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Cerebral Achromatopsia As a Presentation of Trousseau's Syndrome

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Cerebral Achromatopsia As a Presentation of Trousseau's Syndrome 44 Orrell, James-Galton, Stevens, Rossor Postgrad Med J: first published as 10.1136/pgmj.71.831.44 on 1 January 1995. Downloaded from Cerebral achromatopsia as a presentation of Trousseau's syndrome Richard W Orrell, Merle James-Galton, John M Stevens, Martin N Rossor Summary four years previously, and had been taking A 67-year-old man developed a sudden 300 mg aspirin daily. onset of achromatopsia. Magnetic reson- On examination he appeared well, with a ance imaging showed occipital lobe regular pulse, blood pressure 160/100 mmHg infarction. Repeated episodes of neuro- normal heart sounds, and no carotid bruits. logical deficit referable to the posterior Neurological examination was normal, but for circulation initially suggested an embolic absent colour vision and a partial right source, but subsequently proved to be due hemianopia. Visual acuity was 6/18 bilaterally. to a coagulopathy related to a carcinoma Two weeks after the onset of visual distur- of the bladder. This has implications for bance he developed a sudden onset of upper the management of patients presenting motor neurone weakness in the right arm and with achromatopsia, and progressive or face, with reduced sensation in the right arm, recurrent neurological episodes, and in following a bout ofheavy coughing. Investiga- particular the use of anticoagulation in tion at this time demonstrated normal full this situation. blood count, erythrocyte sedimentation rate, prothrombin time, serum urea and electrolytes, Keywords: cerebral achromatopsia, Trousseau's syn- and glucose. Treponemal serology was drome, bladder carcinoma, disseminated intravascular negative. Chest radiograph was normal. Com- coagulation puted tomographic (CT) scan of the brain showed an area of presumed recent infarction Introduction involving the left occipital lobe and posterior part of the temporal lobe. Magnetic resonance 'Cerebral achromatopsia is a syndrome in (MR) scan the next day showed bilateral which the patient loses the ability to see colours occipital lobe infarction, mainly below the after cortical damage. This loss may be com- calcarine fissure (see figures). MR angiography plete or partial, and it may or may not be showed the posterior circulation to be normal, accompanied by other visual defects'."2 We with no evidence of basilar artery thrombosis. http://pmj.bmj.com/ describe a case of this unusual but readily Doppler examination of the carotid arteries recognisable clinical syndrome, and its associa- showed a 30% internal carotid stenosis on the tion with a paraneoplastic coagulopathy. right, and 55% on the left. There was no clinical or electrocardiographic evidence of an Case report arrhythmia, and an echocardiogram showed no evidence of a cardiac source of emboli. man was as a front seat on September 29, 2021 by guest. Protected copyright. St Mary's Hospital, A 67-year-old travelling Praed Street, London, passenger in a car when he experienced a UK sudden brilliant flash of white throughout his NEUROPSYCHOLOGICAL ASSESSMENT Department of vision, followed by a kaleidoscope effect, with A detailed neuropsychological assessment was Neurology criss-cross lines and bright colours. The carried out at the time of the original visual RW Orrell experience lasted about 20 seconds, and he was deficit. On the Wechsler Adult Intelligence MN Rossor with some of and was Scale (Revised) he obtained a verbal IQ of 128.3 Department of left fogginess vision, only Neuroradiology able to see images in black and white. Three There was no evidence of generalised intellec- JM Stevens weeks previously he had experienced an epi- tual impairment. Recognition memory for ver- sode of weakness in the right hand, lasting for bal material was excellent, he scored in the Department of two days, but otherwise had no previous superior range on the Warrington Recognition Clinical neurological symptoms. Over a period of two Memory for words.4 Neuropsychology, The weeks there was some in his Test of primary visual function were per- National Hospital, improvement Queen Square, vision, but persistence of the loss of colour formed. Reading acuity on the Ffookes sym- London, UK vision. bols test was 6/18. Shape discrimination was M James-Galton Eighteen months previously he had present- within normal limits.5 Shape detection on the ed with haematuria. Cystoscopy demonstrated VOSP (Visual Object and Space Perception) Correspondence to a multifocal transitional cell carcinoma on the figure-ground was unimpaired.6 Colour dis- Dr Richard W Orrell, Academic Unit of left wall of the bladder which was in the early crimination was severely impaired. He was Neuroscience, Charing Cross invasive stage. This was being controlled by unable to pick out any numbers on the Ishihara Hospital, Fulham Palace repeated cystoscopy and fulguration. He had test. He had great difficulty on the Farnsworth Road, London W6 8RF, UK ischaemic heart disease, with occasional 100-Hue test, error score 784.78 There was no Accepted 11 August 1994 angina, had coronary artery by-pass grafting evidence ofvisual disorientation; he was able to Cerebral achromatopsia 45 Postgrad Med J: first published as 10.1136/pgmj.71.831.44 on 1 January 1995. Downloaded from Figure 1 MRI, 1.5 Tesla, with Gadolinium enhance- ment, showing features ofbilateral occipital lobe infarc- marked on the left Figure 2 MRI, coronal section of the brain, showing tion, more features of bilateral occipital lobe infarction, mainly below the calcarine fissure count scattered dots accurately, missing only those which fell within his visual field defect. Tests of higher visual processing from the period of weeks had some recovery of vision in VOSP6 were performed. He was completely the left homonymous fields, but remained unable to see any form of a letter on the drowsy, and the heparin was discontinued. Incomplete Letter task. His performance on Within two weeks he developed a deep vein the Silhouettes test was very poor (4/30). On thrombosis of the right leg, with gangrenous the Progressive Silhouettes test he was slow to areas in the toes, and as there was some identify the objects even when complete. He recovery in his conscious level, heparin was also made errors of identification of simple line recommenced. Within three months of the drawings ofobjects. He showed some degree of initial presentation of visual disturbance he prosopagnosias, being able to identify only 1/12 developed significant haematuria, with further Famous Faces and he complained of difficulty evidence of disseminated intravascular coagu- in recognising people. lation (DIC). Over a period of one week the The interpretation ofhis neuropsychological coagulopathy progressed. This failed to re- http://pmj.bmj.com/ assessment is that the only elements of cortical spond to treatment with platelets and fresh blindness present were a severe achromatopsia frozen plasma and he died peacefully. and a mild impairment ofacuity. In addition he Post-mortem examination showed the cause had an aperceptive agnosia. The degree of of death to be a pulmonary embolus, with a impairment of his primary visual processing thrombosed right external iliac vein. There was was insufficient to account for his poor perfor- a stage 4 bladder carcinoma, invading through mance on tests of visual object processing. the bladder wall into the perivesical fat, with a on September 29, 2021 by guest. Protected copyright. right hydronephrosis and hydroureter. His- PROGRESS tology showed an ulcerated poorly differenti- In view of the recurrent episodes of neuro- ated transitional cell carcinoma extending into logical deficit, which were felt to be possibly the perivesicular fat, and lymphatic channel embolic, he was started on an infusion of invasion. There was no evidence of metastatic heparin at 10 000 units over 24 hours, with spread. On examining the brain, there were caution because of the haemorrhagic nature of bilateral basal occipital infarcts and bilateral the infarct, and his previous haematuria. The parietal infarcts, all being recent, with signs of right arm weakness resolved over three days, colliquative necrosis. Additional infarcts were with a residual mild right facial weakness. He present in the kidney and spleen, with gang- was commenced on warfarin anticoagulation renous infarction of the right forefoot and toes with careful control. of the left foot. There was no evidence of an Two weeks later, having developed mild embolic source in the heart or great vessels. haematuria and having discontinued the war- farin himself, he was found wandering at night, Discussion aphasic and agitated. He had a left upper motor facial weakness, and a progressive left hemi- Cerebral achromatopsia has been recognised plegia. He had complete cortical blindness, for many years, with debate over the existence with small pupils, absent gag reflex, and brisk of a specific cortical colour centre. Clinical jaw jerk. CT scan at this stage showed extensive evidence links the anterior inferior part of the bilateral occipital infarction. He was again occipital lobe with colour perception in man. commenced on a heparin infusion, and over a Bilateral lesions at this site may cause achroma- 46 Orrell, James-Galton, Stevens, Rossor topsia with preservation of primary visual function.9 A unilateral lesion will cause Impaired colour vision hemiachromatopsia. Animal studies, and more * achromatopsia = cannot see colour Postgrad Med J: first published as 10.1136/pgmj.71.831.44 on 1 January 1995. Downloaded from recently functional positron emission tomo- * agnosia
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