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BY VARIOUS AUTHORS. EDITED UY WILLIAM CAMPBELL POSEY, A.B., M.D. I KuKKS.'.llR IIP OPHTHALMOLOGY IN TH« PHILADCU'HIA TOLVCUNIC ; SIROEON TO TH« WIL1.« KV« HO'I'ITAL; OI'HTHALMIC SI'KQEON TO THP. HOWAKD AND KPM.EPTK HOSI'ITALS ; MEMBEK OP THE AMEKH AN' OPHTHALMOIXX.ICAL SOCIETY, AND JONATHAN WRIGHT, M.D., irrKSlllNU LARYSUOLOUl>r TO K1NU3 COUNTY HOSITTAL i LARYNGOI/XilST TO THE BROOKLYN EVE AM> EAR HO^I'ITAL ; SIRGEON TO Tl ' MANHATTAN EYE AND EAR HOSPITAL, THROAT 1>K1>AI;IMKNT: PATHiM.OUIST TO THE MANHATTAN EYE AND EAR HOSPITAL. ILLUSTRATED WITH 650 ENGRAVINGS AND 35 PLATES IN COLORS AND MONOCHROfylE. ('M«fiiCAL FACULTY ^\ M«QILL LEA BROTHERS «fe CO., PHILADELPHIA AND NEW YORK. ] 903. 1 Entered .ccording to the Aol of Congrew, in the year I»02, bv LEA BROTHERS ± CO., In the Office of the Librarian of Congre... All righU reserved. ,o'=\ D0RN4N, PRIJITEIl. PREFACE. Tin: practical convenience affor^lcd by cdinhiiiing the sui)jects of the Kve, I.'ar, Nose, and Tliioat within a single volume needs no demonstration. It rests upon obvious reasons. The anatomical and patholfigical relations of these organs .-ire so close that the speci.iiist in one subject shonhl have a thorough knowledge of the others: their aHections are so connnon anil widespread that they form ,1 large share of general jjractice, and their bearings upon inter nal medicine are ,so nianifold ,,iid direct tliat no i)hysician can igiuu. their influence or dispenx" with the light they cast upon morbid st.'ites elsewhere. The present volume has been arninged in view of the.se facts and in Older to give a comprehensive, authoritative, and practical expo- sition of these cognate de|)artment«!. The contril)iitors are men who h.Mve demonstrated their .s])i'cia! ability in connection with the subjects a.ssigned. It may be noted that the matter has fM-en distributed so that each author has been enabled to treat the subject committed to him in its entirety. KeiH>titioii, .so frequent a fault in systems, has thus been avoideil. Separate chapters on anatomy and physiology have been omitted, as such general knowledge is presuj)posed ; but enough information will be found in connection with each subject to exj)lain the pathology and symptomatology. The authors have aimed to adai)t the book particularly to the needs (,f general practitioners and students, though it is hoped that even specialists may find the latest expositions of these .subjects by their colleagues to jjo.s.sess much of interest and value. The arrangement of the Ophthalmological Section differs con.sider- ably from that usually employed: it has been adopted, however, for the puri)ose of bringing the reader into immediate clinical relation- .ship with the i)atient. without confusing him with the formuh-e of optics until the necessity of comprehending them arises in the fur- ther unfolding of the subject. The chapter on the Eye in its RelatUm ■■ VI I'liKFME. to General ^/.srrrsr. w vory (•(.inpri-hciisive. an,| it is lH.|>ed tliat it will r.r.)v<> .,f f.sp..,.iMl value t.> the Roneral practitioner ii, acquaint- inKlani with tho , .Hilar lesions of every jjeneral and I,,,.;,! a. ec-tion exhihitini; sudi manifestations. In the sertion on the Throat, Xose, an.! I-ar. the general chai)ters on Pathology, on Instruments, and or Routine Operations were introduced to secim- conciseness without curtailment of the matter necessary for the thorough elucidation of th.- subjects dealt with. LIST OF CONTRinUTORS. ALDKKTON, HEMIY AHXuLD, M.l)., thief of Aural flinic arj AsHi.«tanl M llir (hair ..f Otolojfv in the Long Island Modical CoUrn.-; Aural .Surgr.m to th.- Urooklvn Eye and Ear Hospital; Aural .Surgeon to the Kings County Hospital and to the Bushwick Hoh- pital; Attending Surgeon to the Ear, Xose, and Throat Department of the Nassau Couniy Hospital; Meniher of the American Otological Society; of the New York ((tologieal Society- of tiie American LarvngoloRical, Uhuiologieal, and Otological Society; of the Associated Physicians of Long Island; of the Medical Society of Gn-ater New York: of the Kings County Society atid Association, of the Long Island Medical Society; of the Brooklyn Medical Society; Chairman of the .Section on Laryngology, I{hinol.)gy, and Otology, Kings County .Me.lical ,Society; Attending I'hvs'i- cian for I)iseas<.s of the Ear, Xose. and Throat to the Home for friendless Women and Children. BIUKKTT, H. S.. Ml).. Professor of lihinolog> and Laryngology in the McGill T nnersity. Moi.ireai Khinologist and LaryngoloRi..*t to the l{oyal A'ictoria Hom-' ,1. Montrea;. F'ellow of the American Laryiigologi, al A-M.eiation. CASSELBEUHY, \V. E., M.l)., Profcsor of Laryngology and Pl.inology in the Northwestern Iniversitv Medical School; Laryngologist and Uhinologisi to the Si. I uke's and Wesley Hospiials, Chicago, 111.; FelUv of the .American Larvngologica I Association, etc. CHE.VTLE, AUTHITR h., F.R.C.S. Exo., Assistant .\ural Surgeon to the King's College Hospital. London; Surgeon to th<' lioyal Ear Ho.spital, London. CLARK. C. I., Mil, Professor of Ophthalmology and Otology in the Starling Medical College; Attending Eye and Ear Surgeon to the St. Francis Hospital, and Con- sulting Surgeon to the Children's Hospital, Colunihu.s, Ohio. COLLINS, E. T1{EACHE1{. F.H.C.S. Eve, Surgeon to the Royal London Ophthalmic Hospital (M.iorfields); Ophthalmic Surgeon to the Charing Cro.ss Ho.spital, and Lectun'r on Ophthalmology at the Medical School. (vii) VIII l.l\r iiF inSTIiinrrnHs (.IlnrKKI I. K. \.. MM, Vi»i»taiil 111 Ori.li.uy ill ill.' Hiii'Minl I iiiM-rsity MrWniil ^.Iiih.I, .\«.si»i;iiii SiirKcoii til thr Ma«wirlinwil« Kyc unit Kiir Intirin,. , ; \ iiitiii)f Aural ''iirisiuii til till' IiiluMl>' .iiiij Niniiiii Mnipiliil-, l»ii»tiiii, Mii!«>, DI \.\K, \I.i:.\ WhKlf Mil. IiiMiniilor ill (•iililliiiliiiiilui.'v iiikI Siirniiiii in ihi- Ilin|Hii»urv <>f ihf tnriii-ll Mfili. al Ci.ll.tfr. Nrw Vork: ^iukioh In ill. niilitlmliiiic ami Aural liij.ti- Hilc: < )|i|itliuliiiiil(i)fist to till- Saiii.iritaii lliiiiic: ^ iMitiiiK 0|)ht>iuliiiiilogii>t ti. the Italiilall's Maiiil Hospital. Niw \ciik. Kl I.KI 1, KDWAIfO ( ., Ml). Oplitliuliiiicainl Aural .Siiiifii HI i,i llir St. .lu-n'iili'^ Hospital, llie City Hospital, .iiiil till' Lratli (Irpliaii \<\liiiii, Mciiipliis, Trmi. GIKI(>I!1», H., M.I)., I'rofi'ssor of (»plitlial:iioloi;v ami O|olo(ty in the riiivcrsitv of Nfl ka. Oinalia. Ni'li. (JOOKALK. J. I,., M.n.. Assistant I'livsiiiaii lor hisiaws of ilir Nose ami Throat in tlic Massarlmst'tis • JentTal Hospital anil in tin' Huston Cliildren's Hospital, Hoston, Mass.; Miiiihcr of the Amcriiiin l.aiyiiKiilo)tiraI .Vssociation. HOI'KIN.s;, F. E., M.l).. I.arynKolonist ami Otologist to llir SpriiiKti.liI Hospital, Sprinnfield. Mass.: Fellow of tlir -New York .Vcadpmy of Mciliiiiir ami of tho Atiicrican l.aryti- polociial Assiiiiiiiion, rir. MAVKll, K.\in.. Ml). MiritiM.ii to till' Nrw 'I'ork Kyi' ami Far Inliiniary (Throat Department); Fellow of the AiiM liiaii I-aryiiKulojfiral A.ssoriatioii; I'hairnian of the Section on I.aiyii)j;iilo(jy of the New Vork Academy of Medicine; Kx- Pre.sidont of the Section on I.aryiiKoloay and t)tolo(fy of the American Medical .\ssociation, etc. NK\V( ')Mli, J. V... M.I).. Instructor in Laryn(rolo)ty in the Coniell Iniversity .Medical (^ollege. New Vork; .VttendiiiK I,aryn){"loKist to the I{oo..«'vell Hospital, Out-patient Department, and to the Deinilt Dispeii.sary, New Vork. Pt)SEV. WII.I.IAM CAMI'HKI.I, M.I)., Professor of Ophthalmology in lh, Philadelphia Polyclinic; .Surgeon to the Wills F;ye Hospital: Ophthalmic Siirceon to the Howard and Kpileptic Hospitals, Philadelphia: .Miiiilier of the .\merican Ophthalmological Society. HKKVK. I{. A., Ml).. I Professor of Ophthalmolo).", mil Otology in the I'niversity of Toronto; Ophthalmic and .\unil Siiiffeon to il .■ fjeneral Hospital and Hospital for Sick riiildr'n, Inroiilo, ( '.inada. IPIRl ItHHMIDSitN, ( M Mil.Ks \\ , M.i». SHI MV • KDW AIM) A , US , M |>.. Opi .liiiolojri^t lo ihi' l'ri'»l,\ ii'iiiiii He ■ .'I'liiisyh Hiiiii: \'(iliiiititrv As^mmm ■ il' (liiiiciil Mriliriiic, I'hiluilflphlH SIMI'soN. WILLIAM KKLLV, M I>. Siirgpon to thf Ni'iv Vmk Ey :,i„\ K.ir Iiil < hicf of ( linic iirul I for Wiilou. ,'iri(l >iii(flc Woiiicii William I'l-piHT L.iliiinitory f'liicf of (linic iiriil Iii..lniiciHii anil Siirifr.iii.., Coliiinhia fiiivrrsiiy, \c-w ^ork : IVIlow of the Amtiri-ni I.aryiiKciloKical A-,. Cliiiii-al I'rofissor of l iphlliaiinoloKy in the Mcliral Drparln. nt of the v.T»ity of UiilTalo; Siiwoii to the Km' and Ear Dt-partiiifnt, Iniv. I)isp<.n«ary. Muffalo, N. V, ; Kye and Kar Siirjjeon . tlii> Erie founty Hosi.ital.CtMin.iii DfacoM.'-s' Hospital, and UtitTalo Hospital of Sis Ini- Tsitv itcru of f'liarity, Hi-ffalo. N. V. sr TEK, willia: ^HWooD, m d. I to the Kpivopal Eyi', Kar, and Throat Hospital, Wash' A«»i«tant Siir it r^f.n. T). » THOMSC' ,, .>■( LAIli, Mil.. K.K.C.S. Kno., As :, . I'hvsi.ian for Disi.nsf.s of the Throat in tho King's College Hospital ; Pi.v ician to the Ihro.it Hospital, (iolden Square; Lecturer on LarvnRoloRy .It the Pnlvclinir; lai.- Surgeon to the Royal Ear Hospital, London; (.or- respondinK' Kellow of the American Laryngological A"sociation; of the Acadenia .Medica of l'lr)rence. and of the ,Socirt# Francaise d'Otologie et de LarynRnlogic : Honorary Liliranan of the Larvngologioal Societv of London. VE.^SEV, CLAHENC K A., A.M.. Mi).. nemnnstrator of Diseases of the Eye in the .hfferson Medical College; A.ssist- ant Ophthalmic Surgeon in the JpfTerson Medical College Hospital; Oph- thalmic Surgeon in the Methodist Kpiscopal Hospital; Consulting Ophthal- mologist in the Philadelphia Lying-in Charity. WEEKS, JOHN E.. M.P., ^r .eon to the Ophthalmic Department of the \ew York Eye and Ear Infirmary; Professor of Clinical Ophthalmology in the University and Hellevue Hospital Medical CoUtg^; Fellow of the New York Academy of Medicine; Member of the American Medical A-isociat ion. x LIST iiF C/JMllllllTOUS. WOOD, CAUSEY A., M.I)., Proffssor iif OplithaliiKiloKy in the Cliicago I'dsl-graduate .Medical .■^choiil; l'rofes->(ir of Clinual (^plitlialiiioUigj- in the University of Illinois; Oph- thalmic SiifRi'iin to the I'assavant Memorial Hospital and to St. Luke's Hospital. Chicaeo; Consulting Ophthalmologist to St. Anthony's Hos- pital, Chicago, III. WHHDK.MA.N.N. H. V., M.I)., Prot'es.sor of Ophthalmology to the .Milwaukee .Medical College, and Chief of Eye Clinic, Ophthalmic and .Kural SurgeKT1NA. i )1>TI(' NKUVK. AND ITS CKliKKl! \l. I5i I'. Hoi.MKs Sri( Kii. !.!'.( .>. Km.. I'AGE OIUC.IN CHAPTKU X. DISKASKS Ol' THK (TtYSTAI.LlNK I.KNS . Hv Ki)« Mil) ('. Ki.i.Kii. Ml). (il.ArCOMA ('hai'ti:h XI. Hv K. rnKvriiKii ('(.i.i.i\~, 1 .l!.( '.>. Km;. CHAITKH Xil. DISIT KinNCKS OK VlSloN WllHOl I .M'l'AliKM I.KSloN H\ Kl.MKH (i. SlMill. M.l>. 417 474 .)24 Otis (MIAITKH XIII. THK KVK IN US liKI.AlToN I" CKNKIiAI. DlSKASKS Hv ('. 1'. Cl.MIK. M.l>. .>s:} ("IIAITKR XI\. (IKNKKAI. IMtKrAKAIToN l( H{ Ol'Kli.VIToNS lI'o.NTHKKVK UM Hi f'f.MiK- ' \. Vk.\>k.y. A.m., M.D. CIIAI'TKU XV. THK TKCHMql K oK IHK HA I Hol.O( IK Al. AND HA(TKI!loI.( •(;!- CAK KWMINVTIONS ol IHK KVK •">' Hv Ki)« Mill .\. SinMWAV. H.S,, M.D. COXTKXrs. xin NOSE AND THROAT. C'HAPTKH XM. THK nisToi.dcrcAr, i'athomkiy of diskasks or thk .\(isk AMJ THUOAT (1S9 MV .1. I,. (looDAI.K. M.l), CHAPTKH X\II. MKTHoDS (ir K.\AMI.\ATI(l\: INSTItlMKNTS AM) AITAUAIT AM) THKIH ISE Mv .1. !■:. Nk VMOMIi. M.I). CIIAPTKK XVIir. IM l..\MM.\T()l{V DISlvVSK-^OI'THK VVVVM AIU I'\SS\(iK-; H \V IKNKI!: I!HIN()HHH(1;A; .\STHM.V. I.MI.r:.:xz A Rv ClIAHLES W. UlCHMIDSON. .M.l). ("HAPTKR XIX. nil'HTHKIil.V Ol .NOSK .\M) THUO.U': I.NTIHATIO •iVl'Hir.b TrMKUCll.o.slS, HITS .VM) LKl>|{().sv OK .\( )SK AM THl!oAT;("HI(oMC l..\l{V\fiEAL STKXOSI.S; KoHKKi.V HOI)IK.> I.N \o.sK A.NI) THito.Vr; liHINol.ITHS . . . . ' IJv Wii.MAM Kki.1.. SnTi'sdx, M.l). 829 ("HAI'TKH XX. NKOIT.A.sMS ol' THK NosK AM) I.AliV.W: THK I.OC.M,. MKDI- Cl.WI.. A.NI) .slTUilCAI, ri!KATMK\T OK THK I..VI{V.\.\ . Mv W. K. Cassk I.IIKHHY. .M.l). (•iiapti:h XXI. l)l.e studieil to better advantage than the eye, for it presents in a compact form representation of nearly all the tissues of the l)ody. and by reason of the transparency of some of its coats the stude I is enabled actually to witness i)hysiolo(rical and patho- iofricai ])ioces,ses occurrinfi within it. A living nerve head, the optic papilla, and the retinal vessels are unfolded to the gaze of the oph- thalmologist, and an opportunity aHorded luiu of ob.serving the perfect cycle of the supply of an organ with arterial, and the escape of its venou-\ blood. For the proi)er study of this important organ it is e.s.>ieiitial that the stu inspection of the eye itself, it is ailvantageous that the general physical condition of the i)atit-nt should be taken account of. For this purpose he should be seat"'" in a chair facing a win- dow, the student, with his back to the 'ight, seating himself several feet di.-itai.r ,' the patient. I'nder this .strong illuir.itiatioii i'-- entire person of the pati etit shou ld be raimlly inspected, and any de|)arture from the noriuaHff^liS^^^Lportions of the skin and of the glandu- GU^|G 20 riir: eye. lar sysiciii. ;is well ;is the cliMiMclcr 111' ;iiiy cniplion, iintcil. Iiiili- catioiis 111' arin'riiia nr ]il('llinia slupiihl he sraiclicd for, ami any t'vidciKM's (if jaiiiiilicc. I'itially. tlii' jrciicral ('\|ircssi((ii uf tlu- palii'iil aiiil tlic prcsciK r alisciicc nf pain, or of any iiitolcraiu-c to lijjlit. slirttilil III' laki'ii into ai'i'oiuit. Inspection of the Eyes and Their Adnexae. 1'liis p>ncral survey of tlic casi' l)i'in<; rotnpli'tcil. the atli'iition of tlic stmlcnt slioiiid he iliri'cti'il niori' rspci-ially lowani llic rrfiion of the eves, 'i'lic sliapi' am! jjcnrral nmlijiuralion of tin' head and the character of tlie wrinkles in tlie skin of the forehead and at the root of the nose should be studied. Any tendency toward laeial asyniinelry siiould Im' noted, ;ini| coinparison made whether l)oih orbits are on the same horizontal plane, and whether their cav- .es arc deep or shallow. Tile dejrree of prominence and the size of tlie eyeballs should be remarked, and the relationship which the eyes bear to one another. MsiM'cially should the |iresence or absence of iiiflarnination of tlio eve- balls be taken into accotmt : if but one eye is diseased, it.s condition should be compared with that of the sound eye, as comparative examinations of this kind are frei|uetitly of irreat value. The student should I'arefully scan the rejrion of the sinuses accessory to the eye, to detect swelling or si<;iis of inflammation in then.. Any sifjiis of jirevious injury about the eyes should be recorded. Tiio attention siiould then be directed particularly to the lids as to any inversion or ('Version of their edf^es, or thickening; or distortion or swelling of them: estimation should lie made of abnormal narrowness or width of the lialp<'bral fissures. The action of the orbicularis: in closinji the lids should be tested, and any twitchini,' of the lids and .-issociated muscles ol the face noted. The rejiion of the iimer canthus should be in- spected for evidences of swellinsr. or retained tears, or other sipis of faulty drainajce in the lacrymal apparatus. Havin-i ol).-;erved the ccu|)ation, certain callings, !)y reason cf the accidents to which they expo.se the eyes. ;inil others, by the enforced strain which they pl.'ice upon them, bein-; particularly li.ible to produce ocular lesions. Inquiry should also be m;ide into the inarit.il relations: and if the patient be married, of the mimber .•md health of any ofl'spriiij;. Any hereditary ten- dency, particularly to ocular disease in the .•incest ry, should "be re- corded, also the temperament of the p:itient, w ' 'ther it be saiiftuine or the contrary, in order to ascertain the value a\u\ deirree of reliance to place upon the patient's statenients ri'<,';tiditisiii;; tlicir sensations. The lial>its slmulil he iii(|iiiro(l into, espe- .-ially rejianlin;; I lie use of alcoliol and tobacco. If .s\|)liilis lie suspected, (|iiestioii should !)(• made rej;ardin>: the primary sore, a.-^ as the tune ot appearand' i if anv s<'condarv manit'estatinn: .Ml previous illnesses should he taken account of, especially of the exist- ence ol j;()ut, rlieumatism, tuberculosis, malaria or other dyscrasia. The urine should he tested in ;dl douhtful cases, and its examiiuitioii made a part of the routine in all ca.ses rec|uirin}; important o|>erations upon the eyehall, such as cataract. If the jiatient he a female, she should he (|Ui'stiotied rejiardinj; menstrual disorders, and particularly as to the iiilluence of the menstrual epocli ujioii the ocular symptoms. I'inally. should the inspection of the patient have aroused suspicion as to invoh nient of the central nervous system, in(|uii>- should lie maile of all ,.ossihle .sensory and motor hody Ix-iiiji supported ui>oii the lap of all atteiidaiil. who should also grasp the hands, the lefis heiiij: left free. The head heiiif; thus rendered iin- niobile, the surfteoii can inspect the iiei«hhorinK [larts delilx'rately, and cm examine the eye satisfactorily by drawinn the lids slowly apjirt, hy piessiii); on the inferior and suiM-rior orbital ridges, or by inserting a Desmarres lid elevator (Fig. 1) IxMieath them, always exer- 1 Flu. 1. 8= IXiiniarres' Ud retractor. cising the greatest care to avoid pressure u|)<)n the "veball itself, for fear of injuring the cornea. When there is marked intolerance to light, a 4 |M'r cent, solution of muriate of cocaine may often l)e success- fully employed to allay irritation, although in some ca.ses general atuesthetizatioii by chlorofonn may have to be resorted to before a satisfactory examination can be made. In adults it is possible to examine even the most .sensitive eyes by making gentle traction on the lids, by drawing them toward the inferior and sujK'rior orbital ridges, thereby avoiding pressure upon the eyeball itself. The Lids, the character of any changes which have been noted in the lids during the general inspection should now be studied more carefully, especial care being devoted to the condition of their mar- gins, as to misplaced cilia or the presence of i)edicuhe, and the char- acter of any incrustation or swellings. Lacrymai Apparatus. The region of the iimer canthus should be in.spected most rigorously, any locali.Tcd injectiim of the conjunctiva or collection of tears or mucus at that point exciting the suspicion of obstruction in 'he |)roi>ef canaliza'ion of tli<' secretion from the eye. The iiosition an 1 patulency of th(> lacrymai jnmcta sliould be a.scer- tained, and gen 1(> ])ressure made with the ti]) of the finger over the lacrymiil sac, with a view to expressing any retained contents. The Orbit and the Position of the Eyeball in It. I'neiiual |)rominence of the globes may be measureil by placing the straight edge of a card from the supra-orbital ridge to the cheek, and comparing the distance of the cornea from the card on the two sides. Palpation of the orbit should be practi.sed by passing the index finger along the bony margins of the orbit, the finger being allowed to dwell par- ticularly over the region of the lacrymai gland, to detect any enlarge- ment or uneveime.ss. Pressure ov(>r the foramina of exit of the rupra-orbita! air! infra-orbital nerves should not \n-- nmitted. The Conjunctiva and Its Cul-de-sacs. Before exploring the recesses of the cul-.\ Of run EYK. %\ ntluis sliiililil Iw cXiitnilH'i llic IIIIH-r CM liiiilirs. The ciiiijillictivii I for sniiill growths or foroiRii if tlic lids, iMil/H'tinil ninjiiiirlini, slioulil tlii'ii !"• iiisiM'clfMl, Mini Miiy I'liMiiKi' ill its vasci ilaritv or in the fliariu'tcr of it- nittci timi. ami lln' prt'sciii-f of crai ulatiiuis or forcijtii liodics, I. T (Ml ) fxaiiiiiK- tlir coiijuiictiva <>f ll"' rvtrotarsal jnlds aiul the •ccssary to t'ViTt the liiis; tiiin Is n-Milily aci-oiii- f the lower ciii^ It-sac l)y tirawiiin the lower liil Inle-sacs, ll IS 111 IiII-IkmI ill till- i-ase ( . , , -, i mnllv.lowii with the index hiijier of the rinht hand, while the patient w told to direct his pi/.e upward. Ins|)<'ctioii of lh<" U|)|mt cul-de-sac w lesx simple, and is iwrfori 1 hy uraspiiijj the edRe ol th.e upjM'r lid .,nd H few cilia with the thuiiil. and index tinker oi the rijilit hand aiH 1 l.v deluessiiiK the ilp|M'r edge of the cartilajte o tiiip'i a i>ro f the lid with a ..f'tl'ie left hand, o'r'with .-".me convenient instrument, such as \U'. while the patient looks steailily downwar.l. IK n'(|U('stinK the i>atient to 'lirect his gazt till further downward the pal|M'hral iiortion o if the lacrvinal jrlaiid may he brought into view. The Uulhitr awiinirlirn is on liiiarilv invisible save for the few bloodvessels which are .list libut.'d throunii it. The color of the sublying sch-ra sliou i„. noteil, and any uiuliie vascularity ami prominences taKcr ''"iVfl'iii'proceedinjj further, it is desiral.i.' that the stmh-nt should have a clear idea of ''le vas(Milar supply of the exterior ot the eye, in <.rder that he niav ajipn-ciate the ditTerent forms ot congestion lH.(Miliar to the vessels of the several tissues, as no other synii)toiii .'ives -iuiir indication of the location of ocular lesions. " Bloodvessels of the Exterior of the Eye. The vascular supi.ly of the e\i(ii.>rof the eve mav b.' grouiK'd for convenienc- into three rforatii.^ arteries supply the sclerotic, ins aiul ciliarv bodv, th.'ir veins receiving the blood ironi the canal ot Schlemm and the ciliai •V bodv. Tl ies(> vess( ■Is are visible in health as .several iiiiparatively large tortuous vessc Is which perforate the globe about .) mill ve "tlie'corneal limbus. The non-iH-rforating or epi.sdtMal U which are branches from the anterior filiary vessels, are very lil th heir )f closely set ves-els around the cornea. ,, ;i. The Aiiterinr Coiijiiuctirnl Vessels /."»/;. -p/cj/'/'v on" tile' Corneal Border. The.se are the ves.sels ml immediatelv adjacent zone iiiimeious Mild lorm a zone o Thi'V are invisible in health proper to the margin of the cornea a if coniunctiva. and it is by means ( f these numerous minute branches w hicl 1 iire o itTshoots of the anterior ciliary vess( •Is tliat svstoms 1 and J Mllastomo.se (Plate I.. Fig. 1.) Conjunct" 1 congestion is the nan given to indicate that f' :i ■ s cohgestioll \\ lich is caused bv .an injection of the j.ostorii •tiv; ' vessels. The inie( junc its imiii.'i tioii is most markeil at the for: \ .'in iiat e liel 'hboih d. where these vessels are iiu; and is less noticeable aroum id the cornea. The vessels being ? 24 TIIK EYE. tl 111 till' con arc e ijunct iva, iiiav 1)0 made to slide readily over the filohe, and iisily emptied hy pressiiiji on the lid with llie tiiifjer. I:i thi form oieoiifiestioii the eoiijunetiva assiimi a v< 'llow or hriek-red hue specially in the re^rioii ot the inner eai thus, and there is more or le lUicopurulent dischaifii Coniunetival eoiij;estioii is diajjiiostie of eonjui tivitis. (IMatel.. Fif^. -'.) CUary or circumcomeal congestion is the name given to an in.i<-( ^ •' ... 1 : ,.l,..t;ion assumes cim.-i n ,.....x..-,. ... .. • - rsi; ,r,- cases drHM.-s..at.'d patches of a lilac or violaceous color ai^i-ear ( iharv i„j,,,,i„„'i„.lica.cs disea.s.. in the cornea, ins, or cihary '"'Iv- ^vlie.i ,1,. p,.,.,.liar liia.-colore.l patclies are present, disease ot the dcper Ivini: tissues, the s.^lera, and ciliary body is indicated; and when observe.! in connecti..n with enlarpMuent of the episcleral veins, a chronic hicrease of intra-ocular teiision-filiuicoma— may be sus- pected. (Plate I., l-ifi. :].) . , f , . ;. Mixed Forms of Congestion. On account ot the free anastomosis „f the three f;roU!)s of ves.sels, it frequ.M.tly hapiH'iis that tiiere is in.-nrinfi „f the different types of congestion into one anot i.'r It shouMbe borne in mind, how, .T, that while a prolonged cihary ,..,n.r,.,tion -raduallv producs more or less conjunct iv.d congestion, th,."converse is not 'true, for a conjunctivitis will not excit." a ciliary injection unless the cornea or iris also is aflected. The Cornea. Tlie shap.", tlu- -eneral curvature of th<. cornea, and the .position, extent, and d..nsity of all invfiularities and opacities in it sli.H.M be stu.lied on account of the imp.)rtant bearing which tiiey have upon the vision and n.fraction of the eye. lor tins purjiose two UM'thods are available: examination of the corneal ivll-'x and direct inspection. , ,• , f Examination of the Corneal Reflex. Wlien the lifihl from a win- dow i~ pennitted to fall .lirectly uix.n the cornea and the eyes are „,.„!,. ,,, follow th<' hnger of the surgeon while it is tnoved ni various directions, it will !.<• noticed, if there be any irrefiulanty „,„,„ ,1„. .utiace of the c<,rnea, that the imafje ol the vyindow Ini- wluch is thrown upon it, inst<'ad of beiiifi reflected clear and well defined, will be broken and ill defined at these ponits. The same principle is made us.' of in th.' api.li.-ati.m .)f the I lacido disk iV\» 2) This con.sists of a tarjiet nu which are coii- .vntri.' allernat,' lilack an.l whit.' circl.'s. with a cntral p.'rlor:iti..ii In its emplovm.'nt. the pati.-nl should b.' place.l with Ins back :,. ,!.,. li.ri.t "tlie ^utw'on viewimr the ivflectum .)! the inuiiie ot •1„. einles np..n th.' corn.'a through th.' op.'niiifi in the c.'iitre ot the ,>'sk. .\nv irr.'}:ularitv .)r .'xcssive ditlereiicL' in the curvature -••ir.^-'T^-'" L i:xAMry.iri(>y of the eye. 25 n.TicHans ..f the conica will ho inaiiif.'ste.l hy a break ..r .li^- „,,,,„„ i„ tiw cirdes. Th.> cor,m,l rejkx should always ho studio.l 111 till' ini PlacMo's disk, or keratoscope. .,. pail of tho loutii.o ..phthalinoscoinc oxaniinatioii, the ohscrvcr M.linnin!: hiinsolf for this purpose hehiu.l a...l to one •'^•'li; <''<"; p:,ti..nrs hea.l. so as to have the patient s face ni shadow. The light Fio. 3. Corneal Utuiie. IS then thrown upon the eve hv a i-laiie mirror, and llu- shadows care- fnllv studied through a hole in the mirror. iVuie lietmoscopy.) 5 I ^ Tllh: EYE. ■n„. ,„„, n.c;,.,o .,.1 ,..].».«- ;i::j;;',i,:':ri>™,;:;;;:!'X „f th.' vnvnrix l)v iitilizms: tlu" ivilrx tli.tl it (ax. opi.thaiMx.uiotcr. ( r*wr pafi'- n^) , ^^-.^^ „„, „;,u..,l Jackson's liiiuiiular inannitler. ;i;'r:::a;'r:;::*n;i:i::«:.;;»y i. us,.,u,„,.i, ,.,i«.n spt'cially coi.j^truct.Ml for tliis purpose. Fio. J. OMiiiiie or focal illumination. tnra! }!ln>.>i'il>IH>: iscul 10 cucnural. llic light upon llio cunu'u. ^^h^\v the (.tlu.r .. t used lo couci i KXAMiyATIOX OF THE EYE. (>iii]ilt>yf( [IS a i»:i cnifii'i thiDudi which tlic ilhiiiiinatfd surface ma\ lie -liichi't with t 1. iKifl. 5.) riic iwticut slioiild l)c seated in a lark rooiii lie lijrlit on t^.e teiiii.-)nil side and siifjlitly in front of tlie phUK Tliis method is extremely vahiahle, for l)y vary i| tiie patient's tac'i lis: the distance! 1 (•iian':<-s in illal i tlie lens from tiieeye it is possi ilile tosti.dvnotonly tlie cornea, Imt also tliose in the anterior chamWer, iris, and an( I if tlie pupil l)edila ted and the lifjlit thrown almost peri)onilic Iv into tiie eye, chaiifies ii 1 the anterior layers of tlie vitreous iiiav be niai le out as \v( ■11. I.IIS.< llj SllhsldlICi in the viirnvdi vpitlivliiDti ma V be demonstrated by instillinfi a drop of tluorescin in cent.: carbonate of sodium, ;}.5 per c( to the eve ((iruebler's tluorescin, 2 per ■lit.), the surface frosn which thf rpithelimn \vliil<^ the n is removed being stainei 1 pre* •111 isli vellow bv the drug. St of the membrane remains cU The iitiir)if--f of the cornea \ tested best by gently touching it with a wis]) of cotton if sensation be unimpaired, the eye will wink ri •Hexlv: but if the lids remain iinmt ibile, further investigation of the sensibihtv o ,f the skin of the surroundnig tissue should Ik> tnade with an a he.siometer, to determine the extent of tlie aiuesthesia The anterior chamber Should be examined in respect to its depth and contents: among iiig the latter w hicli the chamber may contain being ,|„„d, or hjiphnnw: pus, or huropijon. and foreign In bodie; The Iris. In the exaii nil iition of the iris the attention should be lirected chiefly to its color, to the appearance ( if its stroma, and espe- cia iris llv to the size, position an< 1 behavior of the pupil. The color of the du( to tl le auK )uiit and distribution of the pigment in it: m ;ilblllisni. w here there is an absence ( )f pigi lien t. the iris is translucent, 'I'***'*/ p^^ ton* Tlieirisi. (Kiths.i Miwi ill iiewlv born children it is almost invariably of a ligiit grayish _ blue The "irides iiiav ditTer hi color in the two eyes, chmmalic asiiw- m m>'lr>r or iiarts of tli'e same iris may be colored ditTerently, piebnld m u;>. Discolorati.m of th<> iris .sliould always .-xcite suspiciui. <,t inllalliliiatioll of melilbriilie. :sw«HK-'£ ■'^if^syfi-mss^-^t^mmmmtsmjnijmDs-j, IP 28 THE EYE. Wlicii vicwcil ilirniijili a iiiaiiiiityiii;: ass. witli tlic aid of ()l)li(iuo illiuiiinatioii, llic iiis is seen to I ic (Miinposci )l' a sciics ot elevations (Fiji. t>) ;""' ilepressioii vessels, wliicli run rat while the deijicssions cor s, the foiiner ix'infi occasioned by the hlood- liaily Irom the base of the iris to the pupil: res"|iond to cryiits in the stroma of the iris. and are found chietlv near the pn|)iilary luargni. Although these elevations and depressions are sharj) and distuict in the normal eye. they become blended in intlannnation, which constitutes an important sijin of iritis. Ciianfies in the i)iane of tiie iris, tears in its i)upillary edge and base, and any wavedike movements on its .surface, /r/V/<«/('/(c.s/.v, should be .searclH'd for carefully. Thickening; and vascularity of the membrane .should be remarked ami the character of any nodulation noted. ThePupU. The chief characteristics of the healthy pupil are it.s circular outline and its mobility. The size of the i)ui)il varies fjreatly in health, ranging from 2.44 to .').,S-_' millimetres, \m\\^ intlueiiced by age a: ! refraction, and is directly dependen, upon the stimulation of the lighi. acconunodation and coii- verfient imp\ilses which it receives. \Voir',!\v places the average at 4.14 millimetres. As a rule, age causes the pupil to grow smaller, and it is also more likely to be smaller in hypermetropia than in myopia. Its width mav be 'a.scertaineferably of glass, graduatcnl in circles ranging from 1 to S millimetres. (Fig. 7.) This is held close to the eye, and wliile 1 Fir,. 7. nirschbvrn's piiplllometer. the patient fixes his gaze upon some distant object, the circle should Ix' found which corresjionds with the diameter of the pupil. I'ntil the student has ac(iuired suflicieiit skill to enable him to obtain tin accurate measurement of the pupil by simple inspection, some such scale slxiuld be employed in ail {'ases. The pupil should be" nnnxl, but this is usually prevented bv astig- matism, which gives it an oval a|ipear;mce: it should also be situated sliirhtlv to the nasal sid(> of the centre of the cornea. The sejiaration of the jnipils from each other varies with ag(> and sex ;iiid with the form of the face: i" .adults it has an nvi ol 58 mm., although Nagel places it at i\.\ nun. fXAMISATIoy or THE EYE. 29 Till' pupil is rarely dear hhu-k, the antorii)r surface of the lens re- lli(tiii<; some lifjht; iiuieed, tins reflex is often so marked in elderly siilijcct.s that the grayish film due to sclerosis of the lens is often mis- taken for cataract l)y the inex()erienee the hloo.lvessels of the iris, < traction of these vessels causinfi narrowiiifi .if the iris aiul dilatation of the pujiil. The reaction of the pupil is eith.'; irjlcv action, in which event the impulse passes al.irifi the o|)tic nerve, the afferent nerve, to the oculo- mot.ir centre, ami aloiifi th 'uLimotor nerve, the afferent nerve to the eye. throuf;h the me.lium of tihres which connect the cor]»ora <|Ua.l- ri"eniina with the nuclei i>f the oculomotor nerve; or it may l)e ((.-«>- n7iliil, in whii-h case the imjiulses arc set into action sinuiltaneously with etlorts at accomin.i.lati.m an.l converfience. The .lejiree of the puiiillarv contraction in associateil action is always less thasi that ohserveil in the reflex reaction. TiiK iii:i-i.i:x 1{KACTI()\ of the juipil may he either dinrl or nmscn- siKil. The ih'ircl Hijlil n'jh-x is the extraction of tiie juipil which is ohserveil in the eve when it is exi).ise.l to increa.se.l illumination, the (■Diisfiisiiiil or itiilircrl liiilit rcjlrx beinji that which occurs in the pupil of the other eye, foll.iwiii}; e\i)osure of one ey(! to lifjht. The direct ' li'ilit rvjler is hxtcd hy alternately shadinji an.l un- c.)verinfi the eye in daylif;ht with the iiand, or hy concentratiiifr artificial li};ht upon it, either hy means of ..hli.pie illumiiiati.m or t\v the mirror of an ophthalmoscope, the fjaxe of tlie patient iieinj; iixed on a .li>tant .ihic-t. to avoiil any associated stinuilus from < ither accommodation or converjience stimuli. It sometimes haiipens that after the cover is removed from the eye the hrst contract i.m of the jMipil to light is followed hy dihitation. and often an interval of extreme contraction, heing succee.led l)y mo.h'fate dilatations and contractions until the iMi)il hec.imes stationary. This condition is terme.l liippm^. an.l is cxplaine.l hy Swanzy .'is follows; V.wh con- traction .if the pu|>il, hy .liminishiiif; the sujiply of light to the retina, contains in itself the cause .if the succee.ling .lilatati.m ; an.l for the c.inverse rea.son, each dilatati.in sots ag.>ing the succeeiling coii- triu'tion, imtil at last e.|uilihrium is attaine.l. llip)ius is seen in cerehro-spinal sclerosis, ilisseminated scler.isis, neur.isthenia. hysteria, psychical .listurhanc.'s. ejiilep.sy. an.l acute meningitis in its e;irly stages. The conscnspdl or indinrl jiiqiillar;/ nadion i." Ii'slcd hy .iliserv- ing the motions of tiio pupil in the other eye while the eye under examination is heing alternately covere.l and unc.ivere.l. This test is ilepen.ient anat.iiiiically u|)on the fact that fihres pass from the retina .if each ev(> thr.iugh tiie chiasm partly int.i the right .an.l partly int. I the lelt optic tract, an.l th.'it t'r.im these the stimulus is trans- mitte.l ilirectly to h.ith right an.l left ocul.imotor nuclei, each micleus setting up a contraction .if the pupil of its own si.le. t:xAMiyATwy of the eye. :J1 Tlic (lircM-t light reflex is tested for tlie purjjose of detectiiiii the cxisleiice of adhesions of the iris to the capsule of the lens (posterior synechia), and to deteiinine the sensitiveness of the retina and of the visual apparatus ftenerally to lifiht. The reaction is an exceedingly delicate one, and indicates the presence or ahsence of (|uatititative perception to lijiht. It will presently he e.\])iain(>d, however, that the iailer function may he wantitif; in certain diseased states, and yet the pu|iil reflex take place; or the pupil reflex may he wanting, and [xt- ccplion of lifiht still be present. Tlif (issocifitt'd rciidion aj the pupil, or the (i(rn and ruiinr- iltiicf irjh.r. is tested hy ro(|uestin}i the ]>atient to look fixedly at an nlijcci iield in t.ie median line about 10 cm. in front of the face. The ccntraction of the pupil which follows is due to the intimate associa- tion of the central innervation of tite sphiticter nuiscle of the iris, the ciliary i)ody, and th>' internal rectus muscles. While accommodation unassiiciited with converfience will not cause contraction of the pupil, reaction follows converfience stimuli alone. In contradistinction to the contraction of the pupil when acted upon by lii;ht or accommodation or conver<;ence stiir '" the pupd inmri- tililif ilildtes irlien itrted iipi>n lii/ seuyori/ ytinndi. 'l.hs the ])U[)il which is contracted diu'inK sleep and deej) narcosis dilates at the moment of \vakinis (i| the dil.iting hbres of the jnipil or of the pupil-dilating centre a moderate contraction of the pupil; if both are active, the 32 TIIJ-: i:yi:. I'lipil IS (•(iiitiactcd to a |)iiii)<)iiil. ('out raft ii.n df tlic pupil follows :""»i''':'^' i'"* Klimulution of both dilatiiij; aiM coin met iiij; mccliaii- isiiis. The most comiiion cause of coiitractcii pupil in disease of the eye is aillierence of the iris to the lens capsule. Sjuislic „ni„si.y is syinptoinatic of intlanunatorv alTections of the i)rauiand its ineniii>,'es: it is present in the earlv st:i«i-s of intracranial tumors which involve the third nerve; it is se'en at the bcfiimiiiiji ,,f hysterical and epileptic seizures. I're.ssure upon the pons cau.ses myosis. It results from stimulation of the pupillary contracting centre, and occurs in those who sutler from tobacco amblyoiiia and In those who follow trades which demand lon<; maintained" efforts of accmimodation (wat( hmakers, jewelers, etc.). If, in the course of a case of cerebral .li.sea.se, myosis jjives wav ti> sudden dilatation, the im.RiK.sis becomes uravo, the stapc of depression with paralysis of the third nerve beiiifr indicated. .Myosis may be a rcHe.x action in ciliary neurosis: it accoinpaiiii's m;mv disea.sed conditions of the por- tion ot the eye supplied by the fifth nerve. The pupil in irritation myosis IS but htlle affected by reflex stimuli; it is verv su.sceptible however, to drufts. mydriatics dilatin^r it widelv.and mvotics c(.ntrac- tiiifi It ml mnximum. In contradistinction to" this, the pupil in par- alytic niyo.sis reacts actively to the ditTerent reflex stimuli, ami is but little afiected by mydriatics, althoiifjh myotics contract it greatly. Pariilnlir mi/osis occurs in spin.al lesions above th(> dorsal vertelme and IS especially sif;nificant of tabes dorsalis. In the earlv stages of this di.sease, in which the cilio-spinal centre or the hijiher n'-gion of the cord alone have been atfected. the pupil is but moderatelv contracted, and reacts to both lijjht and on convergence: later on, th" pupi! I>reseiits the phei leiia which have ben characterizeil as inii/ll- Rohnlson i„ipU or /-cy/cr iri(lo,,la,i„~i. v., the pupil responds verv .-liKhtly or not at all to lifzht, but is .active in accommodation and conversreiice. The lesi„n which produces the .Vrfjvll-Hobertson pupil has been variously situated in the fibres which pa.ss from the proxi- mal enis of the insane. In this latter disease the myilriasis is fre- i|iiriilly unilateral ami is assoeiateil with inyosis in tiie other eye. In spastic mydriasis the pupil is motlerately dilated, contracts >lii:liliy to li;;ht and converjience, and does not dilate to sensory -liiiiuli. .Mydriatics dilate the pupil f the nucleus of tiiis nerve in the pons, or truin failure of the stin Jus to be conducted from tlie retina to that ciiitre. The pupil is n derately dilated, reacting to sensory stiiuuli and to li<;ht and on converg'-nce, accordiiiR to the seat of the lesion. Thus if the lesion be between the iris and the pupil-contracting centre, tlirrc is no reaction, eitlier direct or consensual: but if the lesion lie Ik I ween the retina and the pupil-contracting centre, the pupil will ncit contract directly to light, although it will consensujilly and on convergence. Mydriatics dilate the pupil ad timxinnim, but myotics <'ontiact it but moderately. I'aralytic mydriasis occurs in diseased |)roces,ses at tiie l)aso of the br.ain, involving the centre of the third nerve: in affections of the orbit which exert ])ressure on the ciliary nerves: in cerebral processes attended with mark(>d increase in the i)re.ssure within the skull, such a> tumors, hemorrhages, and absces.ses, and in the advanced stages of thrombosis of the cavernous sinus; in i)rogressive paralysis: the later stages of meningo-<'ncephali1is, and acute dementia. .Macewen i- authority for the statement that hemorrhage into the centrinn o\ale and cerebral ])eduncles also produces mydriasis. (llililli(thii<>iil('(/i(t intcriiii is the name given to tlie dilatation or |iaiti,il dilatation of the pupil associated with a failure to contract iHKlcr stimulus: loss of accommodation accompanies it. The condi- liiiii indicates a nuclear lesion. Transicnl mudn'asis affecting first iiiic eye and then the other, is generally regarded as prodromal of iii-:inity. It may be stateil as a general rule, that dilatation of the pu])il wliin observed in connection with a cerebral lesion indicates an ex- irii>ive lesion of th(> brain; ind, when it is of spinal origin, irrita- tion lit the part affected. Mydriasis is conunonly observed in glau- I'liiiKi. When mydriasis is due to a failure in transmi.ssion of the liirli! -linmlus to the pupil-contracting centre ami nerves, |)upillary aiii\iiy occurs only on convergence. The mydriasis which accom- panies ijptic .'(trophy is the type of this class. Till' dilatation of the pu])il which is observed in complete blindness "iiiiinirosis) should not be considered as a disorder in tlie mobility of 3 mmmim 34 THE EYE. tlio iris, hut should rather 1m' n-pmlod as a physioloKicitl inhibition of th(> impillary n-flcx .liic to th«' witlidrawal of tiic iM-nrption ot heht. The Iwitii'iinoiiic piiiiilliirn innctiim sit/n (Wtrnirkr's). Hv a of tl.ix sipi it is somctiiiK's possible to di-tcriniiH' ii' (vrtaiii cast's of half-bliiidiicss whctluT tin- s.-at of the lesion is situ:;ted anterior or posterior to the (•oii«>ra .|im.lriKeiniim. (Fiji. 0.) This t»^t de|K>iids upon the fact ihat the visual fibn-s in the optic nerve join the hbr^s of the third nerve, which contro' th:- sphincter pupilhe at the corpora (luadrineniina. If the lesion Ix- iM)sterior to this point of junction— i. e., ■ back of the coriM'ra, in tlu' oc"ii)ital rortex-there will !«> no inter- ference with the i)upillarv n-Hex. Should, however, the lesion Im» situated anterior to the eorpora, the reflex arc of pupillary activity will he broken, and an irregularity in the pupillary contraction wil manifest itself. The hemianopic pupillary inaction test is jH-rforined Ix-st bv placing the patient in a 1.U and line [«».inK through centre of eye t,. M. 70° and iifi. rays of light striking the iaseciUve nasal half of the retina, proriucing no pupilUry retlex. (Skuuin.I illumination back of him, *he eye not under examination being closely baiiilaged and the patient being directed to lon it bv a plane mirror, while the examiner turns a narrow beam of light, reflecteil from the concave mirror of his oiihthalmo.seope, upon the different parts of the retina, and closely observes the effect upon the movements of the iris. The cerebral cortex rejhx of the pupil, or Hmth's rejlex, is the con- traction of the pupils in both eves which occurs without change of aeoomiuodatioti or rt.iivergf nee when the sv ieet, seated in a dark room directs his attention to some Imght object within his fielil of mF^m. wm wf^m. KXAMfy.lTlnS OF THE EYE. .•»6 vision, the amount of fontructioii Ikmiir proiM)rtionat(' to tlic luiiilit- riCSS of till" ot)j<'ct. Tlif (irhinihtris piipiUarij mirtiini, wliich is used to lietcriiiiiic a |i..ssiiiic paralysis of tlic sphincter of the pupil, is a coiitractioii of tiic pupil wliirh occurs u|)on forcci I closure of the lids. Clifford, the discdViTir of this reaction, Wieves this contraction to he an over- He iw stiiiuilus which is excited in the nuclei of the orbicularis hhres of the facial nerve, anil conv yed thence to the pupil-coiitractinjj centre. It is Ix-lieved that when trigeminal anasthesia is associated with rellex i)upillaiy innnolnlity it may 1m' a.scrilM'd to a lesion of the spinal root of the fifth nerve. I'lirtuliixivnl piipillnni reovtion refers to the condition said to he observed at times in meningitis, when the pupil dilates U!K)n exposure to lifrht, and contracts upon its withdrawal. The Light Sense. In order to test the power jK)S.ses.sp(l by the retina and the visual centre of appreciating variations in the int«'n- sitv of the source of illumination, an instrument is em|>loyed which Phciiometer of Kiireter. (FucHSi is known as a photometer. (Fip. 10.) This consists of a square box in whii'li are placed black lines ecjual to certain standard letters when seen at one-third of a me' -• from the eye. These lines are illuniinated by a standard candle, tl; degree of light l)eing regulated by a window, the size of which may be varied. The patient is first made to look into the apparatus with the window closed. The window is then slowly opened and the lines illuminated. As socm as the lines are recog- nized the size of the opening re(iuisite for this jnirpose is noted, anil if it !«■ found that -m oiM-ning more than 2 mm. sciuare has been re•(•, Willi"' :i ^"•••"li'l <•;> UK III' is J'lWi rifMnf\isi..ll.i Ilnldrn'stl'st for tins ,„„.,,ns....-uiisi.tTin':;Mvrtaiimif: tli.- ,H,ii,ts uii tli. I«'«i"";'<''; •>' wllirli Wl.ini :i >.'Vi..s nf t. st >^rr^. i~ |K.nvlV... . Vn drU.-l .IptUll-all. I . ntrnu,.,liMt.. an.l .-iiliiil /uii..s ..f ti..- h.'l.l. Ii. .Miiplnys a ran , " „„, ,,,,..U ,„.i,i, -11 ....... A.U' a.ul a 15 iiini. ;,ua,lia.i ut M.t ) . li.vin,' luui-litths nf tlii.int.-nsity ..f tlu; wlut... on tlu- o lu • \\ iii ■rim,..,.r ul' :;() .■in. ra-lius tli. Mark point and «ray ,>^. .•!. a.o .; .. , l.v .1... noniial ..y.: oiilwanl »:. .I.%mv- upward .« d.-j:n-.- , ■ rd r. d<■"••'•<•^ downwanl :;:. d.^-nvs. To drt-'t jM-npluTal di- Jid'; lid a' dark..,- «.ay pa..!, having ">'--"' "-.""• "":i";;;,;i^ vvliit- on ,1,.. otliiT. i:a.-li >l.oi.ld i... s..,.n on tl„. I7-'"'''''''^ ' /'l: l.nvin^r pnints: ,.„tward 70 d.-n-.-s, upward l.> d.rn-.'s. mwa.d ■>.. ilc.Mvis, and ilowiiward .V)dcs;nMS. ; . i:.,hl.. uf tension or intra-onilar rcsistam-c i> liaiiic Tension. As tiii'dc^ivi 111 vary in many discascil taiiH'd ill every case. eonditions. it is es.sential tiiat tins he ascer- Cliiiieallv it is not jioss sihie to a.s('ertain direetly the intra-oeiilar Uiiiieaiiv II 1^ I"" i".^.-..- - f . , „vs>u,v 1 lit a sulliei.nllv aecurate estimate may he made of it l.> '"i. n^' t!ie tension of the eyes as felt with the liii«ers through he ,,. H.riid. To .lo this, it is hest to employ th.- two index hn^eis ,, „ I ,.,• tinjiers heiii« spread out on the temple and hrow to atlonl , h s support. The' patient is direete.l to look down, ai.l slight J- e is made on th.- plot..- alternately with tlu- two tin^.Ts. 1 lie ..ree of tension d..i.ends not only upon th.- mtra-oeiilar pressure, ;i;;: "iKn:;.;;:;;;:. si,;.;;d o.. o.. .h.. lempie an,i u... t.. affo,., ti pre: llrio't:: '"r^ilMit ':V;;;a ■:;.; th^-elastleity ..f tl. selen-tie, wlneh vi.:' with. :;e,an.l also v.:ih the in.iiwd..il^ „. hiipovtaiit, there- fore, in esthnatin^r whether the tension ot the eye ^^ t^'f'^^ - t,„„ „„,,„al. always to eoinpare it with that ol the tellow eve, pn- siimin« th.'it it is unaltered. The (litTerellt dejlives of tension aiv noted as tollows: T \ Normal tension. T full Sli<'htlv more than the aveia,'.;e normal tension t' i \"-li"iit hut decided inerease ahove the normal tension. t'. -2. More'marked iiu-rease of tension, hut where the fiiifiers eau still sli'ditlv impress the jilohe. . , T. :{. ■increase of t.Misioii so marke (•cimplclc liic I'xamiiiatii III. ,\ v\\ iliiriii;; miiiutfiy tiir inicrior nf tlu' v\ Dm ai'iiiiiiit i)f cciiam optical lesion ich an examination rannot I,. l,y the nakeil eve, and the student will have to eall to his ,1 -I deviee whieli will .ivereome these and remove the hiiideraneew ppose his view hito the eye. Aithoiij;!: liie prineiples of siieh ulilcll o :; dr\ici su^Ijtesteil and near v attained l)v a mimher of early >iii'iitisis. the honor of perfeetm): an irii'iit lielollils to 1 elalHUatiii'' them into an instni- ,////,.// IIIIISCIIJM' 111 llelmholl/,. This distinfinished physicist invented th» 1S.")1, and l)V this instrument solved the prohlem of -.miiiltaiieoii .■illhoii v ilhiminaliii"' and viewinc the interior i.f the eve ^h the iiistriimeiit employed by him was crude and inetlicieiit iny wavs. it comprised allOf the optical principles of the later- iplithalmosco|M'. his instrument immediately opi'iied a new held The discoverv ot t Mill on Iv ii the studv of ophthalmolofiy hut in that of clinical medi- well. Conditions w iT the names of amaurosis aiu hich were ilescrihed by the older writers 1 l)lack cataract, terms used to li'-iLrnM te all forms of blindness the cause of which was not apparent ,f the aiterior segment of the eye, wore an examination o veil into vari( )Us diseases of the opt ic nerve retina, am", choroid. Ii WM- fniiutl, furthermore that svstemic disorders <|uite remote from Ihr v\v sue as a tTections of th<" kidney iieart, and brain, often pre- I tl'"ir !ir>t 'uamies •ount no routine examiii nil- :hm lie lim iKir i< a ciinician ju itations in the hidden tunics of the eye. I'pon ation of the i^\i^ can k' considered to iiiilil ii'iiii'ni IICIAI perlv performe.1 until the ophthalmoscoiM' has Im'cii emi)loye(l (•linician justified in rendering a diajinosis in many ca.ses is aware of the intra-ocular condition. It should be br'i-.'d that bv no other means is it iiossib'e U> sec a living ■ad and to study the complete vas( ular cycle in an orpaii, of llie elitl'ance o if its arterial and the exit of its venous blood. I.ike most instruments of a similar nature, its use presupposes :, rrtain ainoimt of prai'tice, and the student will succeed m anpur- inu' :iliililv to us(> the ophthalmoscope only after the exercise of I Mn-i.|rnil')le patience ami emleavor. One api)roachinL' its study should iiHi . ;imIv b(> discourajied, nor should he expect to become expert in IN M-.' ill a few weeks' time: he should sedulou.sly cultivate every '|i]i'itiii!iit y that jireseiits itself to e\;imin( tli(> interiors of healthy ir It IS only by a il ri.ndiliiilis mav be recoirnized kiiowleil<;e of the phvsiolojiical that patholo;ri .\rtilicial eve: .ire iif drciiled Value when it is imiiossible to obtain na such as 1 tural 'ernn s. eves for 1 J |.-i,iil |,rni.'i|ilosiiiV(ilveil In .jplnhrtlmoM-ni.y, thf llu'i.ry of ihe ophthnlmnwoiif. mid the • let. rin:^ iiiun nf ihf ri'fmotiun of the eye by it will bt coiisiik-iv.l in tliu I'hapter on Kelraclion. •M Tin: EYi:. stiiily, «>r a r:il)l>il's eve may l)c utilizi'.l. In on' t tliat tlic stuilciit niay'lM' lau'ilil accunicv, and Miay ai>|>ivciatc fully the iiaimv of tiic ciia'iijli's whicli the o|>liilialinosco|M' reveals In liiiii. it is a(lvisal)le li>r liiii '^..sketcii what ill' sees; for while but few persons possess sntli- cient skill to make an artistic .Irawinu' of the tindin-is of tlic oplithal- nioseope. nearlv everyone may proihiee a schematic rei)resentation (if I hem. especially it" lie employs a sketch-liook sudi as has been (levisecl i)V Haali. The writer knows of no nhjectioii to the student's inakinj; his tirst trials with the oi)hlhahnoscope upon eyes the pupils of which iiave heeii arliliciallvdilate,!. The employment of the instrument isfjivatly facilitated thereby, and the fact that he has once seen the fundus will enable the beLdiiiier to proceed with more conlideiice upon eyes the pii|iil--of which are undilated than he wiio has never experienced tile sensation of aetuallv viewin-i the head of the optic nerve and the retinal ve-^sels. To avoid any possible accident resulting' from the emplovmriit of nivdriaiics, individuals under forty years of ap' slK.ul.i be i-hoseii, and eyes which are free from external sifiiis ot ilise;i-e llomatropiiie in weak solution if irrs. ad. f.-.j i is a con- venient druf; to employ for this purpose, as it proiluces a dilatation of the pupil in thirty nVmutes. and its effects are very evanescent, and may be rendered -till more so by the instillation of a_i'ew ilrops of a solution of eserine loerine suljili.. ^M•. >s; a^i. y of nit: eye. 39 ni,,st I'ssciitial t'ciituivs in :in ophlhaliiioscopc. viz.: larficiicss of field ,,l view. iini|)cr iliuiniiiatioii. and the aliility to hriiis a variety of IriiH's licforc tin- sijtiitdiolc in tlic miiTor, witlioiit tlic necessity of iviHdvin; the instriiitient from tlie eye. When propi-iiy nianufac- i,,,...,i m, ,■ wl" these instnnneiils should la.-^t the averaj;e ophthal- II, u, ...i-; a lifeii.;," , , ■ ' , : „-lii'i iij,l,n , Iniosropc. As shown in Imj;. 11. the Loiinj; ,,.,! I.;, ,|,,sc.i|..' i: providetl with a coneave mirror, parallelojiram ill . , .with ,1 .-entral perforation from ;{\ to I mm. in diain- ,1,1 The mim.. is so hinif; upon the frame that it may he tilted ■_'() ,|ei;rees to the rigiit or to the left. For the purpose of focusing i,,»ring's ctphtlialnioscnpe. !;,■ r ■ !,■ 1- I'l |M| nhirl !,'ll-i I'aiii; C.I :: Tl ivs upon ihe fundus in the i-vent tliat the format ion (>f the ~ almiiinial, and secomlarily to oi)tain the dejiree of refraction ..1 the eve. the instrumenf is provided with a series of lenses V \»' rotated hehind tiie sijiht-hole in the mirror. These I i!ia\ ^ iiv .'ontained uiion a full disk and a (|uadrant of a disk, and iiniii the weakest convex and concave spiierical lenses to those -Mviiirili suflicieiit to iieutrali/e the lii^hest ocular defects. . \ln,i,„i Ophtltnhiioscoiif. (Fifi. !■-'.) In this in.struiuent the - !v —t in a <-v!i!!d,.r in the form of ail en-lless chain, and are pro- li'll'i i.v M siroiifi'drivinfi-wheel. The instrument is jirovided with tluv, miners— one plane and two concave, one of 10 inches focus and pflf m 40 a sniMllrr mw n\ ., Tin: i.Yi:. illl'lli'^ |(ICU~ Tlir t wo lust, wliu'ii ar '(• si't hack to ick ill Hill' iiKiunliim an I arc fcvcrsihlc, ar niil iviiiioscoiiv: tlic siiiallci- concave on( htliali (' for iiiilircct examination is for the direct iiietliod. has been introduced by Oiiite receiillv a stationary o, . , i i • •nionirnFi-.'i:ii.\vliicli.altlion};li too larp' to i.e .iianipuiate.l l.ytnc iiaiid and roii-.r>|uenllv valueless in ordinary rout,,w work, altords an un(M|ualled opportunil v of viewing the fundus williout annoyiiif,' Till' Miirl.iii ■.iilillinlniMSCopc. reflexes unsr<>iH\ i :i~ I'll' ilic mi'llidiis of oplillialmiiscopic cNaminatioii to lie prcs- ^'\ ii;i iiiiniicl. tiip |iati('iit sliodld 1)(' scalcii in a darkened rodin, ' I liiilit pliiccd a little l)eliind tlir head and to the side of the eye 1 \:iiiiinalion and njion a line with the ear. .\n .\rgand limner IhciiHiociMlt cuil lor i'iihIhntiiH»i'"l'.v, ■•:i;|t!i...-.-J^.<.'^?iL''; :•'-.- -^ 42 /■///•; K17v. li.rht and (lavliRht mav Iv (■ihi.1...vc(1 hv p.Minitting the rays to f;am rulraiur into" tlic room tliroufjli a narrow slit ni a l)lnul or stmttcr. Sui.li<'lit i< to l>c prclVrrcl when it is .Icsiral)!." to study clianpcs n. tlic tundus as ncariv as possil.lr in their natural color, as m ana^nna. If the patient he l)odri.l.lhe.l all that was possible uiu ler the cir- cumstances, la the ])erformance of all onlinary tests \yith the oi. h- thalmoscoix', the observer should b." on a slifilitly higher level than the P'lti.'nt and both he and the jiatient should be comfortably seated: the cu.s'tom which prevails in ;oine Jilaces of the surgeon standmfl and bendinji over the patient's ey is ,leprecated as timdinf; to favor hurried an.l sup.Tticial examinations. In exaimmns chihh'en s eves the p.ilience and iiifrenuity ..f the observer will often lie taxed l„.f,,re a -atisfactorv view of the fundus can be obtained, aii.l a third ...rsnii is often ne("essary to attract the tiaz(> of the child trom the liirror towanl some distant object. ., , , In examination with transmitted lif;ht,the student, with the larfje eoncave mirror of the ophthalmoscope held clo.se to his eye, throws the li^rhl upon the eye under .ibservation. the patient bein.sj; instructed to direct his <:a/.e in front of him. , , , , ,■ \ faint pinkisli-re.1 glow will be seen to replace tlu- blackness ol ,1„. pupil. This is know, as the iimJns rvjUx, and is occ.-isioned by the reileciion of liuht from some i)art of the illuimnated interior ot th,. eve With the 'iuht from the mirror still concentrated u|)on the pupil' the student should now tilt the mirn.r in difTerent directions 'md WW the .•hanicter anarts of that membrane. \\\\\\' use of the mirror it is also jx.ssible to determine ///<■ jixntion noiul This is done bv observin.-; the coriK'al retlex. This method, ;,tt..nlion to which was called by I'riestley Smith, is practise.l ni the lollowin- wav the patient is told to look at the mirror; the hfiht is tlu'n thrown"ui)ononeof the i)atienfs eyes, am! the exact position of the lifjht reflex upon the surface of the cornea noted; the student then quicklv turns the lisiht to tlii' other eye and compares the .osi- tioii of the'corneai li^dit re(1e\ in the two eyes, 'ilir corneal < Hex L',-nerallv api.ears a little nearer the inner than the outer clue ot the piijiil as the visual axis usually lies to the i...ier side of the axis ot T^rssr. - sc-"S^'?=^iij«aB*-' ■ i:x.iMiyAriox of the kye. 43 ihc ciinica. If hdtli cyos ho properly iliroctod, tlio position of the (■(MIii'mI rcH(>x will he syiiinictriciil in the two eyes; but if one eye ilrviatcs, tlic reflex will he ilisplaced. I.i this way imperfect fixation ill >trahisnuis w'"' he readily detected. H\- transmitted li^lit alone, the presence of npncUies in the mediu may lie diagnosed; these appearing like dark shadows in the red iKickjirouiiil, because the rays of lifi;ht as they return from the oye- ^'nuuid are arrested by the ojjaiiue spots in the media, just as all (iliiicts which do not transmit light api)ear dark when seen in front (if a luminous surface. .\s th(>y often are seen best with feeble illniiiinatioM, it is well to substitute the |)lane mirror for the concave ill searching for them. With a view to examining the media more closely, and to ascertain more definitely the character and position of any opacities, the student should now rotate a high convex spheri al liiis berorc the sight-hole in the o|)hthalmoscope and approach the . \r until he is witliin the focal distance of the lens. For this purpo.se, Flo. 15. l>iaj;iiosis of the site of iiti (»|iurity from [laratlactU' ilisplticenipnt. iFl'CHs.^ iIm' Moiidu ophthalmoscope i< priividc<| with a lens of ,") cm. focal Iriiirtii ! -jn D.I, the I.oring with one of ().2.') cm. (- Ki D.). I'nder ihi- high niagnihcation any foreign body or opacity which may have iidii (ivcrlookcd usui'lly becomes visible. To determine the exact '■H-Miiiin of opacities is often diflicult, and careful observation is re- . ;iirii to state iletinitely whether they be in the cornea, in the anterior I "iii'iii (if the lens, in the posterior portion of the lens, or in tlie an- I liiii- pdrliiii of tin vitreous. It may, however, be stated as a ■.'1 ' ' Till rule, that stationary opacities are in the cornea and lens, and i!i.!i nj.acities in the vitreous, although ;it times fixed, are usually ll'.-.'iiiL'. It is fretiuently possible al.so to determine tlu' location of an w]iiiii\ by comi)aring its i)osition with other structures in the eye in i!i<' - iiic iil.'iiie, as, for example, the conjunctiva and the limbusin cases 'if iijiK iiy of the cornea, and the iris with the anterior part of the lens. \ \. I \ ■icr-iirate. and at the same time a very simj>le mode of loca- tiiii: till position of an o|)acity is by mean.s of the jHiralloctic displace- im III iif the of -ty with reference to the margin of the pupil. Iri 44 77/ A.' KiK I'lfT. I.), 1, 2. .i. 4 n'prcsciit I'diir n|i;ii|iic [loints in tlic (.|ilic;il ;i\i^ "I the vvi; sitimtcil in the .•<,nic;i. u|),,i, i!,,. aiitcridr (•.•i|.sul(. nf the let's, at tlic |)(,>trn,,r p,,!,. ,,f il„. l,.|,s, and in the anterior part of tlie vitreous, resp,Tlively. W lien tiie ol.server is stationed at U all • •ur ponits will I,,, nierfred, and he will see l,i,t one. Should, h.nve'ver '"' '.'"'^'W* '*• "'•'" ""• l"'^iti<>ii nf these p„ints in relation to the I>iipil will he ch.uijred. Thus. 2 will remain fi\e,|. while 1 a|)proaches tlie upper. an ophth.almoscope. A.s has just lieen de.s'cribed, the red reflex <•! the lundus will at once become visible; but unless the eve bo iijlhly nearsiKlit.'d, nothiii}: more will be ob,s,>rved unless ji nmvex lens of about o cm. locus l)e iiiterpos(>(l before the eve and held at Its focal distance. If |h,s be done, an inverte.l imajre' of the eve- jiround IS obtained, which will be seen between the lens and the slu.lent s eye. Some difficulty is usually found bv the bejiiimer in .■H-eomphshmfr this, on account of reHectior.s from the surface of the lens and the cornea, and his tendeticv to accommodate either for the ey.' or the auxiliary lens. The refl.Ttions mav be overcome bv -entiv tiltins the lens from side to side, by bearinjr in mind al.so'that the nnajie o| the fundus is ,an aerial .me, au.l bv inakinjr an attempt to ad,iust the eyes, both bemjr kept (.pen, upon a point between his own e.ve and the lens; the latter dilhculty may be dispelled also and he will avoid the natural tendency to accommodation. In •■xaminin-' the eye. the student should apply his rijtht eve to the si<:htd.ole in the niMTor. the msfrum.Mit b..inf; -nisped bv the ri;;ht han.l while the auxiliary lens ,s hel.l in the left. It is advi.sabl.. t<. steadv the hand which holds the MUMh.irv lens by resfn- the tij. of the little or rinj: tinirerui.on the patient's brow, and to utilize one of these finders to rai.se the upper lid wh.'ii it is desirai)le to examine the lower pan ^ff hXAMf.XATIOy OF THE EYE. 46 ..1 ihr (vc, or if tlic lid is covcfinj; tiic pupil, ;is is frctiuciitly the r;i-c ill iiill;iiii(Ml eyes. If ihc ri<;lit eve is iiiKJcr cxaininatioii, in order to hriiij; tiic iicad ,.| the optic nerve into view the patient siiould he toltl to diri'ct iiis ;;:i/.c at the raised little finj;er of the observer^ ri>;ht hand as it grasps ihf lip of the handle of the ophthalmoscope. When tiie left eve is l.( iiiii exaiiiiiied, he should look at thi observer's left ear. riie indirect inethoic cxiimination. 'I"; 'linTi niethoil. By this method the image of the fumlus is mag- "iii''l about five diameters, ten diameters le.'is than bv the direct "" iliod, but greater magnifieatioi, mav be obtained o"^f the aerial iin:.-r hy rotating a -r S 4 I), lens before the sight-hole of the ophthal- i!iii-r(i|-iic mirror. It .-liuuid i„. remembered that the image in the indirect method is ■ tn inverted ,,n(>, mid that, t.-erefore. the u])i)er part of the image cor- |'-p"ndstothe lower part of the eye-ground, ami the right .side of the '•'■'■"■■ '" t':,- left uf the eye-ground. It is e.vlremelv useful in 'A-niiinmg patients in a reeuml t posture, ami is very Valuable in '■\:iiMiiiiiig the eyes of children, as it is often impossible to obtain a 46 THE EYE. view (if the fundiis in this class of ciiscs l)y tho direct method, on account of tiic iiiipossihility of iin>; thcin iiiiict. On account of its fircalcr niapiifyinj; power, tlie direct nietho