UITC fELLGUkj

USAARL Report No. 89-1

I I

Anomalous Retinal Correspondence(Reprint)

By

Morris R. Lattimore, Jr.

Sensory Research Division

DTICAfELECTEK

October 1988 24J AN 199

E

89 1 23 146Approved for public release; distribution unlimited.

United States Army AeromedtIcal Research LaboratoryFort Rucker, Alabama 36362-5292

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Released for publication:

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Anomalous Retinal Correspondence

12. PERSONAL AUTHOR(S)Lattimore, torris R.13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE COUNTFinal FROM TO 1988 October , 11116. SUPPI.EMENTARY NOTATION This work was done at the University of Houston and this report is areprint of a publication in Southern Journal of Optometry, Volume VI, Number 3, Summer, 1988

17. COSATI CODES 18. SUBJECT TERMS (Contnue on reverse if necessary and identify by block number) -FIELD GROUP SUB-GROUP anomalous retinal correspondence, strabismus, diagnosis,06 04 therapy, theories0605

19. ABSTRACT (Continue on reverse if necessary and idenify by block number)

_- This paper presents an overview of anomalous retinal correspondence in strabismus.Definitions, certain testing techniques, and a review of underlying theory are outlined.It is concluded that ARC is not well understood and represents an area still open forinvestigation. ...../ N ,V7 ',

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Abract. This paper presents an overview of anomalous retinal corepondence ian strabismus. Definitions.certin testing uhniques, and a review of underlying theory are outlined. It is concluded that ARC is not O Iwell an pid resl'emalB anl area still open for invesagmaiua K._L, ,J.)r . ', "'

SI .PECTED

INTRODUCTION with fovea-to-fovea correspondence (Davson. 1972). Simi-Anomalous correspondence has been a topic of con- larly, it has been defined as a correlation of retinal points

siderable interest to both clinicians and vision researchers with identical local signs or visual directions, with the fovealfor quite some time; the result is a variety of strongly held direction designating "sraight-ahead" when at least the domi-theories that tod to be contradictory. Some recnt excallent- ran eye is in the primary position (Moses. 1970). That is.ly detailed reviews (Nelson. 1981; Jennings, 1985) have ad- an image falling on the right fovea will be perceived to bedressed various areas of research. However, anomalous cor- in the same direction as an image falling on the left fovea.respondence transcends several research arenas; the object This normal correspondence can occur independent of oculaiof this review is to correlate findings from several disparate alignment. Electrophysiologically NRC has been defined as

- disciplines into one parcel, the convergence of essentially monocular neurons upon a,inocuar single vision normally is obtained on the horop- single binocular unit in striate cortex (Nelson. 1981).

ter. a locus of points in space whose retinal images fall on )_Anomaous retinal correspondence (ARC) describes thepairs of corresponding points. A stimulus affecting one cor- V condition in which a control mark seen only by the deviatngresponding point will be localized in the same direction as eye of a squinter is perceived in the binocular visual fieldif it had affected the other. The horopter, however, is a in a direction different than that to be expected on the basislimited construct for describing the process of binocular, of normal retinal correspondence Ales.-9 The spatialsingle vision; a disparity range can be added via sensory fu- I localization of the deviating eye appears to have partially orsion. Moreover, since sensory fusion does not cover a large fully shited, so as to counteract the effect of the ocular devia-range either, suppression can be used u a further supple- tion. This shift in directional localization is termed the anglement to avoid physiological diplopia. This normal use of sup- of anomaly. If the angle of anomaly equals the angle ofpression can be enhanced by nvalrous conditions and has squint, then the anomalous correspondence compensates ex-been posad to pI& a role i stabmus.IHalldn. 1982). actly for the squint and is described as harmomous ARCii'h- iismusiid tIith line of sight of (HA). Ifthe angle of anomaly is greater than zero. but less

one eye fails to intersect the object of regard. When than the angle of squint, then it is described as unharmon-strabismus occurs in early childhood, certain adaptations can ious ARC (UHAC). If the angle of anomaly is in the op-occur. Possible adaptations include amblyopia. suppress posite or noncompensating direction, the correspondence isand/or anomalous retinal correspondencC Thii'-per will described as paradoxical ARC (PAC) (Borish. 1"70).be limited to a discussion of anomalous retinal correspond-ence. However. it is clear that strict isolation of the possible THREE COMMON TESTING TEC-NIQUESadaptations is difficult. A variety of techniques, designed to evaluate retinal cor-Normal retinal correspondence (NRC) has been specified respondence, have been devised. Each testing methodology

in a number of different ways. It has been defined as a appears to be influenced by the specific definition of cor-physical point-to-poi matching of the retam of the two eyes respondence accepted by the developer. Testing techniques.

in general. can be reviewed in Borish's C7inical Refnctwn amblyoscope. A small suppression zone. not noticed by the(1970). from which three common testing methods are out- patient, can be missed if a critical examination is not per-lined hee (Table 1). formed. By avoiding dissociation, this test allows a deter-

The Hering or Bielschowsky (1937) after-image test is mination of correspondency under normal visual conditions.often used clinically because of its simplicity and apparenteffeciveness in determniing retitol correspondence. A brightlumi-line fuament or flash attachment is used, with an oPa- GENERALIZED THEORIESque spot or band at the midpoint of the filament. The sub- The earliest theories considered ARC to be innate and im-ject fixams the center poin monocuarly in order to achieve mumble, reflecting a congenial anomaly that was untreatablethe a ter-ima. This is commonly done with different orien- (de ia Hire. 1730; Muller. 1826). Lawe support for this viewtaions for each eye (nma: For correct interpretation of this suggested that ARC was the underlying cause of squint intes normal or eccenmtc fixation must be determined prior cases of large angle. notiacc-Mmodative squim (Adler andto applicr..) If correspondence is normal the two after- Jackson. 1947). Failure of normal correspondence to develop 0

images will form a cross; if correspondence is anomalous postsurgicaly also has been blamed on a congenial ARCthe two fixation points will be separated. (Bedrossian. 1954).

An amblyoscope can be used to determine the objective Later theories held an alternate view that retinal cor-and subjective angles of deviation. By presenting different- respondence changed as a sensory adaptation to the motorly oriented linear targets to each eye via separate arms of error or squint so that there was a shift in the visual direc-the amblyoscope, measurements can be made quickly and tion of one eye relative to the other eye (Burian. 1947). The-asly. Problems, involving e failure of mage super- basic idea was that correspondence could be adaptivelyimposiaon or suppnmioo of one image, may ocr and pm - modified over some learning period m early life (Walls,vent the diagnosis of ARC. 1951). Burian popularized the idea tdt ARC b ecome more

The Bagoli striated glass test (Bagoiim and Capobian- deeply ingrained over tim and that ds can be quantfiedco, 1965) makes use of piano lenses upon which sriations or graded in terms of the nanre of the stmiulus conditions0.005 mm in width have been inscribed. The striations are under which it persists. A common testing hierarchy has beenuniform over each eye, but the axes of the striations are suggested to test the "depth" of ARC adaptation: the Bagoinioriented 90 degrees away from each other. The viewing of striated-glass test being proposed as the most sensitive meansa small fixation light creates the subjectve observation of of eliciting ARC. the synoptophore or amblyoscope test pur-two blurred streaks with the res of the visual scene appear- portedly exhibiting a mid-range sensitivity, and the after-ing undistorted. If the two streaks cross at the fixated light. image tes being the least sensitive. Patients exWbin ARCthen the patient is exhibiting either NRC or ARC, depend- on the after-image test were taken to have a deeply embeddeding on whether a squint is absent or present. respectively. ARC of long standing (Malle. 1970; Bagolini. 1976). How-Suppression can be a problem, but less of one than for the ever, the depth of anomaly theories have been questioned

Table 1Three Common Testing Techniques

TEST DEVICE PROCEDURES RESULTS

After-ifmage test Bright Lumi-lne filament with an Fixate honzontal filament with NRC: a cross is seen.opaque band at the center. preferred eye.

Then fixate vertical filament with ARC: the two lines are apart.nonpefernm eye.

A ysop Major Amblyoeope Set arms to objective angle of NRC: a crosis seen.Squwnt.Present a vertical line to one eye. ARC: the two lines are apart.and a honzntal line to the otier.

Present ins. le patient set arms NRC: if the sublactlve angleso that a cross is formed. equals the objective nle.

ARC: subjective an objectiveangles are unequal.

Bsagolini lens teat Striated lenses and a penlight. Fixate a small penlight while look. Squint present: ARC. if luminousing thru the Striated lenses with streaks cross at fixation point.axes onented 00-45; OS-135. NRC, if they do not.

Squint absemt: NRC. if luminousstreaks cross at fixation point.ARC if they do mot.

2

(Flom and Kerr. 1967) based on measurement errors. in- be totally artethcwal because the different tests are evaluating

steady eccentric fixation. and changes in the relative posi- different aspects of visual system perbormance t Duke-Elder.tion of the eyes. 1949).

Another theory was the replacement theory of Verhoeff Counter to all the adaptive or sensory theories, a motor(1935. 1938); retinal correspondence was said not to be theory has evolved suggesting an ARC that varies with thegeared to sulmerve fusion. but merely to perceptuaUy relate sensed position of the squinting eye. Briefly, eye positionpoints on each retina on an alternating basis. This idea information could potentially change correspondence by in-represeoted the firt modem rivalry theory of vision. Brock tluencing the correction from ocuo-centric to ego-centric

(1941) esaentially agreed with Verhoeff. suggesting that localization. In other words, the motor innervational pattern

anomalous caes develop the ability to identify spatial is proprioceptively registered so that the -urned eye reportslocalizatio separately with each eye. As an extension of that what it sees is displaced with respect to the other eyeVerhoeffs replacement theory Travers (1938. 1940) pro- (Duane, 1932). There isdeb as to whether there is an ade-posedthatthe diplopiaofasquinmerwas relieved by the devel- quate proprioceptive system within the extraocuar

opmen of a suppreaio scotoms at the fovea, which sequen- musculature to provide such registration. Morgan (1961) con-tiaily spread across the eye until the development of an sidered eye movements and eye position to be registeredanomalous correspondence resulted. Since this was pre- because of innervation to the extraocular muscles: in effect

surnably a slow process, findings of unharmonious ARC, as an efference copy signal.

wel as harmouism ARC, easily could be explained. The urn- Boeder (1964, 1966) proposed a slightly different motorplication was that the harmonious ARC was a completely theory whereby a response shift always results when the eye

adapted sate, while the unharmomous ARC was a condi- is in a position different from the one called for by ocular

tio dm wast al in ta~d (Roum and Rindzius. 1953; imeratio Boer fee that confirmation of his reponseCasheil and Durram. 1980). it was therefore assumed, similar shift hypothesis can be found in certain visual attributes of

to the Burian theory, dat the longer sanding and more con- the strabimic paent pas pointing, monocular diplopia, andstem the quint, the deeper established the ARC will become strabismic amblyopia.

(MalleR. 1970: Bagolini. 1976). Motor theories. in general, provide for an incorporation

An alternative adaptive theory has been proposed by of an awareness by the visual system of some sort of

Nelson (1981) suggesting a disparity 'modal tuning" kinesthetic signal. or an efference copy signal which allows

mechanism that responds globally to the most active disparity a correspondence shift to take place. General motor theory

contour. As a result, there is a wide range of potentially cor- evidence is the maintenance of correspondence when an eyeres states: specific conditions govern which cor- is externally moved by tweezers grasped onto the conjunc-respondence state would be expressed at any one moment. tiva when under local anesthesia: such an experiment actsAn intrpret'on of Nelson's theory is similar to the to eliminate both proprioception and efference copy (Pasino

hysteresis effect reported by Fender and Julesz (1967) with and Marain. 1965).random dot stereograms. Once fusion is established, it can Both general theory types. adaptive and motor. havebe maintained through an induced range of increasing dispari- specific merit; clearly additional work is needed in order toty; once fusion is lost. the disparity must be decreased con- reconcile the data. Initial attempts to tease out" the deter-siderably before fusion can be reestablished. There may be. mining factors have met with mixed results.perhaps, a flexible and responsive stretching or shifting in One means of differentiating the underlying issues is tocorrespondence that is capable of occurring only under determine whether there is a fusional movement of the eyespecific conditions. Indeed. Campos (1982) has shown that or a change in correspondence when anomalous binocularstrabismics have a wider Panum's area than normals. As are vision is maintained under altered viewing conditions.several other theories, this is consonant with harmonous Marani and Pasino (1964) tried to separate the two possi-ARC paem remaining harmonious despite the angle of bilities. An after-imae produced around the fovea of an ARCsquint changing from far to near, looking up and down subject's deviatng eye was located with respect to a fixation

(Mallett. 1967: Bagolini. 1976). or with and without spec- light viewed binocularly throgh Bagolini-striased lenses. Thetacles (von Noorden. 1967). In support of the responsive cor- introduction of six prism diopters base-out before therespondewe shift theory is the finding of Maraini and San- deviating eye of an ARC strabismic would have two possi-

tori (1967) that ARC spontaneously may shift to NRC when ble effects if anomalous binocular single vision is maintained.the patient is forced to fixate with the normally deviating eye. If the after-image to fixation light separation remains cons-

Nelson (198 1) also proposed an alternative explanation for tarn. then a compensatory fusional movement has occurred.the varied test results that Burian ascribed to a deepened If the after-image to fixation light separation decreases byadaptation. Nelson suggested that the varied stimulus con- six prism diopters, then a compensatory shift of cor-

ditions differentially stimulate a global match response. The respondence has occurred. Of eleven subjects evaluated.stimulus condition that best allows global matching to occur three showed a compensatory fusional movement, fourwill be the most sensitive means of eliciting ARC: converse- showed a compensatory shift in correspondence. and the

ly. stimulus conditions that prevent global matching will fail others showed a combination of the two. Other studies have

to elicit ARC. Others have suggested the varied test results to shown similar conflicting results (Johnston. 1970: Kerr.

3

1980: Kenyon. Ciuffreda. and Stark. 1981). Since neither surprising that certain strabismics exhibiting ARC have aadaptive nor motor theories could be ruled out by this in- rudimentary stereopsis in the threshold range of about 100vesugative means, it is unknown whether they apply to ex- sec. of arc and exhibit some coarse peripheral depth sen-tremes of a single populam distribution, or to separate sitivity (Helveston and von Noorden. 1967; Epstein andphysiological conti . A similar parallelcan be foundelse- Tredici. 1973: Henson and Williams. 1980: Sireteanu. 1982).where in the vision Literaure; anisometropic amblyopia and If it is accepted that there might be multiple. overlappingstrabisnmic amblyopia have been suggested to represent ocular projections to the cortex, and if those inputs mightseparate conditions with overlapping symptoms. be predominamyof the 'Y-type" classification, then it would

Al of the sues raised thus far have been based on results be reasonable to suggest that there is a dual neural alterationusing subjective mzthodologies. Issue clarification might be in strabismics with ARC. This dual alteration would exhibitotaine. via objective evaluation techniques. Visual evoked itself as being able to provide only coarse. peripherai stereop-potenmal data could prove to be useful since scalp topography si; however. within this coarse framework the visual systemof the VEP is known to reflect retmotopic mapping in the may be able to shift correspondence tining within the rangesvisual cortex (Jeifeys and Aiford. 1972). Campus (1980) of the broadly overlapping cortical projections. along the linshas detected binocular enhancement of patlern VEP's in ARC of Nelson's sensory fusion theory (1981). The resulting cor-subjects. and also has routmily found binocular summation respondence would only be 'anomalous' with respect to theof VEiPs in the same subjects (Campos and Chiesi, 1983: expected fusional limits demonstrated by "normais." SinceChiesi et al. 1984). Yet. psychophysical investigations have *Y cer input is provided both to the cortex and to thefailed to reveal any kind of sumtion in ARC sobjects (Levi. superior colliculus. it is possible that some sort of signal1987); very recent e . ymopkaoiol dam, as well, have gatng might be responsible for a sensory system and motorsuggestd that VEP sumimn is not repratentative of the system numb-ln this manner both sensory adapusimm andactivation of binocular cortical nurom (Shea. Aslin. and motor adaptations could work in tandem to provide for aMcCuUouch. 1987). Additionaily, McCormack (1987) has shifting in correspondency. The concept. however, does notdenstrated that VEP scalp topographies do not differ for fully address motor theory ium. which are very important.separate foveal stimulation of each eye in an ARC subject.

LABORATORY STUDIES THERAPY

The field of elecrophysiology also has attempted to analyze Theories regarding the treatment of ARC are as corn-the processes governing the developmern of ARC. Animal plicated and confusing as the theories regarding the under-experiments have suggested certain criteria are necessary for lying mechanism. The specific therapy techniques can in-ARC development (Nelson. 1981): strabismus onset must clude: the application of prisms, the prescribing of partiallybe within the binocularity critical period, the strabismus must corrective lenses, the stimulation of stereopsis in a peripheralbe small or gradually increasing, and cortical input coMpeti- to central fashion, occlusion. bi-foveal stimulation (either intion must be balanced by having equal levels of monocular or out of instrumentation). the use of ater-images. auditorysumulation. The last point is perhaps the most important. biofeedback, as well as surgery. A large part of the literature

It has been shown that there is considerable overlap in stems from anecdotal clinical case reports.ocular projections to the striate cortex that have withdrawn Many of the treatment modes have approached therapyby termination of the binocularity critical period under nor- with respet to the motor theories (Boman and Kertesz. 1985:mal conditions: induced strabismus has been shown to create Kertesz and Kertes. 1986). Veruence movements, either fu-an ocular dominance shift with the nondeviating eye gain- sional (Kerr. 1968) or accommodative (Daum. 1982). maying cortical connectivity at the expense of the deviating eye be registered by the visual system. and could thus be(Hubel. Wiesel. and LeVay, 1977). The presence of a stra- manipulated to stimulate ocular alignment. Sensory theorybismic condition, which meets the denoted criteria for ARC applications have also produced success: traditional amblyo-development, might interfere with the process of ocular scope therapy has been used to establish NRC superimposi-dominance shifting, so that when the critical period is elapsed tion (Griffin. 1976). Other treatment modes have sought tothere are multiple, overlapping connections that are not pre- employ both motor and sensory aspects (Brock. 1941:sent in strabismus with NRC. Walraven. 1957: Ludlam. 1961 Wick. 1974 and 1975).

Surgically induced strabismus in both cat and monkey has Treatment success is. however, another area that is openbeen shown to differentially damage the X- visual subsystem to debate. Reported cure rates have varied from 5% (Flom.(Brown and Salinger, 1975: Ikeda and Wright. 1976). Since 1969) to 85% (Pigassou-Albouv. 1973). Unfortunately. thethis subsystem is characterized by exceptional spatial resolu- definition of a cure varies from study to study. Other iam-tion and by fine disparity sensitivity (Poggio and Fischer. portant factors that obsoure the effect of treatment are: the1977). it is possible that strabismics exhibiting ARC are method of ARC diagnosis. and the means of demonstratingresponding primarily via the -Y" visual subsystem. Since the NRC. Further difficulties consist of: a lack of clinical trials,-X- and "Y" subsystems have been postulated to provide the possible experimenter bias. and poor experimental design.substrates for what has been termed *fine" and 'coarse" Future work will need to address these issues.stereopsis. respectively (Bishop and Henry. 1971). it is not The implication is that the management of ARC is not a

4

sumpie matter. Carefu diagnostiic testing. under a variety of el...laWIhi.orusmDI SW.1Oplabslmul. 64:349-353.

condiifons. is necessary to correctly con&-mfl the PresecelC HaWe. D.H.. Wisid. T.N.. &Wd LAVav. S. 19IM Pluacag of aeu~a domnanc

of ARC. Thermp requires the Integration of both adaptive conm ua molr mum * con h Trin Royr. Soc. Unue B. 27$:377.49.Mob. Hoto an Wr#I .196 P ope.u of LGN cells a kan ,iWall

tively.es. 25:63.77.tively. J~eftera. D.A. ankAxilab. J.G. (19721 Souiteizz ation;of~poeafc COm-

Pomn= of b av.owa PaINM.1. Component o( strm coined ongm. sp. Sain Rm. 16: 1.21LI. Coemponent of emtastrune cortial orign. Esp. Seaus Rem. 16: 2-140.

S'mb"RY Jefmop. J.A.M. (1981 Anomalus n ia contspobemeo - a revew. Optasim.Theories ~ ~ ~ ~ ~ ~ ~ ~ PbW oft A5:a3itotobodcaeois3enoy ~S7-3U.Theoies f AC f~ll nto wo boadcateorm senory Johnsio. A.W. (1970M An anlysia of chamma nor results for hnmlous cor-

adaption. and moto response changes. Up to this point respam. AWJA . Opeoft 53:33-56.UsMeM modes hMv Mg with mnimail overall Success. Kenyan. LV. Ckabee. Li.. astarik L ( 19861) vug Vat "M

in i A a~tpin mamorc erlos.Di. J. 0a1nod 65:107-176.largely as a result of t lack of any kind of consolidated Ker LE. (196S) biity oanmusrondbcepmm 1 . Am. Ops.

model for ARC. Certainly, a major. organized, invsaw Assoc. 39. 1107-1106S.

tional effort is ziequIred if thes issues are to be resolved. Am. .(190) m w sd Opt. b 57: u 67640.m

Kaom A.S. sad Kism. J. (1936) Wide-field hiial annotam inmaAm. J. Opens. Phlysaio. Opt. 63: 217.=.2

LAva. D. (917) Paraso repon.REFERENCES Lle.W.M. (1961) aibc um~of whem Am. J. Opm. Arch. Aced.

AEW.PH. ~. .S. (96) Camlbume uamm me, ae mro . 38:369.388.Adlr.F-I mdiaios. -L(1%)CnvkmbM3 5 2m9w3gw Mallon. *.PJ. (1967) ARC sad Sapam staie lerm. Opladainuol. Optican

tom us- 3. C po. Nr. 1965) GI 38:299000.came aua: 7:164-166. Ai u ma.-b-wmo.Opl

iag. 3d1976) P.40eL aad hm (mIin . (gA j*403t 4121-624.Bap, .(lMFit L omin somae. n Opin 41:-22 PUOW- Maso. 0. an Vioist. L (1966) Variaion ab do in*@ at fehoun

ammoim, = (mnanm D.Opldoinm, 1:23-l. mmin at aom of am" mg* cammwe m Wihmoowina~me nmo d(* tow In~ '12.1 Om J. ()pdada 48439-443.

Smirooem. L.11 (19S41 Asim foma egms eab wabtonea Mm. 0. ad SomLn M. (1967) A 8~mno ad -ogiwMAlf. OPh*AbOO52.660M *a&B.lmiaoo. 5:7-D

0, u .. .. A. (1937) Appliation at do glw-inp m is db 10eatni Of Mcom. Opu. pm 15:79l3 19MNvn ewrw pli ua wb ihACaquis. Arch. Opldobimi. 17:3. !coue.019mNnalfwmpcmpu

Bishop. P.O. an im y. G.1. (1971) 5pandvuaon Aim. R9v. Pavcho '2-:119-160. Inow.'P eied A .ugt lro.M.W. (1961) Ammoiulmcapaeeaarbmaorplim

Booe. P. (1964) Aom r cr ipedn rA.I Oblao AIG. J. Opim. Arch. Ace. Opso.. 32:131.148.3$:366-373.

ImW. P. (196ffSWbo) m ami0 blbbwvu dipanarnAsal oimol 61:73-86. Mowm. L.A. dI9M0Adue'a laymbagyafew Eye. rrAiC.V- MIoy Ca.. Sam Lams.3m. L ~Keam. .E.(195) PamamI map..m of~ ~pp. 133 ade 668.

Brow. DK. nd ara A.L(19) Psio~i m 26:Of 73abmm17ldla. Moller. H. (13261 I Dabepma. P.C. (101) On die anmlies a( acamadetwoade iixa-,bead oailmou lave. Opladalmi. Via. Sc.2;13-79 ajel 1e0m- ie nea. pp. 251. The New Sydem Sociey. Londo.Bartel. L.M. (1970 Clinial 3arsin 3rd ad: Pp 1233-1240. P (maimeibe Press. Sdbs. LL 11961) A ipy Mod (Or WAerInim npa Wl~

lu., F.W 91 c.iemt-ma m~~ pn.wby an Im C of memory fus. Doe. Opheaimol. 31:3-9,32:793401: 819424. fdavLmiau.0.(95 ipelaed.efer nanb

Brown. 0.L abeSalasge. W L (19751 Lamof Xcela in (aural geucuim mina-law.R 173 h s o wrcman rsn ote OWhmo~mia aey: niaaP ' Ito v baid car. sciene. t 99: 101 1-1012. PushaM mey ft. , (193)l. nas AlbaetcovnColas ta ic MO. be ouam. o

Reman. N.. (1947) Suanartaaareiaaadsomha m conmmi u,.aaaM. Arh. 1116:209-226.lbmemGat ~cl.Klt.OpalmIOphshalmod. 37:336-368:.304-533: 618-668- MP 9p6. adFshrL (1977) ne ontta m no~ w

Campos.~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~o E..(971Aoadwrtnlvugd- mW n "10" n ramsesoi fbhi Ale , m. - Nrupwvl. 40: 1392-140.evoked. Na.C. m Arch. ophininanol. 96: -99-302.fd Roome. 0. abe fIoa. E. (1953) T1w dispoe abe claacal clmaalinooe ofCamos.F-C ("M limcaaim -oo wemm bag~i' is~ual anmaou - I I .m Acts Op(ltalml 3.2135

sadmes. Doc. 0 . 53:249-231.Slm .. Ad.R.ra culahD.191nBouarVPsmei iCampoe L.C. said Chum.. C. (1963) Selamalmawy us com m ams. Do. Shesa a.dulAs~ LN" abnoma M nc~aiea D.iom lo9est Buoaalw VIP ma.ma Son

Opan 55:77393 In b IewdeeulIie w~m ma.Ollei i.SaCashe. 0.TW. ad DOn. I.M. (193071 In klbo@koOikopw Prcpi-t .9:336-M6.

ad. CbaU Lavagm. Ed~brgia. .Sirea. ft. (191 Bjinocuaer va o sabaams humn -ich Qleaa fltion.Clad. C..urchill ALi . ab ERbin t. (94 mnarmmletpoin vis3l. 2:9896%.CharC. surme. b.D. mad MUM A.ee (1984 repimA.W DoSN.I Pecpimo Traersl. TaD. (1933) Seappremma of voas in square andit asseccation with retial53:5 sd1-5en 0' a ro6.. o.op"iord .ciapea mo nblyopt. Oft. J. OphinIalo. -12.377-604.

de8:.1-56a. (70 em. abe.(12.Panbpieaeme Travema. 73. (09401 The ong of ashaowing rena apmie .Jdswmp~m Ais IOpn. S130eQadal. 37:21.93. peoen WMC OplmioU. 24:58.64.

1 ~ ~ ~ ~ ~ a ' menmamaivd Spp.371.3 Verhoeffe F.11 (1935) A mew beamy a( bomamer viaio. MArc. Opicabuaa.Dm. KM. gl9V)C -m',moomaom pe I wisaaem~ 13: 131-17S.Verpme. AL J. Opuam. Phyua. Op..9146-131.Dava. (4. (19721re PhyasoMh of the By*. Aialmoc Prins. New York.- p. 47. Verhaa. P.H. (1933) Anmau propenm aid other visual p9nea assocated

~~~~~~~~~. ~ ~ ~ ~ ~ ~ wt A.(92)Dpipeao-mmlb VbemaetpmlOs & Arch. Opialiamk. 19:663-699.238.Dmm . ("2) oicpm ed oher f budw 1100- Ach- Vain Nom. 0.K. (1967) Discussion o Bagaln. Doc Ophtalmal. :38Opilml. 7:187-210. Wales. G.L 11951) The uIm1 9( wand diretons.

Dubm Elder. W. (1949) Tazikairk of Op1aolaolgy. C. Mby~ Co.. S'. Lanm.Spew.n. D.L and Tibet.. Ti. (1973) Micaitop ut flyig peaseeili. Am. J. Par 1. The histor oa 1900. An. J. Opum. '3:35.33.

Pan11. The mblibu frumivisna Am. J. Open. 23:113-146-Oplohai. 76:.832-641. Pean i. Exww iea mam -lma an.,ei reaais. Am. J Opium. 28:173.2112

Paredee. D. and Jlim. B. (1967) gxwmaA5 of PEaUUfs &$oa am to 'ac'ia Welmveo. F.C. (1"571 A discussion of sawmaa rtinal coftapondence. Am;. or-subilimed oionm. J. Opt. Soc. Am. 37:8194330. to.171215

Flom M.. (9M o H-A..J.at l (iki Viiono(Cddm. Cdir Bok C. - Wick. B. (1974) Visual ikerapy for comam excuopia wad anomalous retinal cor-Flom. M.C ad Kerr. LIE. (1967) 04amaoo of rub correspoedence. Arch. - a case- 5 mpme. Am. J. Opium. Plarsuol. Opt. 51:1005.10011.

Ophahmal 7 200213.Wick. 8. (1975) *orced elsauuaoe of anoalousan reluasi correapondence in coam-Olaia .. (172)UmnlrAmals:Pa~aam1 aimmrp M213. tans eactapas - a came report. AM. J. Opium. ftysiol. Opt. 52:53-.62Profeassia Prie. loc. pp. 242.245.

Halle. U. (1962 Sepposm maamn e wam wia amomal AUTHOR'S ADDRESS:anomleu -, posi. Acm. Ophlmoel. 0082- P.O. Box 577

Haelversn U.M. and Yam Noardi. G.K. (1967) Micoroam a niewly fnmd em-N Arch O elamd 78:228. Fot Rucker. AL 36362-5292

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