Ruptured distal anterior cerebral artery aneurysms presenting as acute subdural hematoma--report of three cases.

The authors report three cases of distal anterior cerebral artery aneurysm presenting as acute subdural hematoma (SDH). Two patients were comatose on admission and died of massive SDH. One patient underwent aneurysmal neck clipping in the chronic stage and returned to normal daily life. A convexity SDH continuous with a wedge-shaped interhemispheric SDH was the characteristic computed tomographic appearance in all cases. There was no accompanying subarachnoid or intracerebral hemorrhage in one case (pure SDH). These cases are 9.4% of 32 ruptured distal ACA aneurysms treated in our institute in the last 14 years, a higher incidence than reported previously.