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 ■^|!IW^^^'!^*l«W*WllW^^ii»wpi^PipiP 
 
 (i^Apiimms OF 
 
 ^*W, Stirling M.B.J|a,j 
 ii&6 Mountain StJ 
 
 LIMITATIONS 
 
 OF THE 
 
 VISUAL FIELD OF INTRACRANIAL ORIGIN. 
 
 BY 
 
 J. W. STIELING, M.D., &o., 
 Surgeon Ocnlist and Auriat to the Montreal Dispensary and to the Foundling 
 
 Hospit-vl. 
 
 Repnnted from the Montreal Medical Journal, November, 1896. 
 
 • ' • ' ■ ■ V > 
 
 
 
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 ••• • •• '^ 
 
 
m§ 
 
 ^'■•■ri^-ii ' 
 
 LIMITATIONS 
 
 OF THE 
 
 VISUAL FIELD OF INTRACRANIAL ORIGIN." 
 
 UY 
 
 J. W. SriHMNd, M.B., &f., 
 SurRcon Oculist and Auiist to the Montreal Dispensary and to the FoundlinK 
 
 Hospital. 
 
 In natling tliis paper to you thi8 evening', I do not offer you any- 
 thing very new or original, b;it simply will give a precis of some 
 interesting cases and the pre; > aed or defined lesion in the brain 
 which caused the limitation of i jtr visual field. 
 
 I will take the liberty before ^oing into the subject matter proper, 
 
 Fio 6 
 
 4' 
 
 Cocrosied tract - 
 Corpora quadrigemins^ 
 
 rarieto-occl|)ita1 fissure 
 fW (i. e iv"^ .'i < ... Cuiieui.---- 
 
 C'alcuriQ« SMure 
 
 yf'y^'M Bitemal geDiculal* body 
 
 "^ ' iDleroal geniculate bodjT 
 
 Optic radiations, cj ^Y^^'t-ijlf} 
 
 Poeterior boroof lateral tenirlcl*. 
 
 of drawing your ettention briefly to the present status of our knowl- 
 edge as to the anatomy, both gross and minute, of the visual tracts 
 and their central connections in the brain 
 
 The fields of vision are, as you know, dividetl into an inner and 
 1 Read before the Montreal Medico-ChirurKlcal Society, October 30, 1896. 
 
 55147 
 
outer, or nasal and ternpoml portions — the divirlinrj line being fairly 
 sluirply defined and passing vertically through the fixation point. The 
 nerve fibres from the retina are united in tlu' optic nerve as far as the 
 chiasnia, where the tibres from the nasal portion of the retina decus- 
 sate with the corresponding fibres from the opposite eye. 
 
 Before following them farther, it is as well to (h'avv attention to the 
 fact that, as a gen(!ral rule, the ficM for a short distance on each side 
 of the lini! dividing the nasal and temporal portions of it, is innervated 
 with l)oth sets of fibi-es, so that in a case of hemianopsia, the blind 
 area limit would be clear of the fixation point. 
 
 From the chiasma the fibres fx'om the corresponding halves of the 
 retina pass through the optic tract to the basal ophthalmic ganglia, 
 viz., the pulvinar of the optic thalamus, the external geniculate body 
 and the anterior corpus quadrigeminum. 
 
 From the antex'ior co"nus quadrigeminum fibres run to the nuclei 
 (>" the ocular muscles — others decussate with tibres from the opposite 
 corpus (juadi-igeminum in the roof of the aqueduct of Sylvius and 
 thence pass to tb.e fillet whicli runs on in the tegmentum of the 
 cerebi-al peduncle to the optic thalamus. 
 
 The fillet contains the sensory fibres from the opposite half of the 
 body. 
 
 From the arm of the anterior corpus quadrigeminum fibres go to the 
 corona radiata and so on to the occipital cortex in the region of the 
 cuneus where the centres for vision lie. 
 
 From the pulvinar and extei'nal geniculate bodies, fibres enter 
 Gratiolets optic radiations (or corona radiata) in the posterior third of 
 the internal capsule between the lenticular nucleus and optic thalamus 
 and thus run on to the occipital cortex. 
 
 The external geniculate bodies receive mainly the fibres from the 
 macula of each eye, according to Knies. 
 
 In the chiasma in addition to the optic nerve fibres are two bundles 
 of fibres lying posteriorly and superiorly called respectively Guddens 
 and Meynerts Commissures. 
 
 Gudden's commissure connects both posterior corpora quadrigemina 
 and internal geniculate bodies and sends fibres directly into the 
 corona radiata of the occipital lobe on the same side. 
 
 This commissure seems to have no connection with vision, but 
 rather to act as an auditory chiasm. 
 
 Each convolution of the cerebrum is connected with adjacent con- 
 volutions by association fibres, as is also each lobe of the same hemis- 
 phere — and also homonymous ])arts of each hemisphere by commis- 
 sural fibres. Hence the different portious of the brain are intimately 
 connected. • 
 
3 
 
 Ajfain tlio centrifuf^'al and ct'iitripctal connection of the cortex with 
 the rest of the brain is hy tlic corona radiata in which the fibres are 
 collected in the internal capsule. 
 
 Of tlie association fibres, one of the most important bundles is 
 that connectiiif,' the visual cortex with Broca's frontal convolution, on 
 account of the hitter's relation to speech. 
 
 A point that Knies brings out is the presence of centripetal and 
 centrifugal fibres in the optic nerve, the former being much finer than 
 the latter and originating in the gangliop layer of the retina, to ter- 
 minate in a fine piexus in the optic basal ganglia. 'J'he centrifugal 
 originate in the ganglion cells of the three liusai optic nuclei, are 
 coarser and come to an end in the internal granular layer of the 
 retina. 
 
 As to the connection of the optic tracts with the pupillary nucleus, 
 it is a question wluither the fibres from the tracts pass through the 
 anterior corpora (]uadrigeniina oi- extei-nal "geniculate body and pul- 
 vinar or whether they pass from the tract close to these bodies directly 
 to the ganglion habenuhe. 
 
 A word as to the location of the cortical visual centres. The macula 
 portion of the field corresponds to the cuneus and first occipital con- 
 volution. Of the rest, of the occipital cortex, the anterior portion 
 corresponds to the lower portion of tlie Held of vision, the posterior to 
 the upper portion, and the lateral to the outer portion. 
 
 The first case I will mention is, J. W. McK., aged 29. I saw him in 
 October, 1895. Nine months previously, he was troubled with severe 
 headaches and vomitincj. Three months later he had an attack of 
 
 Jack.sonian epilepsy for the first time, which after this frequently 
 recurred. 
 
 In tho^e attacks the left arm was drawn up over the head, the left 
 leo- was drawn up flexed, the head was di'awn back and to the left 
 and the eyes rolled up and to the left. 
 
Vision had been failing latterly. His c-onditiou on OctoluT 7tli, 
 when 1 tii'st saw liini was as follows: — 
 
 Complete left heniiplegia. 
 
 Vision L. E., ^'a- 
 " R.E.,t 
 
 Both pupils active to light and accon.modation, also consensnally, 
 also on stimulating the blind retinal ari'a. 
 
 There was left hemianopsia, the dividing line elearing the fixation 
 point. The I'ight sides of both fields were slightly contracted, but 
 the colour vision field, although contracted, was normal as to perception 
 
 of colours. 
 
 In both fundi one saw (edematous choked discs, the surrounding 
 retina being only slightly swollen, and there being no luBmorrhages. 
 The visible disease was most advanced in the left papilla. Mentition 
 and speech were slow. The patient died six weeks later, a post-mortem 
 was performed Viy the local medical man in the country, and the 
 report was not very explicit, being merely that he found a tumour in 
 the motor area of the right cortex and neighbourliood. : 
 
 The case presents a most interesting clinical picture. 
 
 The iii'itative symptoms of the Jacksonian epilepsy clearly would 
 point to the seat of the lesion as being in the right motor area, yet 
 this could not be absolutely affirmed, since the distant symptoms of 
 a cerebral tumour are .so varied. , l 
 
 The later development, however, of the marked paralytic symptoms 
 on the opposite half the body pretty well removed any possible doubt 
 The further appearance of left hemianopsia with retained pupillary 
 reflex would point to a lesion posterior to the basal optic nuclei, either 
 in Gratiolet's radiations or the cerebral occi[)ital cortex. 
 
 I may here mention that this pupillary reaction from stimulation 
 of the blind area of the retina in these cases I never feel absolutely 
 sure of, if the reflex is present— as the test is delicate — more certainty 
 can be felt if it is absent ; the latter pointing to a lesion at or in front 
 of the basal optic nuclei. 
 
 The growth must also thus implicate the visual cortex on the right 
 side directly either in the cortical centre or the radiations, likely 
 the former. 
 
 It would hardly be in the radiations without causing other paralyses 
 of ordinary sensation — hemianaesthesia. 
 
 The contracted fields on the right side must be ascribed to tlie 
 choked disc condition, with the accompanying interference of conduc- 
 tion in the nerve — although the diminution in vision is far from being 
 constantly present in choked disc. 
 
Tli(! Hjipeuranco of tlu; disca was rather that of (L-denuitoiis infiltra- 
 tion than an inflammatory prcjcess. 
 
 Knies explains tliis condition as due to increased intracranial 
 pressure. 
 
 He says that normally there is an outflow from the oye towards the 
 hrain within hoth the nerve and its sheaths. Increaseil intracranial 
 pressure would aholish this ; .stasis ami oedema woukl develop. 
 
 This o'deuia heconuis evident in the optic nerve outside the cranial 
 cavity, where it is not enclo.sed in a tightly fitting .sheath, i.e., at the 
 •disc, and also within the vaginal s])ace.s where the external sheath is 
 thinnest and yielding; immediately liehind the eye. 
 
 Persistence and increase of this pressure on the nerve can in time 
 obstruct visi(m. Now as to the movements of the eyes up an<l to the 
 left, this symptom occurring early, during the Jack.sonian epilep.sy 
 could be due to the irritation of the visual splieres, taking into account 
 the later appearance of the left hemianopsia. Although one need not 
 look so far afield as thi.s, for it is well-kncwn that conjugate deviation 
 towards the opposite side can be called forth on irritation of almost 
 all parts of the ctu'ebral cortex. 
 
 Yet it is most surely done by stimulating the visual cerebral cortex, 
 Munk showed that irritation of the anterior zone caused the eyes to 
 be directed downwards and of the posterior zone to be directed 
 upwards as well as to the opposite side 
 
 Thus the clinical picture pointed very clearly to what we might 
 expect to find at the post-mortem examination. 
 
 The next case 1 will describe to you also came to section so that the 
 diagnosis could be verified ; it has already been reported by Dr. James 
 Stewart. 
 
 It is very interesting in this connection in that the lesion was situ- 
 ated in an entirely different portion of the visual tract from the last. 
 J. W., aged 42, came to me in February, 1888, with total blindness 
 of the left eye and complete right hemianopsia of the right eye. The 
 left eye had been failing since two years, and the right for eighteen 
 months, but the latter had remained apparently stationary since eight 
 months. 
 
 He had pains in joints and hands ; there is some giddiness with a 
 tendency to fall forward : no history of syphilis. 
 
 Has been a rather heavy drinker. Vision L. E., no perception of 
 light, pupil semidilated immobile, but reacts on stimulating the R E. 
 with light. 
 
 P.. E., complete blindness to outer side of field, the inner side was 
 amblyopic; vision being reduced to counting fingers at 12 ft. In 
 
6 
 
 rcadinf,' type can pick out a letter of the l»r;^'est .size (No. Kiyhereand 
 
 tliere. In tlii.s area fclie perception of <,'reen wa.H v(;ry defective, also 
 
 after looking at green for sonu; time there wa.s an afterimage h\ pink- 
 Examination of the fundu.s revealed, in the L. VI. white atnjphy of 
 
 the disc, with ve.s,sel.s .somewhat contracted. 
 R. E. disc tiot ,so pale as in left eye. 
 Hi.s rellexes were .slightly exaggerated, hut there were no motor 
 
 di.sturhances. 
 
 Frequent Hushing.s and pisrspiration of face and hack of neck 
 
 occurred. 
 
 The further course of this ca.so was very slow, six years elapsing 
 
 before his death. 
 
 \ 
 
 TYV 
 
 360 
 
 330' 
 
 H'vi sight entirely failed about eighteen months after I saw him. 
 He became fat and flabby, always had a good appetite, but was greatly 
 bothered with continuous sleepiness. 
 
 Frequent flashings of light (Photopsia;) appeared, and later on he 
 developed hallucinations of "beasties" crawling over him, which he 
 imagined he could point out. The post-mortem examination revealed 
 a tumour as large as a hen's egg, springing from the meninges and 
 pressing on the front of the chiasma. 
 
 The microscopic investigation showed the growth to be of the 
 nature of an endothelioma. 
 
 The diagnosis made at the first time Dr. Stewart and I saw him 
 was that of cerebral tumour, implicating the chiasma from the front. 
 
 The visual disturbance was the only factor to base the diagnosis on, 
 and if one could only liave seen the patient earlier the limitation of 
 the field would have been more typical. 
 
 The absence of the pupillary reflex showed that the lesion muSt be 
 somewhere between the left eye and the basal optic nuclei, also the 
 presence of visible optic atrophy was, if necessary, a proof against the 
 lesion being further back than the basal nuclei, as in lesions of the 
 
\ 
 
 optic radiation.s or cortex, whiti' essential atrophy is exceedingly 
 rarely, if over visible at the optic disc. 
 
 Again and mainly, it would lie hardly possible to have a lesion 
 causing bitemporal hemianopsia anywhere else than in the anterior 
 part of the chiasma, uidoss we could imagine a lesion of each ci-ntral 
 nasal area. The portions of tlu; optic ncsrve supplying the inner 
 halves of the retina decussate in the anterior part ot the chiasma, a 
 furtlier extension of the growth to the left would easily oliliterate the 
 function oi the remaining portion of the left optic nerve causing 
 complete blindness of that eye an*l subsequent atroj)liy. 
 
 When I first saw the patient the obtunding of the nasal half of the 
 right field, together witn the defective perception of green, pointed to 
 marked interference with the conduction of the remaining active por- 
 tion of this nerve; there was a concentric and faiily e([ual contraction 
 of the field for white and colours pointing to a likely slow growth ; if 
 on the otlier hand the field for colours had Iteen much more markedly 
 contracted for colours than for w hite, the prognosis would be a rapid 
 progress of the disease. 
 
 Another striking point was the absence of any optic neuritis or 
 choked disc. 
 
 It is likely the very slow growth of the tumour would account for 
 the absence of the choked disc, time lieing sufficicmt to allow of the , 
 formation of lateral drainage or gradual distension of the sheath. 
 
 The hallucinations point t(j the cortex being still functional (it 
 being the seat of conscious vision) and to its irritation. 
 
 Another interesting case in whif^U the visual distui'bance was due, 
 not dii-ectly to the intracranial lesion, but to the optic neuritis set up 
 by it, is the following : 
 
 G. J., aged 12, was referred to me by T Springle for examination 
 of the ocular condition. 
 
 He had for some weeks been suffering from severe headaches, 
 occasional vomiting and giddiness. 
 
 His vision was yV with each eye, but no lens could further improve it. 
 
 The pupils reacted to light but wore sluggish, they were even. 
 
 The field was slightly contracted peripherally, and the perception 
 of green uncertain 
 
 The fundus showed marked inflammatory choked disc, with great 
 swelling (3 nun.) extending well into the surrounding retina and 
 numerous small hsemorrhagcs. The condition was if anything more 
 marked in the right. 
 
 The boy complained of the headaches being general, and continuous 
 
8 
 
 with occasional exacerbations. He was markedly gidd}', with a ten- 
 dency to fall t'orwai'd, a very unsteady reeling gait, knee reflexes 
 exaggerated, but no other motor or sensory disturbance. 
 
 This cas3 got rapidly worse, complete blindness ensued within four 
 weeks, convulsions, general in character, set in which became almost 
 continuous, and finally coma and death. 
 
 I am able to show you the brain. At the post- mortem examination 
 wc found almost the entire vermifonn process of the cerebellum occu- 
 pied by a tumour which had undergone softening at its centre; it wag 
 strictly limited to the vermiform process and the immediately adjoin- 
 ing cerebellum. 
 
 The main localizing symptom here was the verti£0. The cerebellar 
 coordination and integration of the body movements being interfered 
 with ; the direct cerebellar tracts which convey to the cerebellum, 
 sensory impressions indicatirg the posture of the body, being partly 
 destroyed. The infiamma+jry nature of the choked disc differed 
 entirely from the oedematous form I menti(med as recurring in my 
 firdt case of cerebral tumour. 
 
 According to Leber and othei-s, tumours especially of the cerebellum 
 and base, if rapidly growing, excrete irritating and inflammatory 
 substances. These are diffused through the cerebro spinal fluid and 
 enter the sheath of the optic nerve, where from increased intracranial 
 pressure stasis has already existed and here where oidema has devel- 
 oped, the substances set up inflammatory action. 
 
 The narrowing of the field, together with the faulty perception of 
 green is typical of interference With conduction in the nerve. 
 
 The diagnostic value of the double optic neuritis in cerebral tumours 
 is well known. 
 
 The next case is one nf hemianopsia and hemiplegia due, I think, to 
 embolism or thrombosis. 
 
 T. H.; aged 68, a diabetic, came to me last autumn for the examina- 
 tion of his eyes for ghuses. He was suttering from right hemiplegia 
 and stated that some months previously he had a paralytic stroke. 
 After this he v^as for a short time aphasic but this symptom gradu- 
 ally disappeared. 
 
 On examining his eyes I found, in addition to some opacities of the 
 lens, well marked right homonymous hemianopsia, and this was the 
 mam cause of his complaint, on account of the difficulty in reading, 
 thfc inaViility to see words ahead on the line being very troublesome. 
 
 The pupils were even and active, on stimulating both the blind and 
 normal portions ',;f the field. 
 
 Seven months later the general condition was the same. 
 
' I 
 
 There was no hemianesthesia at any time. 
 
 There is some difficulty in locating this lesion as the areas art'ected 
 are so diverse. 
 
 In the ocular symptoms the presence of the pupillary rea^-tion point 
 to the lesion being somewhere behind the basal optic nuclei on the 
 left Side, either in Gratiolet's optic radiations in the internal capsule 
 or in the cortex. 
 
 It is unlikely to have been in the former as there was no 
 anessthesia, and the fibres of general sensation run in the same portion 
 of the internal capsule— while still further in front are the motor 
 fibre.s. Now these latter and the special sense optic fibres could 
 hardly be affected in this region, while the fibres of ordinary sensa- 
 tion escaped. Hence the lesion must be cortical, and could hardly be 
 otherwise than thrombotic or embolic in the middle cerebral artery. 
 
 The aphasia vas a transitory, remote symptom. 
 
 According to Seguin, a lesion causing typical hemiplegia, aphasia if 
 the right side is paralysed, little or no anesthesia, and lateral 
 hemianopsia is probably due to disease in the area supplied by the 
 middle cerebral artery. 
 
 An exceedingly interesting and rather peculiar case of colour blind- 
 ness in homonymus halves of the field of vision came under my 
 observation some years since. 
 
 J. K., aged 35, suffering from incipient general paralysis of the 
 insane was referred to me by Dr. James Stewart. 
 
 The vision was f , or approximately normal, the pupils even and 
 active and the Helds free foi- white but total colour blindness existed 
 to the left side of both fields of vision. 
 
 He had left facial paresis. Beyond this and tlie mental cokdition 
 there was nothing to note. 
 
 With the reaction of the pupils present, the condition was plainly 
 referable to the right occipital cortex. 
 
10 
 
 An interesting point was the retention of such good central vision . 
 
 Wilbrand brought forward the theory some years since that the 
 elements for the perception of light, space and colour in the cortex 
 were superimposed above one another in the above order from within 
 cutward, hence the colour sense could be interfered with, without the 
 light or space sense being aftected, and again the light elements could 
 not be interfered with, without the space and colour elements also 
 suffering. Accordingly hemiachromatopsia would be due to super- 
 
 T 1^ 
 
 l£ 
 
 IcJl- Ji^t-^ * A A (t/iA. i^-^ L.rt-'/'-f^^*s-<' <* 
 
 
 ficial disturbances of the cortex. This I mentioned some years ago 
 in a paper I read in Ottawa. 
 
 As Knies, however, points out, anatomical proof of this is wanting 
 and he brings forward a far more sensible assumption, that the func- 
 tion in the cortex is merely disturbed or rendered difficult, interfer- 
 ence with conduction in tbo neiiropilemma or the ganglion cells 
 exhibit diminished function and capacity for action, which may be 
 temporary or remain statioaary. 
 
ma 
 
 11 
 
 Likely here we get a manifestation in this area of the general 
 pathological state whatever it may be, which is associated with the 
 general paralysis. 
 
 I have now brought before you a series of cases of visual disturb- 
 ance due to brain lesions, each of them fairly characteristic, and 
 happily in three cases, the post mortem reports were secured to com- 
 plete them. 
 
 The first of left hemiplegia and hemianopsia, with a tumour in the 
 right motor area and neighbourhood, producing oedematous choked disc 
 
 
 n. 
 
 %L 
 
 /^^,^^A/ 
 
 <,*,<a.<r-**/' O-t » t. 
 
 ^ CA 
 
 
 The second of tumour of very slow growth in the chiasma area with 
 typical field limitations and setting up pure atropy of the optic nerves. 
 
 The third case was the cerebellar tumour, setting up optic neuritis 
 and consequent blindness. 
 
 The fourth was 
 to thrombosis or 
 
 The fifth was the 
 
 jlindness. 
 
 as a case of JjAi}*H&'»iljp5iia'iu>d.hptujplegia, due likely 
 
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 the interestkig pas£.o{.l;emiai^lir6ftiato'^sitC.:.. 
 
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