Two cases of acute basilar artery occlusion, a 63-year-old male case and a 71-year-old female case were presented. The diagnosis of basilar artery occlusion was made by means of cerebral angiography and autopsy. The CT appearance within 24 hours after onset was an ill-defined decreased density of white matter of the occipital lobe and the cerebellum. The CT appearance beyond 24 hours after onset was a well-defined decreased density of the cerebellum and the occipital lobes, which was supplied by posterior cerebral arteries. Pontine lesion was not remarkable on the CT-image in our cases. Gross autopsy findings showed no remarkable lesion in the cerebellum and the occipital lobe in Case 2, who died 7 days after onset. Histologically, however, definite brain edema detected in these brain regions.
