"Top of the basilar" syndrome: a comparison of clinical and MR findings.

Among 100 patients with an infarction of the brain reported on MR and clinically confirmed there were 4 with widespread lesions of the temporal and occipital lobes, thalamus, midbrain, pons and cerebellum, all supplied by arteries originating around the top of the basilar artery. Clinically these patients presented the "top of the basilar" syndrome, which is caused by a disturbance in circulation at the top of the basilar artery. Which brain areas are involved may be deduced theoretically from the vascular anatomy. These lesions can, we believe, be clearly detected using MR, because of its sensitivity to ischaemic disturbances and in the posterior fossa. We report our 4 patients here to illustrate the clinical presentation and MR findings of the "top of the basilar" syndrome.