[Giant thrombosed fusiform aneurysm at the branch of the middle cerebral artery presenting with intramural hemorrhage: a case report].

We report a rare case of a giant thrombosed fusiform aneurysm at the branch of left middle cerebral artery presenting with intramural hemorrhage of the aneurysm. A twenty-year-old man with familial and past history of migraine presented sudden temporalgia on August 13, 1995. Computed tomography (CT) scan on the day of the first attack revealed a well delineated high density area at the left Sylvian fissure, 2.5cm in diameter. Angiogram showed avascular area corresponding to the lesion, but no visualization of the aneurysm. On October 18, this patient presented sudden temporalgia again. CT scan on the day of the second attack indicated new intramural hemorrhage and surgery was performed on October 31. No evidence of subarachnoid hemorrhage was shown during the operation, and the lesion was proven to be a thrombosed fusiform aneurysm at the branch of the middle cerebral artery. The parent artery was clipped at both proximal and distal sides of the aneurysm, and the aneurysm was totally removed with success. Histological finding further supported the idea that the attacks mentioned were due to intramural hemorrhage of the thrombosed aneurysm. Postoperative course was uneventful and the patient was discharged without any neurological deficit. Intramural hemorrhage of a giant fusiform aneurysm is relatively rare, only reported in several autopsy cases. Furthermore, we failed to discover any comparable cases of giant fusiform aneurysm presenting symptoms directly caused by intramural hemorrhage of the aneurysm.