinations with somatostatin-specific tracer 68 Ga-DOTATATE were performed at baseline. The following imaging predictors were defined: patient age/gender, proliferation marker Ki-67, tumourload (%), vascularisation of metastases, tumour necrosis and haemorrhage. The status of somatostatin receptor was defined by analysing mean and maximum SUV in PET-CT. As primary end point we defined the progression-free survival (PFS) using RECIST criteria in MRI follow-up examinations (every 3 months). The effects of the predictors on the progression-free survival were analysed using Kaplan-Meier statistics. Results: The mean follow-up time was 445±411 days. The mean PFS was 699 days (95%CI 326-964). Hypovascular metastases showed significant earlier progress (255 vs. 727 days; p < 0.01). A proliferation marker < 2% was significantly associated with a longer PFS than a proliferation marker between 2-20% and > 20% (p < 0.001 Dimensions System 3D (Hologic®). The distribution among the ACR density patters was studied. All women underwent a "combo" study, which consisted of a 2D-DM (2 projections) and 3D-DBT (2 projections). The increase in the detection of additional breast cancers due to the 3D-tomosynthesis studies has been evaluated. Chi-square test with SPSS for windows (15.0 Chicago, IL) has been used to evaluate if there were any statistically significant differences (p < 0.05 was considered statistically significant). The clinical, radiologic and pathologic findings are described. Results: Among all ACR density pattern, 15 breast cancers were diagnosed with the 2D-DM studies (detection rate 0.54%). 7 additional cancers were diagnosed due to the 3D-DBT imaging findings (four in ACR density patter 2, one in ACR density pattern 3 and two in ACR density pattern 4). The global detection rate increased to 0.79%. No statistical differences were found regarding the detection rate among all density patterns. Conclusion: In our group of patients the use of 3D-DBT combined with conventional 2D-DM increased the rate of breast cancer diagnosis from 0.54 to 0.79%. No statistical significant differences were found among all ACR density patterns. 3D-DBT may be useful not only in dense breasts (ACR 3 and 4) but also in medium density breasts (ACR 2). exams. We present a structured reporting system, called ViSion, which captures a radiologist's measurements and key images in an efficient manner to generate disease timelines and automate the calculation of RECIST. We analysed serial radiology reports from ten patients with cancer to determine if radiologists reported tumour measurements, saved measurements in PACS, and whether there was correlation of tumour metrics between exams. In addition, we created a structured reporting solution that uploads screen captures and audio descriptions of image findings to a computer server where each finding is labelled with anatomy and pathology terms, presented in a multimedia structured report, and can be used to calculate RECIST. Results: The analysis of baseline and subsequent radiology reports revealed that radiologists reported measurements in 90% of cases, saved measurements in 20% of baseline and 50% of follow-up studies, and correlated measurements between exams in only 40%. The application of ViSion enabled a means to record tumour measurements in 100% of cases by providing a visual record of where target lesions were previously measured, facilitating the linking of image findings between examinations and displaying the findings in disease timelines. The ViSion structured reporting system provides a means for more reproducible tumour response assessment. To identify the potential of breast MRI vs. standard prognostic factors to predict tumour recurrence after successful treatment of primary breast cancer. Methods and Materials: Consecutive patients receiving staging MRI and subsequent guideline-approved therapy of primary breast cancer at our academic breast centre were investigated. Standard prognostic factors including TNM staging, tumour typing, tumour grading, progesterone/estrogen receptors, HER2NEU score and associated DCIS component were assessed. Follow-up was performed (endpoint: "tumour-recurrence" after complete remission). For analysis of breast-MRI a dedicated CAD software was used (computer-aided analysis). It enables semi-automatic analysis of enhancement characteristics of the whole tumour (3D analysis of early vs. delayed phase) and the "hot-spot" (i.e. voxel with highest washin/wash-out ratio). Potential of breast MRI characteristics vs. standard prognostic factors to stratify the endpoint separately and in combination was investigated using logistic regression. To identify significant and independent predictors, backward feature selection was applied (p entry /removal: < 0.05 /> 0.01). Results: 223 patients were included (endpoint: n=13/5.8%, loss-to follow-up: n=7/3.1%). If tested separately, logistic regression identified moderate potential for breast MRI (AUCMRI=0.79, p=0.001) and standard prognostic factors (AUC-standard=0.71; p=0.01) to stratify the endpoint. If breast MRI characteristics and standard prognostic factors were combined, predictive performance could be increased considerably (AUCcombined=0.90, p < 0.001, sensitivity=84.6%, specificity=87.3%). Feature selection identified one standard prognostic factor (M-Stage) and four breast MRI characteristics (hot-spot: Wash-in, washout-ratio; 3D-analysis: tumour voxels showing wash-out plus weak wash-in, tumour voxels showing plateau and weak wash-in) as the most significant and independent predictors of tumour recurrence. Purpose: To estimate the influence of breast density on diagnostic performance of DBT added to DM (DM+DBT), focusing on recall rate reduction. Methods and Materials: Seventy-five women were recalled for 77 findings on DM screening examination and further investigated according to usual protocols (additional DM views, ultrasonography, and/or core needle biopsy). The final conventional assessment was: 7 cancers (4 invasive ductal carcinoma, 2 invasive lobular carcinomas) and 68 negative/benign cases. Before this conventional work-up, 1-or 2-view DBT was obtained (Giotto, IMS, Italy) for an off-line further evaluation. Two independent readers, blinded to final conventional assessment, retrospectively assigned a BI-RADS score to each lesion on both DM only and DM+DBT. Breast density was scored according to ACR categories from 1 to 4. χ 2 test was used. Results: None of the 7 cancers was missed on DM+DBT by each of the two readers; of 14 readings, 7 (50%) had an increased BI-RADS score. Of 136 readings of 68 benign/negative cases, density was ACR1 in 24 (18%), ACR2 in 60 (44%), ACR3 in 42 (31%) and ACR-4 in 10 (7%); the BI-RADS score was increased in 3 (2%), unchanged in 61 (45%) and decreased in 72 (53%). BI-RADS was decreased for 11/24 (46%) ACR1, 34/60 (53%) ACR2, 25/42 (59%) and 4/10 (40%) ACR4 (p= 0.595). Conclusion: Breast density does not influence the capability of DBT, as added to DM, to decrease the BI-RADS score of negative/benign cases recalled for further assessment at screening DM. Recall rate reduction by adding double reading digital breast tomosynthesis (DBT) to digital mammography (DM) L.A. Carbonaro 1 , R.M. Trimboli 1 , N. Verardi 1 , K. Khouri Chalouhi 2 , G. Di Leo 1 , F. Sardanelli 1 ; 1 San Donato Milanese/IT, 2 Milan/ IT (luca.carbonaro@gmail.com) Purpose: To estimate the reduction in recall rate induced by adding double reading DBT to DM. Methods and Materials: During 21 weeks of screening-activity, women with at least one mammographic suspicious finding were further investigated according to usual protocols (additional views, ultrasonography, and core needle biopsy). Before this standard exams, 1-or 2-view DBT was acquired (Giotto, IMS, Italy). Of a total of 1,286 DM screening-exams, 74 were initially recalled (recall rate of 5.8%) for 77 suspicious findings. Two independent readers (who did not perform initial standard reading and blinded to final diagnosis) retrospectively evaluated DM and DBT. Each lesion was scored according to BI-RADS classification, considering 3, 4a-b-c, and 5 as recalls. Results: Two DBTs (two findings) were excluded for technical problems. At combined DM+DBT evaluation each of the two readers recalled 37/72 (51%) women; considering each case judged as BI-RADS 3-5 by at least one of the two readers as recalled (double reading), a total of 49 cases were recalled with a reduction in recall rate of 23/72 (32%). Of 14 readings of 7 cancers (5 IDCs, 2 ILCs), we had BI-RADS upgrade for 7 (50%), confirmation for 6 (43%), and downgrade for 1 (7%). Of 136 readings of 68 negative cases, we had a BI-RADS upgrade in 3 (2%), confirmation in 61 (45%), and downgrade in 72 (53%). No cancers were missed. The use of double reading DBT as an adjunct to DM could allow for a reduction of recall rate by 32%, from 5.8% to 3.9%. Detection rate for suspicious lesions of digital breast tomosynthesis in combination with digital mammography or 2D central projection imaging C. Zuiani 1 , P. Clauser 1 , V. Londero 1 , C. Molinari 1 , R. Girometti 1 , A. Taibi 2 , S. Vecchio 3 , M. Bazzocchi 1 ; 1 Udine/IT, 2 Ferrara/IT, 3 Bologna/IT (clauser.p@hotmail.it) Purpose: Based on a novel approach, Digital Breast Tomosynthesis (DBT) may simultaneously acquire 2D and 3D images of the breast. Variable dose geometry is used to give a sufficient dose in the central projection (2D-CP) for that image to be a 2D mammogram. We aimed to assess the detection rate for suspicious lesions (ACR-BIRADS 3-5) of DBT associated with Digital Mammography (DM) or 2D-CP. Methods and Materials: 45 asymptomatic women who performed DM and DBT with 2D-CP as screening examinations were included. Two experienced radiologists, blinded to final diagnosis, evaluated images in separate sessions according to two different strategies of reading: DM+DBT (set-A) and 2D-CP+DBT (set-B). They assessed breast lesions as benign or suspicious in case of ACR-BI-RADS scoring of 1-2 and 3-5, respectively. Discordant cases were reviewed in consensus. Purpose: The aim of this study was to demonstrate the diagnostic significance of digital mammography with tomosynthesis (3D) versus digital mammography (2D) in the group of histologically proven multicentric breast cancer. In the group of 110 patients examined in this study, 2-D mammography showed suspicious breast lesions. All patients were sent to the Oncology Institute of Vojvodina for further examination and biopsy. At our institution after initially clinical breast exam, 2D and 3D mammography were performed in the same act. All imaging procedures were performed on Hologic Selenia Dimensions equipment. Two radiologists independently read mammograms and core needle biopsy were performed in all BIRADS 4 and 5 groups. All patients had fibroglandular or heterogeneously dense breasts (ACR2 and ACR3). Results: In the group of 110 patients, pathologic findings revealed 80 unifocal and 30 multicentric cancers for a total of 152 malignant foci. All unifocal cancers were detected by both methods. With 2D mammography, additionally 15 suspicious lesions were found and using 3D mammography 31 suspicious mass were found. Both 2D and 3D mammography showed the same 15 lesions but 3D mammography showed 16 "new" lesions which were obscured on 2D mammography. Overall sensitivity was 82% (125/152) for 2D mammography and 94% (141/152) for 3D mammography (p < 0.05). Results showed that in 10% of multicentric foci were in situ carcinomas (DCIS). Conclusion: 3D mammography was more sensitive than 2D mammography for the detection of multicentric foci in fibroglandular or heterogeneously dense breasts. The role of tomosynthesis after normal mammography according to ACR density patterns J. Etxano, P. Slon, I. After a standardised preparation with 1L of oral water over 60 min, the patient is asked to empty the bladder. Initially the patient receives intravenously (iv) 20 mg of furosemide. Contrast administration consists of a fixed iv volume of 110-120 ml Iobitridol 300 mgI/ml followed by 20 ml saline solution injected at a rate of 2-3 ml/s. After 10 min and subsequently every 2 min first low-radiation scouts are acquired Breast tomosynthesis versus digital mammography: evaluation of diagnostic potential in women with abnormal screening mammograms M. A. Shaaban; Cairo/EG (marwaadelmm@hotmail.com) Purpose: To compare the diagnostic potential of digital mammography with tomosynthesis. Methods and Materials: 100 women with abnormal screening mammograms,187 findings, and definite imaging or histopathological diagnosis were included. The screening mammography interpretation consisted of direct comparison of the tomosynthesis (DBT) examination with full field digital mammography (FFDM) images. The study radiologists subjectively rated the equivalence of the image quality of both the DBT and the FFDM examinations with no use of additional mammography, magnification views or comparison mammography. The next step was categorising the findings in both FFDM and DBT separately according to BIRADS classification and the statistical analysis evaluated the p values of DBT and FFDM as well as their sensitivities. Results: All findings categorised as BIRADS 3 according to mammography showed reduction in number,particularly for masses, when examined with tomosynthesis. The image quality of tomosynthesis was subjectively rated as equivalent (53.5%) or superior (43.3%) to digital mammography in 96.8% of the total of findings; the test was highly significant (p < 0.001). For masses, tomosynthesis image quality was rated as equivalent in 40.5% or superior in 58.1% of findings. Masses were 53% of findings in which tomosynthesis had superior image quality. The FFDM Sensitivity was of 91.9 % compared with 95.2% for DBT. The diagnostic potential of digital breast tomosynthesis is superior to that of full-field digital mammography by evaluating their image quality and their sensitivity. Based on a subjective analysis, DBT showed a significantly higher image quality compared with digital mammography in all finding types, especially in the characterisation of masses. Purpose: To compare discordant screen-detected cancers in FFDM ("2D-mode") versus 2D plus tomosynthesis (2D+3D or "combo-mode") in a population-based screening program. Methods and Materials: Oslo Tomosynthesis Screening Trial (OTST), a large prospective study comparing FFDM with 2D plus tomosynthesis in breast cancer screening, is part of the Norwegian Screening Program. Women 50-69 are invited biannually to mammography using independent double reading. The two main arms of OTST have independent double reading. One 2D arm is modified with CAD and one combo-arm with synthetic 2D. The four arms are read by independent radiologists. From 22.11.2010 to 31.12.2011, 121 screen-detected cancers were found. Results: Cancers detected: Arm A (conventional FFDM) 77, arm B (2D+CAD) 77, arm C (2D+tomo) 101, and arm D (synthetic 2D+tomo) 94. Merging arm A and B ("2D-mode") and C+D ("combo-mode"), 90 cancers were detected by "2D-mode" and 119 by "combo-mode" (32.2% relative increase). Discordant rate (screendetected cancer with TP score by only one reader) was 28.9% (26/90) for "2D-mode" and 36.1% (43/119) for "combo-mode". For cancers manifesting as spiculated mass or distortion (n=63) the discordant rate was 31.0% (13/42) for "2D-mode" and 30.6% (19/62) for "combo-mode". For cancers with microcalcifications the values were 25.7% (9/35) and 39.5% (17/43), respectively. Conclusion: Combined FFDM and tomosynthesis showed a 32% relative increase in cancer detection as compared with FFDM. Discordant cancer rate was approximately the same or higher for "combo-mode" as compared with "2D-mode". Independent double reading should be the standard of care when tomosynthesis is implemented into mammography screening. Purpose: Within narrow limits, the CT estimated size influences the prognosis for spontaneous passage of a ureteral calculus. In the present experiment, we tried to reduce the inter-reader variability in urinary calculus size estimation by measuring the variability before, immediately after and late after a training session. A retrospectively generated anonymous urinary calculi CT image data bank consisting of 50 unenhanced CT-stacks demonstrating ureteral or kidney calculi was used. Eleven readers, radiologists and residents (mean experience 13 years) independently estimated the largest axial diameter of the calculi in three sessions: baseline, post-training and follow-up. Immediately before the post-training session each reader received training on eight calculi aimed at reducing inter-reader variability without affecting the mean reader size estimate. Follow-up session was performed four to eight weeks later without further training. Results: Per-calculus standard deviation between readers was 0.44, 0.42 and 0.51 mm and inter-reader limits of agreement were ±1.3, ±1.2 and ±1.5 mm for baseline, post-training and follow-up session, respectively. Friedman test showed significant difference for per-calculus standard deviation (p < 0.001). Pairwise Wilcoxon signedranks test showed increased variability in follow-up session compared to baseline (p < 0.001) and post-training session (p < 0.001). The small reduction in variability in post-training session compared to baseline was not statistically significant. The small statistically non-significant reduction of inter-reader variability from the tested training protocol had no long-term effect, where an increase in variability was seen. Other approaches such as reader-independent urinary calculus size estimation seem more promising for reduction of inter-reader variability. Purpose: To assess the added value of functional sequences, using diffusionweighted imaging and apparent diffusion coefficient value, to conventional MRI imaging examination in the differential diagnosis from benign and malignant focal liver lesions. Methods and Materials: A total of 53 patients with known focal liver lesions including 36 benign (25 angiomas, 8 FNH, 2 abscesses) and 18 malignant (9 metastases, 7 HCCs, 2 cholangiocarcinomas) underwent 1.5-T MRI examination (Achieva, Philips). The study was performed with a phased array multi-coil using a conventional protocol that included also diffusion-weighted imaging (DWI) with different b-values. The ROIs were manually drawn on focal liver lesions and on surrounding normal hepatic parenchyma in ADC maps, and statistical analysis of ADC mean values was performed. Results: Lesions were proved either by follow-up (benign lesions) or biopsy (malignant lesions).Following mean ADC values were obtained for different types of benign lesions: angiomas (1794.27±125, 2x10-3 mm2/sec), FNH (1486.74±156, 8x10-3 mm2/sec), abscesses (1133±145, 5x10-3 mm2/sec) while in the neoplastic lesions were: metastases (1025, 6±93x10-3 mm2/sec), HCCs (887, 6±71, 10x10-3 mm2/sec) and cholangiocarcinomas (1285±25x10-3 mm2/sec). In normal hepatic parenchyma, mean perfusion values were (1158, 4±158, 7x10-3 mm2/sec). A statistical higher values (p < 0.001) were obtained in diffusion parameters among benign than those of malignant lesions (1563±142, 4 vs 1066±138, 3x10-3 mm2/sec). Conclusion: Diffusion-weighted images offer useful quantitative information (by evaluation of ADC maps) that differs significantly in solid and malignant liver lesions, due to tumour different vascularity and cellularity. Purpose: To identify the best MR sequences for pancreatic adenocarcinoma conspicuity and determine whether MR signal and apparent diffusion coefficient (ADC) values correlate with pathological findings. Methods and Materials: 25 consecutive patients with pathologically proven pancreatic adenocarcinoma who underwent MRI (1.5 or 3 T) before surgical resection were included. Fat-suppressed (FS) T1-weighted gradient-echo (GRE), FS T2-weighted fast-recovery fast spin echo, 3D FS dynamic T1-weighted gadolinium-enhanced GRE during arterial, portal and delayed phases and diffusion-weighted imaging (DWI) with b values of 0 and 600 or 800 sec/mm2 were obtained. Two observers reviewed MR sequences for size, signal characteristics and lesion conspicuity using a four-point rating scale. ADC of tumours were calculated. Histological characteristics (differentiation, fibrosis, necrosis) were correlated with MRI features. Results: 95% of pancreatic adenocarcinomas were hypointense on 3D FS T1 GRE arterial phase, which was the best sequence for tumour conspicuity, followed by portal phase. DWI was not useful for delineating 26% of tumours. Maximum diameter at pathological examination ranged from 18 to 60 mm (mean 33 mm). It was best correlated with MR tumour size on DWI. No correlation was found between ADC (mean value : 1.76x10-3 mm2/sec) and differentiation, fibrosis or necrosis. All homogeneous hyperintense lesions on delayed phase (23% of tumours) were predominantly fibrous tumours. Conclusion: 3D FS T1 GRE arterial phase sequence is superior to DWI for pancreatic adenocarcinoma conspicuity but it underestimates the size of the tumour. DWI is the best sequence for size evaluation when the tumour is correctly delineated. Quantitative data analysis of the diffusion-weighted MR-images in the differential diagnosis of metastatic liver disease of colorectal and pancreatic aetiology Y. Savchenkov, S. Bagnenko, G. Trufanov, V. Fokin; St. Petersburg/RU (yura_savchenkov@mail.ru) Purpose: To develop differential diagnosis metastatic liver disease on the basis of quantitative data analysis of DWI. Methods and Materials: 57 metastatic liver lesions colorectal (37 lesions) and pancreatic (20 lesions) aetiology were analysed in 20 patients. We used DWI with the factors b-50,300,800,1200,1500s/mm2. All measurements were carried out within a single axial slice (for each pulse sequence separately). We used the coefficients, calculated on the basis of the ratio measured values in several organs, in different parts of the liver or in one and the same region of the liver. The most informative in the native study is the ratio of SI lesionb300 /SI aorta b300 , SI lesionb50 /SI aortab50 и SI lesionb50 /SI liverb50 (р<0.001). Somewhat less informative demonstrated is the ratio of SI lesionb300 /SI liverb300 и ADC lesion50-300-800 (р<0.001 and р=0.003 Purpose: In clinical practice, the Apparent Diffusion Coefficient (ADC)-map is supposed to eradicate the T2-shine-through effect (T2-STE) potentially affecting the Diffusion-weighted (DW) signal of focal liver lesions (FLLs) at higher b-value. We investigated whether this assumption is valid. Methods and Materials: Included were forty-five patients with 73 focal liver lesions (54 malignant and 19 benign) detected on a 1.5 T system (cysts and haemangiomas were excluded from analysis). DW examination was performed using a single-shot Echoplanar sequence with b values of 50, 500 and 800 sec/mm 2 , leading to the generation of (a) the ADC-map, using a 3-point regression analysis and (b) the exponential ADC-map (E-ADC-map), using the b800/b50 images ratio, which provides a diffusion-weighted image with complete eradication of T2-relaxation time effects. By performing an analysis of differential signal patterns, two experienced radiologists in consensus estimated the prevalence of the T2-STE when combining DW images with the ADC-map or E-ADC-map. Purpose: To develop a novel spectral reconstruction algorithm for digital breast tomosynthesis (DBT) that results in reduced artifacts and improved image quality. Methods and Materials: Current reconstruction algorithms assume that the xray source emits a mono-energetic x-ray beam, resulting in artifacts and possibly sub-optimal image quality. To avoid this, a mathematical model of DBT acquisition that includes the spectral nature of the x-ray source was developed, resulting in a large scale non-linear inversion problem which we solve using an iterative, gradient descent method. The resulting algorithm was tested using breast phantoms with lesions resembling masses and calcifications. The breast phantoms were imaged with a clinical DBT system using the automatic exposure control system. The resulting spectral reconstructions were compared to the system's filtered backprojection (FBP) reconstruction, which assumes a mono-energetic x-ray source. The signal difference-to-noise ratios of the masses in the spectral reconstruction were all superior to those of FBP by a mean factor of 2.6. In addition, the masses exhibited better homogeneity and no artifacts in the direction of x-ray tube travel, typically seen in DBT images. The microcalcifications also resulted in improved signal difference and without artifacts seen in the FBP reconstructions. Subjective comparison of images of heterogeneous breast phantoms showed an overall improvement in image quality, substantial reduction of artifacts, and lower noise. Conclusion: Spectral reconstruction can improve image quality and reduce artifacts in DBT images. This new algorithm also allows for investigation of novel acquisition techniques that could result in further improvements in DBT imaging. Purpose: Phase-contrast radiography is an emerging technique for producing medical imaging with more soft tissue contrast than traditional absorption radiography. The goal of this study is to evaluate the feasibility of phase contrast imaging using grating interferometer for clinical use. We developed a prototype of phase contrast x-ray imaging system using micro-focus x-ray source, grating interferometer and CMOS detector. The source contains a tungsten anode x-ray tube that can operate from 38 kV at 0.35 mA and focal spot size of 0.3 mm. A specification of phase grating was 4.714um period, Ni 6.08um height and 30x70 mm 2 area; and analyser grating was 2.4um period, Au 20.3um height and 20x60 mm 2 area. With application of phase retrieval algorithm, phantoms such as acryl ball, honey bee and goldfish images were obtained. We compared with images of conventional absorption radiography and evaluated the phase intensity by phase stepping method. Results: Phase contrast image shows a detailed view of the edge of the acryl ball. On the phase contrast image there are dark and light lines running along the hole. These lines represent the phase-contrast edge enhancement effect. A similar effect is evident at the honeybee and goldfish images. The phase contrast edge enhancement effect is visible in the phase contrast radiography, but not in either of the absorption contrast image. The phase contrast imaging using grating interferometer will ultimately provide a novel x-ray imaging system that enables with high contrast, which can be valuable in medical imaging such as breast, cartilage and vessels. First in-vitro results of microbubbles as a scattering contrast agent for x-ray dark-field imaging measured at a first pre-clinical x-ray phase-contrast and dark-field CT scanner Purpose: Dark-field and phase-contrast imaging, which generate contrast from ultra-small angle scattering and refraction of x-rays in matter, have been shown to increase soft-tissue contrast and provide complementary information to conventional absorption-based imaging. To further improve image quality and explore possible alternatives to commonly applied iodine-based contrast agents, the use of microbubble-based ultrasound contrast agents as an x-ray scattering dark-field contrast medium was investigated. Methods and Materials: Using the first pre-clinical phase-contrast and dark-field CT scanner with polychromatic x-ray source and grating interferometer installed on a rotating gantry, absorption, phase-contrast and dark-field images of microbubblebased contrast-agent samples were acquired in-vitro. For quantitative comparison, the contrast-to-noise ratio relative to a reference was calculated for varying detector resolutions (29-928 micrometer) in absorption and dark-field images. Results: It was possible to generate an improved contrast-to-noise ratio in the darkfield image compared to the absorption-based image (6.88 versus 1.41, pixel size 29 micrometer) by exploiting the x-ray scattering through microbubbles. With larger pixel sizes (928 micrometer), the relative contrast gain increased to 78.82 for dark field, whereas, with 1.06, it remained in the same order of magnitude for absorption. The proved feasibility of microbubble-based dark-field contrastenhancement with clinically compatible pixel sizes, together with the large potential of the introduction of grating interferometry into a clinical environment as shown by the successful implementation of the technology into a rotating gantry, strongly promote the use of microbubbles as a dedicated dark-field x-ray contrast agent and warrant further investigation in an experimental in-vivo setting. images. Four thicknesses of the combined phantoms were imaged with a digital mammography unit. Of each thickness, four images were acquired under automatic exposure control. Images were displayed under standard clinical conditions: first on two 5 megapixel medical grade monitors calibrated to the DICOM GSDF standard, then on a 6 megapixel colour monitor, displaying the images in green-scale. Greenscale was chosen as this wavelength matches a peak in human visual response. Reading was performed with the Sara 2 software which displays each CDMAM cell under random rotation, reducing reader memorization. Readers performed a 4-alternative forced choice task; five readers scored all images. Results: Threshold gold thickness (TGT) increased as beam quality and thickness increased, indicating a reduction in object detectability with increasing object thickness. Results obtained for the grey-scale display had a higher TGT compared to green-scale results; TGT values obtained with green-scale display were between 7% and 31% lower than grey-scale display TGT. P values for the different diameters obtained from Wilcoxon matched pairs tests ranged from < 0.01 to 0.68 for 2 cm and < 0.01 to 0.44 for 7 cm. Conclusion: Observer performance measured by c-d curves was equal or better for images displayed in green-scale rather than grey-scale, indicating potential benefit for using green-scale displays in medical applications. Volumetric breast-density measurement using spectral mammography Purpose: Volumetric breast density (VBD) quantification is useful for assessing diagnostic accuracy and the risk of developing breast cancer. The purpose of this study is to evaluate spectral imaging as a method to improve the accuracy of VBD measurements compared to conventional non-spectral methods. The VBD is the volumetric fraction of fibro-glandular tissue in the breast. To measure VBD in a conventional non-energy resolved mammogram, assumptions have to be made on the breast thickness. Spectral imaging, on the other hand, enables simultaneous measurement of breast thickness and glandularity by employing the spectral difference in x-ray attenuation between adipose and fibro-glandular tissue. Spectral mammograms were acquired in a single exposure using a photon-counting mammography system. The VBD was measured by material decomposition based on calibration to tissue-equivalent material. For reference, VBD was measured with a conventional non-spectral method in a similar group of patients. Results: Spectral mammograms of 75 patients, aged 50-69 years, were examined. The correlation in VBD between contralateral breasts was r=0.97. 246 patients were examined with conventional methods, which returned a correlation between contralateral breasts of r=0.92. The VBD distribution was similar in the two groups as measured with the two different methods. Conclusion: Spectral imaging provides an efficient measure of VBD. The VBD distributions over the group of patients were comparable in the spectral and nonspectral measurements, but the correlation between contralateral breasts was tighter using spectral imaging, which indicates higher consistency. Purpose: The feasibility of monochromatic dual-energy x-ray absorptiometry (DEXA) using multilayer reflector for precise measurement of bone mineral density (BMD) was examined. Methods and Materials: A multilayer mirror was fabricated to select an x-ray peak with an energy of 40 keV and 59.3 keV generated from an x-ray tube with a tungsten target. Experimental set-up of monochromatic DEXA was installed by dual-energy of monochromatic x-rays source and CZT detector. The performance of the system was evaluated using a DEXA phantom, spectrometer and radiation dosimeter. We compared the image quality and the attenuation reduction characteristics of the phantom to determine precision of BMD on conventional polychromatic and monochromatic DEXA. Purpose: High vessel attenuation and a high contrast-to-noise (CNR) ratio are prerequisites for highly diagnostic abdominal CT angiography (CTA) examinations. We compared image-quality of standard 120 keV polyenergetic images (PEIs) with calculated low-keV monoenergetic images (MEIs) in dual-energy CTA studies of the abdomen. Methods and Materials: Datasets of fifty patients (42 men, 71 ± 10 years) who underwent abdominal dual-energy CTA were retrospectively evaluated. The 80-and 140-keV dual-energy image data was used to calculate MEIs in 10-keV intervals from 120 keV to 40 keV. Vessel attenuation and image noise were measured in three regions-of-interest (infrarenal aorta, external iliac artery and superior mesenteric artery) and the signal-to-noise ratio (SNR) and CNR were subsequently calculated. Differences between measurements in MEIs and PEIs were evaluated using the Student's t-test. Results: SNR and CNR of 70-keV MEIs were highest compared to MEIs at other low-keV levels. When comparing MEIs at 70 keV to PEIs, vessel attenuation and image noise were significantly higher in MEIs in all three regions-of-interest (+14%, +13%, +14%; p < 0.05 and +12%, +6%, +9%; all p < 0.05). SNR was slightly increased in 70-keV MEIs (+4%, +7%, +6%; p < 0.05). CNR was also significantly higher in MEIs when compared to PEIs (+18%, +16% and +18%; p < 0.05). Purpose: It was shown in mice the exposure to a high fat (HF) diet during early development increased the susceptibility to high-fat diet-induced hepatic steatosis and decreased markers of hepatic mitochondrial function. We aim to investigate whether early exposure to a HF diet also increases the susceptibility to cardiac fat storage and diminishes cardiac mitochondrial function and ejection fraction. Methods and Materials: Male and female C57BL6 mice were fed a HF diet (45% kcal fat) or standard chow diet (9% kcal fat (LF)), starting at least 6 weeks before conception and continuing during gestation and lactation. From weaning onwards, all offspring were fed the HF diet, generating two groups: HF/HF and LF/ HF. Cardiac function and myocardial fat content were measured in male offspring at 15 weeks of age (n=26) using magnetic resonance imaging and spectroscopy on a 7T MR System (Bruker Biospin GmbH). Cardiac mitochondrial respiration was determined in parallel groups (n=11), using high resolution respirometry (OROBOROS Instruments). Results: At 15 weeks of age, the HF/HF group showed significantly higher cardiac lipid content (p=0.02) compared to the LF/HF group. No significant differences in cardiac mitochondrial function and ejection fraction were detected. Conclusion: Mice exposed to HF feeding during early development were more susceptible for high-fat diet-induced cardiac lipid accumulation. This was not (yet) accompanied by decreased mitochondrial function and/or decreased ejection fraction. Cardiac and hepatic iron and heart function by MR in thalassaemia major patients treated with combined deferiprone and desferrioxamine regimen versus monotherapies: a multi-centre, observational and prospective study C. LGE was significantly smaller in follow-up compared to the first examination (p=0.023). In multivariate regression analysis, RV oedema was the only parameter that was associated with a significant improvement of RV-EF. Conclusion: The significant decrease of LGE in the follow-up examination implies that the area of hyperenhancement might represent necrosis. We furthermore conclude that the extend of RV scar is too small to permanently impair RV-EF function in the majority of patients in follow-up. Purpose: The factors governing periprocedural myocardial injury (PMI) and its influence on the prognosis at follow-up are not completely clear. We used delayed enhancement magnetic resonance imaging (LGE MRI) to assess myonecrosis after PCI. Methods and Materials: Forty-three patients with stable coronary artery disease were studied with 1.5 T MRI before and after (within 72h) stenting of bifurcation lesions. The left ventricular function and LGE were assessed. We performed angiographic measurements of the vessel diameters, and bifurcation angles pre-and post-intervention. Systolic-to-diastolic increase of T1 was above average in lateral (p < 0.0001) and apical (p < 0.0001) segments. Conclusion: T1 relaxation times of normal myocardium differ significantly between diastole and systole at 1.5 T. Their strong correlation facilitates translation of diastolic and systolic T1 normal values. Regional deviations from the mean systolic-to-diastolic increase of T1 might be associated with regional differences in myocardial perfusion. Author Disclosures: G. Reiter: Employee; Siemens. A. Greiser: Employee; Siemens. Are the preferential patterns of myocardial iron overload preserved at the CMR follow-up? Results: For each group there was a significant improvement in the global as well as in regional T2* values. For the whole patient population as well as for both groups, at basal the mean T2* value over the anterior region was significantly lower than the mean T2* values over the other regions, and the mean T2* over the inferior region was significantly lower than the T2* values over septal and lateral regions. The same pattern was present at the FU, with a little difference for patients with mild-moderate MIO. In conclusion, a preferential pattern of iron store in anterior and inferior regions was present at both basal and FU CMRs, with an increment of T2* values at FU due to a basal CMR-guided chelation therapy. The anterior region seems to be the region in which the iron accumulates first and is removed later. The effect of partial volume averaging on peak velocity measurements in phase contrast magnetic resonance angiography (PCMRA) J.C.L. Rodrigues 1 , K. Minhas 1 , G. Pieles 1 , C. Bucciarelli-Ducci 1 , R. Tulloh 1 , N.E. Manghat 1 , C.J. Occleshaw 2 , M.C.K. Hamilton 1 ; 1 Bristol/UK, 2 Auckland/NZ Purpose: ECG-gated PCMRA is an established non-invasive in vivo method to measure blood flow. By default, the Siemens Argus PCMRA flow analysis software calculates a voxel averaged peak velocity. The voxel with the highest velocity in the data set is first determined. This value is then averaged with this the velocities of its neighbouring 4 voxels to generate the voxel averaged peak velocity. This may underestimate peak velocity. The aim of this study was to determine if voxel averaging leads to a lower calculated peak velocity. Methods and Materials: 145 peak velocity measurements in 14 different anatomical locations in 37 subjects (healthy volunteers, congenital and acquired heart disease patients) were analysed by default voxel averaging method and single voxel technique and compared. The effects of flow velocity, scan protocol (breath hold versus free breathing) and scanner type (Siemens Symphony versus Siemens Avanto) were also assessed. Statistical significance was defined as P < 0.05. Results: There was a highly significant mean percentage increase in peak velocity of 7.1% when peak velocity was calculated by single voxel compared with voxel averaging technique (P < 0.0001). Significant increases in peak flow were observed by single voxel compared with voxel averaging regardless of patient type, anatomical location, CMR scanner or scan technique in terms of breathing command (p < 0.05). Disabling the voxel averaging technique had no effect on the volume of flow recorded. The use of voxel averaging produces a consistent underestimation of peak velocity. At peak velocities > 300 m.s -1 , the error may be clinically significant, e.g. misclassifying the severity of aortic stenosis. For this reason, it is recommended that for the assessment of peak velocity by PCMRA voxel averaging should not be used. Purpose: To evaluate foetal brain maturation during twin pregnancies complicated with twin-to-twin transfusion syndrome (TTTS). Methods and Materials: Over a period of 4 years, we retrospectively evaluated 44 MRIs of women with monochorionic twin pregnancies complicated with TTTS. MRI scans were realized at an average of 31 weeks of gestation. All pregnancies complicated with TTTS and successfully treated with fetoscopic laser were included. Eighty-eight foetal brains were analysed and compared with an MRI brain atlas and with the co-twin. Biparietal brain diameter, cerebellar transverse diameter, sulcation, operculation, and myelination were analysed. Results: Among the 88 foetuses, 4 (4.2%) developed severe brain damage (unilateral brain atrophy, clastic lesion of corpus callosum with cyst) and showed unusual delay of brain maturation. In others cases of successfully treated TTTS, we found no difference in brain maturation between twins. Conclusion: Brain maturation during twin pregnancies with treated TTTS is well preserved except in cases with a severe vascular complication. Purpose: Very preterm infants suffer a wide range of neurodevelopmental disabilities. The purpose of the study was to assess the relationship between body growth and white matter (WM) microstructure maturation, in very low-birth weight, extremely preterm infants. Methods and Materials: Twenty-seven extremely premature infants (gestational age: 29.11±1.9 weeks) with normal brain US studies and normal MRI at term equivalent age (41.1±1.03 weeks) were enrolled in the study. Using a diffusion-weighted sequence, fractional anisotropy (FA) was measured bilaterally in 16 fibre tracts with the region-of-interest method. The effect of sex and the relationship between somatometric measurements (birth and body weight, crown to heel length and head circumference) and FA was evaluated using a general linear model. Two-tailed Student's t-test was used to assess differences between small for gestational age (SGA) and appropriate for gestational age (AGA) infants. Results: A positive correlation was found between body weight and FA in the anterior corona radiata, the posterior limb of internal capsule, the external capsule, the inferior fronto-occipital fasciculus, the superior longitudinal fasciculus, the middle cerebellar peduncles and the fornix. Decreased FA was observed in the superior longitudinal fasciculus and the fornix in SGA infants (p < 0.05). Conclusion: In extremely premature infants body growth correlates with changes in WM microstructure. Compromised growth at term equivalent age is associated with microstructural abnormalities in areas related to attention, language, memory and executive functioning. The "tail sign" in the differential diagnosis of vermian pathologies in foetuses under 24 weeks: role of foetal MRI P. Relationship between body growth and regional brain volume changes in extremely premature small for gestational age babies L.C. Tzarouchi, A. Drougia, A. Zikou, A. Charisiadi, P. Kosta, L. Astrakas, S. Andronikou, M.I. Argyropoulou; Ioannina/GR (ltzar@cc.uoi.gr) Purpose: Extremely low birth weight and/or low gestational age has been associated with alterations in brain development. The purpose of the study was to assess whether early body growth catch-up reflects regional brain volume (rBV) changes by evaluating small for gestational age (SGA) extremely premature babies (gestational age< 32weeks) at term equivalent age. Methods and Materials: Twenty-five extremely premature infants (GA: 29.8±2.1 weeks) with normal brain US studies and normal MRI at term equivalent age (41.5+1.6 weeks) were enrolled. Thirteen were appropriate for gestational age at birth and at term (AGA), 5 SGA at birth and AGA at term (SGA+) and 7 SGA at birth and term (SGA-). T1-weighted high-resolution 3D images were segmented using the SPM 5.0 and volumes of 90 individual GM areas were calculated using the IBASPM toolbox. Two-tailed Student's t-test was performed to test for differences in rBV between groups. Results: There was no difference in rBV between AGA and SGA+ (body growth catch-up at term). In SGA-(persistent body growth restriction at term), areas of late maturation (frontal lobes, caudate nucleus) presented lower rGMv. There was no difference in rBV between AGA and SGA-in brain areas of early maturation (occipital cortex, thalami) (p < 0.05). In extremely premature babies, body growth catch-up is associated with rBV catch-up at term equivalent age. RBV changes start from areas with great potential for early maturation. Quality control in digital mammography: radiographers practice at 5 hospitals of Lisbon C. Tomás, C. Gonçalves, C.I.S. Reis; Lisbon/PT (claudiatomas90@gmail.com) Purpose: To investigate quality control/(QC) guidelines in use for digital mammography/(DM) in 5 hospitals, to identify radiographer's practice in QC concerning DM and to identify the causes of exam rejection/repetition. Methods and Materials: Questionnaires were developed and applied to 30 radiographers working in DM (computed-radiography or direct-digital-mammography/ (DDM)) in 5 hospitals to characterise the QC practices (guidelines in use, performed tests, tests frequency). Rejected/repeated analyses was performed in one hospital with DDM equipment using the checklist proposed by the International Atomic Energy Agency/(IAEA). Results: Guidelines for QC are followed by 70% (20) of the radiographers: 55% follow American-guidelines, 20% the Portuguese, 15% the European/EUREF and 10% other guidelines. There is more than one guideline followed by radiographers in three institutions. The QC tests performed by radiographers in the same institution (proposed by IAEA to test image acquisition and display systems) were not the same and in the right frequency. The main causes for mammography image rejection/repetition were improper positioning in 85% of the analysed images due to non-inclusion of pectoral muscle in mediolateral oblique projection and inner and outer quadrants asymmetry for craniocaudal projection. Conclusion: In this group of hospitals with DM, there is no uniformity of QC practices. This can have impacts in mammography costs. This may be justified by the absence of certification programs concerning mammography departments. Continuous education and training programs frequency to work with DM are not mandatory and also QC is not required by law in Portugal. An investigation into the psychological anxiety of Maltese women before and after a mammogram C. Falzon; Sta Lucija/ MT (valeview@maltanet.net) Purpose: To investigate whether there is a difference in anxiety levels between Maltese women with and without a family history of breast cancer, before and after a mammogram. The study involved the participation of 150 Maltese women aged 35 years and over. The women were divided into two groups; group 1 without and group 2 with family history of breast cancer. Anxiety levels pre-and Finally, MRI made correct diagnosis in 4 of 6 foetuses with expansive formations, whereas in one of these cases we suspected a choledochal cyst and it was a gastric duplication and in another patient we diagnosed an ascites and it was an intrabdominal cystic lymphangioma. Conclusion: Our preliminary results suggest that MRI has a supplemental value to sonography in anatomic evaluation and characterisation of GI abnormalities. Ultrafast imaging sequence MRI is helpful to confirm, refine or exclude US diagnosis. It also provides useful informations in prenatal counselling and perinatal management. Purpose: In order to achieve high image quality with breast cancer screening mammography, the European guideline recommends training programs dedicated to radiographers. Those training programs are very helpful for practitioners but back at their workplace it might be difficult for them to apply the achieved knowledge in their daily practice. To support radiographers to transfer good mammography practice in their daily screening activity, an online portfolio is realized by each radiographer during the following 6 months after the training session. Methods and Materials: Every month, the trainee radiographer posts about 4 mammography examinations including the quality self-assessment on a dedicated electronic platform. Experienced radiographers from the screening program of western Switzerland comment the picture quality as well as the accuracy of the self assessment. Tips and tricks, to improve quality, are also given. Results: Actually 26 portfolios have been completed. The majority of the radiographers appreciated the personalized comments given by the experts. They found the tips very helpful and they say the portfolio helped them to continuously improve the quality of the performed mammograms. Nevertheless, some radiographers were upset because of the high time investment necessary to the realization of this kind of portfolio. Conclusion: In western Switzerland, where there are many decentralized breast cancer screening units, the online portfolio is an interesting tool to support radiographers with the development and the transfer of competences in their daily practice. Purpose: This study aimed at measuring patient satisfaction in mammography exams and satisfaction-related factors. Methods and Materials: Research was conducted in several private practice clinics with a total of 183 subjects using the Myasthenia Gravis questionnaire for assessing patient satisfaction concerning four dimensions: structure (physical environment), process (performing the exam), discomfort (physical and psychological) and general satisfaction (present and future). Results: Overall patient satisfaction was high (90%), with technical performance (process) and psychological discomfort having the major influence on patient satisfaction. Exam costs and age had very low, or no impact, on satisfaction. Also, the greater patient's education levels, the greater were their demands for process requirements, unlike patients with lower education levels which presented higher satisfaction levels. The great amount of patients of high age groups and respective pathologies may have influenced results when related to satisfaction and education level. The numbers of mammography exams have increased over the years and therefore it is essential to assess patient satisfaction so that improvements can be made. Impacts of digital mammography in radiographers practice L. Painho, T. . The anode-filter combination always used was W/Rh. Global IQ was P (perfect) for CC, while in MLO the mean was G (Good). The radiographers experience varied between 2 and 28 years. The compression force depends on breast compressed thickness. It can vary between 6 and 10N for breast thickness range of 45 to 76 mm. The technique suffered changes when the analogue was compared with digital technologies: the energy is higher, the intensity is lower and the anode-filter has changed from Mo/Mo to Rh/Rh and W/Rh. Breast symmetry absence on CC projection, inframammary folds absence and skin folds presence were the criteria not achieved more frequently in this study, according to European Guidelines on Quality Criteria for Diagnostic Radiographer Images. IQ of all exams was classified as appropriated (perfect and good (362 out 373)). Nevertheless, it is noticeable that some variation exists concerning the radiographer practice when comparing breasts with the same features. The radiographers experience and training can also affect the results. Imaging ethics B. Hofmann; Oslo/ NO (b.m.hofmann@medisin.uio.no) Purpose: The benefits of modern medical imaging technology are obvious. However, the ethical challenges are less acknowledged. The purpose of the study is to highlight and to address core ethical challenges with modern medical imaging. A review of literature in radiology reveals a series of ethical challenges in modern medical imaging that are analysed with standard methods in modern bioethics. The ethical challenges are divided into four categories, i.e. challenges with 1) existing, and 2) new imaging techniques, 3) altered use of existing imaging techniques, and 4) challenges with basic concepts and end points in diagnostic imaging. A series of ethical challenges are identified within these categories, such as (radiation) safety, rationing, and justice (1), implementation without evidence-based outcome (2), reduced diagnostic accuracy, patient autonomy (3), and challenges with underuse, overuse, and futile imaging (4). Conclusion: Behind great benefits of modern imaging, a series of ethical challenges can be identified. While praising the benefits, the challenges need to be appraised to maintain confidence and trust in the profession, as well as a sound and fruitful development in the field. post-mammogram were measured using the well-established State and Trait Inventory for Adults (STAI) developed by C.D. Spielberger. Results: There was a significant difference (p0.05). A negative correlation was obtained when the mean S-anxiety scores (pre: group1, r=-0.123 and group 2, r=-0.245 and post: group1, r=-0.046 and group 2, r=-0.78) of both groups were compared with age. The factor causing anxiety in women was mainly related to the procedure because their anxiety diminished significantly after the mammogram. The correlation showed that those who scored high pre-mammogram anxiety also scored high post-mammogram anxiety. No significant difference in the anxiety levels between the two groups existed before and after the mammogram. A negative correlation existed between age and S-anxiety of the women, resulting in younger women being more anxious than older women. Ergonomic and environmental assessment in digital mammography room: impact on radiographers' activity S. Costa, E. Oliveira, F. Serranheira, S. Viegas, C.I.S. Reis; Lisbon/PT (stefaniebcosta@gmail.com) Purpose: To investigate ergonomic-characteristics of the equipment, environmental conditions and its impact on radiographers' activity and to identify opportunities to optimise the practice and reduce the probability of WRMSDs occurrence. Radiographer's mammography procedures were observed and organized in tasks time-scale-graphic. Interviews were applied to 7 radiographers working in digital-mammography to characterise the practice (work patterns, mammographic equipment, exam room, environmental conditions) and to identify the presence of WRMSDs symptoms. Postural analyses were evaluated through video and pictures acquired during mammography positioning. Measurements of angles were done with Meazure2.0.158 software and classified according to the European Standard/EN100-4:2005+A1:2008. Results: The task-time scale showed that the average duration of each exam is 5 minutes and also that the task which took more time was the indications given to the patient. 45.5% of the radiographers referred that the most exhaustive procedure is the positioning of MLO-view and short-stature patients (22.7%). In this specific case, the anatomical areas that can suffer more WRMSDs are neck, arms and back presenting an angle of 87.2º, 118.6º and 63.6º, respectively. The visual contact with the patient was compromised only during the right-MLO-view acquisition. Considering the environmental conditions the illuminance values are not in accordance with the guidelines. The ergonomic characteristics of the equipment do not provide comfort to the radiographers. In order to reduce the probability of work-related musculoskeletal disorders in mammography positioning and patient safety, new equipment features should be developed. Environmental conditions are adequate concerning the international references for temperature and humidity but not for illuminance. Accuracy of students, and radiographers, with and without, mammography post-graduation in interpretation of mammography images R.B.J. Cópio 1 , K.B. Azevedo 1 , A.F.C.L. Abrantes 1 , L.P.V. Ribeiro 1 , R.P.P. Almeida 1 , C.A. Silva 2 ; 1 Faro/PT, 2 Evora/PT (rita.copio.rc@gmail.com) Purpose: To evaluate the sensitivity, specificity and diagnostic accuracy of radiographers with and without mammography post-graduation and last year students of the Radiography Course in the interpretation of mammography images. A grid of socio-demographic characteristics and View-DEX software (Viewer for Digital Evaluation of x-ray Images) for the interpretation of mammography images by participants were used. Each of the 16 cases was built with the four basic images. After viewing images, the 22 participants showed their level of confidence about the presence of abnormal radiological findings in relation to the case. The results obtained showed values of sensitivity of 81%, 89% and 80% for the last year students, radiographers without post-graduation and post-graduate radiographers, respectively. For specificity, the values were 63%, 75% and 50% for the same groups, respectively. With regard to diagnostic accuracy, the values obtained were 80% for the group of students in the last year, 88% for the group of radiographers without post-graduation and 78% for post-graduate radiographers. The mean response time was 46.9 seconds to the last year students, 59.8 seconds for radiographers without post-graduation and 64.6 seconds to post-graduate radiographers. The sensitivity, specificity and diagnostic accuracy varies between each group. However, there are not significant differences between them. Also, participants with a higher formation have higher average response time. Purpose: To compare different formats of llama-derived nanobodies as alternatives to monoclonal antibodies for specific in vivo near-infrared fluorescence (NIRF) imaging of lymphomas in a mouse model. We used ecto-enzyme ART2 on lymphoma cells as model target and compared three different formats of ART2-specific nanobodies with a conventional antibody (150kD): a monovalent llama nanobody (15kD), a bivalent diabody (30kD), and a bivalent Fc-fusion protein (80kD). All constructs were labeled with AlexaFluor680 and injected in nude mice, bearing ART2-positive and ART2negative tumors. Circulating and excreted conjugates were monitored in plasma and urine and in vivo NIRF-imaging was performed over 24h. Tumor tissue penetration and target binding were analysed by FACS and fluorescence microscopy. Results: In vivo NIRF-imaging revealed specific labeling of ART2-positive tumors but not of ART2-negative tumors with all AF680-conjugates. The smaller nanobody and diabody revealed rapid renal elimination with highest signal-to-background ratios of ART2-positive tumors. The larger Fc-fusion protein and conventional antibody revealed long circulation times in plasma, resulting in unspecific background signals. FACS and Immunohistochemistry of tumors revealed deeper penetration and more homogenous labeling of tumor tissue with the nanobody and diabody than with the Fc-fusion protein and conventional antibody. Conclusion: Renally excreted small nanobody-formats (< 60kD) can be used for specific in vivo imaging of lymphomas with a significantly higher signal-tobackground ratio than larger antibody-constructs (> 60kD) that are retained in circulation. Therefore, single domain and bivalent nanobodies seem particularly suited for short-term diagnostic imaging, whereas reformatted nanobody-Fc fusion proteins appear suited for long-term applications. The design of a dual-functional imaging contrast agent for targeting to tumour endothelial marker (TEM8) Q. Quan 1 , X. Huang 2 , J. Xie 2 , Y. Yan 3 , H. Gao 2 , G. Zhang 1 , X. In control kit+/+ mice, the FMT signal for Annexin V peaked at 6 hours after myocardial infarction with subsequent decrease at 24 hours and 7 days after onset of ischemic injury. KitW/W-v mice revealed an increased and prolonged in-vivo apoptosis signal, which was associated with progressive decline in heart function. Bone marrow reconstitution was able to reduce cardiomyocyte apoptosis and rescue KitW/W-v mice from progressive heart failure. In-vivo apoptosis signal was verified after killed by apoptosis staining using immunohistochemistry (TUNEL) and flow cytometry (Caspase-3). Hybrid acquisition of x-ray computed tomography allowed exact localisation of the FMT signal to the left-ventricle and facilitated organ segmentation and attenuation correction. flow cytometry and determining the dissociation constant. For detecting apoptosis in vivo, CAL-27 tumour-bearing mice were treated with PDT and injected with the annexin V probe two days and two weeks after therapy. The fluorescence intensity of the tumours was evaluated semiquantitatively over time. The annexin V probe showed nearly the same absorption (715 nm) and emission (750 nm) spectrum like the free dye and possessed a high binding affinity to apoptotic cells (KD-value 20 nM). Therapeutic efficiency of PDT could be detected in vivo in the tumours via apoptotic cells shortly after therapy. Our probe accumulated significantly stronger in treated tumours at two days in contrast to two weeks after therapy. Conclusion: In summary, we could successfully image the therapeutic efficiency of PDT with the new designed fluorescence optical annexin V probe. Apoptotic cells could be detected in the tumour short time periods (2 days) but not longer time (2 weeks) after PDT. Bimodal NIRF nanoparticles as an optical and MRI contrast agent for imaging cells of the mononuclear phagocyte system J. Purpose: Even though approaches for multimodal imaging of targeted structures like in tumours have been suggested, fewer investigations have been made on bimodal optical and MR-imaging of inflammatory diseases via passive targeting of cells of the mononuclear phagocytic system (MPS). However, non-targeted nanoparticles (NP) could represent a simple and effective labelling tool being rapidly phagocytized from the blood stream by mononuclear cells which are then migrating to the site of inflammation. For the production of bimodal NP iron oxide cores were enclosed by a near infrared (NIR)-fluorochrome (IR780) and surrounded by a starchmatrix. The spectroscopic and MR-imaging properties of the bimodal particles were determined in agarose phantoms and in vivo using a near infrared fluorescence (NIRF) small animal imaging system and 1.5 and 3 T-MRI, respectively. In vivo optical and MR-imaging was performed on mice with hind leg oedema. Results: A specific NIRF-(average fluorescence signal 0.004 scaled counts/s for 25 µg/ml NP) and MR-signal (1.5 T: r1=6 mM-1 * sec-1, r2=583 mM-1 * sec-1, r2*=613 mM-1 * sec-1) was detected for the bimodal NP in vitro. In vivo-MR and NIRF-imaging studies confirmed specific signalling of the particles within oedema. Conclusion: Our bimodal non-targeted fluorescent iron oxide NP successfully labelled cells of the MPS in vitro and in vivo without specific target recognition by antibodies. Additionally, the ability of specific NIR-signalling and MR-tracking of mononuclear cells makes them suitable for application as a simple and potent NIRF-optical and MRI contrast agent for visualisation of inflammatory diseases. Purpose: Quantitative T1-weighted perfusion imaging is promising. However, current software solutions are still semi-automatic and results are therefore potentially prone to observer-related bias. Surprisingly, this aspect of DCE-MRI is still poorly investigated. We aimed to systematically address this matter using a dedicated imaging protocol and semi-automatic workflow for quantitative pharmacokinetic analysis. An ultra-fast high-spatial and high-temporal resolution protocol was used for T1-weighted perfusion imaging (Magnetom Aera @1.5 T; dynamic view-sharing 3D gradient-echo-sequence/TWIST: temporal-resolution: 1.81s, in-plane resolution: 1.1 mm 3 , 6 ml Gadovist @2 ml/s, acquisition time: 62s). For the assessment of pharmacokinetic parameters (k trans , two-compartment Tofts-model, fast Arterial-Input-Function) a dedicated semi-automatic software solution was used. Enhancing intracranial tumours were independently evaluated two times by one experienced neuroradiologist (> 4000 MRI, 8-year experience in DCE-MRI). Results of pharmacokinetic parameters for each reading were documented in a database. Variability of k trans measurements was assessed by means of reproducibility (concordance correlation coefficient), precision (Pearson ρ), accuracy (Bias correction factor/Cb), reliability (intraclass correlation coefficient), repeatability (coefficient of repeatability/Cr) and systematic bias (Bland-Altmann plot: regression coefficient/Rc). Methods and Materials: 40 patients (mean age 77 years, range 65-93) gave informed consent for this prospective research ethic committee-approved study and underwent two consecutive brain CT-scans, with normal radiation dose (ND) (CTDIvol 57 mGy, 2.6 mSv) and 30% reduced dose (RD). ND scans were reconstructed using filtered backprojection (FBP), while RD scans were reconstructed using FBP and two iDose levels, ID2 and ID4. Image quality was assessed with grading and ranking by six neuroradiologists. Mean Hounsfield units (HU) and noise were measured. Data were analysed using linear mixed models, and the Tukey method for multiple comparisons. Results: For all reconstructions image quality was graded adequate for clinical use. Image quality was graded good/excellent in 93% of cases for ND, 83% of cases for ID4, 79% for ID2, and 67% for RD. For all quality parameters ID4 and ID2 were graded better than RD (p < 0.0055 and p < 0.035) but worse than ND (p << 0.001). Pooled ranking results were equivalent despite considerable variation in individual assessments. HU were identical between reconstructions. Image noise was similar in ND, ID2 and ID4 but higher in RD. Purpose: To determine whether MRI susceptibility-weighted imaging can assist in discriminating between inflammatory pathologies and high-grade glioma. Methods and Materials: Susceptibility-weighted imaging (SWI) was performed at 3.0 T (Siemens Medical Systems) and images were reviewed retrospectively in 17 patients with cerebral inflammatory pathologies and 25 patients with histologically proven high-grade gliomas. Only gliomas without MR findings of haemorrhage on T1WI were included in the study. The morphological pattern of the susceptibility signal and the anatomic positional relationship between the contrast enhancement areas and susceptibility signals were retrospectively reviewed by consensus of 2 reviewers. The SWI morphological pattern was scored as: patchy, nodular, dot-like or linear and designated as inside or outside the zone of contrast enhancement. Results: In total, 17 clinically proven inflammatory diseases (7 parasitic granulomas, 3 inflammation-demyelinating and 7 neurovasculitis) and 23 lesions were reviewed. Patchy, nodular, dot-like susceptibility were demonstrated in both inflammatory and neoplastic lesions, whereas linear susceptibility signals were only identified in the inflammatory diseases. Nine of 23 (39%) susceptibility signals were situated outside the contrast enhancement areas in inflammatory pathologies with no susceptibility signals found outside the border of the contrast enhancement areas among all the high-grade gliomas. Conclusion: On SWI, linear susceptibility signal and/or susceptibility signal located outside the area of contrast enhancement was more frequently presented in inflammatory processes and not found with the high-grade gliomas. This finding may reflect a different pathophysiologic mechanism and distinction of bleeding/ microbleeding occurrence and presentation in inflammatory pathologies compared to high-grade gliomas. Inter-session reproducibility of cerebral blood flow ( The morphology of S1-2 disc, L5 and S1 body and lumbar spinous processes were evaluated. The positions of aortic bifurcation (AB), right renal artery (RRA), superior mesenteric artery (SMA) and conus medullaris (CM) were described. Comparing with WSL, the diagnostic error in numbering vertebral segments on lumbar MRI was evaluated. In lumbarisation, all patients revealed a well-formed S1-2 disc with squared S1 body. A rhombus-shaped L5 body in sacralisation and a rectangular-shaped S1 body in lumbarisation were found. L3 had the longest spinous process. The most common sites of spinal and paraspinal structures were AB at L4 body (71.1%), RRA at L1 body (53.6%) and L1-2 disc (34.1%), SMA at L1 body (55.1%) and T12-L1 disc (31.6%), and CM at L1 body (44.8%). They were located higher in sacralisation and lower in lumbarisation. On lumbar MRI, the diagnostic error in evaluation of vertebral segmentation was 14.1%. Purpose: The presence of intravertebral gas in the lumbar and thoracic spine, usually secondary to trauma, is a well-recognised radiological phenomenon (Kümmel's Disease). However, intravertebral gas within a cervical vertebral body is a common but unknown process. We present a series of 27 patients with gas in the cervical vertebral bodies, not associated with traumatism. The aim of this study is to describe this radiological finding and its possible aetiology. Methods and Materials: Our study group included 27 patients who underwent a routine neck CT examination for reasons not related with the cervical spine. All the patients presented air within a cervical vertebral body. We analysed several factors such as age, sex, location of the gas, history of radiotherapy, chemotherapy, the presence of degenerative disease, previous infections or corticosteroid therapy. Results: The mean age was 67 years (age range 29-82), 21 men and 6 women. The main affected body was C6 (48%), followed by C5 (33%). Most of the lesions were adjacent to the inferior endplate of the vertebral body. Most subjects showed degenerative changes (96%), although none had gas within intervertebral discs. 34 % of the patients received radiotherapy. None of the patients had a history of trauma, infection or treatment with corticosteroids. The presence of gas within a cervical vertebral body seems to be a common but unknown process. This phenomenon could be related with cervical degenerative disease. Further studies should be conducted to verify this hypothesis and to elucidate the nature of this finding. The study comprised of n=12 intracranial tumours, among these meningeomas (n=2), solitary metastasis (n=3), as well as WHO grade II -IV tumours (n=7). Compared to reference tissue, meningeomas were significantly stiffer. Metastases were either slightly firmer or softer than reference tissue. WHO grade II and III tumours (n=4) were softer than white matter in all cases. The highest loss of tissue stiffness was represented by WHO grade IV tumours. Viscoelasticity parameters were supplemented by a histopathology work-up. In summary, high WHO grade tumours were significantly softer than tumours of lower staging, the range of metastatic viscoelasticity was slightly higher than primary brain tumours. MRE was well tolerated by all patients. Conclusion: MR elastography of cerebral tumours at 3 Tesla reliably quantifies tissue firmness for preoperative planning. According to our histology correlated preliminary results, tumour viscoelasticity may be an additional diagnostic parameter for non-invasive tumour differentiation. Intra-and inter-scanner test-retest reliability of whole-brain arterial spin labeling perfusion MRI B. Wu, X. Wu, X. Lou, M. Ge, L. Ma; Beijing/CN (646173826@qq.com) Purpose: Perfusion MRI can be used to identify and monitor patients with acute ischaemic stroke. The objective of this study was to investigate whether it is possible to pool together whole brain arterial spin labelling (ASL) perfusion imaging data at different times, or from different scanners, located at two different sites. Eight healthy subjects were scanned on two different 3.0 T scanners with 3D pseudo-continuous labelling technique. Scans were repeated intra-session and inter-session after 7-30 days. The ASL data with two postlabelling delay time (PLD) of 1.5 and 2.5 seconds were acquired. High-spatial-resolution whole brain T1-weighted images were also acquired for image registration and normalisation into a standardised space within the SPM8. The cerebral blood flow (CBF) values of grey matter, white matter, frontal lobe, parietal lobe, occipital lobe, temporal lobe, putamen, posterior cingulate, and thalamus were extracted for comparison, using WFU Pickatlas tool. The intra-and inter-scanner reliability was evaluated with the intraclass correlation coefficient (ICC Purpose: To quantify the changes of myocardial transverse relaxation times (ΔT2*) induced by hyperoxic respiratory challenge at different field strengths in an intraindividual comparison of healthy volunteers. Methods and Materials: Blood oxygen level-dependent (BOLD) cardiovascular magnetic resonance (CMR) data were acquired in ten healthy volunteers (5 women; 5 men; median age 29 years, range 22-35 years) at 1.5 T and 3.0 T. Medical air (21% O2), pure oxygen and carbogen (95% O2, 5%CO2) were alternatively administered in a block-design temporal pattern to induce normoxia, hyperoxia and hyperoxic hypercapnia, respectively. Parametrical T2* relaxation time maps were computed, average T2* values were derived from Region-of-Interest analysis by two independent and blinded readers in 16 standard myocardial segments on 3 short axis slices per patient. Results: Inter-and intra-reader correlations of T2* measurements were good (ICC=0.75 and ICC=0.79, both P < 0.001). Under normoxia, the mean T2* values were 30.6+7.0 ms at 1.5 T and 27.6+7.6 ms at 3.0 T. Both hyperoxic gases induced significant (P < 0.001) relaxation time increases ΔT2* (oxygen: 1.5 T, 3.5+5.9 ms; 3.0 T, 2.1+6.3 ms; carbogen: 1.5 T, 2.9+7.1 ms; 3.0 T, 4.3+7.6sm). As opposed to 1.5 T, the magnitude of ΔT2* response was higher at 3.0 T and under carbogen as compared with oxygen breathing (p < 0.01). The myocardial ΔT2* response to hyperoxic respiratory challenge can reliably be quantified with BOLD CMR. The magnitude T2* increases significantly with a higher field strength as well as with carbogen as compared to oxygen breathing. Future studies are warranted to investigate the potential diagnostic role of BOLD response in assessing patients with coronary cardiomyopathy. We retrospectively reviewed the imaging features and enhancement pattern of the selectively involved white matter tracts in sixteen (16) genetically proven cases of leukodystrophy with brainstem and spinal cord involvement and elevated brain lactate (LBSL). All patients were presented with slow progressive cerebellar sensory ataxia with spasticity and dorsal column dysfunction. MRI of the brain and spine and MRS of the brain were done to all patients. Results: In all cases, MRI showed signal abnormalities in the sensory and pyramidal white matter tracts in addition to inhomogeneous signal abnormalities in the periventricular and deep white matter, brain stem, cerebellar connections and dorsal columns of the spinal cord. The subcortical U fibres were spared in all cases. Proton MRS showed consistent elevation of the lactate within the abnormal white matter. In eleven cases, diffusion restriction was found in most of the length of the corticospinal and sensory tracts in addition to involvement of the superior and inferior cerebellar peduncles and the mesencephalic trigeminal tracts. These parts of the white matter tracts also displayed heterogeneous enhancement after gadolinium administration. Purpose: The purpose of this study was to evaluate the role of DTI in assessing cervical spondylotic myelopathy (CSM). We prospectively evaluated 65 Patients with symptomatic CSM. The JOA (Japanese Orthopedic Association) myelopathy score was used to assess the clinical situation, dividing patients into groups with minimum myelopathy (MIM), moderate myelopathy (MOM) and severe myelopathy (SEM). All patients underwent examination on a 3.0 T MRI scanner (Verio, Siemens). DTI of the spinal cord was performed in 30 directions (b-value of 0 and 900). Fractional anisotropy (FA), apparent diffusion coefficients (ADC), Eigenvalues (E1, E2.3) were measured. Results: Mean patient age was 58. 8 y/-12, 2 SD. According to the JOA Classification, 33 patients were classified into the MIM Group and 29 into the MOM and 3 into the SEM Group. Significant differences were seen in ADC (0.9±0.2 vs 1.1±0.2) values and FA (0.7±0.1 vs 0.5±0.1) when comparing normal with pathological levels as well as in E1 (1.9±0.4 vs 2.3±0.4) and E2.3 (0.37±0.24 vs 0.5 ± 0.29), respectively. Significant elevation of ADC and reduction of FA was seen in absolute vertebrostenotic segments. Significant Elevation of E1 and E2.3 were seen in vertebrostenotic segments compared with normal. Conclusion: Our results suggest a high sensitivity of DTI metrics in the assessment of CSM. Significant increases in longitudinal and transverse diffusion were seen in our results which might represent a novel biomarker of CSM. MOLLI was performed at a mid-ventricular slice location pre-and 4-20 min (2 min intervals) post-contrast administration. T1 values of the blood pool and the myocardium were measured for each time point and ECV assessment was based on myocardial ΔR1 assessment (pre and post) in relation to ΔR1 blood pool and incorporation of the haematocrit. Results: While pre-contrast T1 values were similar (p=0.3), post-contrast T1 values were significantly shorter at any measured time point post-injection after gadobutrol application (p < 0.047). Myocardial ECV data though calculated for both agents did not show significant differences (p> 0.21). In addition, ECV data related to both agents did not show any significant differences over the assessed time course of 4-20 min p.i. (p> 0.14, gadobutrol; p> 0.09, gadoterate meglumine). Conclusion: Gadobutrol leads to a significantly higher shortening of myocardial T1 values as compared to gadoterate meglumine. The ECV assessment which is independent of the CA properties can be adequately evaluated as early as 4 min p.i. in normal myocardium. Purpose: Existence of vortical blood flow in the main pulmonary artery as diagnostic criterion for diagnosis of pulmonary hypertension was analysed in 3-dimensional (3D) vector field and streamline representations. Methods and Materials: 50 subjects with known or suspected pulmonary hypertension (23 patients with and 27 without pulmonary hypertension, age 58±13 years) underwent right heart catheterisation and time-resolved, 3D phase contrast imaging of the main pulmonary artery. Blood flow patterns were visualised as 3D velocity vector fields projected on 2-dimensional anatomical images (3D-vectors) and as 3D streamlines using 4D-Flow software (Siemens). Relative period of existence of vortical blood flow within the cardiac cycle (tvortex) was evaluated. Comparison of methods for using tvortex as diagnostic criterion for pulmonary hypertension was performed by receiver operating characteristic analysis. Results: Areas under the curve for diagnosis of pulmonary hypertension did not differ significantly (p=0.30) and were 0.998 (95%-confidence interval 0.983 to 1.000) in case 3D-vector vortex detection and 0.991 (95%-confidence interval 0.948 to 0.999) in case of streamline vortex detection. The optimal tvortex cut-off value maximising sum of sensitivity and specificity was tvortex=0.15 for both visualisations. Resulting 95%-confidence intervals for sensitivity and specificity were 0.86 to 1.00 and 0.82 to 0.99 in case 3D-vector vortex detection and 0.79 to 0.99 and 0.82 to 0.99 in case 3D streamline vortex detection. Conclusion: Main pulmonary artery blood flow patterns provide an accurate tool for the diagnosis of pulmonary hypertension with the optimal tvortex cut-off value 0.15. S35 A C D E F G B Conclusion: Using MBIR significantly reduced the need for vessel-wall boundary corrections compared to other reconstruction algorithms, particularly at the side of calcifications. Thus, MBIR improves the feasibility of automated plaque assessment in CCTA and potentially its clinical applicability. Calcium score of small coronary calcifications on multi detector computed tomography: a phantom study J.M. Groen 1 , K.F. Kofoed 2 , M. Zacho 2 , R. Vliegenthart 1 , T.P. Willems 1 , M.J.W. Greuter 1 ; 1 Groningen/NL, 2 Copenhagen/DK (m.j.w.greuter@umcg.nl) Purpose: To assess the feasibility of a new phantom which enables establishment of a calcium scoring protocol for multidetector computed tomography (MDCT) that yields calcium scores comparable to electron beam tomography (EBT) values and to physical mass. Methods and Materials: A phantom containing 100 small calcifications ranging 0.5-2.0 mm was scanned on EBT using a standard coronary calcium protocol, and on a 320-row MDCT scanner using different scanning, reconstruction and scoring parameters (tube voltage 80-135 kV, slice thickness 0.5-3.0 mm, reconstruction kernel FC11-FC15 and scoring threshold 110-150 HU). The Agatston and mass score were compared and the influence of the parameters was assessed. Results: On EBT, the Agatston and mass scores were 0-20, and 0-3 mg, respectively. On MDCT, the Agatston and mass scores were 0-20, and 0-4 mg, respectively. The Agatston score on MDCT differed 52% between 80 and 135 kV, 65% between 0.5 and 3.0 mm and 48% between FC11 and FC15. More calcifications were detected with a lower tube voltage, a smaller slice thickness, a sharper kernel and a lower threshold. An acquisition protocol with 100 kV and two reconstructions protocols could be defined. This protocol yielded Agatston scores as close to EBT as possible, as well as mass scores as close to physical mass as possible. Purpose: Τo report 1-year results of a prospective randomised controlled trial investigating angioplasty with paclitaxel-coated balloons (PCB) versus plain balloon angioplasty for the treatment of failing arteriovenous dialysis access either a fistula (AVF) or a graft (AVG). This was a non-inferiority hypothesis trial registered in clinicaltrials.gov (NCT01174472). Enrollment criteria included an angiographic and clinical diagnosis of dysfunctional dialysis access due to at least one stenotic lesion in patients with AVF or AVG circuits. Forty patients were randomised to undergo either PCB dilatation (n=20) or standard PTA (n=20) of a venous outflow stenotic lesion. Regular angiographic follow-up was scheduled every 2 months. Study primary endpoints included technical success (defined as residual stenosis of the treated lesion > 30% without any significant dissection) and 1-year primary patency of the treated site (defined as angiographic visualisation of a patent lesion with < 50% restenosis and no need for any additional repeat procedure within the previously treated lesion due to failing access). Results: Baseline variables were comparably distributed among the two groups. Technical success was 100% for both groups. Additional post-dilation with a highpressure balloon was necessary in 11/20 (55%) of the PCB-treated cases. At 1 year, cumulative target lesion primary patency was significantly higher after PCB application (35% in PCB group versus 5% in PBA group, p < 0.001, HR (95%CI) = 0.27 (0.13-0.58)). Conclusion: PCB angioplasty might have a place in our quiver for the treatment of stenotic venous outflow lesions of failing dialysis access. for better trade-off of high temporal resolution, less noise and streak artefacts. This is combined with an automatic segmentation and suppression of catheter-induced streaks. This preliminary study included 5 in vivo porcine models. Images were evaluated by experienced cardiologists with respect to noise, temporal resolution and artefact susceptibility. Results: An enhancement of temporal resolution was shown by a decreased fullwidth at half maximum of catheter cross sections using SR 4D-FD-CT as compared to static reconstructions. Motion-map-processing of individual phases increased the contrast-to-noise ratio for each heart phase, e.g. in the left ventricle by an average of 30%. Visual impression confirmed a significant streak reduction. Conclusion: First results show the potential of SR 4D-FD-CT for pragmatic 4Dinterventional imaging. SR 4D-FD-CT allows for dynamic segmentation of cardiac chambers and valves. Purpose: For quantitative measurement of left ventricular myocardial perfusion, stability of HU-values in Dynamic CT-scans is essential. A phantom study is used to evaluate this stability over slices and time using the Philips iCT256-slice scanner. Methods and Materials: Seven time series of CT-images with 11 slices (5 mm) over 30 seconds of a CATPHAN phantom were acquired using the iCT256 at 100 kVp/100 mAs. Six different regions of interest (ROI) were placed into the water regions of the phantom for all slices and time steps. Five ROIs were arranged in a star-like pattern in order to enable evaluation of intra slice variability. One ROI covered the entire water-region. Stability over time and slices as well as within each slice was statistically examined. The absolute difference in the mean values of the entire water ROI in all seven phantom studies was maximum 5.4 HU. The examination of the inter-slice variability revealed a drift of maximal 0.057 HU/slice. Over time, a maximal drift of 0.043 HU/s could be observed. The maximum intra-slice difference of the mean values was at 7 HU. This slightly higher value is due to beam hardening artefacts in the ROIs close to the high-density /bone simulating/ structure in the phantom. Purpose: To evaluate the impact of iterative image reconstruction algorithms including adaptive statistical (ASIR) and model based (MBIR) on the feasibility of automated plaque assessment in coronary computed tomography angiography (CCTA) as compared to filtered-back-projection (FBP) reconstructed algorithm. Methods and Materials: Three ex-vivo human hearts were imaged by CCTA and reconstructed with FBP, ASIR and MBIR. An automated plaque quantification software (Vitrea Cardiac Solutions, MN) was applied for each of the algorithms to fit the outer and inner vessel-wall boundaries. Each coronary cross section, in which the automated software detected wrongly the boundaries, was corrected in a random and blinded fashion. The percentages of corrections were compared between the reconstruction algorithms using Chi-square-test. Results: A total of 2295 CCTA cross sections with 0.5 mm increments were assessed which equals to 765 co-registered triplets (FBP/ASIR/MBIR). Any boundary corrections were performed in a total of 712 cross sections (31.0%), including outer (N=400) and inner (N=381) vessel-wall. The percentage of corrected cross sections was lower for MBIR (24.1%) as compared to ASIR (32.4%, p=0.0003) and FBP (36.6%, p < 0.0001), and marginal between ASIR and FBP (p=0.09). Regional agreement of performed corrections existed between reconstruction algorithms (kappa=0.53). The benefit of MBIR above FBP was associated to the presence of moderate and severe calcification (OR: 2.9 and 5.7, p < 0.0001, respectively). were reviewed to classify arterial involvement according to: 1) TASC II, 2) Graziani's morphological classification, 3) Joint Vascular Society Council calf and foot scores. Clinical results (healing, non-healing, major amputation) were compared to baseline clinical data and angiographic results. Results: 202 percutaneous procedures were performed; the immediate technical success rate was 93.6%. Preprocedurally, the mean±SD calf and foot scores were 7.8±1.6 and 7.3±2.3, respectively; 132 patients (65.3%) were in Graziani's morphological classes 4 to 7; in 112 (55.4%) cases TASC II was inapplicable, for the absence of femoro-popliteal lesions. Post-procedurally, mean calf and foot scores were 4.8±2.3 and 5.9±2.6, respectively, and 86.6% of cases were into the Graziani's classes 1 and 2, whereas TASC II was inapplicable in all cases. Healing and major amputation rates were 66.8% and 3.9%, respectively; only pre-and post-procedural foot scores were significantly associated with the clinical outcome (P <.05). Conclusion: Endoluminal revascularization represents a valuable treatment option in diabetic patients with CLI. In this population, TASC II is inadequate to describe peripheral arterial involvement. Pre-and post-procedural foot scores represent the most significant angiographic parameter to evaluate treatment success, thus aggressive treatment of foot arteries should be attempted whenever possible. 12 months results of a randomised trial comparing mono-or dual-antiplatelet therapy in interventionally treated patients with peripheral arterial disease F.F. Strobl 1 , J. Schmehl 2 , K. Brechtel 2 , T. Zeller 3 , C.D. Claussen 2 , G. Purpose: In this trial, peri-and postinterventional dual antiplatelet therapy significantly reduced rate of target lesion revascularisation after 6 months. It is not known whether this effect persists after stopping clopidogrel. Thus, we conducted an additional follow-up after 12 months. In this double-blinded, randomised trial, we enrolled 80 patients who were treated with PTA or stenting in the upper leg. 40 patients received pre-and postinterventional dual therapy with aspirin and clopidogrel. The other 40 patients received same doses of aspirin and placebo instead of clopidogrel. Clopidogrel/placebo was stopped after 6 months and patients remained on aspirin only. TLR and mortality rate were reevaluated 12 months after the intervention. Results: We initially enrolled 80 patients (42 male, 70±10y), 40 in each group in the study. 12 months after the intervention, 36 clopidogrel and 37 placebo patients could be reevaluated. At 6 months, clopidogrel patients had significantly lower rates of TLR compared to placebo patients: 2 (5%) vs.8 (20%), p=0.04. After stopping clopidogrel/placebo, there was no more significant difference in TLR 12 months after study inclusion with 9 (25%) clopidogrel vs.12 (32.4%) placebo patients (p=0.35). Mortality was 0 vs. 1 at 6 months (p=0.32) and 0 vs. 3 at 12 months (p=0.08). Conclusion: In contrast to the first follow-up 6 months after the intervention according reduction of TLR, this advantage of dual antiplatelet therapy does not persist after stopping clopidogrel. Prolonged dual therapy (> 6 months) should be evaluated and considered in patients with high risk for restenosis. Comparing 2D angiography, 3D rotational angiography, and preprocedural CT image fusion with 2D fluoroscopy for endovascular repair of thoraco-abdominal aortic aneurysm V. Tacher 1 , M. Lin 2 , P. Desgranges 1 , T. Grünhagen 3 , A. Luciani 1 , J.-P. Becquemin 1 , J.-F. Deux 1 , A. Rahmouni 1 ; 1 Creteil/FR, 2 Briarcliff Manor, NY/US, 3 Best/NL Purpose: To evaluate the feasibility of pre-procedural arterial phase computed tomography image fusion with intra-procedural fluoroscopy (or Image fusion: IF) road-mapping in endovascular repair of thoraco-abdominal aortic aneurysm (EVR-TAAA) compared to current road-mapping methods (2D and 3D angiographies) in terms of x-ray exposure, injected contrast volume, and procedure time. Methods and Materials: Single-institution prospective study (Internal institute approved), on 37 patients, informed written consent provided, and treated for EVRTAAA. All interventions were performed on the same angiographic system. Patients were consecutively placed in three groups in a seven-month period: "2D angiography" (2DA) (9 patients), "3D rotational angiography" (3DA) (14 patients) and "image fusion" (IF) (14 patients). Injected contrast volume, x-ray exposure (dose-area-product: DAP) and procedure time were recorded. To compare the groups in terms of the above measures and general patient characteristics, statistical tests using Fisher's Exact, Kruskal-Wallis and Mann-Whitney were performed. Results: Patient characteristics and stenting types were similar between all three groups with no statistically significant differences (p-value> 0.05). The IF Lower limb multilevel treatment with drug eluting balloon: 12-month results from the "DEBELLUM" trial F. Fanelli, A. Cannavale, P. Lucatelli, A. Wlderk, C. Cirelli, F.M. Salvatori; Rome/IT (fabrizio.fanelli@uniroma1.it) Purpose: To report 12-month results of the "DEBELLUM"-drug-eluting balloon evaluation for lower limb multilevel treatment-trial performed to evaluate the efficacy of drug-eluting balloon-DEB versus conventional balloon catheter-NCB in the treatment of peripheral arterial disease. Methods and Materials: Fifty consecutive patients (mean age 67±21 years) with symptomatic peripheral arterial disease were randomised between DEB (25 patients-57 lesions) (Inpact®-Medtronic) and NCB (25 patients-65 lesions). Inclusion criteria were native single or multiple stenosis or occlusion (mean lesion length 7.5 ± 3.5 cm) in the femoro-popliteal or below the knee (BTK) regions. Dilatation was performed in each group either for native lesions (26 DEB; 30 NCB) or post-stent implantation (31 DEB; 35 NCB). Primary end points were late lumen loss (LLL) at 6 and 12 months. Secondary end-points were target lesion revascularisation (TLR), amputation and thrombosis rate. Results: One-hundred-twenty-two lesions were treated: 75.4% in the femoropopliteal area; 24.6% BTK; 21.3% total occlusions. LLL was 0.5±1.4 mm (DEB) vs. 1.6±0.7 mm (NCB) (p < 0.01) at 6 months and 0.64±0.9 mm (DEB) vs. Purpose: This study aimed at assessing retrospectively the middle-term clinical outcome of the femoropopliteal chronic total occlusion (CTOs) treatment by means of directional atherectomy (DA). Methods and Materials: Between January 2008 and March 2012, 47 patients (51 limbs, patient age 70±10 years) were included in the study with mean follow-up of 20 months (6-51). 51 femoro-popliteal CTO in 47 Patients with severe intermittent claudication (N=15; 49.4%) or critical limb ischaemia (CLI) (N=16; 51.6%) were treated with SilverHawk or TurboHawk atherectomy followed by angioplasty in 10 (32.2%) cases. Clinical and USCD follow-up was set at 3, 6 and 12 months and yearly thereafter. Immediate technical success, disease-free patient survival and target lesion revascularisation (TLR) rates were assessed with Kaplan-Meier analysis. Results: Technical success rate was 98% with a lesion length of 80±56 mm. Limbsalvage and survival rates were 87.5 and 90.3% at 2 years, respectively. At 6, 12 and 24 months disease-free patient survival was 88.7, 79.9 and 64.6%. Whereas adjunctive PTA was performed in 32% cases to improve the angiographic result, 12% required an associated tibial vessel treatment. No perioperative mortality was observed. One complication (2%) occurred. Conclusion: Percutaneous directional atherectomy is a safe and effective technique in lower limb revascularisation. Preliminary results supported by short-mid term data encourage use of DA with SilverHawk and TurboHawk catheter in the femoro-popliteal obstructive lesions also in traditionally "forbidden districts". Longterm data are missing. Predictive value of angiographic scores for the integrated management of the ischaemic diabetic foot Purpose: Treatment of lumbar artery fed type 2 endoleaks (lafT2E) after abdominal endovascular aneurysm repair (aEVAR) exhibits high failure and recurrency rates. We report our preliminary results of CT-guided direct sac puncture, followed by embolisation with the liquid embolic agent ethylene vinyl alcohol copolymer (Onyx®). Methods and Materials: 17 male patients (mean age 76 ±6 yrs) with lafT2E were included after failure of conservative treatment. All received CT guided direct sac puncture under local anaesthesia, followed by CT fluoroscopic embolisation with Onyx 34® or 20®. Follow-up examination included contrast-enhanced ultrasound (CEUS) and dual-phase CT angiography every 6 months for at least 2 years (ongoing). Results: Technical success was achieved in all cases, requiring dual puncture of the aneurysm sac in 8 cases (47.1%). Average duration of the procedure was 60 ± 12 min. In mean 7.5 ml of Onyx 34® were used per procedure. In 6 cases Onyx 20® was additionally used for complete filling of the endoleak. Repeat intervention was necessary in 3 cases (17.3%) due to new endoleak development in the follow-up period of 12 ± 8 months. The procedure failed permanently in 1 case. Complications such as major bleeding, spinal ischaemia or non-target embolisations were not observed. Conclusion: Completely CT-guided treatment of lafT2E is a feasible and safe treatment alternative. Difficulties lay in the determination of the necessary amount of Onyx and the end point of the intervention. Several punctures as well as repeat intervention might be necessary to achieve permanent endoleak occlusion. Purpose: Treatment of type 1 endoleaks after endovascular aneurysm repair (EVAR) can be challenging. We describe a technique for direct embolisation with the liquid embolic agent ethylene vinyl alcohol copolymer Onyx by direct catheter access to the endoleak, and present first results. Methods and Materials: 18 patients (16 male, 2 female, mean age 72 +-7 yrs) with a type 1a (n = 13) or a type 1b (n = 5) endoleak were treated. In 13 cases, it was applied as stand-alone procedure, and in 5 cases in combination with stent graft extension. Access was trans-brachial for type 1a endoleaks, and trans-inguinal for type 1b endoleaks. A multi-purpose catheter was placed between the aortic wall and the stent graft to access the endoleak, followed by coaxial introduction of a dimethyl sulfoxide (DMSO) compatible micro-catheter into the endoleak, and consecutive Onyx embolisation. Results: Technical success was achieved in all cases. A mean volume of 11 ml +-5 ml of Onyx 34 was used. In 5 cases, additional coils were used as an anchor for Onyx. 1 patient developed reperfusion of the endoleak during follow-up of 12 +-8 months, which was successfully treated with the same technique. Non-target embolisation, catheter encasement, or anaphylactic reactions to DMSO were not observed. The described technique is feasible, safe, and effective for treatment of type 1a and 1b endoleaks with excellent technical success rates, and low relapse rates. It can be used as stand-alone procedure or easily be combined with stent graft extension. Conclusion: Image fusion road-mapping for EVRTAAA is feasible and is associated to a statistically significant reduction in contrast volume and a trend towards DAP reduction while maintaining similar procedure time. The medium term follow-up was 24 months. Cross-tabulations were checked with chi-squared test, or by Fisher's exact test. Survivorships were analysed by Kaplan-Meyer product limit method and by Cox semiparametric regression. Results: Technical success was achieved in 98.7%. 14/77 presented endoleaks during the follow-up (type 1=7, type 2=6 and type 3=1). During the follow-up there were 7 mortalities, mean time 19.82 months (range 3-48). In survival rates there was no difference between hybrid procedures group (p=0.3387) and elective or emergency group (p=0.3608). There was a statistical difference on survival between the group that had endoleaks during the follow-up (p=0.0093) and who had had necessity of a second endovascular interventional (p=0.0184). Statistical difference on survival was also seen between patients who developed type 1 and 2 endoleaks (p=0.0336). Conclusion: TEVAR is a safe and effective treatment. The presence of endoleak, special type 1 and the necessity of a second endovascular intervention reduces significantly the survival. Selective coverage of the left subclavian artery without recanalization in patients with patent vertebro-vertebral arterial communications during TEVAR: a single centre study M. Lee; Seoul/KR (eterna0@yuhs.ac) Purpose: To evaluate the safety and effectiveness of selective coverage of the left subclavian artery (LSCA) without recanalization during TEVAR in patients with patent vertebro-vertebral arterial communications and to assess morphologic change of the vertebral artery (VA) after the procedure. Methods and Materials: Among 126 patients who underwent TEVAR, 29 patients requiring LSCA coverage without pre-emptive recanalization were retrospectively analysed. The patients' ages ranged from 45 to 84 years. Vertebro-vertebral arterial communications in all patients were evaluated by contrast-enhanced computed tomography (CECT), time-of flight magnetic resonance angiography, or conventional angiography. Neurologic complications such as spinal cord ischaemia (SCI) or cerebrovascular accidents (CVA) were analysed. Pre-and post-procedural changes in VAs were evaluated on follow-up CECT. The overall 30-day mortality was 6.9% (2/29). None of the patients had an SCI or stroke of posterior circulation alone. CVA from embolic infarctions occurred in two patients (7.4%). Transient left arm ischaemic symptoms were present in 5 patients (18.5%), but none required secondary interventions. Delayed development of type I endoleak occurred due to stent deformity in one patient, who underwent surgery. One patient required re-intervention after a pseudoaneurysm developed at the distal margin of the previously placed stent-graft at ten-month follow-up CECT. Hypertrophy of the right VA after TEVAR was seen in 7 of 27 patients (25.9%); two patients showed bilateral hypertrophy of VAs. Conclusion: LSCA coverage without recanalization can be safely performed during TEVAR in patients with patent vertebro-vertebral communications. Hypertrophy of the right VA was noted in 25.9% of patients after LSCA coverage. Purpose: Double-bundle reconstruction with stump preservation has revolutionised the surgical treatment for anterior cruciate ligament (ACL) injury. However, poor revascularization at the osteoligamentous interface (OI) of the tibia tunnel remains a major cause of graft complications. In this study, we applied dynamic contrastenhanced (CE) magnetic resonance imaging (MRI) to quantify the OI enhancement values of the tibia tunnels and ACL stump. We aimed to determine the relationship between graft complications and OI and stump enhancements. Methods and Materials: From October 2011 to April 2012, 34 patients were enrolled in our study (mean postoperative duration, 7.3 months). All patients underwent one 1.5-T MRI study with the imaging pulse-sequence protocol of proton density-weighted imaging (WI), T2WI, pre-enhanced and post-enhanced T1WI, and dynamic CE MRI. Graft complications, including cystic degeneration and tear, were evaluated using pre-enhanced MRI, and peak enhancement (ePeak) values were acquired from a dynamic CE study. The receiver operating characteristic (ROC) analysis was used to obtain optimal cut-off values for complicated grafts. Results: Our study included 28 patients (mean age, 25.5 years). Nine patients (32.1%) had cystic degeneration and 1 (3.6%) had complete posterolateral (PL) bundle tear. Mean ePeak percentages for graft with or without complications were 84.19%/127.69% for anterior--medial (AM) bundle, 107.54%/128.21% for PL bundle, and 171%/151.06% for stump, respectively. ROC analysis yielded the optimal ePeak cut-off values of 126%, 104%, and 35% for AM bundle, PL bundle, and stump, respectively. Conclusion: Graft complications were directly associated with higher tibial OI values but inversely associated with higher stump values. Purpose: To test if the posterior cruciate ligament (PCL) index is predictive of rotational knee kinematics during pivoting activities and anterior tibial translation (ATT) in patients after anatomic single-bundle (SB) anterior cruciate ligament reconstruction (ACLR). Sixteen patients with SB-ACLR were prospectively evaluated with 3D-motion analysis during (1) descending and pivoting, and (2) landing and pivoting. The side-to-side difference of tibial rotation range of motion (SSDTR) between the ACLR and the contralateral intact knee was calculated. ATT SSD was measured with a KT-1000 arthrometer. MRI was used to measure the PCL index for the study group and a control group. Linear regression models were used with PCL index as predictor of SSDTR for each task and side to side anterior translation differences. Unpaired sample t-test was used to compare PCL index group means between the study and control group. The level of significance was set at α=0.05. Results: PCL index of the ACLR knee was significantly lower compared to the healthy control knee (p < 0.001). The PCL index was predictive of low SSDTR during pivoting after descending and landing tasks (R2=0.472, p=0.003 and R2=0.477, p=0.003 respectively). PCL index was not predictive of ATT with 134 N or maximum manual force (R2=0.13, p=0.17 and R2=0.009, p=0.726 respectively). The PCL index after anatomic SB ACLR is predictive of rotational kinematics during dynamic pivoting activities. These results suggest that after anatomical ACLR the PCL index can serve as an indicator of tibial-femoral position and may predict dynamic tibial rotation. Microstructural evaluation of the cruciate ligaments with MR diffusion tensor imaging (DTI): correlations with knee stability L. Di Clemente 1 , D. Tortora 1 , V. Panara 1 , M. Savastano 1 , V. Calvisi 2 , P. Palumbo 2 , A. Tartaro 1 , A.R. Cotroneo 1 , M. Caulo 1 ; 1 Chieti/IT, 2 L'Aquila/ IT (lorisdiclemente@gmail.com) Purpose: The evaluation of knee stability is currently based on tibio-femoral sagittal plane motion measurement as evaluated using the KT-1000 arthrometer. Conventional MRI cannot evaluate knee stability. The aim of the study was to assess the use of MR-Diffusion Tensor Imaging (DTI) as a tool for a microstructural examination of the anterior and posterior cruciate ligaments and to correlate DTI finding with clinically evaluated stability. Methods and Materials: 11 subjects (6 females) without previous history of knee injuries underwent MRI using conventional and DTI sequences. Fractional anisotropy (FA) values were calculated in each anterior and posterior cruciate ligament within 3 different ROIs placed in the lower, middle and upper portion of the ligaments. Knee stability was assessed using KT-1000 arthrometer in 4 progressive active displacements: 15 lbs, 20 lbs, manual maximum displacement and under quadricipital muscle contraction. Statistical analysis was performed using Independent t-Test and Kendall tau rank correlation test, where appropriate (p < 0.05). Results: FAs of the ACL (mean: 0.573±0.047) were significantly lower compared with the PCL (mean: 0.676±0.046) (p < 0.001), whereas no side differences were noted. A significant negative correlation between FA and KT-1000 arthrometer values at 15 lbs was present in the PCL (r=-0.341; p=0.029). No correlations were observed between the FA and KT-1000 values in the ACL. Conclusion: Functional assessment of the microstructural organisation of the cruciate ligaments with DTI expands MRI applications beyond simple morphological studies and could help bridge the gap between imaging and clinical evaluation of knee stability. The Schatzker classification for tibial plateau fractures and the amount of articular depression were assessed using MDCT. Magnetic resonance images were evaluated for crucial and collateral ligament injury, meniscal tears and patellar retinaculum lesions. Statistics included logistic regression and analysis of covariance. Results: Associated soft-tissue injuries were identified in 82% of the patients. Logistic regressions revealed a significant impact of increasing amounts of tibial plateau fracture depression on the incidence of meniscus lateralis tears (P = 0.025) and lesions of the anterior cruciate ligament (P = 0.018). Analysis of covariance demonstrated a significant correlation between the amount of articular depression and the absolute number of soft-tissue injuries (P = 0.001). Conclusion: Articular depression is a potential predictor of specific meniscal and ligamentous injuries in acute tibial plateau fracture. Due to the high incidence of associated soft-tissue lesions, magnetic resonance imaging is generally recommended, especially in cases with distinct tibial plateau fracture depression at MDCT imaging. Anatomical risk factors in patients after patellar dislocation: a casecontrol study using MRI T. Köhlitz, S. Scheffler, T. Jung, E. Wiener, B. Vollnberg, G. Diederichs; Berlin/ DE (bernd.vollnberg@charite.de) Purpose: To assess anatomical risk factors in patients after lateral patellar dislocation (LPD) and controls using MRI. Methods and Materials: MR images of 186 knees after LPD and of 186 age-and gender-matched controls were analysed. The presence of trochlear dysplasia was assessed by evaluation of trochlear inclination, facet asymmetry, and trochlear depth; patella alta was evaluated by Insall-Salvati-index and Caton-Deschampsindex; and lateralized force vector was measured by the tibial tuberosity-trochlear groove (TT-TG) distance. Results: Compared with controls, dislocators had significantly lower values for all three parameters of trochlear dysplasia (-32%, -32%, -44%) and significantly higher values for patella alta (+14%, +13%) and TT-TG (+49%) (all P < 0.001). Trochlear dysplasia was observed in 112 dislocators (66%), of whom 61 (36%) additionally had patella alta and 15 (9%) an abnormal TT-TG. As isolated risk factors, patella alta (15%) and abnormal TT-TG (1%) were rare. Only 25 dislocators (15%) had no anatomical risk factor. Trochlear dysplasia in conjunction with abnormal TT-TG or patella alta is associated with a 37-fold and 41-fold higher risk. Conclusion: Most dislocators have anatomical risk factors, varying in severity and constellation. Trochlear dysplasia is the main risk factor for LPD, while patellar alta and abnormal tibial tuberosity-trochlear groove distance may be additional factors. Patient-specific evaluation of risk factors following LPD may help future management. Early changes of trabecular bone structure in asymptomatic subjects with knee malalignment T. Baum, J. Penzel, M. Sauerschnig, E.J. Rummeny, K. Wörtler, J.S. Bauer; Munich/ DE (thbaum@gmx.de) Purpose: Knee malalignment is a risk factor for knee osteoarthritis (OA). The purpose of this study was to investigate whether alterations of trabecular bone structure can already be found in young, asymptomatic subjects with knee malalignment. Methods and Materials: Forty-eight asymptomatic subjects (25 females, 23 males; age: 26±2years) without history of knee injury or surgery were included in this study. Based on MR measurements, knee joint alignment of both lower extremities was assessed and subjects were divided into four groups (each including 12 subjects, i.e. 24 knees): neutral (up to 1° varus/valgus), mild varus (2°-4°), severe varus (greater 4°), and valgus (2°-4°). A T1-weighted 3D-FLASH sequence (spatial resolution: 0.25x0.25x1.2 mm³) was obtained of each knee at 1.5 T to determine histomorphometric and texture parameters of the trabecular bone in the medial/ lateral femur/tibia (MF,LF,MT,LT). The calculated parameters were compared between the four groups in each compartment using ANOVA including Bonferroni correction for multiple comparisons. Purpose: We performed a randomised, double blinded, placebo controlled study to assess the effectiveness of LLLT in patients with knee pain related to meniscal pathology. The study trial number is ISRCTN24203769. We only included symptomatic patients with tiny focus of Grade 3 attenuation (seen only on 0.7 thickness sequences) or intrasubstance tears with spot of Grade 3 signal intensity approaching the articular surface. None of the patients in the study group underwent arthroscopy or new MRI investigation. A paired samples t-test was used to detect significant changes in subjective knee pain over the experimental period within groups, and ANOVA was used to detect any significant differences between the two groups. Results: Pain was significantly improved for the LLLT group than for the placebo group (F=154, p < 0.0001). Pain scores were significantly better after LLLT. Four (12.5%) patients did not respond to LLLT. At baseline, the average Lysholm score was 77 ± 4.6 for the LLLT group, and 77.2 ± 2.6 for the placebo group [p> 0.05]. Four weeks after LLLT or placebo therapy, the laser group reported an average Lysholm score of 82.5 ± 4.6, the placebo group scored 79.0 ± 1.9. At 6 months, the laser group had an average Lysholm score of 82.2 ± 5.7, an after one year they scored 81.6 ± 6.6 (F=14.82923, p=0.002). Treatment with LLLT was associated with a significant decrease of symptoms compared to placebo. In patients with small meniscal tears who do not wish to undergo surgery, LLLT should be considered as a non-invasive alternative. is not clear, i.e. whether meniscal injury leads to cartilage degeneration or vice versa. Therefore, we aimed to evaluate the impact of meniscal tears on adjacent, morphologically intact knee cartilage using T2 relaxation time, a sensitive biomarker for early cartilage degeneration, and compare with healthy controls. Methods and Materials: Sixty-nine subjects without evidence of OA were recruited from the Osteoarthritis Initiative. Thirty-five Subjects (26-women) with a normal medial meniscus were used as controls (age 61±8, BMI 27±5). Thirty-four subjects (20-women) had either a simple (non-displaced tear; n=19, age 61±9, BMI 28±5) or complex tear (displaced tear; n=15, age 60±9, BMI 29±5) of the posterior horn of the medial meniscus. None of the tear-subjects had morphological lesions of the medial tibio-femoral cartilage. T2-measurements were performed in the whole medial tibia (MT) and the medial femur compartments (MF), and in tibio-femoral subregions adjacent to the torn meniscus (sMT & sMF). Multiple linear-regression models were used to compare mean T2-values of individuals with meniscal tears with normal controls. Purpose: Patients with good or complete response after neoadjuvant chemoradiation have excellent long-term outcome. Minimal invasive treatment (i.e. transanal endoscopic microsurgery (TEM) and wait-and-see policy) are increasingly considered as an alternative to major surgery. With this prospective cohort study we aimed to evaluate long-term outcome of strictly MR-based selected patients who have been treated with minimal invasive treatment. Methods and Materials: Eight weeks after chemoradiation, endoscopy and restaging MRI were performed (including diffusion-weighted MRI for yT-staging and gadofosveset-enhanced MRI for yN-staging). Complete responders were selected for wait-and-see policy and good responders with small tumour remnant for TEM. Both treatment groups underwent intensive 3-to-6 monthly follow-up, using MR imaging (DWI+gadofosveset), CEA, CT of thorax and abdomen and endoscopy was performed. Long-term outcome was estimated with Kaplan-Meier curves. Results: Forty-one patients were included, thirty-three in the wait-and-see group and eight in the TEM-group. Mean follow-up was 26 months (range 6-91). For the TEM-group, 4 patients had ypT0 and 4 had ypT2. Two patients, both in the wait-and-see group, developed a local recurrence within two years and underwent surgery, leading to a 2-year local recurrence rate of 9%. Both recurrences were detected on (DWI-)MRI in an early stage. The cumulative probabilities of 2-year disease-free survival and overall survival were 93% and 100%, respectively. No recurrences occurred in the TEM-group. Conclusion: Both selection and follow-up of good and complete responders after chemoradiation for rectal cancer with MRI is feasible. Long-term outcome so far is excellent. (DWI-)MRI seems to be a reliable tool for early recurrence detection. Diffusion-weighted-based volumetry in the assessment of response in patients with rectal cancer treated with neo-adjuvant therapy: feasibility study S.F. Carbone, M. Palumbo, V. Ricci, L. Pelliccia, E. Cacchiarelli, L. Volterrani; Siena/IT (fracarb@gmail.com) Purpose: To establish the reproducibility of volumetric magnetic resonance diffusion (VDWI) and compare it with the conventional volume (VC) in the assessment of response in patients with rectal cancer treated with chemoradiotherapy (CRT). We retrospectively examined 21 patients (mean age 68.9 years) with rectal cancer who have performed MRI before and after 45 ± 15 days of the CRT after undergoing anterior resection of the rectum. After surgery, ypTN and TRG (tumour regression grading) according to Mandard classification were obtained. We considered patients with TRG 1-2 responder and non-responder patients with TRG 3-5. Two radiologists, blinded, have extrapolated the volume VC and VDWI lesions pre-and post-CRT. The inter-observer agreement and the agreement between Vc and VDWI pre-and post-CRT were calculated by intraclasscorrelation coefficient (ICC). The inter-observer agreement for VC and VDWI was 0.948 and 0.916 respectively, while the correlation between VC and VDWI investigating pre-CRT was 0.828 and in the post-CRT in 0.151. After CRT, VC shows a correlation with the TRG of rho = 0.154 (p < 0542), while a significant linear relationship was evident between VDWI and TRG with rho = 0556 (p < 0.05). Post-CRT the VDWI shows a significant difference between responders and nonresponders (p = 0.018). The VDWI is a reproducible quantitative technique in assessing the response to CRT in patients with rectal cancer and shows a better correlation with the residue of the disease compared with the VC. Therapy response assessment in locally advanced rectal cancer: comparison between functional dynamic and diffusion parameters in MRI R. Fusco, V. Granata, M. Petrillo, M. Sansone, A. Petrillo; Naples/IT (roberta.fusco@unina.it) Purpose: We investigated the diagnostic performance of DCE-MRI and DW-MRI in evaluating neoadjuvant chemo-radiotherapy (CRT) response in LARC. We compared a semiquantitative dynamic feature, the standardised index of shape (SIS) and the diffusion parameters obtained using intravoxel incoherent method. Purpose: To compare image quality and detection of clinical findings of the new WARP sequence versus conventional optimised MR sequences in patients with total knee arthroplasty (TKA). Methods and Materials: Forty-two patients with TKA underwent 1.5 T MRI in this prospective study. Slice-encoding metal artefact correction (SEMAC), view-angle tilting (VAT), and increased bandwidth were combined by the "WARP"-turbo spin echo sequence. Twenty-four patients underwent CT as a reference standard. Coronal STIR-WARP and sagittal intermediate-weighted (PD) WARP-sequences were compared to standard sequences optimised with high readout bandwidth (STIR-hiBW/PD-hiBW). Signal void was quantified. Qualitative criteria (depiction of anatomy, distortion, blurring, noise) were assessed on a five-point scale (1, no artefacts; 5, severe artefacts) by two readers. Clinical findings (e.g. periprosthetic osteolysis) were noted. A t-test (quantitative data) and a Wilcoxon signed rank test (qualitative data) served for statistics. Results: Signal void areas were smaller for STIR-WARP than STIR-hiBW (mean; 20.1 cm 2 /27.0 cm 2 ), and for PD-WARP than PD-hiBW (14.2 cm 2 /16.5 cm 2 ; p <.001 for all comparisons). Depiction of anatomic structures was better on STIR-WARP versus STIR-hiBW (2.9-3.7 vs. 4.2-4.9; p <.001), and on PD-WARP versus PD-hiBW (2.5-3.5 vs. 3.1-3.8; p <.007). Distortion and image noise were lower for WARP than for the standard sequences (p <.002), while blurring was similar for both techniques. There was a statistically significant advantage for detection of clinical findings for STIR-WARP versus STIR-hiBW (74 and 37 findings; p <.001) and for PD-WARP versus PD-hiBW (63 and 34 findings; p <.001). The WARP sequences showed a statistically significant improvement for most image criteria. Detection of clinically relevant findings was markedly increased. 14:00 Purpose: To determine the diagnostic accuracy of MR in patients with rectal carcinoma by comparing post-chemoradiation MR imaging with pathological specimens. We enrolled 39 patients with a locally advanced rectal cancer. All patients received chemoradiation therapy before surgery. Those patients underwent a neoadjuvant chemoradiation therapy followed by MR scans. The MR images were analysed by a team of two expert radiologists to whom clinical and histo-pathological findings were unknown. Results: Following neoadjuvant chemoradiation therapy, we observed 23 (59%) patients with a rectum disease staged ² T2 and 16 (41%) patients with a disease staged > T2, after MR images analysis. Post-treatment histological staging (TNM) analysis revealed 13 patients with a disease > T2 and 26 patients with a disease ² T2. By arranging the Kappa Cohen test to find the agreement value between post-chemoradiation MR staging and histological response, we found that with a disease confined to the sierosa (² T3) the agreement was 83.6%. We found an agreement of 97.22% between MR and histology for a disease ² N1 and an accord of 33.33% for a disease more advanced than N1 (> N1). Conclusion: MR is critical in discovering a T3 disease; moreover, with morphologic MR Imaging we do not have always the opportunity to discern a few residual cancer cells hidden in the fibrotic tissue that could cause a CRM involvement on histology. Monday fascia infiltration was present on the surgical specimen. In 33 patients reticular (n=18) or linear-shaped (n=15) mesorectal enhancing strands were observed. Reticular-shaped mesorectal enhancing strands were predictors of mesorectal fat infiltration (odds ratio, 7.36; 95% confidence intervals, 1.87-28.98; P < 0.05) but not of mesorectal fascia infiltration (0.86; 0.08-8.87; P=0.9). The enhancing strands reaching the mesorectal fascia represent a predictors of mesorectal fascia infiltration (3.61, 0.99-13.15; P < 0.05). The evidence of enhancing strands reaching the mesorectal fascia represents a predictor of mesorectal fascia infiltration and should suggest to intensify the CRT. Purpose: To show the utility of MDCT assessing the tumour response in locally advanced colon cancer treated with neoadjuvant chemotherapy. Methods and Materials: 22 consecutive patients who underwent this therapy during a 15-month period were included. All tumours were staged before treatment using MDCT 64 or PET-CT scan, and after neoadjuvant treatment other scan was performed by calculating the differences in tumour volumes making use of a dedicated software for semiautomatic volume segmentation, to assess tumour response before surgery. Maximum standard uptake value (SUV max) by PET-CT between the time of initial diagnosis and after neoadjuvant chemotherapy was also measured. Surgical-related complications and oncological outcomes were obtained. Results: Tolerance to chemotherapy was excellent in 86.4% of patients and 95.5% completed the entire chemotherapy initially planned. After neoadjuvant treatment, 69.5% reduction of tumour volume was observed by CT-scan and up to 59.9% decrease of SUVmax (Standard Uptake Value) was achieved by PET/ MDCT. None of the patients showed tumour progression during the preoperative treatment, and all of them underwent the previously planned surgical procedure. Four patients developed postoperative complications. Median time between the end of chemotherapy and surgery was 22 days. Conclusion: Preoperative chemotherapy induces a tumour response that can be measured by imaging methods (MDCT). Assessment of the variation in the contrast-to-noise ratio across a range of CT scanners in a multicentre perfusion CT study of colorectal cancer (PROSpeCT): a phantom study M. Lewis, V.J. Goh; London/UK Purpose: To determine the effect of CT scanner models, iterative reconstruction (IR) and phantom size on CNR of perfusion CT scans. Methods and Materials: A 22-cm diameter water phantom containing different iodine contrast inserts from 2.5 mg/ml to 25 mg/ml was scanned on seven CT scanners from four manufacturers using the Perfusion CT acquisition protocols of a multi-centre clinical trial in colorectal cancer (PROSPeCT). All acquisition protocols employed 100 kV and ~5 mm reconstructed slice. Images were reconstructed with filtered back projection and iterative reconstruction, where available. CT numbers and background noise levels were measured and displayed CTDIvol values noted. A sub-set of measurements was obtained on a 30-cm diameter phantom. The relationship between CT number and iodine density was determined for all datasets and CNR values calculated. Results: A linear relationship between CT number and iodine density was observed, with small variations between CT scanners. No change in linearity was observed with IR of different 'strengths'. CTDIvolvalues varied by a factor > 2. For the lowest density insert, CNR varied from 2.9 to 4.4. With IR, CNR increased by a factor of 1.15 to 2.3 depending on IR'strength'. CNR decreased by ~50% in the 30 cm phantom. The CNR varied by a factor of 1.5 across the range of scanners utilised in this mutlicentre study. The variation was largely due to image noise differences. IR does not affect contrast enhancement and can be used to achieve a given CNR at a reduced dose. Author Disclosures: V.J. Goh: Equipment Support Recipient; Siemens Healthcare, GE Healthcare, TexRAD. Research/Grant Support; NIHR HTA grant. Methods and Materials: 14 consecutive patients with LARC were enrolled. Patients underwent DCE-MRI and DW-MRI (1.5 T, Magnetom Simphony TIM, Siemens, Erlangen). An expert radiologist performed a manual segmentation of the whole lesion on a derived series obtained subtracting the basal and the 5 th post-contrastographic series and on DWI with b value=800. SIS and pure diffusion coefficient, pseudo-diffusion coefficient and perfusion fraction were calculated pixel by pixel. After surgery, tumour regression grade (TRG) was obtained. Patients with TRG 1-2 were considered responders and patients with TRG 3-4-5 were considered non-responders. The value changes of each parameters from baseline to presurgical scan were assessed and correlated with the TRG. Sensitivity, specificity, ROC analysis were applied. Youden Index was used to obtain the optimal cut-off value. Mc-Nemar test was performed to underline statistical difference. Results: Seven patients were classified as responders and 7 as non-responders at histology. The diffusion parameter (fraction perfusion) showed a sensitivity of 100%, specificity of 25% and area under ROC 0.4750 (optimal cut-off value 86.3%); SIS showed a sensitivity of 90%, a specificity of 100% and area under ROC 0.7265 (optimal cut-off value 36.0%). A p value of < 0.05 was obtained comparing SIS vs diffusion parameter. Conclusion: SIS can achieve the best results in discriminating patients responders from non-responders. Reproducibility of MRI texture analysis in primary rectal cancer S. Gourtsoyianni 1 , G. Ljungqvist 1 , A. Khan 2 , R. Glynne-Jones 2 , B. Ganeshan 3 , K. Miles 3 , V. Goh 1 ; 1 London/UK, 2 Northwood/UK, 3 Falmer/UK (sgty76@gmail.com) Purpose: This study aimed at assessing the feasibility and reproducibility of MRI texture analysis in rectal cancer. Methods and Materials: Following IRB approval, 14 patients (11 male, mean 68.3years) with primary rectal cancer underwent two baseline MRIs. T2-W axial sequences were exported for texture analysis (TexRAD, University of Sussex). A Laplacian of Gaussian band-pass filter was applied to highlight different spatial scales (fine (1.0), medium (1.5-2.0) and coarse (2.5) texture). Texture was quantified as entropy (E), uniformity (U), kurtosis (K), skewness (S) and standard deviation of the histogram (SDH) and recorded as for absolute scale values for each tumour. Greater heterogeneity is represented by higher E, greater K, S and SDH and lower uniformity. Overall group median values were recorded and reproducibility (testretest agreement) was assessed using Bland-Altman statistics. Results: All tumours were greater than Stage II; mean length 5.5 cm. Good reproducibility was achieved across all filters (1.0-2.5) for E, U and SDH with mean differences ranging from -0.007 to +0.002 for E; -0.11X10 -3 to + 0.001 X10 -3 for U; and +1.60 to +4.97 for SDH; and within subject coefficients of variation from 2.09-2.55% for E, 10.3-12.7% for U, and 14.3-16.1% for SDH. There was greater variability for K and S: mean differences ranged from +0.168 to + 0.334 for K; and +0.089 to +0.272 for S; within subject coefficients of variation from 31.3-93.7% for K, and 21.5-49.6% for S. Conclusion: MRI texture analysis is feasible in rectal cancer and a reproducible technique in the trial setting. Predictors of mesorectal fascia infiltration on spectral pre-saturation inversion-recovery (SPIR) MR imaging sequence after gadolinium injection in patients with rectal carcinoma after neoadjuvant chemoand radiation therapy E. Quaia, L. De Paoli, A. Gennari, B. Cabibbo, M. Cova; Trieste/IT (quaia@units.it) Purpose: To retrospectively assess the value of spectral pre-saturation inversionrecovery (SPIR) MR imaging sequence after gadolinium injection to identify predictors of mesorectal fat and mesorectal fascia infiltration in patients with locally advanced rectal carcinoma after neoadjuvant chemo-and radiation therapy (CRT). Methods and Materials: Sixty-five consecutive patients (mean age: 68.93 years, range: 48-83 years, M:F 39:26) with locally advanced rectal carcinoma underwent CRT followed by surgery. MR imaging was performed before and after completion of CRT using T2-weighted fast spin-echo and T1-weighted SPIR sequences before and after gadolinium injection. MR images were assessed by two radiologists in consensus. The evidence of reticular (interwoven strands within the mesorectal fat creating a meshwork) or linear-shaped enhancing strands (strands travelling separately through the mesorectal fat) on MR images were retrospectively correlated to the histopathological findings. Results: After CRT the disease was either limited to the rectal wall (n=31 patients) or presented mesorectal fat infiltration (n=34 Conclusion: CEDM has a potential impact on the characterisation of breast lesions. Intensely enhancing lesions are strongly indicative of a malignant nature, yet, overlap of enhancement patterns still exists and therefore further studies with a larger number of studied population are recommended. Clinical feasibility of contrast-enhanced dual-energy mammography (CEDEM) with a tungsten (W)/titanium (Ti) anode/filter combination: a prototype report T. Knogler 1 , R. Leithner 1 , M. Hörnig 2 , F. Semturs 1 , M. Waitzbauer 1 , G. Langs 1 , P. Homolka 1 , K. Pinker-Domenig 1 , T.H. Helbich 1 ; 1 Vienna/AT, 2 Erlangen/ DE (thomas.knogler@meduniwien.ac.at) Purpose: To test the feasibility of CEDEM with a W/Ti anode/filter combination for high energy images in a clinical setting. Methods and Materials: Fifteen female patients with 15 breast lesions were included in this study. CEDEM was performed with a Mammomat Inspiration prototype (Siemens, Germany) before and after i.v. administration of 2-ml Iomeron® 400 (Bracco, Italy) per kg b.w. at a rate of 3.5 ml/sec. Dual-energy images were acquired with 28-32 kVp and a W/Rhodium (Rh) anode/filter combination for lowenergy and 49 kVp and a W/Ti anode filter combination for high energy. Weighted subtraction images were computed for diagnostic work-up. Images were assessed by two readers with respect to lesion-enhancement and image quality. A histological work-up was performed in all lesions. Results: Histopathology revealed eight malignant lesions and seven benign lesions (size range from 8 to 38 mm). All malignant lesions enhanced and were seen from both readers on weighted subtraction images. Benign lesions did not enhance thus they were not visualised on weighted subtraction images. Image quality was rated excellent from both readers. Based on the visibility of the lesion CEDEM allowed an accurate differentiation of benign and malignant breast lesions. Conclusion: CEDEM with a W/Ti anode/filter combination is suitable and feasible. Lesion visibility and image quality were excellent. Further research is needed to determine the value of CEDEM in a clinical setting. Diffusion-weighted-based MRI: volumetry and apparent diffusion coefficient S.F. Carbone, M. Palumbo, T. Carfagno, V. Ricci, L. Pirtoli, L. Volterrani; Siena/IT (fracarb@gmail.com) Purpose: To assess the diagnostic accuracy of volumetric magnetic resonance diffusion (VDWI) and Apparent Diffusion Coefficient (ADC) in the assessment of response in patients with rectal cancer treated with chemoradiotherapy (CRT). We retrospectively examined 30 patients (mean age 68.1 years) with rectal cancer, who have performed MRI before and after 45 ± 15 days of the CRT after undergoing to anterior resection of the rectum. After surgery, ypTN and TRG (tumour regression grading) according to Mandard classification were obtained. We considered responders patients with TRG 1-2 or with a negative follow-up recurrence in the next 12 months (only three cases). Two radiologists, in consensus and using commercial software, have extrapolated pre-and post-CRT VDWI of the lesions and calculated the ADC. Results: The ADC did not show significant differences between responders and not-responders (p = 0.08 pre-CRT, p = 0.1 post-CRT); the VDWI of responders was significantly lower in both pre-CRT (p = 0.0065) and in post-CRT (p = 0.006) compared with not-responders VDWI. The accuracy in the evaluation of response was of 70 and 91%, respectively, for the ADC and VDWI. The VDWI is more reliable than ADC to assess the response to CRT in patients with rectal cancer. Computed tomography of the bowel: a prospective comparison study between four techniques M. Revelli, F. Paparo, L. Bacigalupo, A. Garlaschi, L. Cevasco, E. Biscaldi, G. Rollandi; Genoa/IT Purpose: Our purposes were to compare the grade of bowel distension obtained with four different CT techniques dedicated for examination of small intestine (CT-enteroclysis and CT-enterography), colon (CT with water enema), or both (CT-enterography with water enema) and to assess patient tolerance towards each protocol. We recruited four groups of 30 patients. Each group corresponded to a specific CT technique, for a total of 120 consecutive patients (65 male, 55 female; mean age 51.09±13.36 years). CT studies were evaluated in consensus by two gastrointestinal-dedicated radiologists who performed quantitative and qualitative analysis of bowel distension. Presence and type of adverse effects were recorded. Results: CT-enteroclysis provided the best distension of jejunal loops (median diameter 27 mm; range 17-32 mm) compared with all other techniques (p < 0.0001). Frequency of patients with an adequate distension of the terminal ileum was not significantly different among the four groups (p=0.0608). At both quantitative and qualitative analysis CT with water enema and CT-enterography with water enema determined a greater and more consistent luminal filling of the large intestine compared with the one provided by both CT-enteroclysis and CT-enterography (p < 0.0001 for all colonic segments). Adverse effects were more frequent in patients from the CT-enteroclysis group (p < 0.0028). Conclusion: CT-enteroclysis allows an optimal distension of jejunal loops, but it is the most uncomfortable CT protocol. When performing CT with water enema, an adequate retrograde distension of the terminal ileum was provided in a high percentage of patients. CT-enterography with water enema provides a simultaneous optimal distension of both small and large bowel. S37 C A D E F G B excellent (0.9/0.9), but worse for VEE (0.7/0.6). Correlations of small arbitrary ROIs were lower for all parameters. Conclusion: Perfusion and permeability parameters of DCE-MRI of RCC are influenced by ROI-size and positioning. The best inter-and intraobserver correlation showed definition of whole tumour ROI with morphological sequences or plasma flow maps. Evaluating tumours or monitoring antiangiogenic therapy, perfusion parameters are more reliable, while permeability parameters are more susceptible to interobserver variability. Can a contrast-enhanced ultrasound nephrostogram be used instead of a fluoroscopic nephrostogram: preliminary findings M. Daneshi, K. Patel, D. Huang, M. Sellars, P. Sidhu; London/UK Purpose: The use of contrast-enhanced ultrasound (CEUS) has extended beyond traditional uses, and the possibility to delineate percutaneous tubes and drains is achievable. We have compared the traditional fluoroscopic nephrostogram using iodinated contrast agents with CEUS nephrostogram to ascertain the accuracy, utility and convenience of the CEUS nephrostogram. The standard conventional nephrostogram was performed immediately prior to the CEUS nephrostogram. The CEUS nephrostogram technique involved diluting 0.2 ml of SonoVue with 40 ml of normal saline and introduced into the renal collecting system via the nephrostomy tube. Digital cineclips and still images were recorded to allow accurate retrospective comparison by two independent reviewers to the reference standard. Results: Twelve nephrostomies in 10 patients (median age 64 yrs, range 29-91 yrs, 6 females and 4 males) were performed and reviewed. The renal pelvicalyceal system was visualised in both CEUS and fluoroscopic nephrostograms in 11/12 (92%) with one nephrostomy tube identified as being misplaced. The entire ureter was visualised in 6/12 (50%) with a CEUS nephrostogram compared with 8/12 (75%) using traditional nephrostogram. Fluoroscopic nephrostogram showed drainage of contrast into the bladder in 10/12 (83%) cases compared with 9/12 (75%) using CEUS. Conclusion: Preliminary results suggest that CEUS nephrostogram is a feasible method to confirm the correct positioning of the nephrostomy tube, image the ureters and determine if there is satisfactory drainage into the bladder. CEUS nephrostogram is a suitable alternative for the traditional nephrostogram in patients with contraindications to iodinated contrast agents or if the procedure needs to be performed at the bedside. Vena cava anomalies associated with horseshoe kidney on MDCT T. Ichikawa, J. Koizumi, S. Kawada, Y. Imai; Isehara/JP (tamaki-i@mars.sannet.ne.jp) Purpose: The incidence of vena cava (VC) anomalies in horseshoe kidney (HSK) patients is relatively high because of embryogenesis. We evaluated prevalence and variation of anomalous inferior vena cava (IVC) and superior vena cava (SVC) in HSK patients detected using CT. Methods and Materials: Seventy-one patients with HSK and 2292 patients with normal kidney (NK) who underwent chest CT were evaluated of prevalence and variation of anomalous SVC and 205 patients with HSK and 1990 patients with NK who underwent abdominal CT were evaluated of prevalence and variation of anomalous IVC. We reviewed axial CT images with 5-mm reconstruction interval and compared prevalence of anomalous VC between HSK and NK patients using Chi-square test. Results: Anomalous SVC was identified in 3 patients (4.2%) in HSK patients: 2 double SVCs and 1 persistent left SVC without right SVC and 5 patients (0.22%) in NK patients: 3 double SVCs and 2 persistent left SVC without right SVC. Anomalous IVC was identified in 8 patients (3.9%) in HSK patients: 1 preisthmic IVC with retrocaval ureter, 4 double IVCs, 2 left IVC, and 1 IVC with azygos continuation and 12 patients (0.6%) in NK patients: 8 double IVCs, 3 left IVC, and one IVC with azygos continuation. There was a significantly higher prevalence of anomalous VC in patients with HSK than in those NK on MDCT (P < 0.001). Conclusion: HSK patients were frequently found anomalous VC and detection of those anomalies in HSK patients is important during central venous catheter procedures and operation. or excision biopsy. Qualitative analysis of cine loops was assessed for each CEUS examination by two observers and consensus reached on the pattern and timing of tumour enhancement. Perfusion quantification of the lesions was performed where possible, with time-intensity curves were analysed. Results: Distinct differentiation on enhancement patterns was observed between Leydig cell and germ cell tumours. All 11 Leydig cell tumours displayed intense early enhancement which persisted for longer than the normal testicular parenchymal enhancement. The germ cell tumours showed loss of the normal linear vascular pattern, but with a more rapid washout of contrast. Quantitative analysis confirms the observation, with longer full width at maximum (FWHM) and slower contrast outflow on the time-intensity curves observed in Leydig cell tumours comparing to germ cell tumours. With improved diagnostic confidence, testicular-sparing excisions were performed for 5 lesions following pre-operative CEUS analysis and unnecessary orchidectomies avoided. We describe, to date the first, consistent differentiating characteristic CEUS enhancement pattern in rare benign Leydig cell tumours. This observation increases diagnostic confidence, thus allows for testicular-preserving options to be considered. Purpose: To describe US and colour-Doppler findings in testicular lymphoma and their mimics. We reviewed the US and colour-Doppler findings in 10 pts with pathology-proven lymphoma of the testis and compared them with those in 7 patients in whom lymphoproliferative disease was suspected on clinical and US grounds and pathology showed only inflammatory changes. Results: Lymphoma patients' age range was 34-76 years. Six had testicular involvement in systemic disease or recurrence; four had primary disease. One had bilateral involvement. Seven testes in 6 patients were diffusely involved (4 homogeneously; 3 heterogeneously); four had nodular hypoechoic lesions which, in 1 testis, were multiple. All lesions, either focal or diffuse, were hypervascular, with vessels of normal rectilinear shape. In patients with nodular lesions, there was no distorsion of vascular course at the point where vessels entered the mass. Findings suggested an infiltrative process, and were confirmed at pathology. The remaining seven patients had history and US features suggesting testicular lymphoproliferative disease. All had hypoechoic focal hypervascular lesions containing vessels with rectilinear course that were eventually proved inflammatory changes (2 chronic focal orchitis, 2 idiopathic granulomatous orchitis, 2 brucellosis, 1 tuberculosis). Conclusion: In patients over 60 and/or with known lymphoproliferative disease, the presence of hypoechoic, hypervascular testicular lesion with absence of vascular distorsion must suggest lymphoma. Care must be taken since, albeit rarely, inflammatory lesions may present the same imaging pattern in the absence of clinical signs and symptoms of inflammation. Purpose: To assess the influence of region of interest (ROI) size and positioning on parameters of perfusion and permeability and inter-and intraobserver variability of DCE-MRI of renal cell carcinoma (RCC) and metastases. Methods and Materials: 33 patients with RCC and 17 patients with metastases were examined with dynamic contrast-enhanced (DCE) MRI at 1.5 T with a half body weight-adapted dose of gadobutrol. Analysis with a two-compartment exchange model provided four parameters: plasma flow (Fp), plasma volume (Vp), permeability-surface-product (Ps) and interstitial volume (VEE). Arterial input function and retrospective respiratory triggering were applied. ROIs of the whole tumour, circular edge and an arbitrary vital region were defined on morphological sequences and on parametric plasma flow maps. consider tube current modulation (TCM). The aim of this study was to include TCM effects in MC dose simulations and to validate this approach. Methods and Materials: All measurements were performed on a SOMATOM Definition Flash scanner (Siemens Healthcare, Forchheim, Germany) using three anthropomorphic phantoms: adult Alderson-Rando, 5-year-old child and 1-yearold child. The phantoms were scanned with a trunk protocol using an online TCM system (CareDose4, Siemens Healthcare, Forchheim, Germany). Organ dose values were measured using 94 calibrated thermoluminescent dosimeters (TLD) for each phantom. MC simulations were performed using ImpactMC software (CT Imaging GmbH, Erlangen, Germany) based on the 3D voxelised data derived from acquired CT images. The tool was modified to take TCM curves into account. The current values for different tube positions were extracted from the raw data using manufacturer software. Simulated dose values were compared with TLD measurements on a chip-by-chip basis. Results: For MC calculations without taking TCM data into account the mean differences between measured and simulated dose values amounted to 92%, 83%, 71% for adult, 5-year-old child and 1-year-old phantoms, while modelling with TCM reduced the mean differences to 5.3%, 7.5% and 6.4%, respectively. Conclusion: MC dose estimates including TCM data were in good agreement with measurements. This technique can significantly improve the accuracy of 3D-dose assessment. Monday 23 keV; pixel size 5.4µm), or at a laboratory set-up with a conventional x-ray tube (n=3, 35 kVp, 70 mA, pixel size 100µm). Tomographic images were reconstructed and compared to histopathology. Independent readers determined vessel dimensions and signal-to-noise ratios (SNR) between gb-PCI and absorption images. Results: In total, 51 sections were included in the analysis. Images from both setups provided sufficient contrast to differentiate vessel layers. There was a strong positive correlation between PCI and histology with respect for lumen, intima and vessel wall area for both synchrotron and laboratory-based measurements (Pearson's R > 0.94 and p < 0.01 for all). Synchrotron-based images were characterised by significantly higher SNRs than laboratory-based images (p < 0.001). Both gb-PCI set-ups had superior SNRs compared to corresponding absorption-based images (p < 0.001). Inter-reader reproducibility was excellent, with ICCs > 0.98 for synchrotron and > 0.84 for laboratory-based measurements. Conclusion: Our results demonstrate the feasibility of gb-PCI for carotid atherosclerotic plaque imaging using both synchrotron and laboratory-based experimental set-ups. The technique holds promise for accurate vessel wall characterisation. Single contrast medium dose peripheral MR angiography is feasible without subtraction using two-point Dixon fat saturation Purpose: To investigate the feasibility and image quality of subtractionless firstpass single contrast medium dose (0.1 mmol/kg) peripheral contrast-enhanced magnetic resonance angiography (MRA) using two-point Dixon fat-saturation (2DixFS) compared with conventional subtraction-based MRA with regard to vesselto-background contrast, signal-to-noise ratio (SNR) and subjective image quality. Methods and Materials: 28 patients (13M, 15 F; mean age±SD, 66±16) with known or suspected peripheral arterial disease underwent single contrast medium dose (0.1 mmol/kg body weight) 1.5-T MRA using 2DixFS during first arterial passage of contrast material. Results were compared with data obtained using a conventional, subtraction-based approach. A phantom study was performed to assess signal-to-noise ratio (SNR) of both MRA techniques. Vessel-to-background (VTB) contrast and SNR were measured and compared with the paired samples t-test. Two experienced observers scored subjective image quality. Fisher's exact test was used to compare subjective image quality. Agreement regarding subjective image quality was expressed in quadratic weighted κ values. Results: Patient data showed improved VTB contrast in all anatomical locations with 2DixFS versus the conventional, subtraction-based MRA method (all P < 0.001). Subjective image quality was uniformly higher with 2DixFS when compared with subtracted images. In all cases this was significant (P < 0.03), except the aortoiliac arteries for observer 1 (P=0.052). Phantom studies indicated a 15% higher SNR with the Dixon technique (31.9 vs 27.6). Conclusion: This study demonstrates the feasibility of single contrast medium dose subtractionless lower extremity MRA using 2DixFS method. Both objective and subjective image quality are better compared with subtraction based MRA of the peripheral vascular tree. Correlation of cardiovascular risk factors and occult atherosclerotic findings using whole body magnetic resonance imaging of the vascular system in an asymptomatic patient collective: initial results S. Mangold, E. Randrianarisoa, P. Krumm, C. Bretschneider, A. Seeger, K. Rittig, B. Balletshofer, C.D. Claussen, U. Kramer; Tübingen/ DE (Stefanie.Mangold@med.uni-tuebingen.de) Purpose: To evaluate the prevalence of atherosclerotic disease, myocardial infarction and cerebrovascular disease in asymptomatic patients with cardiovascular risk profile including whole body magnetic resonance imaging (WB-MRI) of the cardiovascular system into the framework of a comprehensive prevention concept. Methods and Materials: Prospectively, 52 patients without any known cardiovascular disease (34 men, 18 woman, mean age 50.1±7.4 years) but suffering from cardiovascular risk factors such as arterial hypertension [AHT], impaired glucose tolerance, hyperlipidaemia and obesity, were clinically assessed including family history, blood collection, blood pressure assessment and oral glucose tolerance test. Furthermore, the carotid intima-media thickness [CIMT], potentially indicative for atherosclerotic disease was assessed by ultrasound and a WB-MR angiography (1.5 T, Avanto, Siemens Medical Solutions) containing an examination of the of renal artery using respiratory triggered (RT) or breath held (BH) in reference to dynamic contrast MRA (CMRA). Methods and Materials: 33 patients were involved (median age 61 years). RT and BH NC MRAs using PG were obtained at 3 T (Discovery MR750, GEHC) using Inflow inversion recovery (IFIR) 3D FIESTA with fan beam k-space view ordering in a coronal plane. CMRA with 3D EFGRE was obtained as reference [0.1 mmol/kg Gd-chelate, injection 3 ml/sec]. Evaluation, image quality, artefacts (1 undiagnostic-5 excellent) and visualisation of aorta and renal arteries were ranked with 5-point scale. Contrast was calculated (SI artery/surrounding tissue). Wilcoxon signed rank test and Student's t test with Bonferroni correction was used for statistical evaluation. Results: ALL NCMRAs were diagnostic (3.7-4.7). Scores for image quality and artefacts of RT NCMRA were better than those of BH NCMRA (NS) although visualisation of aorta was slightly better with BH than RT NCMRA. RT NCMRA provided better visualisation of distal renal arteries and better contrast than those with CMRA (p < 0.05). Contrasts of aorta and proximal renal arteries were slightly better in CMRA than those in NCMRAs (NS). Conclusion: With PG, homogenous SI in aorta was obtained in NCMRA. When image quality of RT NCMRA is not enough to evaluate arteries, BH NCMRA can be used as substitute. Purpose: To evaluate the quality, the diagnostic performance and the radiation exposure of low-kV CT angiography protocol (100 kV) with ultra low-contrast medium volume (40 mL) in the assessment of the aorta disease. Methods and Materials: Seventy patients with thoracic or abdominal aortic disease were prospectively examined with 256MDCT scan (Brilliance iCT, Philips) using ultra low-dose radiation protocol (100 kV; automated tube current modulation) and ultra low-contrast volume (40 mL; 4 mL/s; 350 mgI/mL). In the thoracic aorta assessment we performed ECG-gated retrospective protocol, necessary for the evaluation of ascending aorta. Density measurements were performed on ascending, arch, descending, abdominal aorta, renal arteries and common iliac arteries. A control groups of 50 patients who underwent standard CT-angiography protocol (120 kV; 350 mAs) and standard contrast volume (120 mL) were also evaluated. The obtained data in terms of radiation dose exposure (dose-length product, DLP), administered contrast and intravessels density were compared and statistically analysed. Results: In every CT-exam we could correctly visualise and evaluate main branch of thoracic and abdominal aorta. No significant difference of density measurements was achieved between the low-kV protocol: mean attenuation value of thoracic aorta 304 HU, abdominal aorta 343 HU and renal arteries 331 HU; and control group: mean value of thoracic aorta 320 HU, abdominal aorta 339 HU and renal arteries 303 HU. The radiation dose exposure in low-kV protocol was significantly reduced (p < 0.05) in comparison with control group, obtaining the following value for thoracic scan: 490DLP and abdominal scan: 335DLP, while in control group we obtained for the thoracic scan: DLP625 and for the abdominal scan: DLP952, respectively. Conclusion: Low-kV protocol provides a comparable diagnostic performance with standard protocol, decreasing significantly the radiation dose exposure (over 40%) and allowing also a significant reduction of contrast material volume (40 mL), preserving renal function. X-ray phase-contrast imaging of arterial vessel wall: translation from synchrotron radiation to a conventional lab-based x-ray source H. Hetterich 1 , M. Willner 2 , S. Fill 1 , F. Bamberg 1 , J. Herzen 2 , M. Stockmar 2 , F. Pfeiffer 2 , M.F. Reiser 1 , T. Saam 1 ; 1 Munich/DE, 2 Garching/ DE (holger.hetterich@med.uni-muenchen.de) Purpose: Phase-contrast imaging (PCI) is a novel x-ray-based technique that provides excellent soft tissue contrast but so far was depending on synchrotron radiation. The aim of this study was to evaluate the feasibility of visualising human carotid arteries by grating-based PCI (gb-PCI) at two different experimental setups: (1) applying synchrotron radiation and (2) using a conventional x-ray tube. Methods and Materials: Five ex-vivo carotid artery specimens were examined with gb-PCI either at a synchrotron facility using a monochromatic x-ray beam (N=2; developed for adult trauma patients in 2008 and a novel approach based on recent literature and our additional observations. Results: Of the 14 years considered, 136 cases met the inclusion criteria. In 33 cases a NAHI was assumed. 17 cases showed SDHy. Only one SDHy case was assumed to be related to an accident. The new classification system for traumatic SDHy in children will be introduced and discussed. Conclusion: As demonstrated for different SDHy appearances, neuroradiologists should be aware of the possible presentations of NAHI. In addition, investigation of SDHy's may allow for new insights into the pathogenesis of phenomena such as the shaken baby syndrome. Apparent kurtosis coefficient (AKC) in brain: a feasibility study in paediatric populations I. D'Errico, A. Ciccarone, M. Esposito, M. Mortilla, C. Fonda; Florence/IT (igni77@hotmail.it) Purpose: Diffusion-weighted imaging (DWI) depends on the b-values employed in acquisition. At low b values (lower than 500 s/mm2) the signal attenuation is bi-exponential and is influenced both by diffusion and perfusion. At high b values (higher than 1000 s/mm2) the signal attenuation is influenced by restricted water diffusion and hence follows a non-Gaussian distribution. Diffusion Kurtosis Imaging (DKI) provides quantifiable information about the deviation from Gaussian distribution in water diffusion process. Our purpose was to apply DKI method to paediatric patients with different pathologies (tumours, ischaemia) and to establish its feasibility in detecting brain diseases. We examined 20 patients from newborn to 16-year-old. Diffusion weighted imaging was performed with 5 b values from 500 to 2500 with step 500 s/mm2. Fitting all b values we were able to discriminate Diffusion and Kurtosis parameters. A home-made software performed all fitting and DWI, ADC, AKC maps. Results: AKC maps revealed additional information for tissue characterisation. In ischaemia, AKC demonstrated more details of pathologic tissue changes and provided information about prognosis. In tumours, AKC maps were used for discriminating low-grade from high-grade lesions revealing a better accuracy than conventional diffusion parameters. Conclusion: AKC maps are non-invasive methods that are well tolerated by paediatric patients and that provide a more detailed characterisation of neural tissue in the clinical context. Their application in pathological conditions such as ischaemia and tumours provides additional information about microstructural tissue changes, differential diagnosis and prognosis. Which T1 pulse should be used to study the preterm brain with a 3 Tesla scanner? D. Tortora, V. Panara, P.A. Mattei, S. Salice, M. Tagliamonte, C. Briganti, A.R. Cotroneo, A. Tartaro, M. Caulo; Chieti/IT (domenicotortora@hotmail.it) Purpose: The loss of contrast on MR T1-weighted images obtained at 3 Tesla (3 T) may negatively influence the detection of punctate hyperintense lesions, which are indicative of periventricular leukomalacia (PVL) in preterm neonates. In this 3 T MR study we compared the sensitivity of different T1-weighted sequences in identifying PVL. The presence of non cystic-PVL was retrospectively evaluated in 3 Tesla (3 T) MR brain studies of 200 preterm neonates acquired at term-corrected age. In 30 neonates with PVL, T1 hyperintense punctate lesions were counted by two neuroradiologists in consensus on 4 different axial T1-weighted sequences: 3 mm Inversion Recovery (IR), Spin Echo (SE), reformatted 3D-Fast Field Echo (FFE) and 1 mm reformatted 3D-FFE. Sequences were presented randomly. Statistical differences of the number of hyperintense lesions detected by the different sequences were evaluated using the Student's paired t test (p < 0.05). Results: The greater number of T1 hyperintense punctate lesion was identified using the 1 mm axial reformatted 3D-FFE sequence (381 lesions), which resulted to be the most sensitive sequence in identifying PVL lesions (p < 0.0001). Axial 3 mm FFE, IR and SE sequences identified 213, 146 and 94 hyperintense punctate lesions, respectively. No statistical differences were found between 3 mm-T1 sequences (p> 0.05). Conclusion: When using a 3 Tesla MR scanner 1 mm axial reformatted T1-3D-FFE is the most sensitive T1-weighted sequence for detecting punctate hyperintense lesions which may affect the brain of preterm neonates. brain and the heart was performed. A vessel score, determined from the sum of arteriosclerotic changes of all evaluated vessel divided by the number of vessels with a range from 1, normal to 6, stenosis > 99%, was introduced and score's association with risk factors was assessed. Results: The mean MRI score was 1.51±0.18.The WB-MR angiography-based score was significantly associated with the body mass index [BMI] (p=0.024) and AHT in combination with an elevated BMI (p=0.042). No significant associations were found for age (p=0.706), sex (p=0.502), impaired fasting glucose (p=0.277), hyperlipidaemia (p=0.218) and CIMT (p=0.183) . No patients with myocardial infarction and 2 patients with cerebrovascular disease were found. Conclusion: WB-MR angiography allows the detection of occult atherosclerotic disease in asymptomatic patients with cardiovascular risk profile especially in cases of AHT and/or obesity. 14:00 Purpose: To evaluate image quality and radiation dose of ultra-low-dose CT examinations of the inner ear performed using adaptive statistical image reconstruction (ASiR) in infants candidate to cochlear prosthesis implantation. We evaluated 24 infants (14 males, 10 females, age 4-29 months, mean 17 months) with sensorineural deafness who underwent CT of the inner ear before cochlear prosthesis implantation. Out of them, 13 were imaged on a 128-row CT scanner (Discovery CT750 HD, General Electric, Milwaukee, WI) using an ultra-low dose protocol (80 kV, 10 mA, 0.5s gantry rotation time) and a model-based iterative reconstruction algorithm (ASiR™), while in the remaining 11 CT had been performed on a 64-row scanner before the introduction of the 128-row CT equipment at our Institution, using a regular paediatric protocol (100 kV, 30 mA, 0.5s gantry rotation time) with conventional filtered backprojection. Dose-length product (DLP) values were obtained from dose reports generated from the scanner at the end of each examination. Image quality was rated in blind by two radiologists using a Likert scale (1=non-diagnostic through 5=excellent). Results: None of the examinations were rated as non-diagnostic. Image quality was comparable between the 128-and the 64-row CT group (4.45±0.63 vs 4.51±0.56, respectively; p=0.31). DLP was significantly lower in the 128-row CT group (5.46±0.35 vs 25.69±0.83 mGy*cm, respectively; p < 0.001). Conclusion: Compared with a regular paediatric protocol, ultra-low-dose CT of the inner ear with ASiR allows for markedly reduced radiation dose with preserved image quality. Traumatic subdural hygromas in children between 0 and 2 years: a retrospective CT and MRI study M.L. Hahnemann 1 , A. Schmeling 2 , M. Schlamann 1 , M. Forsting 1 , H. Pfeiffer 2 , D. Wittschieber 2 ; 1 Essen/DE, 2 Münster/DE Purpose: Non-accidental head injuries (NAHI) represent a leading cause of death in infants. In this context, the role of traumatic subdural hygromas (SDHy) as possible acute or chronic finding in child abuse, especially in shaken-baby-syndrome, is not well understood and still a matter of debate. By modern imaging techniques, the present study aimed to investigate the characteristics of SDHy. Methods and Materials: From the years 1999-2012, we retrospectively analysed the images of all children between 0 and 2 years who were suspected to have a craniocerebral injury and got an initial cranial computer tomography at the University Hospital Essen. In cases where additional MR examinations existed these MR images were also analysed. All skeletal and cerebral pathologies, demographic data, and, if existing, related clinical anamneses and findings were recorded. All SDHy cases were classified according to both a classification system originally S38 C A D E F G B is a major cause too (N=26). Spearman rho correlations between radiographer's time of experience and frequency of MRI exams repetitions were poor and not significant (r=0.141; p=0.297). The correlations between radiographer's tiredness and frequency of MRI exams repetitions were negative, weak and not significant (r= -0.151; p=0.263). The patients' movement may disrupt the examination or degrade the images with artefacts. The level of experience does not influence the repetitions of MRI exams, it seems that senior radiographers do not have improvements in performance as it should be expected. It is recommendable to do training courses regularly to improve the performance and systematically evaluate. Several features will need to be identified which would decrease the MRI exams repetitions. Functional mapping of the visual word form area with frequent words of the Portuguese lexicon: an fMRI study C. Ferreira 1 , P. Martins 2 , G. Cunha 1 , N. Canário 1 , C. Nunes 1 , A.C. Miranda 2 , J. Ribeiro 2 , S. Afonso 2 , M. Castelo-Branco 1 ; 1 Coimbra/PT, 2 Aveiro/PT (c_dferreira@yahoo.com) Purpose: The visual word form area (VWFA), part of the fusiform gyrus in the temporal lobe underlies word form encoding. Impairment of this region causes reading deficits, including alexia. The aim of this study is to functionally map VWFA at the individual subject level using frequent words of the Portuguese lexicon, to develop a paradigm potentially useful for clinical patients. Methods and Materials: Functional magnetic resonance images (fMRI) were acquired in from nine subjects. The visual paradigm used consisted of 13 blocks (30 seconds block duration): 7 baseline (checkerboard stimuli), 3 blocks of frequent words and 3 of pseudo-words (40 words/pseudowords per block). General linear model analysis was performed using BrainVoyager Qx to identify brain regions encoding word form. Results: An area corresponding to VWFA could be mapped in both hemispheres in all subjects at a statistical threshold of 0.001, corrected for multiple comparisons. Seven of the cases had predominant activation in the left hemisphere, one has equivalent activations bilaterally and one subject has predominant activation in the right hemisphere. The number of activated clusters was significantly larger in the left hemisphere at the group level (p = 0.015, Wilcoxon signed rank test). Conclusion: Bilateral activation was replicated in VWFA in all subjects, with a clear left hemispheric dominance demonstrating the robustness of the paradigm, making it potentially useful in a clinical setting, e.g. pre-surgical mapping. A survey of the various methods and techniques employed in myocardial stress testing K. Borg Grima 1 , L. Rainford 2 , P. Bezzina 1 , D. O'Leary 2 ; 1 Msida/MT, 2 Dublin/IE (karen.borg-grima@um.edu.mt) Purpose: Literature suggests a range of pharmacological stress agents and radioactive tracers, together with a variety of defined protocols that may be used in conducting myocardial stress testing prior to cardiac scintigraphy imaging. An online survey was performed to evaluate current practice. Methods and Materials: A survey was developed comprising of twelve questions, by using 'Survey Monkey', which aimed to identify the variances present in conducting myocardial stress testing and in clinical protocol details if available. Professional groups working in Nuclear Medicine, such as the medical-physicsengineering community and virtual radiopharmacy, were targeted. Access to the survey remained open for eight months. Forty-three members, including both radiographers and medical physicists responded from across Europe and Australasia. SPSS was used to evaluate the results obtained, based on Chi-square tests and comparisons between multiple responses. Results: The majority (72%) of the participants were from United Kingdom, 18% from other European countries and 9% from Australasia. In 39 centres pharmacological stress testing was performed either alone or in conjunction with exercise stress testing. The results indicated that 60% of the participants were aware of local stress test protocols; however, guidelines indicating which patients were not suitable for pharmacological stress tests may require clarification. Conclusion: Results suggest that for pharmacological stress testing there is a need for increased awareness of protocols, and across all responders the need for improved knowledge and understanding of local protocols was identified. This initial survey justifies further research towards increase protocol compliance and standardisation of practice during myocardial stress testing. Templates were built taking into account the age of patients. Artefact movements and eddy current distortions were removed. Mean diffusivity (MD) and fractional anisotropy (FA) were quantified together to the three principal directions of diffusion (eigenvectors) with their own eigenvalues (tensor diagonalization). So analysis of single fibre orientation for each voxel with a bayesian algorithm was executed. Voxelwise statistical analysis of the FA, MD and axial diffusivity data was carried out using TBSS between focal cortical abnormalities sites and normal ones. Results: Different pattern of cortical organization and white matter projections are evidenced depending of lesional load and extension, site and age. In focal cortical abnormalities the TBSS analysis revealed significant differences (p < 0.05) between affected cortical sites and normal ones. Conclusion: Different FA data were collected. The reductions of FA, the associated elevation of diffusivity in altered contiguous or distal area are evidenced. 14:00 Purpose: The magnetic resonance imaging (MRI) uses the magnetic field effects to its functioning. This study aimed to clarify the EMF Directive 2004/40/EC discussion which imposes limits to electromagnetic fields (EMF) regarding the occupational exposure. Methods and Materials: It was explored policy documents, regulations, guidelines, laws and other official documents on this subject. To understand the reason of this controversy, the evidence of consequences from the EMF exposure over professionals was analysed. From the information obtained an online survey was developed, with national and international coverage, towards 11 professional groups considered involved in the controversy. The opinions were analysed by the force field analysis diagram, through the Policymaker K4-health™ application to speculate the influences, forces, power and strategies developed in this process. Results and Conclusion: From 50 respondents 62% do not know the ESR's position, the Directive and its contents. 60% know the safety measures to apply in the MR room and report adverse events for lack of compliance with safety standards, being the levels of SAR, the most topic referred. They do not know the limits imposed and have no opinion about the Directive's controversy (40%). The political impact is considered neutral (49%) against the negative clinical and economic impacts (54%) that falls over the equipment manufacturers (62%). The professional societies have most decision, followed by physicists, doctors, manufacturers, government decision-makers and health-managers. The manufacturers, radiographers and supervisors have median influence, and the patients have weak influence over this process. On this matter influences and pressure strategies over the European Commission and Council were recognised. Radiographers perceptions of magnetic resonance imaging: a study of the causes that lead to the repetition of exams T.R. Filipe 1 , L.P.V. Ribeiro 1 , R.P.P. Almeida 1 , S.I. Rodrigues 1 , K.B. Azevedo 1 , C.A. Silva 2 , A.F.L. Abrantes 1 ; 1 Faro/PT, 2 Évora/PT (tiagofilipe__@hotmail.com) Purpose: To know how often repetitions of MRI exams and sequences occur in radiology departments. A self-applied questionnaire was used as instrument and assigned to 57 radiographers who performed MRI exams to determine which were the causes that lead to the repetition. The questionnaires were interpreted and statistically analysed through descriptive statistics and Spearman's rho correlation. Results: At a 95% confidence interval, the major results suggest that the patient's movement during the MRI exams is the main cause to repeat this exams (mean of 3.88 on a 5-point Likert scale). However, there are causes related to the radiographer's and the results showed that the introduction of wrong imaging parameters S38 A C D E F G Results: The percentage of depression among MRI technologists included in our sample was found to be 25% which is considered to be much more than the percentage (10%) found among the dentists in USA (6.5%) and among community population in Saudi Arabia. Conclusion: It was found that there is a strong relationship between the incident of depression among MRI technologists and the incident is higher among technologists working for more than 5 years. Development and implementation of a synthetic data evaluation scenario for image fusion algorithms based on discrete wavelet transform and principal component analysis V. Weiss; Wiener Neustadt/ AT (volker.weiss@hotmail.com) Purpose: Successful image fusion reduces the amount of data without significantly reducing the amount of relevant information. This study aims to answer the question whether the image fusion results were calculated successfully and what successful image fusion actually means. The study presents two new approaches for the quantitative evaluation of image fusion schemes. It provides the development and implementation of a synthetic data evaluation scenario for image fusion algorithms based on discrete wavelet transform (DWT) and principal component analysis (PCA). Furthermore, it presents a medical application visualising and comparing fused axial CT slices, reconstructed from a CT volume data set with identical position but calculated with different convolution kernels. The study provides a ground truth data-based performance evaluation, as well as a comparison of the DWT and PCA to each other by computing and visualising significant differences in their performance. Results: In the present study, the DWT, compared to the PCA, turns out to be the more powerful and therefore more suitable image fusion method, both qualitatively and quantitatively. Conclusion: According to estimates of certain surveyed medical specialists, to whom the results have been shown, a serious diagnosis solely on the basis of fused images is conceivable. The fused images would also be conceivable for documentation purposes and printouts for the referring physicians. Finally, storing fused image series instead of individual series would reduce the amount of memory required in long-term archives by half. Image registration and fusion of CT and micro-CT of a sheep's cochlea S. Leitner; Berndorf/AT Purpose: The sheep's cochlea seems to be most similar to human ones. Hence, it is of great interest in the fields of developing cochlea implants and improving operation techniques of electrode implantation in ENT-(ear-nose-throat) surgery. Methods and Materials: For investigating the sheep as a suitable large animal model, data sets of high resolution micro-CT and CT of its cochlea were acquired. The research on inner-ear diseases and ENT-surgery methods require image processing methods, such as image registration and image fusion. In this thesis, the micro-CT data set was registered with the CT data set in a common coordinate system using two different software packages. The registration was successful with both types of software. In order to evaluate the results visually, the fused multimodal data were represented by means of colour overlay as well as 3D rendering techniques. The basis of image-registration of these two modalities was laid and serves as comparison between the image information of the high resolution micro-CT and the conventional CT in order to overcome an interpretation gap between these two modalities. The appropriate 3D visualisation of the vestibule-cochlea system by means of the highest resolution image devices and medical image processing methods support fundamental research on macro-and micro-mechanical processes of hearing and basic understanding for developing therapeutic and preventive methods for ear diseases. Purpose: Scout images are essential in neuroradiology. Though these images may have limited diagnostic quality, they visualise larger parts of the body. Therefore, certain radiologic findings may be visualised only or largely in the scout images and truly constitute unexpected radiologic findings (UF). Impact related to spinal location and imaging modality on to the incidence and distribution of UF remains unknown. Methods and Materials: 500 patients undergoing CT and 500 patients undergoing MRI of spinal column between 11/01/2009 and 1/31/2010 are included. UF reported in the original dictations are separated into 3 groups: scout only (I), scout+diagnostic images (II) and diagnostic images (III) only. In addition to type of imaging and spinal location, locations and organ system of these findings are recorded. Results: There were 81 UF in CT and 113 in MRI group. In both groups, patients with UF were significantly older than the ones without UF, with a slight female preponderance. Majority of UF in CT were seen in diagnostic images. UF seen only in scout images of CT were exception although these were significant findings. UF distribution in MRI was more even. Equal numbers of UF were seen in groups II and III. Approximately 17% of UF seen in MRI were present in group I. Conclusion: Scout images of neuroradiologic studies may harbour significant number UF. This is especially true in MRI where 17% of UF seen only in scout images. Although UF seen solely in scout images of CT is rare, these are predominantly significant findings. Comparison of a 12-channel-with a 32-channel head coil using SNR measurements C. Vandulek, D. Kaczur, E. Vinczen, I. Repa; Kaposvár/HU (cvandulek@gmail.com) Purpose: One of the key attributes characterising the quality of an MRI head coil is the signal-to-noise ratio (SNR). The purpose of this study was to compare a 12-channel-with 32-channel head coil using standardised SNR measurements. The measurements were performed on a 1.5 T MRI scanner. The SNR measurements were performed on the coils' phantoms and on volunteers. The SNR protocol consisted of axial T1 FSE and T2 FSE measurements. Analysis of the SNR calculations was performed using ROI's positioned in the phantoms and the brain tissue of the volunteers. The results of the SNR measurements of the phantoms show that the SNR of the 32-channel coil is double that of the 12-channel head coil. However, the SNR of the volunteers showed only a 65% increase of SNR with the T1 FSE measurement, and a 30% increase with the T2 FSE on the 32-channel coil. There were no artefacts observed on either measurements of the phantoms and human volunteers. Conclusion: This study confirmed a difference of the SNR between the 12-and 32-channel head coil. While the phantom measurements showed a twofold increase of SNR between the two coils, this rate was not confirmed on the human volunteers. The results of this study amplify the advantage of using the 32-channel coil for neuroradiological examinations (e.g. fMRI, MRS), whereas the 12-channel coil is sufficient for routine brain examinations. Psychological effect of chronic exposure to high magnetic field on MRI technologists N.M. Mishah, W. Hamed; Jeddah/SA (nabeel747@hotmail.com) Purpose: The purpose of this study is to measure the incident of depression among MRI technologists since they are chronically exposed to high magnetic fields that may carry occupational hazard on central nervous system and on their brain chemicals. This may cause a long-term psychological side effects such as depression. The data and the statistical information of this project were based on BECK Depression Inventory BDI, 1996 version which is used by healthcare professionals as depression screening tool. The questionnaire of depression screening tool was delivered to all MRI technologists working in major hospitals within large cities in Makkah region. The total completed questionnaire received was 45 and only 40 was accepted with a rejection rate of 11.11%. The received data were analysed using a computer-aided statistical tool then the percentage of depression found among MRI technologists included in our study will be compared to previous study conducted on dentists in USA and among community population in Saudi Arabia. S38 C A D E F G B Conclusion: Regorafenib significantly suppressed tumour perfusion and vascularity quantified by DCE-CT in experimental colon carcinomas in rats with good to moderate correlations to an immunohistochemical gold standard. Tumour response biomarkers assessed by DCE-CT might be a promising future approach to a more personalised and targeted cancer therapy. Author Disclosures: K. Nikolaou: Research/Grant Support; Bayer Healthcare, Germany. C.C. Cyran: Research/Grant Support; Bayer Healthcare, Germany. Contrast-induced nephropathy in patients undergoing intravenous contrast-enhanced computed tomography and the relationship with risk factors: a meta-analysis S.I. Moos, J. Stoker, S. Bipat; Amsterdam/NL (s.i.moos@amc.uva.nl) Purpose: To summarise the incidence of contrast-induced nephropathy (CIN) and to study associations between CIN and risk factors in patients undergoing intravenous contrast-enhanced computed tomography (CECT). We searched the MEDLINE, EMBASE and Cochrane databases from 2002 till July 2012. Two reviewers checked inclusion criteria and extracted data. Mean CIN incidence and associations between risk factors and CIN were pooled by random-effect approach. Results: Twenty-three articles with 20,000 patients (mean age 64.5 years, mean eGFR at baseline 55.17 mL/min) were included. CIN was defined as absolute or relative (44.2 µmol/L/> 25%) serum creatinine increase, mostly within 72 hours. All studies included a high proportion of patients with risk factors; chronic kidney disease (CKD) in 52% of all patients, diabetes mellitus (DM) in 14%, hypertension (HT) in 54% and congestive heart failure (CHF) in 21%. The mean incidence of CIN was 3.7% (95% CI: 2.5%-5.6%). Data analysis showed an increased risk for CIN in the presence of DM ((odds ratio 1.73 (95% CI: 1.07-2.82), p=0.03)) and CKD (2.52 (95% CI: 1.56-4.08), p=0.0002). HT and CHF were not associated with an increased risk (p=0.07, p=0.19). The mean incidence of CIN after CECT was 3.7% and is associated with DM and CKD. The incidence of CIN is mostly reported in studies with a high proportion of patients with risk factors. Therefore, the reported CIN incidence and associated risk factors for CECT might be overestimated compared to the CIN incidence in a general population undergoing CECT. Purpose: To determine whether contrast agent (CA) dose reduction to one-half and one-quarter of the standardised dosage allows for preserved image quality of renal MR angiography at 7T. Methods and Materials: MR examinations were performed in 6 healthy subjects on a 7T MR system (Magnetom 7T), utilising a custom-built 8-channel RF body coil. Dynamic 3D FLASH data sets were obtained pre contrast and 20sec after the application of contrast agent. Examinations were performed at three different time points for injection of three dosages of CA (Gadobutrol, Bayer Healthcare): (1) 0.1 mmol/kg body weight (BW), (2) 0.05 mmol/kg BW and (3) 0.025 mmol/kg BW. Contrast ratios (CR) were measured pre and post contrast in the aorta and both renal arteries in correlation to adjacent psoas major muscle. Qualitative analysis with regard to delineation of the pre-contrast and post-contrast renal arterial vasculature was performed by two radiologists using a five-point-scale (5=excellent to 1= non diagnostic). Results: Non-enhanced T1w MRI provided an inherently high signal intensity of vasculature, yielding a good overall pre-contrast arterial delineation (mean 3.65). The application of contrast agent showed improved vessel delineation in qualitative and quantitative analysis for all three dosages, yielding comparable results in subjective ratings of qualitative analysis (mean0.025Gd 4.55; mean0.05Gd 4.50; mean0.1Gd mean 4.60). Quantitative analysis of contrast ratios showed only minor increase of mean values with increasing Gadolinium dosage (mean0.025Gd 0.08; mean0.05Gd 0.15; mean0.1Gd mean 0.18). Conclusion: 7T CE-MRA allows for a significant dose reduction to one-quarter while maintaining high image quality. Diagnostic accuracy of dynamic gadoxetic-acid-enhanced MRI and PET-CT in patients with liver metastases from neuroendocrine neoplasms Purpose: To evaluate the diagnostic accuracy of dynamic gadoxetic-acid-enhanced MRI parameters in comparison to standardised uptake values (SUV) from both patients with proven liver metastases of neuroendocrine neoplasms (NEN) Up to three regions of interest (ROIs) were defined in metastases (> 2 cm) and liver tissue in morphological images. Corresponding ROIs were defined in the DCE-MRI dataset and in the PET-CT dataset. Diagnostic accuracy for all perfusion parameters were evaluated for the differentiation between metastases and liver tissue: arterial and venous plasma flow (APF and VPF), extracellular mean transit time (exMTT), extracellular volume (exVol), intracellular uptake rate (UR) of Gd-EOB-DTPA and arterial flow fraction (AFF) as well as SUVs derived either from 18 F-FDG or from 68 Ga-DOTATATE-PET-CT. Results: Area under the curve for different DCE-MRI parameters was between AUC=0.559 (extracellular mean transit time) and 0.901 (arterial plasma flow -sensitivity: 91.9%, specificity: 77.3%, cut-off value: 26.0 ml/min/100 ml). Sensitivity and specificity of SUVmean derived from 68 Ga-DOTATATE were 92.6% and 93.8%, respectively (AUC = 0.966). SUVmean derived from 18 F-FDG-PET-CT showed a sensitivity and specificity of 95.0% and 91 CP class liver damage groups. Chi square test was used for statistics and p < 0.05 was considered statistical significant. Results: In poor HBP cases (n=76), ER of HBP and SDP were 0.88±0.16 and 0.64±0.16. In control cases (n=20), ER of HBP and SDP were 0.54±0.08 and 0.39±0.06. ER of HBP and SDP in CP-A poor HBP (n=27), CP-B poor HBP (n=47), CP-C poor HBP Conclusion: In most of the poor HBP image cases, SDP image improve parenchymal and vascular contrast except CP-C liver damage cases Results: We found characteristic signal criteria in all analysed plaque components. Applying these criteria gb-PCI had a good sensitivity for the detection of FC/NC, IPH and Ca (all > 80%) and excellent specificity and accuracy (all > 90%) with good inter-reader agreement ([[Unable to Display Character: к]]³0.72, p < 0.0001). There were excellent correlations for quantitative measurements of FC, NC and Ca between gb-PCI and histopathology (R³0.92). Inter-reader reproducibility was excellent with ICC³0.98 for all measurements. Conclusion: Gb-PCI can identify and quantify atherosclerotic plaque components in a lab-based set-up with excellent correlation to histopathology. Imaging of the therapeutic efficiency of photodynamic therapy with a new designed fluorescence optical annexin probe K. Haedicke, S. Gräfe, F. Lehmann, W.A. Kaiser, I. Hilger; Jena/ DE (Katja.Haedicke@med.uni-jena.de) Purpose: Photodynamic therapy (PDT) destroys tumour tissue via generating reactive oxygen species after administration of a photosensitizer and illuminating the tumour with light. Next to many other molecular processes, apoptosis occurs in the tumour after this therapy. We designed a new fluorescence optical probe based on annexin V to detect this therapeutic effect after PDT in vivo via non-invasive near-infrared fluorescence optical imaging. Methods and Materials: Annexin V was labelled with the near-infrared dye DY-734-NHS and characterised spectroscopically. Binding affinity of the probe to apoptotic tongue-squamous epithelium carcinoma (CAL-27) cells was analysed by Purpose: To evaluate the potential of the reconstruction algorithm iDose to preserve image quality in brain-CT acquired with 30% reduced radiation dose and to evaluate image quality assessment methods. Interaction of magnetically labelled multipotent mesenchymal stromal cells and E-/P-selectins monitored by magnetic resonance imaging in mice J. Salamon, K. Peldschus, D. Wicklein, C. Lange, H. Ittrich, U. Schumacher, G. Adam; Hamburg/ DE (j.salamon@uke.de) Purpose: This study's purpose was to analyse the influence of E-and P-selectins on the migratory pattern of magnetically labelled multipotent mesenchymal stromal cells (MSC) in E-/P-selectin deficient (KO) and wildtype (WT) mice using MRI and fluorescence microscopy. Methods and Materials: Murine MSC were labelled with fluorescent iron-oxide micro-particles and carboxyfluorescein succinidylester. The ability to bind selectins and the expression of typical MSC markers were assessed by flow cytometry. Labelled MSC were injected into KO-and WT-mice applying doses of 5 × 104 cells intracardially, 1 × 106 cells intravenously and 5 × 106 cells intraperitoneally. Mice underwent sequential MRI at 3.0 T using high-resolution T2* 3D and 2D coherent gradient-echo sequences and histological evaluation after 7 days. Results: Expression of typical MSC markers and binding abilities to E-/P-selectins were found similar after labelling. After intravenous cell injection in KO-mice significant SNR decrease was assessed solely in the liver from day 0 to 1; WT-mice revealed an increasing SNR decrease of liver, spleen and bone marrow within 7 days. After intraperitoneal injection no significant SNR changes were observed in KO-mice; WT-mice showed an increasing SNR decrease of liver, spleen and bone marrow within 7 days. After intracardiac injection multiple susceptibility artefacts could be detected no longer then day 4 in KO mice but persisted up to day 7 in WT-mice. Fluorescence microscopy confirmed MRI findings. Conclusion: This study demonstrates that MSC retain their binding ability to E-/P-selectins after magnetic labelling. E-/P-selectin deficiency in mice significantly alters the distribution of magnetically labelled MSC. DE (holger.haubenreisser@medma.uni-heidelberg.de) Purpose: To prospectively compare the image quality of cranial computed tomography (cCT) with thin slice widths using traditional filtered back projection (FBP) and sinogram-affirmed iterative image reconstruction (SAFIRE). Methods and Materials: 40 consecutive studies (19 men; 71.6±16.6 years) referred for cCT were prospectively included. Each cranial CT raw data set was reconstructed with FBP and SAFIRE with decreasing slice widths (5 mm-1 mm). Objective image quality was assessed by measuring image noise in three predefined regions of the brain (white matter, thalamus, cerebellum) using identical regions of interest (ROIs). Subjective image quality was assessed by 2 experienced radiologists by ranking the reconstructed data sets with respect to overall image quality. The Mann-Whitney U-test and Cohen's Kappa were used for statistical analysis. Results: Image noise was statistically significantly reduced in all SAFIRE images at identical slice widths when compared to the images reconstructed with FBP (4.26±0.43 HU vs. 7.67±1.19 HU at 1 mm slice width) (p < 0.001). Mean signal attenuation for each region and slice width remained constant between the two reconstruction methods (p> 0.5). SNR was comparable between 1 mm SAFIRE images and 5 mm FBP images. Subjective image quality of SAFIRE images was rated consistently higher than that of the FBP images (p < 0.001). Interobserver agreement was excellent between both radiologists (Cohen's K = 0.79-0.86). Conclusion: Iterative image reconstruction significantly reduces image noise, while increasing image quality. In cCT this may be used to decrease slice width and thus reduce partial volume effects, which may lead to increased diagnostic accuracy. Purpose: The aim of our study is to demonstrate the effectiveness of 3D MRI in the diagnosis of lumbar radiculopathy in comparison with clinical and neurophysiological data. Methods and Materials: 32 patients with L5 or S1 monoradiculopathy caused by a posterolateral or intraforaminal disk herniation underwent MRI examination after preliminary clinical assessment and electromyography (EMG). We performed conventional spin-echo and 3D coronal FFE sequences with selective water excitation (ProSet imaging). Using 3D coronal FFE sequences indentation, swelling and tilting angle of the nerve root were evaluated. The tilting angle was compared with the asymptomatic contralateral side of the nerve root. All the data were processed using Epi Info 3.3 software (CDC, Atlanta, GA, USA) and were compared by means of Fisher exact test. Results: ProSet sequence revealed abnormal tilting angle in 18 patients (57.2 %; p < 0.05), monolateral swelling or indentation of roots and spinal nerves in 28 patients (85.7%; p < 0.001). In 10 patients EMG demonstrated an involvement of more than one nerve roots, whereas the ProSet revealed only one involved root. In 2 patients the nerve alterations were revealed only by EMG. Conclusion: EMG has an improved ability to highlight the early changes of the roots caused by mechanical and biochemical alterations due to compression. ProSet Imaging demonstrates high sensitivity in identifying the exact level of the involved root and can provide a useful tool to plan surgical treatments. Purpose: To investigate the utility of DTI in detecting nerve injury or neuropathic changes in proximal nerve segments in patients with peripheral neuropathy. Methods and Materials: Twenty-four age-matched individuals with (n=14) and without (n=10) peripheral neuropathy underwent DTI of a defined sciatic nerve segment. Patients and controls were evaluated by clinical examination and nerve conduction studies at baseline and six months after the initial DTI scan. Four patients were scheduled for a second scan six months after the initial MRI. Results: The mean FA value was significantly lower in sciatic nerves from patients with peripheral neuropathy as compared to controls. Sciatic nerve FA values positively correlated with clinical disability scores and electrophysiological parameters of axonal damage, i.e. the compound muscle action potential amplitudes of the peroneal and tibial nerve at baseline and six months after MRI scan. No correlation was found with axial and radial diffusivities. Conclusion: DTI-derived FA values are a sensitive measure to discriminate healthy from functionally impaired human sciatic nerve segments. This technique might be potentially useful in estimating the proximal axonal degeneration burden in patients with peripheral neuropathies. Purpose: The purpose is to describe the imaging features of the involved brainstem and spinal cord tracts in cases of leukodystrophy with brainstem and spinal cord involvement and brain lactate elevation (LBSL). The importance of craniovertebral and cervicomedullary angle on cervicogenic headache G. Çoban 1 , I. Çöven 1 , E.B. Çifçi 1 , E. Yıldırım 1 , C.A. Yazıcı 2 , B. Horasanlı 1 ; 1 Konya/TR, 2 Ankara/TR (drgokcencoban@gmail.com) Purpose: Many studies indicated that cervicogenic headache (CH) may originate from cervical structures innervated by the upper cervical spinal nerves and the trigeminal nerve branches. Studies to date have not investigated whether the narrowing of the craniovertebral angle (CVA) and cervicomedullary angle (CMA) affects the nerve branches and causes pain. The aim of this study was to investigate the effect of the narrowing of the CVA and CMA values on the occurrence CH. Methods and Materials: Between January 2011 and May 2012, 205 patients with the diagnosis of CH were included in the study. The pain scores in patients were carried out using a visual analogue scale from 1 to 4 (pain groups Purpose: To assess the image quality after image-based processing of low-dose single-rotation intra-procedural 4D-FD-CT (SR 4D-FD-CT). Multiple rotation contrast-enhanced 4D-FD-CT is associated with many C-arm projections (~1000 projections) and a high amount of contrast agent (CA). In this feasibility study, we used a single-rotation of the C-arm (Artis zee biplane, Siemens AG, Healthcare Sector, Germany) accompanied by cardiac pacing acquiring a reduced number of low-dose projections (~100-400 Purpose: To demonstrate that myocardial microvessels detection is feasible at high-resolution susceptibility-weighted MR imaging (SWI). Methods and Materials: Fourteen Wistar rats underwent ex vivo cardiac MR imaging on a 4.7 Tesla scanner using a cryogenic device. Thin, tubular hypointensities within the myocardium of normal rat hearts at high-resolution susceptibility-weighted MR imaging (group 1, n=6) were presumed to be intramyocardial microvessels.To prove that these "strand-like" structures were microvessels, a reference map of the myocardial macrovessels (group 2, n=4) after direct intracoronary injection of barium sulphate, a viscous contrast media was defined. Then, a superparamagnetic contrast agent (ferumoxsil, Lumirem ®), an intravascular contrast agent, was injected to stack up the distribution of intramyocardial microvessels (group 3, n=4). For groups 2 and 3, 3D fast imaging with steady state in precession (3D FISP) sequences was performed. The results of images in group 1 (spatial resolution: 39 μm) and group 3 (spatial resolution: 39x39x39 μm 3 ) were qualitatively compared. Results: After intracoronary artery injection of barium sulphate, the main coronary arteries were visible up to the third-order branches (group 2). Beyond this level, the coronary microvasculature was opacified with ferumoxsil (group 3) as demonstrated by the presence of ferumoxsil inside the microvessels on MR-matched histological sections. The regional distribution of microvessels was similar between groups 1 and 3. Conclusion: Myocardial microvessels appear as "strand-like" structures on highresolution MRI without injection of contrast media. This provides new methods for evaluation of neovascularization in preclinical models of myocardial infarction. Purpose: To prospectively compare the image quality and homogeneity of cardiac T2-weighted dark blood images using a dual-source parallel radiofrequency (RF) transmission MR system with RF shimming at 3.0 T and conventional MR imaging at 3.0 T. Methods and Materials: Dual-source parallel RF transmission 3.0 T MR system with local RF shimming was used to obtain T2-weighted dark blood images in 31 patients and compared with standard MRI at 3.0 T. SNR was determined in the interventricular septum (IS), the lateral wall (LW), the right ventricular cavity (RV) and left ventricular cavity (LV) in the anterior wall (AW), posterior wall (PW) and in the left ventricular cavity (LV) in two-chamber orientation. (kerstin.bauner@med.uni-muenchen.de) Purpose: To assess dynamic T1 shortening effects of equimolar doses of gadobutrol and gadoterate meglumine in myocardium and the effect on extracellular volume fractions (ECV) in an animal model. Methods and Materials: 10 rabbits underwent cardiac MRI under general anaesthesia on a 1.5 Tesla scanner using an 8-element knee coil. Exams included SSFP cine imaging as well as pre-and post-contrast myocardial T1-mapping using a modified look locker inversion recovery (MOLLI) technique. Each animal was scanned twice with a 24-h interval after receiving either 0.1 mmol/kg gadobutrol Methods and Materials: Twenty-five breast lesions classified suspicious in mammography or ultrasound (BIRADS 4/5) were included in this prospective IRB-approved study. All patients underwent 7T MRI (Siemens Magnetom, Erlangen, Germany) using a dedicated 4-channel breast coil and a high temporal and spatial resolution 3D T1-weighted sequence (TWIST, fat-sat, 0.7 mm isotropic, temporal resolution 14sec, examination time 9 min) with a single dose of contrast agent (Dotarem, Guerbet). One patient had to be excluded due to insufficient data quality. Two readers trained in different institutions independently assessed lesion morphology and enhancement kinetics and classified them according to BI-RADS. Lesion size, localisation and image quality were assessed. Sensitivity, specificity, diagnostic accuracy and interrater agreement (kappa statistics) were calculated for both observers. The histopathological diagnoses were used as the standard of reference. Results: There were three benign and 21 malignant lesions. Mean histopathological size was 25 mm (range 8-51 mm). On the basis of lesion morphology and enhancement patterns, all lesions were correctly classified as benign (n=3) and malignant (n=21) by 7T CE-MRI. Sensitivity, specificity and diagnostic accuracy were 100%. Interrater agreement for BI-RADS ratings was excellent (0.928). Kappa agreement for single BI-RADS descriptors ranged between 0.709 and 1. Conclusion: High spatial and temporal resolution imaging in clinical practice is feasible using 7T MRI, revealing excellent diagnostic accuracy and interrater agreement. Purpose: To study a potential role of quantitative MRI (qMRI) using T1/T2 ratios to differentiate benign from malignant breast lesions, assess contralateral breast involvement and monitor response to treatment. A cross sectional study of 41 women with 46 breast lesions were scanned with the mixed-TSE pulse sequence, which is multispectral in T1 and T2, therefore, affords maps of T1/T2. Patients were grouped according to histopathological stage of disease: untreated malignant tumor, treated malignancy and benign disease. qMRI assessment of the same quadrant of contralateral breast that did not have cancerous lesion was performed and compared to the breast that was subjected to chemotherapy and/or radiation therapy in order to monitor response to treatment. Results: Elevated T1/T2 means of 6.44 ± 1.05 (N=7) were observed for biopsy proven malignant lesions and 5.98 ± 0.63 (N=21) for malignant lesions that were treated prior to qMRI with chemotherapy and/or radiation as compared to 3.88 ± 0.43 (N=18) for benign lesions. The higher stage of cancer determined by histopathology analysis was also strongly associated with higher T1/T2 ratio (p= 0.0093). Estrogen and progesterone receptors negative status was strongly correlated with higher T1/T2 ratio p=0.060 and p=0.0427, respectively. Her2/neu receptor status showed no significant correlation with T1/T2 ratio (p=0.1506). The T1/T2 ratios provide measures that strongly correlate with histopathological findings. This quantitative information of tissue properties can provide basis for improving the specificity of diagnostic breast imaging and serve as a tool to assess response to treatment and contralateral breast involvement. Improved differentiation of breast tumours using novel imaging system based on co-registered opto-acoustic tomography and ultrasound P. Otto 1 , K. Kist 1 , N.C. Dornbluth 1 , T. Stavros 1 , D. Herzog 1 , B. Clingman 1 , J. Zalev 1 , P. Lavin 2 , A. Oraevsky 3 ; 1 San Antonio, TX/US, 2 Southborough, MA/US, 3 Houston, TX/US (ottop@uthscsa.edu)Purpose: A novel system called Imagio combines ultrasound and opto-acoustics (OA) to more accurately distinguish malignant from benign tumours. We analysed readers' ability to assess probability of malignancy (POM) using OA versus conventional diagnostic ultrasound (DUS) alone. Methods and Materials: 73 patients with breast masses were assessed with OA and DUS. All the masses were biopsied. Histology was the gold standard. OA employs near-infrared laser pulses at two different wavelengths (to provide contrast between oxygenated haemoglobin in benign lesions and de-oxygenated haemoglobin in malignant lesions) to illuminate tissues through a fibreoptic bundle incorporated into a prototype duplex hand-held ultrasound probe. It detects the laser-generated ultrasonic pressure waves that are then used for reconstruction of two-dimensional OA images. OA maps of total haemoglobin and blood oxygen Purpose: To assess metabolic imaging of breast tumours with breast 18 F-FDG PET-CT and compare it with 3 T CE-MRI. Methods and Materials: 159 suspicious breast lesions were included in this IRB-approved prospective study. All patients were examined with 18 F-FDG PET-CT and 3 T CE-MRI of the breast. The MRI protocol consisted of a T2-w and a contrast-enhanced high-resolution 3D-T1-w sequence with a single dose of contrast agent (Dotarem®, Guerbet). All patients were subjected to prone 18 F-FDG PET-CT scanning. CT data were used for attenuation correction. Breast PET-CT was assessed for 18 F-FDG-avidity of lesions. Tumours were classified as positive when 18 F-FDG-uptake was greater than blood-pool activity. Lesions within tissues demonstrating moderate/high physiologic background activity were considered positive if the activity was greater than the adjacent physiologic activity. 3 T CE-MRI was assessed for lesion morphology and enhancement kinetics and classified according to BI-RADS®. All lesions were histopathologically verified. Results: PET-CT had a sensitivity of 96%, a specificity of 76% and diagnostic accuracy of 90%. CE-MRI had a sensitivity of 100%, a specificity of 80% and a diagnostic accuracy of 94%. There were 46 benign and 113 malignant lesions (mean lesion size 26.03 mm; range 5-90 mm). The 5 false-negative lesions in PET-CT were small lesions (mean 11.2 mm), had a very low SUV (mean SUVmax 1.59) or were adjacent to tissue with high physiologic activity or low grade IDCs. Conclusion: 3 T CE-MRI is superior to PET-CT for assessment of breast lesions, but dedicated breast PET-CT is a valid alternative in patients, who are unsuitable for MRI. High spatial and temporal resolution breast imaging at 7 Purpose: To validate a contrast-enhanced (CE) combined high spatial and temporal resolution imaging protocol for the assessment of breast tumours at 7 Tesla in clinical practice. The aim was to evaluate the safety and efficacy of CRA as local therapy for breast carcinomas with bone metastases. Methods and Materials: Sixteen CRA breast lesions, mean size 2.4 (range 0.8-6.7 cm) in thirteen consecutive patients, mean age 52 (36-81) with core-needle biopsy-proven breast carcinoma and bone metastases were enrolled in this study. 10 patients had one lesion and three patients had 2 lesions. Under local anaesthesia and mild conscious sedation, the tumour and surrounding breast tissue were ablated with percutaneous CT-guided CRA. Cryoablation consisted of 2 cycles each of 10 minutes of freezing followed by a 4-min active thawing phase and a 4-min passive thawing phase for each one. Ten patients underwent one CRA session and two patients 2 CRA sessions. One patient is treated with two sessions for the same lesion. Results: All CRA sessions were successfully completed and all breast tumours were ablated. Morbidity consists in transient and mild ecchymotic changes and post-procedural oedema seen in two cases and alteration in skin pigmentation seen in the point of insertion of the cryoprobes in other two cases. The therapeutic outcomes were evaluated by contrast-enhanced TC or MRI at 1-, 3-and 6-month interval. Purpose: Stereotactic vacuum-assisted biopsy (VABB) is the first choice technique to characterise suspicious microcalcification clusters; however, considerable proportion of understaged invasive cancer (IDC) at subsequent surgical histology has been reported. BLES, thanks to a radiofrequency excisional system, remove a larger not fragmented histological sample (25x20 mm, weight 3 g). Our aim was to prospectively assess BLES diagnostic and eventually therapeutic efficiency in a selected cohort of patients with suspicious microcalcification cluster. Methods and Materials: From September 2010, patients with small microcalcification cluster, < 1 cm, staged 4a-4b according to BI-RADS classification system, were proposed for excisional biopsy with BLES. Written informed consent was obtained.Results: Up to now, 80 patients underwent BLES at our centre; 32 of them (40%) had malignant lesion, 7 were IDC and 25 (78%) in-situ (DCIS) carcinoma. Rationale of the study was to completely remove microcalcification clusters, obtaining enough surrounding tissue for histological margins' evaluation. Complete histological concordance was obtained in 100% of atypical hyperplasia. All patients with DCIS underwent surgical excision: upgrading to IDC resulted in only 3/25 (12% underestimation proportion); among DCIS cases, surgical excision demonstrated complete removal of the lesion by BLES in 18/25 patients (72%). Conclusion: In our experience, BLES is a valid, simple and safe alternative to VABB, providing better diagnostic performance evaluated as histologic accuracy with lower underestimation rate compared to previously reported for VABB. In selected cases, particularly in small microcalcification clusters, BLES may represent an interesting new therapeutic strategy considering the high rate of complete lesion removal. Purpose: The objective of the study is to assess the use of "Intact" Breast lesion excision system as the primary method for histopathology diagnosis in suspicious small and borderline lesions as well as the unclassified microcalcifications. Methods and Materials: 58 cases were included (Feb-August 2012). Inclusion criteria: small lesion less than 20 mm, unclassified microcalcifications, asymmetric densities, focal distortion. Results: 52 cases were successfully done, 88.5% (46 /52) cases were done under ultrasound guidance and 11.5% (6/52) cases were done under stereotactic guidance. 38.5% (20/52) lesions were removed using the 15 mm probe and 61.5% (32/52) lesions were removed using the 20 mm probe size. The main indication was complete removal of a small mass (20/52) followed by biopsy of unclassified microcalcifications, either without mass (8/52) or associated with a mass (8/52). Asymmetry and distortion were the indications in (6/52) and finally clustered micro cysts (8/52). As regards the histopathology after total excision; 90.4% (47/52) of lesions were benign and only 9.6% (5/52) of lesions were malignant. Fibroadenoma was the commonly encountered benign lesion in the study group, it was encountered in 38.5% (20/52), followed by papilloma found in 19.3% (10/52), followed First experiences with a self-test for Dutch breast screening radiologists as a quality assurance tool J. Timmers 1 , A. Verbeek 1 , R. Pijnappel 2 , M. Broeders 1 , G. den Heeten 3 ; 1 Nijmegen/NL, 2 Utrecht/NL, 3 Amsterdam/NL (j.timmers@lrcb.nl)Purpose: To evaluate the use of a self-test as a quality assurance tool for screening radiologists in the Dutch breast cancer screening programme. Methods and Materials: 144 screening radiologists were invited to voluntarily complete a test set of 60 screening mammograms. The following grading criteria were assigned regarding the most suspicious lesion: location, level of suspicion, BI-RADS, laterality, type (well defined mass, ill defined mass, spiculated mass, microcalcification clusters, architectural distortion and asymmetric density) and mammographic density are assigned. Also, several reader characteristics, such as years of experience and number of cases read per year, were to be completed. Case and lesion sensitivity and specificity were determined for all readers. The spearman correlation coefficient was used to determine correlation between reader characteristics and performance measured by the area under the receiver operator characteristics (ROC) curve (AUC). Results: 112 radiologists completed the test set (78%). The mean age was 49 (range 33-68) and on radiologists read on average 10,000 (range 700-60,000) screening mammograms per year. The median AUC value was 0.91, case sensitivity 91%, lesion sensitivity was 91% and specificity 94%. The AUC was not correlated to reader characteristics. The test-set revealed interobserver variation in assigning lesion types. Conclusion: Overall, a good performance was seen among all screening radiologists. Readers are able to determine their educational needs and compare it with peers during training or audits. It is therefore a useful quality assurance tool. Medical education should be dedicated to reducing interobserver variation. Transition from analogue to digital screening mammography significantly increases the proportion of women referred twice for the same lesion L.E.M. Duijm, H. Wiersma; Eindhoven/NL (LEMDuijm@hotmail.com) To determine the effect of transition from analogue to digital screening on the proportion of women referred twice for the same lesion and to assess screening outcome. We included 302,912 consecutive analogue screens (obtained between January 2000 and April 2010) and 90,288 consecutive digital screens (obtained between July 2009 and July 2011). Review of the screening mammograms of women who had been referred twice was performed to determine whether their initial and second referral comprised the same lesion. During 1-year follow-up, radiology reports, surgical correspondence and pathology reports of each referred woman were collected. Results: The overall positive predictive value (PPV) of referral was 37.3% at analogue screening and 22.0% at digital screening (P < 0.001). Among women who had only been assessed by analogue screens, 37 (0.9% of referrals) had been referred twice for the same lesion. These referrals included 13 malignancies (PPV 32.4%). Among the 90,288 women who received their first digital screen following one or several previous analogue screens, 52 (1.9% of digital referrals, p < 0.001) were referred again for a lesion for which she had been referred previously at analogue screening. These second referrals included 8 malignancies (PPV 15.4%, p=0.03). Conclusion: Implementation of digital screening significantly increased the proportion of women referred twice for the same lesion. Their PPV was significantly lower than the one found in women who had been referred repeatedly for the same lesion during analogue screening. Purpose: To determine the impact of audits as a quality assurance tool to improve breast cancer screening performance. The Dutch centrally organised breast cancer screening programme offers biennial mammography to women aged 50-75 years. A team of the National Expert and Training Centre for Breast Cancer Screening with peer radiologists conducts audits of all 16 reading units every 3 years as part of the quality assurance programme. Data on screening outcomes are assessed and a on statistical significance and clinical relevance are: age, mass, calcifications, parenchymal deformity and asymmetric density. Conclusion: With our nomogram we developed a tool to assist screening radiologists in determining the chance of malignancy based on mammographic findings. We propose cut-off values for assigning BI-RADS categories in the Dutch screening setting based on our nomogram which will need to be validated in future research. These values can easily be adapted for use in other screening programmes. Purpose: Automated 3D-breast ultrasound (ABVS) is investigated as a six-monthly addition to annual breast cancer screening with MRI+mammography (MM) in highrisk women (LTR> 50%). ABVS, an inexpensive radiation-free technique, allows more frequent screening and temporal comparison. This study assesses effects of additional ABVS examinations at baseline. The study population consists of 234 women in whom ABVS and MM were performed on the same day. All ABVS and MM examinations were read by one of 4 breast radiologist. The recall rate (RR), biopsy rate (BR), cancer detection rate (CDR), sensitivity and specificity of ABVS and MM screening were analysed. Results: Based upon MM, 28 patients were recalled for further examination (RR=12%). With ABVS 12 of these patients were also recalled, as well as 17 other women. Consequently, the RR increased to 45/234. Biopsies were deemed necessary in 21 patients after MM and increased to 26 with ABVS added, an increase from 9%-11%. 17 additional ABVS findings were resolved with targeted ultrasound. In total 4 cancers were found by MM (CDR 1.7%, sensitivity 100%, specificity 89%). Two of these cancers were also detected by ABVS (CDR 0.9%, sensitivity 50% specificity 88%). The two missed cancers were retrospectively visible, but misinterpreted due to post-operative scarring. Conclusion: Adding ABVS to high-risk MM screening increased RR and BR at baseline. Whether these negative effects are reduced when radiologists gain more experience and whether they are balanced by earlier detection of breast cancer due to the six-month interval of ABVS remain to be determined.radiological review is performed (40 interval cancers, 40 screen detected stage-II cancers and 40 consecutive recalled cases). The audit is completed with a report, summarising the results and giving recommendations. This study compares four audit series (1996-2000/2001-2005/2003-2007/2010-2011) . Results: Recall rates (subsequent screens) increased from 6, 10, 12 to 14 per 1000, respectively, in the four series. Detection rates also increased from 3.3, 4.3, 4.7 to 5.7 per 1000. Distribution of tumour size and lymph-node status of invasive tumours remained stable (p=0.4). The percentage interval and screen-detected stage II cancers classified as "missed" during the review did not change (22% to 25%, p=0.1). Review of consecutive recalled cases showed an increasing number of cases the audit team would not have recalled with a higher recall rate of the screening radiologists. Conclusion: We found audits are helpful in controlling the balance between (false positive) recalls and detected breast cancers. It also serves as a learning and feedback tool as it triggers discussion between screening radiologists. Overall, it can be seen as an important quality assurance tool. Purpose: According to current Dutch guidelines, all women following a positive screening mammogram are referred for a full hospital assessment including surgical outpatient clinic and radiology department. Till 2007, all women with a positive screening mammogram in our screening region were only referred for further assessment to our radiology department. Purpose of this study was to determine how often surgical consultation in women with a positive screening mammogram could be avoided by a radiological pre-assessment. Methods and Materials: All women with a positive screening mammogram, n=1014, referred to our radiology department from 2002 to 2007 were included. Data were prospectively collected by a senior breast radiologist. In-hospital follow-up data were available till September 2012. Descriptive statistics were used. Percentage of patients only assessed by a radiologist was determined. Negative predictive value for malignancy was calculated from the in-hospital follow-up. Results: 427 of 1014 women (42%) were only assessed at the radiology department without further surgical consultation. During follow-up, 8 of these 427 women (2%) developed a malignancy in the same breast. At least 6 of these malignancies were located at a different location than the original screening findings which led to the initial referral. The estimated negative predictive value for malignancy was 99.5%. Conclusion: By referring women with a positive screening mammogram to the radiology department for a pre-assessment, a surgical consultation was avoided in 42%, with an estimated negative predictive value for malignancy of 99.5%. Purpose: To determine the ability of T1 mapping of liver on Gd-EOB-DTPAenhanced MR imaging (MRI) for estimating liver function and to compare the estimated liver function to the model for end-stage liver disease (MELD) score. Methods and Materials: 24 patients underwent Gd-EOB-DTPA-enhanced MRI on a 3 T system. Patients were classified into two groups: MELD score < 9 (n=15) and MELD score ³9 (n=9). Two TurboFLASH sequences (TI = 400 ms, 1000 ms) were acquired before and 20 minutes after Gd-EOB-DTPA administration to obtain T1 maps. T1 relaxation times were determined indicating Gd-EOB-DTPA liver-uptake and correlated to the MELD score. Results: Significant changes between T1 relaxation times of non-enhanced MRI (794 ms ±136 ms) and Gd-EOB-DTPA-enhanced MRI (351 ms ± 141 ms) were observed (p < 0.001). T1 relaxation time for non-enhanced MRI showed no significant differences (p=0.387) between the group with MELD score < 9 (776 ms ± 157 ms) and the group with MELD score ³9 (824 ms ± 90 ms). After administration of Gd-EOB-DTPA T1 relaxation time of patients with MELD score < 9 (284 ms ± 104 ms) and patients with MELD score ³9 (465 ms ±123 ms) shows a significant difference (p=0.002). The shortening of T1 relaxation time was significantly lower for patients with a higher MELD score (p=0.002). Conclusion: Patients with advanced liver disease showed significantly lower changes in T1 mapping. Therefore, evaluation of changes in T1 mapping of the liver parenchyma may serve as a useful method to determine whole liver function, to improve the estimation of segmental liver function and finally to define the grade of liver disease. Liver dysfunction induced by amiodarone therapy: evaluation by sequential CT studies Y. Sonoyama, T. Tajima, T. Shiga, N. Hagiwara, S. Sakai; Tokyo/JP (y-sonoyama@rad.twmu.ac.jp)Purpose: To evaluate the relationship between the sequential changes of CT attenuation of the liver (CTL) and liver damage after administration of amiodarone (AMD) for treatment of refractory ventricular arrhythmias. This was a retrospective study of 45 patients (26 men, 19 women: age range 19-89, mean 59) with AMD administration. Serum level of drugs (AMD and desethylamiodarone (d-AMD), a metabolic product of AMD), the percentage of rises in serum alanine transaminase (ALT) level (ALT%) and total administered dose of AMD at evaluation CT were evaluated and compared with the CTL. As regards to 23 patients who underwent CT before the initiation of AMD administration, the medication periods and total administered doses of AMD were compared with changes in CTL.Results: There was a mild correlation between CTL and mean medication period (p=0.0238, r=0.337). There was a strong correlation between CTL and serum level of AMD (p < 0.0001, r=0.699), whereas there was a moderate correlation between CTL and serum level of drugs (AMD) (p < 0.0001, r=0.574). There were significant correlations between total doses of administered drug and the CTL (p=0.0008, r=0.480) and between ALT% and the CTL (p=0.0078, r=0.420). Conclusion: CTL was demonstrated to correlate with total administered doses of AMD, ALT%, medication periods and serum level of drugs, especially of d-AMD. Serial changes in CTL can be a sensitive less-invasive biomarker in patients treated with AMD. The estimated population dose per caput is 1 mSv, which is lower than corresponding dose in USA (3 mSv) or in Australia (1.7 mSv). The highest average contribution is from CT, 56 %. From plain radiography, fluoroscopy and interventional radiology the proportional fractions are 19%, 17% and 7.5 % respectively. From diagnostic nuclear medicine procedures, the estimated mean effective dose per caput is 0.036 mSv. Heart and bone examinations contribute 40% and 36%, respectively. Conclusion: There were high variations between countries in frequencies (for example, in thorax radiography about ten-fold between Spain or Portugal and Germany) and typical effective doses (for example, in CT head four-fold between Denmark and Luxembourg). This presentation will review the available data in Europe using graphs in which countries can be identified. Furthermore, the procedures contributing most to the population dose are highlighted. Purpose: To assess the feasibility of the volumetric estimation of the left liver lobe, with 3D ultrasound, with MRI comparison and surgical specimen. Methods and Materials: The data of 19 consecutive patients referred for giving their left liver lobe to a child were reviewed (living donor transplantation program). The measurements of the 3D volumes of the segments II and III were performed retrospectively with comparison of the same evaluation performed with MRI (the reference and routine technique for the preoperative assessment of the liver size). All the examinations were done twice by 2 experts radiologists and radiologists in training. The results were statistically analysed (variance test, Gage R&R and Bland-Altman). 3D and MRI measurements were compared and related to surgically proved volume quantification. Results: Intra-and inter-observators reproducibility was poorly conclusive (for US and MRI): gage R&R analysis is related to a PRR of 57% for US and 54% for MRI. Bland-Altman analysis was giving an underestimation of volume measurements with US (bias from -11 ml to -44 ml). Agreement limits (-1.96SD to +1.96SD) for the 4 observators were included between -174.3 ml and +103 ml (from -71.6% to + 43.5%). Conclusion: Correct estimation of the left liver lobe volume performed with 3D or MRI is related to a low repeatability and a low reproducibility for both techniques. Bland-Altman analysis is also related to significative differences of volume measurement in both techniques. An accurate formula for a quick estimate of liver volume in polycystic liver disease M. Chrispijn, T.J.G. Gevers, J.P.H. Drenth; Nijmegen/NL (melissachrispijn@gmail.com)Purpose: Polycystic liver disease (PLD) patients have severe hepatomegaly. Primary aim of treatment is total liver volume (TLV) reduction. The gold standard to assess TLV is CT volumetry which involves manual delineating of the liver outline. This is time consuming and requires expertise. There is a clear need for an easy and fast approach to estimate TLV in routine practice. Methods and Materials: All PLD patients with ³1 CT scan were considered for inclusion. We measured the liver in transverse (T), anterioposterior (AP) and craniocaudal (CC) directions and performed CT liver volumetry. We had access to an inception and a replication cohort. We performed multiple linear regression to predict TLV using the three dimensions in the inception cohort. Liver volumes were transformed logarithmically. The goodness of fit of the prediction model was assessed and stated as R 2 . Finally, we validated the prediction model in our replication cohort. Results: The inception cohort included 54 PLD patients (median TLV 3890 mL (range 1084-13611 mL)). All three diameters were significantly correlated with TLV (p < 0.001). The linear regression model resulted in the following formula: predicted TLV = 4,179+(0.009*T)+(0.007*AP)+(0.001*CC). Our model predicted TLV accurately in the inception cohort (R 2 =0.907 Adjusting and measuring CT dose in severely obese patients R. Marcus, F. Bamberg, K. Neumaier, M.F. Reiser, T.R.C. Johnson; Munich/ DE (roy.marcus@med.uni-muenchen.de) Purpose: CT in morbidly obese patients remains a challenge with respect to dose and image quality. Automatic adaptation of parameters results in high dose length products which do not reflect the actual dose due to the shielding by the fat. Aim of this study was to determine the actual dose and image quality. Methods and Materials: An Alderson phantom was equipped with 116 thermoluminiscent detectors. Scans were performed using three set-ups: (I) 'Obese' phantom in 30-cm circumferential fat (simulating 175 cm/300 kg patient) with a dual--source protocol at 2x140 kVp with current modulation; (II) Obese phantom with automatic potential and current modulation; (III) Slim phantom with automatic potential and current modulation; dose was calculated according to IRCP-103 and based on DLP. Image quality was assessed subjectively and by image noise. Patient-specific whole body voxel model for accurate Monte Carlo CT dose estimation N. Saltybaeva, Y. Smal, D. Kolditz, W. Kalender; Erlangen/ DE (natalia.saltybaeva@imp.uni-erlangen.de) Purpose: The accuracy of CT dose estimates based on Monte Carlo (MC) techniques is limited as data is only available for the scanned volume. The purpose of this study was to generate and to validate whole body voxel models using the patient CT images extended by established voxel phantoms. Methods and Materials: Measurements were performed on a SOMATOM Definition Flash scanner (Siemens, Forchheim, Germany) using the anthropomorphic Rando-Alderson phantom. The absorbed dose was measured using a set of 90 calibrated thermoluminescent dosimeter (TLD) chips for thorax protocols with tube voltage of 80, 100 and 120 kV. Whole body voxel models were built as a combination of the patient CT images and the ICRP Adult Male Reference voxel phantom. MC simulations were performed using the ImpactMC software (CT Imaging GmbH, Erlangen, Germany) for only the scanned volume and for the combined whole body model. Measured and simulated dose values were compared for each TLD chip. Results: At 120 kV, the dose values obtained by MC simulations based on only CT images differed from TLD measurements by 19% on average with a maximum difference of 37% for the border slices, while the whole body model allowed for a mean difference of 6%. The difference between measured and calculated results was reduced by 53%, 60% and 68% for 80, 100 and 120 kV, respectively, when using the whole body voxel model instead of the CT-scanned volume only. The proposed whole body voxel model for Monte Carlo simulations significantly improves the accuracy of patient-specific CT dose estimates. Purpose: Accurate patient dose estimation using CT imaging is important particularly as the modality is being increasingly used. Body habitus varies and the use of Monte Carlo simulations for "standard man" phantoms does not provide accurate dose estimation for non-standard patient sizes. The study proposes an algorithm for dose estimation for an individual patient from simulated data from mathematical phantoms. The algorithm interpolates doses simulated for ORNL mathematical phantoms accounting for differences on patient and phantom sizes. Four patient models were produced using 2 anthropomorphic phantoms (representing 1-and 5-year-old children) with and without an additional fat-equivalent layer. All phantoms were scanned at 80 and 120 kV (trunk protocol). Doses were measured with 60 TLD dosimeters. Additionally, DICOM images were segmented for organs and data were used as input for dose simulation. All simulations were performed with validated tool (ImpactMC). Doses for phantoms and patients were estimated from the MC simulations using the proposed algorithm. Calculated and measured doses were compared. The algorithm improved accuracy in dose estimation by 49, 35, 30, and 21% for small thin, small thick, large thin and large thick phantom sizes, respectively, compared with estimates based on ORNL phantoms only. For patient data the accuracy in lung dose estimates improved from 15 to 4%, and from 108 to 15%, for 2-and 6-year-old patients, respectively. Conclusion: The proposed algorithm improves dose estimation accuracy for individual paediatric patients. It is simple and suitable for implementation in software tool for dose calculation. Purpose: The combined availability of DICOM radiation dose structured report and active personal dosimeters in interventional radiology (IR) can support the optimisation of radiation protection, both of patient and staff. Methods and Materials: For nine months, interventionalists performing interventional cardiology procedures have used a personal active dosimeter (DoseAware, Philips) worn over the apron. Information is displayed in real-time and transmitted to a database. The patient dosimetry report (Allura FD10, Philips) has been also automatically collected for all procedures. A Matlab routine integrates both information on procedure data and patient and staff exposures, providing a tool aiming to identify high and/or non-optimised exposures.Results: On a sample of 45 coronary angiography and percutaneous angioplasty procedures the derived mean KAP (SD, maximum) per procedure was 69.0 (53.1, 236.2) Gycm 2 . The first operator mean (range) personal equivalent dose was19 (0.65 ÷ 27.3) µSv/procedure. The mean (SD) scatter equivalent dose measured on the C-arm at the machine isocentre level per unit of KAP was 2.32 (0.50) µSv/Gycm 2 . The availability of the DICOM structured patient dosimetry report and the technology advancement of personal dosimetry can conveniently support the optimisation radiation protection process in IR. The described experience supports the initiative of ISEMIR project (IAEA, Austria) that recommends the development of active dosimetry technology for a better monitoring of operators in IR and the development of a DICOM operator structured dosimetry report as prerequisite to define and develop software platforms aiming to combine patient and staff exposure information.14:00 Purpose: The purpose of this study was to evaluate the additional diagnostic benefit of high-resolution steady state VIBE imaging in peripheral MRA. In this retrospective IRB-approved study 224 patients (72 women, 152 men, age 67.3±13.9) were included who had undergone a peripheral MRA exam after injection of 0.1 mmol/kg gadobutrol including a large field of view MRA, time-resolved MRA of the calf station and steady state 3D VIBE sequence (3 T Siemens TimTrio, 1.3 mm isotropic spatial resolution, PAT 3, 1:26 min Tacq per station) prior to the time-resolved MRA. One board-certified radiologist rated image quality of the VIBE sequences on an ordinal three-point scale and analysed the images for additional diagnostic findings. Descriptive statistics and demographic patient data were used for further evaluation. The image quality of the VIBE sequences of the pelvis, upper and lower leg was excellent in up to 88%, 84% and 47%, respectively. Poor image quality was only detected in the upper (2%) and lower leg (6%). The VIBE sequence yielded an additional diagnostic benefit in 44% of the patients overall. There was no significant difference in terms of additional findings between men and women (46% and 40%, p=0.4601). The patient sample revealed a distribution of 59% inpatients and 41% outpatients with additional pathology found in approximately 44% for each group. Conclusion: Steady-state 3D VIBE sequences in peripheral MRA yield additional relevant diagnostic findings in 44% and above in patients older than 60 years irrespective of gender and patient status.Author Disclosures: H.J. Michaely: Consultant; Bayer Healthcare. In set-up III, measured and calculated dose agreed well (3.05 vs. 3.0mSv). Set-ups I and II showed a discrepancy of 72% between measured and calculated dose (9.52 vs. 34.20mSv and 10.69 vs. 37.43mSv). Image quality in set-ups I and II was rated sufficient, compared to the excellent image quality in set-up III. Set-up.i. showed a lower image noise (9 vs. 33 HU) and lower dose (12%) than set-up II. Conclusion: Morbidly obese patients receive higher dose in CT examinations, which is required to achieve diagnostic image quality. Calculations based on DLP and standard conversion factors overestimate the dose by approx. 70% in 300 kg patients, while the actual equivalent dose remains within the reference limits. The effects of head size/shape, head positioning, and bow-tie filter selection on peak tissue doses from brain perfusion 256-slice CT K. Perisinakis 1 , I. Seimenis 2 , A. Tzedakis 1 , A.E. Papadakis 1 , J. Damilakis 1 ; 1 Iraklion/GR, 2 Alexandroupolis/GR (Kostas.Perisinakis@med.uoc.gr) Purpose: To determine peak doses to skin, eye lens, brain parenchyma and cranial red bone marrow (RBM) of adult individuals subjected to low-dose brain perfusion 256-slice CT studies, and investigate the effects of patient head size/shape, head position and bow-tie filter selection. Methods and Materials: Peak doses to radiosensitive tissues were measured in 106 individual-specific head phantoms subjected to the standard low dose brain perfusion CT on a 256-slice CT scanner using a novel Monte Carlo simulation software. The effects of head size/shape, head position during acquisition and bow-tie filter on resulting peak doses were investigated. The effects of head mis-centering and use of narrow bow-tie filter on image quality were assessed. The mean peak doses to eye lens, skin, brain and RBM were found to be 124, 120, 95 and 163 mGy, respectively. Patient head size/shape was found to have minimal effect on peak doses, since maximum differences were less than 7%. Bow-tie filter selection and head mis-centering were found to have a considerable effect on peak tissue doses with minimal image quality deterioration. The use of the narrower bow-tie filter available resulted in 35% reduction of peak tissue doses. Conclusion: Typical peak doses to skin, eye lens, brain and RBM from the standard low dose brain perfusion 256-slice CT exposure are well below the corresponding thresholds for induction of deterministic effects. The use of narrow bow-tie filters may considerably reduce peak absorbed dose to all above radiosensitive tissues with minimal degradation of image quality. Detector dose vs image quality in radiography with digital detectors: a visual grading analysis R. Decoster, H. Mol, D. Smits; Brussels/BE (robin.decoster@hubrussel.be)Purpose: The introduction of digital detectors in the radiology predicted a dose reduction. Due to the dynamic range, radiographs of sufficient quality can be produced with a lower detector air kerma (DAK). However, this reduction was not observed. Some authors indicate a creep toward higher DAK, explained by better appreciation of the radiographs due to a higher contrast-to-noise ratio. To investigate the relation between the DAK and the appreciation of image quality by radiologists, 172 anterior-posterior (AP) radiographs of the knee and 152 radiographs of the pelvis where collected randomly in 19 radiologic centres. A visual grading analysis (VGA) with a five-point scale was used to judge the image quality of seven anatomic structures. The mid-point of the scale was equalised to diagnostic image quality. Six radiologists scored both datasets, in a controlled environment, with ViewDex®. Every observer received an instruction and a training dataset. To determine intra-observer variability twenty radiographs were repeated. Results: The intra-observer variability was not significant (p> 0.05) in both datasets. The knee AP obtained a VGA score of 3.92, the pelvis obtained VGA score of 3.71. In both cases, the inter-observer correlations are high and significant. The correlation between the VGAS and the DAK (CR 1.54µGy-5.48µGy; DR 0.38µGy-6µGy) was not significant in either dataset. Neither were other analyses based on technical parameters. The VGA revealed a mean image quality higher than diagnostic necessary. Based on the DAK, an overexposure is suspected. The relation between the DAK range and the appreciation of the radiograph needs further investigation. (m.a.m.Dekker@rad.umcg.nl) Purpose: Skin autofluorescence (AF) is a non-invasive marker for advanced glycation endproducts (AGEs) and predicts cardiovascular disease (mortality) in diabetes and renal disease. We examined whether skin AF is increased in subclinical atherosclerosis and whether it is associated with the degree of atherosclerosis independent of diabetes and renal function. Methods and Materials: Cross-sectional study of 223 patients referred for primary (PP;N=163) or secondary (SP;N=60) prevention. Skin AF was measured using the AGE-reader and the degree of atherosclerosis was assessed based on ultrasonographically detected plaques in carotid and femoral arteries (in PP only), and computed tomography-derived coronary artery calcium score (CACS .12], respectively; P = 0.005 and < 0.001). In controls and PAD, skin AF was higher in those with CRP above median compared with below. In a multiple regression analysis, the association of skin AF with the 3 atherosclerosis categories was independent of age, gender, diabetes, Framingham Risk score, and kidney function. Conclusion: Skin AF is increased in subjects with subclinical and clinical atherosclerosis, independently of known confounders. These data suggest that AGEs are associated with the burden of atherosclerosis. Author Disclosures: A.J. Smit: Founder; DiagnOptics. Evaluation of metabolic changes within the normal appearing grey and white matters in children with growth hormone deficiency: magnetic resonance spectroscopy and hormonal correlation J. Bladowska, A. Zimny, A. Zacharzewska, T.M. Gondek, A. Banaszek, T. Żak, A. Noczyńska, M. Sąsiadek; Wroclaw/PL (asia.bladowska@gmail.com) Purpose: The pathogenesis of idiopathic growth hormone deficiency (GHD) in children, including possible cerebral metabolic alterations, remains unclear. The aim of the study was to evaluate the metabolic changes within the normal appearing brain in children with GHD using MR spectroscopy (MRS) and to correlate MRS measurements with hormonal concentrations. Methods and Materials: Seventy-one children with GHD (mean age 6.9 yrs) and 11 healthy controls (mean age 8.4 yrs) were enrolled in the study. The MRS examinations were performed on 1.5 T scanner. Voxels were located in the posterior cingulate gyrus (PCG) and the left parietal white matter (PWM). The NAA/Cr, Cho/Cr and mI/Cr ratios were analysed in both groups. There were also evaluated correlations between the metabolite ratios and hormonal concentrations: growth hormone (GH) in two stimulation tests and GH during the night, as well as IGF-1 (insulinlike growth factor) and IGFBP3 (insulin-like growth factor-binding protein) levels.Results: There was statistically significant (p < 0.05) decrease of the NAA/Cr ratios in PCG and PWM in children with GHD compared to the normal subjects. Other metabolite ratios showed no significant differences. We found also statistically significant positive correlations between NAA/Cr ratio in PWM and IGFBP3 level, as well as GH concentration in stimulation test with glucagon. The reduction of NAA/Cr ratios may suggest loss of neuronal activity within normal appearing grey and white matters in children with GHD, thus MRS could be sensitive marker of cerebral metabolic disturbances associated with GHD and additional indicator for therapy with recombinant GH. Purpose: The microstructure of tissues and white matter tracts in vivo may be studied with DTI. The alterations involving the cerebral cortex associated in various degrees with subcortical white matter abnormalities often affect the projection white matter tracts. The white matter in cortical brain abnormalities is evaluated with diffusion tensor imaging (DTI) and Tract-Based Spatial Statistics (TBSS). Methods and Materials: 65 patients (1year-14year range) 39 males and 26 females) with different pattern of cortical alterations were studied. The DTI data was processed in FSL. For each DTI exam, brain extraction only of images with b value equal to zero was performed so that a mask of entire brain was created. Gadoxetic acid-enhanced hepatobiliary phase MRI and high b-value diffusion-weighted imaging (DWI) in the differential diagnosis between benign to malignant liver lesions P. Arcuri, G. Fodero, S. Roccia, S. Molica, V. Arcuri; Catanzaro/IT (arppaolo@alice.it)Purpose: The aim of our experience was to evaluate the value of gadoxetic acidenhanced hepatobiliary phase imaging and high b-value DWI in the differential diagnosis between benign and malignant liver lesions. Methods and Materials: Twenty-four malignant liver lesions (fourteen small HCC and ten metastatic lesions) and twelve benign lesions (five FNH, four adenomas and three regenerative nodules in cirrhotic liver) were studied. A retrospective evaluation was made. The qualitative analysis was obtained by the evaluation of two radiologists of the lesions's signal intensity compared with that of the surrounding liver parenchyma on hepatobiliary phase images and DWI (b-value=600s/mm2). The contrast-to-noise ratio (CNR) and relative contrast enhancement of lesions on hepatobiliary phase images and the apparent diffusion coefficient (ADC) values were assessed (by ROIs) for quantitative analysis. Statistical analysis was performed by the Mann-Whitney U test. P value less than 0.05 was considered statistically significant. In the qualitative analysis, nineteen malignant lesions (79%) and three benign lesions (25%) were hypointense on hepatobiliary phase images; five malignant lesions (21%) and nine benign lesions (75%) were iso-or hyperintense in the same phase. Twenty malignant lesions (83%) and four benign lesions (33%) were hyperintense in DWI; four malignant lesions (17%) and nine benign lesions (75%) were iso-hypointense in DWI. In the quantitative analysis the mean relative contrast enhancement ratio of the malignant lesions was higher than that of benign lesions. Conclusion: Hypointensity on gadoxetic acid-enhanced hepatobiliary phase images and hyperintensity on DWI (b-factor=600 s/mm2) suggest malignant lesions rather than benign hepatocellular nodules. Gadoxetic acid-enhanced MRI of the liver: correlation between Gadoxetic acid uptake and serum hepatic enzymes levels E. Talakic Purpose: To evaluate observer performance involving absolute visual grading analysis of image criteria using visual grading characteristic curves (VGC) and ordinal regression analysis during CT examination optimisation. Methods and Materials: Images obtained from current and optimised head CT protocols (n=120) from 4 suites were presented using ViewDex on Advantage Workstations for evaluation by radiologists (n=6), grading the visibility of anatomical structures sourced from the European guidelines on quality criteria for CT. Results: VGC analysis in terms of the area under the curve showed no significant differences (p> 0.05) from the 0.5 threshold value, indicating similar image quality between data sets. Ordinal regression analysis indicated no significant (p> 0.05) change in image quality in suites 1 and 3 but discriminated between the data sets for suite 2 and 4 (p < 0.05). Analysis on individual criteria indicated a difference (p < 0.05) in image quality between the protocols for all criteria in suite 2 but no difference (p> 0.05) in suite 4. Discussion: VGC curves demonstrated general trends between protocols. Findings of ordinal regression analysis not only indicate significant differences in image quality but also identify specific anatomical criteria contributing to those differences. The importance of selecting the most appropriate method of analysis in optimisation techniques is highlighted as findings influence protocol implementation based on clinical requirements. Conclusion: An overall 15% radiation dose saving was achieved as a result of optimisation of the head CT protocols. Optimised protocols were implemented for initial diagnosis for three suites and only for follow-up cases excluding initial diagnosis for the remaining suite.14:00 Measuring hepatic functional reserve using low temporal resolution Gd-EOB-DTPA dynamic contrast-enhanced MRI: a comparison study with galactosyl-human serum albumin scintigraphy and indocyanine green retention K. Saito 1 , J.R. Ledsam 2 , S.P. Sourbron 2 , T. Hashimoto 1 , Y. Araki 1 , S. Akata 1 , K. Tokuuye 1 ; 1 Tokyo/JP, 2 Leeds/ UK (um07jrl@leeds.ac.uk) Purpose: To investigate if tracer kinetic modelling of low temporal resolution dynamic contrast-enhanced (DCE) MRI with gadoxetic acid (Gd-EOB-DTPA) has the potential to replace technetium 99m galactosyl human serum albumin (GSA) scintigraphy and indocyanine green (ICG) retention for the measurement of liver functional reserve. Methods and Methods: 28 patients (18 males, 10 females; mean age 67y) awaiting liver resection for various cancers underwent DCEMRI, GSA-scintigraphy and ICG as part of routine pre-operative evaluation. Examinations were conducted within a single month. Underlying liver disease was present in 4 patients. The Gd-EOB-DTPA MRI sequence acquired 5 images: pre-contrast, double arterial phase, portal phase, and 4 minutes after injection. GSA-scintigraphy images were acquired every 10s following contrast injection. Contrast uptake rate (UR) and extracellular volume (Ve) were calculated from DCE-MRI, and the ratio of GSA radioactivity of liver to heart-plus-liver and percent of contrast uptake at 15 minutes (LHL15 and LU15, respectively) from GSA-scintigraphy. ICG retention at 15 minutes, Child-Pugh cirrhosis score (CPS) and post-operative Inuyama fibrosis biopsy criteria were also recorded. Statistical analysis was with SPSS17. Purpose: To investigate dynamic contrast-enhanced computed tomography (DCE-CT) for monitoring the effects of regorafenib on experimental colon carcinomas in rats by quantitative assessments of tumour microcirculation parameters with immunohistochemical validation. Methods and Materials: Colon carcinoma xenografts (HT-29) implanted subcutaneously in female athymic rats (n=25) were imaged at baseline and after a one-week treatment with regorafenib by DCE-CT (128 slice dual source CT). The therapy group (n=13) received regorafenib daily (10 mg/kg bodyweight) via gavage. Quantitative parameters of tumour microcirculation (plasma flow, mL/100 mL/min), endothelial permeability (PS, mL/100 mL/min), and tumour vascularity (plasma volume, %) were calculated using a 2-compartment uptake model. DCE-CT parameters were validated with immunohistochemical assessments of tumour microvascular density (CD-31), tumour cell apoptosis (TUNEL), and proliferation (Ki-67). Results: Regorafenib significantly (p < 0.05) suppressed tumour perfusion (12.8±2.3 to 8.8±2.9 ml/100 ml/min) and tumour vascularity (15.7±5.3 to 5.5±3.5 ml/100 ml/min). Significantly lower microvascular density was observed in the therapy group (CD-31; 48±10 vs. 113±25, p < 0.05). In regorafenib-treated tumors, significantly more apoptotic cells (TUNEL; 11,844±2,927 vs. 5,097±3,463, p < 0.05) and significantly less proliferating cells (Ki-67; 4,277±1017 vs. 4,841±1,593, p < 0.05) were observed. DCE-CT tumour perfusion and tumour vascularity correlated significantly (p < 0.05) with microvascular density (CD-31; r=0.84 and 0.66) and inversely with apoptosis (TUNEL; r=-0.66 and -0.71). arterial phase, portal venous phase, hepatovenous phase, equilibrium phase, and hepatobiliary phase which was 20 minutes after Gadoxetic administration. A test bolus was used to optimise the contrast injection protocol. Signal intensity of the liver parenchyma in all phases was defined using region-of-interest (ROI) measurements for enhancement calculation. Serum hepatic enzyme levels (bilirubin; cholinesterase, CHE; aspartat-aminotransferase, AST; alanine-aminotransferase, ALT; gamma-glutamyl-transpeptidase, GGT; alkaline phosphatase, AP) were available in all patients. Spearman correlation test was used to test the correlation between liver enhancement during the different phases and serum hepatic enzyme levels.Results: At late time points after contrast injection all serum hepatic enzymes were correlated with liver enhancement. Bilirubin and CHE showed stronger correlations than the other serum hepatic enzymes and they became correlated at earlier time points. The strongest correlation was observed between bilirubin and enhancement during the hepatobiliary phase and between CHE and enhancement during the hepatobiliary phase. Bilirubin showed negative and CHE showed positive correlation. The Spearman correlation coefficient was -0.64 for bilirubin and 0.61 for CHE. Conclusion: In gadoxetic acid-enhanced MRI of the liver gadoxetic uptake during the hepatobiliary phase is strongest correlated with bilirubin and CHE serum levels, whereas the other serum hepatic enzymes show weak or moderate correlations. Purpose: Aim of the study is to evaluate the use of MRCP using hepatospecific contrast media (GD-EOB-DTBA) to confirm biliary leak suspect and treatment planning. Methods and Materials: 13 consecutive patients (7 males, 6 females -average age 64 years), during 13 months (April 2011 to May 2012) underwent MRCP study using GD-EOB-DTBA due to clinical suspect of biliary leak. Using an 1.5 T MRI scanner, T1-weighted 3D GRE pulse sequences before and in hepatospecific phase, after GD-EOB-DTBA injection, were performed. All patients with biliary leak underwent endoscopic, interventional radiology (IR) or surgical approach for treatment. Results: Biliary leak was clinically suspected in 13 patients and underwent abdominal surgery (7 laparoscopic cholecystectomy, 5 various hepatic resections, 1 resection of a pancreatic-duodenal mass) after 33 days (AV; range 4 to 107). In 11/13 biliary leak was found at 44 minutes (AV; range 20 to 76 minutes) from GD-EOB-DTBA injection, from intrahepatic ducts (6/11) site, cystic duct stump (2/11), both intrahepatic and principal biliary duct (2/11) and from a biliodigestive anastomosis (1/11). Biliary leak was confirmed and successfully treated by percutaneous transhepatic cholangiography (8/11), endoscopic approach (1/11), IR and endoscopic "rendez-vouz" technique (1/11) and by surgical laparotomy (1/11). In 2/13 patients, no biliary leak was found and only clinical monitoring was performed, with good outcome. Any adverse reaction or technical problem occurred during the MRCP examination. Conclusion: MRCP with GD-EOB-DTBA is an high sensitivity, safe and fast examination to confirm the suspect and to locate precisely a biliary leak, concurring best planning for treatment. N-acetylcysteine for the prevention of contrast-induced nephropathy in rats M.F. İnci 1 , I. Şalk 2 , O. Solak 2 , Ü. Vurdem 3 , R. İnci 1 ; 1 Kahramanmaraş/TR, 2 Sivas/TR, 3 Kayseri/TR (drfatihinci@gmail.com)Purpose: To date, there is no effective treatment of contrast-induced nephropathy (CIN). N-acetylcystein (NAC) has yielded some promising results recently in the prevention of CIN. In this study, the structural effects of NAC on CIN were analysed. Methods and Materials: Forty adult Wistar albino male rats were randomly allocated to four groups. The first group was the control group (n=9) which received only distilled water; second group was the contrast group (n=10) which received CM; the third group was the contrast plus NAC group (n=8) which received CM and was treated with NAC; and the last group was NAC group (n=10) which received only NAC. At the end of the 3 rd day, the right and left kidneys were removed and reserved for histopathological examination. All tissue sections were examined with light microscope looking for histopathological changes by the same experienced pathologist, without knowledge of the prior treatment. Histopathological examination was conducted in a blinded fashion, and glomerular injury scores, arteriolar injury scores and tubulointerstitial injury scores were calculated. Results: There was a significant difference among the scores of glomerular injury, arteriolar injury and tubulointerstitial injury in all groups (p < 0.05).The scores of glomerular, arteriolar and tubulointerstitial injury of the group-1 and group-4 were not significantly different from each other (p < 0.05). Renal injury scores in group-3