ABSTRACT
We studied 56 patients, 30 women and 26 men ranging from 30 to 79 years of age (average age 64.5 +/- 10.4), who were admitted to our hospital between 1982 and August 1995 with clinical features compatible with occlusion at the level of the bifurcation of the basilar artery. The patients were selected following clinical and neuro-radiological criteria. All patients included in the study had two or more recent infarcts in the vertebro-basilar territory, related to involvement of the rostral region of the basilar artery. The diagnosis was confirmed by CT or MR scanning. The infarcts were in the thalamus, brain-stem, cerebellum and parieto-occipital lobe. A thalamic infarct associated with an infarct in another region was the most frequent lesion. The CT-MR findings in the 56 cases were: 29 patients presented with a unilateral thalamic infarct associated with another infarct (23 occipital, 8 parietal, 6 brain-stem and 2 cerebellum). There were eight patients with bilateral thalamic infarcts and seven with bilateral occipital infarcts. In six patients the occipital infarct was associated with another infarct at a different level (parietal or cerebellar) and six patients had cerebellar infarcts together with an infarct of the mid-brain. In 22 of the patients, lesions were found in three or more areas. The commonest clinical findings were: Motor deficit (69.6%), abnormal eye movements (44.5%), cerebellar dysfunction (42.8%), altered level of consciousness (32.1%), visual field defects (28.5%), pupil anomalies (19.6%). The most frequently associated risk factors were: Arterial hypertension (58.9%), a history of ACV (32.1%) and atrial fibrillation (21.4%). Mortality was 5.7%. In contrast to the classical descriptions, motor defecit was the commonest symptom in our series.