[Angiographical extravasation in the intracranial hemorrhage due to cerebrovascular moyamoya disease--autopsy study].

A 53-year-old, non-hypertensive farmer, who had sudden attack of severe headache, was transferred to our clinic. He presented comatous state and tetraparesis without extraocular movements nor reactive pupils to light. CT scan, 7 hours after the ictus showed intracerebral hematoma in the right temporo-parietal region with ventricular extension. The following bilateral carotid angiograms established the diagnosis of the intracerebral hemorrhage due to cerebrovascular moyamoya disease. In angiograms of the affected side, irregular spotty stains spread from the periphei of the right posterior choroidal artery was delineated. The repeated CT scan after that indicated increment of hematoma. Fifty-three hours from the ictus, the patient died and an autopsy study was performed. After the fixation, the coronal brain section was made, and the careful observation of them elucidated the formation of an organized dissecting aneurysm in the angiographically extravasated vessel. About seven hundreds of serial specimen, 4 micron in thickness, was then investigated adjacent to the aneurysm. The organized dissecting aneurysm seemed to initiate from the branch of it, where marked fraying and undulation of the fibroelastic intima and internal elastic laminae were observed. The concavity toward the true lumen was completely disrupted and communicated to the extravascular space. As a result, the continuous part of it obstructed the lumen of the branch. These findings suggested the newly-developed dissection and it seemed to correspond to the angiographical extravasated points.