No abstract

Single photon emission computed tomography assessments were conducted in normal controls (n = 25), patients with unilateral cerebellar infarctions (n = 4), patients with olivopontocerebellar atrophy (OPCA; n = 15) and patients with Friedreich’s ataxia (FA; n = 6). In subjects with unilateral cerebellar infarctions, crossed cerebellar-cortical diaschisis was observed: reduced cerebellar hexamethylpropyleneamine oxime (HMPAO) uptake was invariably accompanied by a diminution of HMPAO in the contralateral basal ganglia and frontoparietal cortex. OPCA and FA patients had various degrees of decreased HMPAO uptake in both the cerebellum and cerebral hemispheres.

A woman had a left superior cerebellar artery infarct associated with reduced hexamethylpropileneamine oxime uptake on SPECT scan of the basal ganglia and frontoparietal areas of the opposite hemisphere performed poorly in some neuropsychological tests indicating right hemisphere dysfunction. There was a lengthening of reaction and movement times with the hand ipsilateral to the lesion. These deficits were temporary. A unilateral cerebellar lesion can produce neuropsychological deficits, possibly because of hypoperfusion in contralateral frontoparietal regions, but spontaneous neuropsychological remissions may occur.Resume: Fonction neuropsychologique avec une lesion cerebelleuse unilaterale. II s'agit d'une patiente ayant eu un accident cerebro-vasculaire suite a une thrombose de I'artere cerebelleuse superieure el qui a presente une diaschisis cerebello-corticale a la scintitomographie (SPECT) avec hexamethylpropileneamine oxime (HMPAO). devaluation neuropsychologique a ete suggestive d'une dysfonction frontopari£tale droite, la meme localisation que celle de 1'hypoperfusion constatee au SPECT. Une lesion cerebelleuse unilaterale peut delerminer des deficits suggestifs d'une dysfonction neuropsychologique frontoparietale contralateral en presence d'un scan normal.Can. J. Neurol. Sci. 1994; 21: 353-357 The role of the human cerebellum in non-motor behavior is an emerging concept in full development. After our initial description of neuropsychological disorders determined by bilateral cerebellar lesions, 1 papers from our laboratory and elsewhere 2 " drew attention to the occurrence of specific neuropsychological deficits with bilateral cerebellar injury. In contrast, there are few reports 1214 of neuropsychological assessment in patients with unilateral cerebellar damage.Cerebello-cortical diaschisis has been detected by single photon emission computed tomography (SPECT):31516 after a unilateral cerebellar infarct, hexamefhylpropyleneamine oxime (HMPAO) hypoperfusion may be observed in the contralateral frontoparietal cortex despite a normal CT scan at the cortical level. 316The aim of this case report was two-fold: i) to evaluate neuropsychological performance in a patient with a very welldelimited cerebellar infarct; and ii) to assess if neuropsychological shortfalls, if any, correspond to a deficit usually considered to be induced by lesions of the cerebral hemisphere contralateral to the cerebellar insult.CASE REPORT L.P., a 64-year-old right-handed woman with 12 years of education, was treated for high blood pressure for 20 years. She was admitted to the Neurology Service for dizziness of sudden onset, nausea, vomiting and ataxia. Neurological examination revealed moderate gait ataxia and a moderate left-sided cerebellar syndrome documented by deficient finger-nose-finger and heel-to-knee tests as well as adiadochokinesia with the left hand. She had bilateral brisk tendon reflexes; her plantar reflexes were flexor. There were no other neurological abnormalities. After 2 days, the nausea and vo...