Giant middle cerebral artery aneurysm with parent artery occlusion--case report.

A 54-year-old female was admitted with consciousness disturbance and right hemiparesis. Computed tomographic (CT) scans and angiograms revealed diffuse subarachnoid hemorrhage, a partially thrombosed, giant middle cerebral artery aneurysm (5 x 5 x 4 cm), and occlusion of the parent artery at the aneurysm site. Despite conservative treatment, a generalized convulsion occurred. Emergency CT scans revealed irregular enlargement of the left temporal high-density mass and severe mass effect due to cerebral infarction. Barbiturate coma therapy was administered, but she did not recover and died 9 days after admission. Only two cases of ruptured aneurysm with simultaneous occlusion of the major cerebral vessels have been reported, both with poor outcome. In this case, the mechanism of parent artery occlusion is unclear, but thrombus protrusion from the giant aneurysm into the parent artery may have been involved.