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When the Left Brain Is Not Right the Right Brain May Be Left: Report of Personal Experience of Occipital Hemianopia

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When the Left Brain Is Not Right the Right Brain May Be Left: Report of Personal Experience of Occipital Hemianopia J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.2.169 on 1 August 1999. Downloaded from J Neurol Neurosurg Psychiatry 1999;67:169–173 169 When the left brain is not right the right brain may be left: report of personal experience of occipital hemianopia Monroe Cole Abstract On the second day I became aware of visual Objectives—To make a personal report of hallucinations. These were especially promi- a hemianopia due to an occipital infarct, nent between 3 January and 10 January. (They sustained by a professor of neurology. are, however, not entirely gone after 2 years and Methods—Verbatim observation of neuro- appear to be fixed.) logical phenomena recorded during the My wife suggested, and continually encour- acute illness. aged me, not to miss the opportunity to record Results—Hemianopia, visual hallucina- my observations. tions, and non-occipital deficits without At first, virtually all of the hallucinations extraoccipital lesions on MRI, are de- were in bright colours, but some days they were scribed and discussed. in muted grey, brown, or yellow. These duller Conclusions—Hemianopia, due to an oc- colours would usually appear as swirling cipital infarct, without alexia, is not a dis- drapes, always in the right visual field, but ability which precludes a normal tending to interfere with vision in general. Only professional career. Neurorehabilitation twice did I see objects in black and white. has not been necessary. Sometimes the colour was not quite appropri- (J Neurol Neurosurg Psychiatry 1999;67:169–173) ate. Often there was a pony with his head cra- Keywords: occipital; hemianopia; visual hallucinations. dled in my right arm. I recognised the pony as the one owned by my granddaughter, but the colour was wrong. Personal reports of illness, disability, and the Most of the hallucinatory material was experience of being a patient, recorded by a recognisable but, as in the example above, the trained observer, are of use to the medical pro- colours did not always fit the object. I saw many fession. None of us plan to make such personal horses, dogs, and an even greater number of observations, but once the opportunity arises people, most of whom I could recognise. They advantage should be taken of it. moved, danced and swirled, but their purpose I am a right handed neurologist who under- was unclear. The hallucinations were neither went an aortic valve replacement with a St Jude horrendous nor frightening. Many hallucina- valve, as well as a double coronary artery tions were annoying even though I realised that bypass graft, on 2 January 1997 when aged 63. they were unreal. One hallucination often http://jnnp.bmj.com/ A self performed neurological examination in recurred. There would be a hand thrust out the recovery room disclosed a right hemiano- towards me; it would get larger, become pia. Brain MRI and neurological examination distorted, and then shake in a stereotyped (fig 1 and fig 2) demonstrated only a left manner either in the horizontal or sometimes occipital infarct on both banks of the calcarine in the vertical plane. Although the hallucina- fissure and the dense right hemianopia. tions interfered with vision, even at their worst Department of Neurology, Case on September 24, 2021 by guest. Protected copyright. Western Reserve University and University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, OH 44106–5000, USA M Cole Correspondence to: Dr Monroe Cole, Department of Neurology, Case Western Reserve University and University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, OH 44106–5000, USA. Telephone 001 216 844 3769; fax 001 216 844 5066. Received 16 October 1998 and in final form 5 March 1999 Accepted 5 March 1999 Figure 1 Brain MRI. (A) Sagittal view. Note infarct on both banks of the calcarine fissure. (B) Horizontal view. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.2.169 on 1 August 1999. Downloaded from 170 Cole I could continue to do some visual tasks such as the right visual field, noted mostly inferiorly. shaving. These are not annoying but occasionally Hallucinations did not occur during sleep distract me while I am reading. and could be diVerentiated from dreams. Dur- Generally, I am unaware of my hemianopia ing dreams, visual images were bilateral—that unless I attend to it or strike things on my right is, not confined to the right visual field—and side. I may start a line of writing on the wrong movements were not stereotyped. line above if the left side of the line is blank, In contradistinction to the hemianopic since I may be unaware of writing on the right hallucinations described by Kölmel,1 my hallu- side of the line. cinations were (1) not motionless; (2) not col- On a few occasions illusions were noted. At ourless; (3) not smaller than normal; (4) and the end of my hospital bed there was a clamp not extinguished by eye movement. Finally, (5) which, when I first began looking at it, seemed my hallucinations were virtually continuous to be a telescope on a military gunsight. After I during the first few weeks. saw what this actually was, I never had this On several occasions I saw what seemed to problem again. Much more unusual were be a fortification outline. Unlike my migrain- several episodes of false perception of colour. ous fortification scotomata, however, this did On one such occasion I painted an outdoor not move across the visual field but stayed in chair white. A few weeks later the house was one spot until it disappeared. Furthermore, the professionally stained white, and a deck was edges of the scotomata did not twirl or glisten, stained battleship grey. I looked at the chair, as my migrainous scotomata always do. which was some distance from the house, and Certain factors made the hallucinations wondered to myself why the painters had both- worse, such as tachycardia, increased heart ered to repaint my chair the same grey. I walked failure, or an arrhythmia requiring electro- over to inspect it carefully and found that it was as white as the day I painted it. conversion—which occurred five times post- I never read throughout my stay in operatively. During at least some of these hospital—the first time I ever remember episodes—for example, after cardioversion— I passing time without reading. In fact, I noted, was seen to be mildly confused. The hallucina- as did observant visitors, that I usually kept my tions were more prominent as the day went on eyes closed. I found vision bothersome al- and normally worse when I was taken to an though I never had diplopia. The exact quality unfamiliar environment. which bothered me is diYcult to analyse. I On discharge, while being driven home, I simply found it uncomfortable to see. After was constantly surprised by tall, hallucinatory discharge I was constantly encouraged to read objects along the right side of the road. Some- and was given a novel with large print. My times they would be on the right side of a bend enjoyment of reading was limited but rapidly in the road, causing me to wonder if the road improved, so that after the first book was com- were blocked. The further the car went, pleted I began to read for real pleasure. Medi- however, the more certain I became that our cal literature came rapidly thereafter. I had dif- progress would not be impeded. These halluci- ficulty reading in a moving car, mainly because nations were stereotyped: large tan or cream I would lose the line in which I was reading, but coloured buildings reminding me of old public after some weeks I could and would read con- http://jnnp.bmj.com/ buildings or churches one would see driving in stantly in a car. Italy. Such hallucinations persist, but only occasionally, and are very brief and evanescent. A further peculiarity of these roadside hallu- Discussion cinations are that they have only occurred while Hemianopic hallucinations occur in about an I am heading east, as they did when I first was eighth of hemianopic patients.1 driven home from the hospital. I have never In some patients the hemianopic hallucina- been aware of them while I am heading west— tions occur at the onset of the ictus—for exam- on September 24, 2021 by guest. Protected copyright. that is, away from home. Other hallucinatory ple, case 8 of Lance2—but usually there is a phenomena persist, especially diagonal lines in latent period before onset. Most hallucinations Figure 2 Visual fields by Goldmann perimetry. A. od 3 May 1997; B. os 3 May 1997. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.2.169 on 1 August 1999. Downloaded from When the left brain is not right the right brain may be left 171 consist of familiar people, animals, or objects; Consider, for example, some of the research on some have no obvious familiarity. Lance2 states macular sparing or splitting. Holmes11 14 that hallucinations consist of people and things showed that the central 10° of the visual field is rather than landscapes and scenes. projected to the most posterior part of the stri- ate cortex, including that part of the posterola- 7 WHERE IN THE BRAIN ARE HEMIANOPIC teral occipital tip. Cogan indicated that macu- HALLUCINATIONS ORGANISED? lar sparing is more common with parietal or They obviously do not arise from destroyed parieto-occipital lesions and less common with visual cortex. I would predict that they arise temporal or occipital lesions. He also states that from remaining visual cortex or, more likely, macular sparing is absent with “paracentral from extrastriate cortex.3 Manford and scotomas from lesions in the occipital pole.” Andermann4 have recently reviewed various But cases 14, 15, and 19 of Holmes and Lister10 putative mechanisms of visual hallucinations.
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