Acoustic neurinoma presenting as subarachnoid hemorrhage.

A 49-year-old man who had been suffering from disturbance of hearing for 5 years suddenly developed severe headache, nausea, and vomiting. Computed tomography (CT) scans both with and without contrast medium enhancement, performed on the day of admission, showed a nearly round high-density area in the left cerebellopontine angle. A left transaxillary vertebral angiogram showed no aneurysm or arteriovenous malformation. Hemorrhage from a tumor in the left cerebellopontine angle was suspected. CT scan without contrast medium enhancement, performed on the 17th day after onset, showed only a small, ill-defined high-density area in the cerebellopontine angle. An operation was performed on the 20th day after onset. The tumor was totally extirpated together with a clot. Histologically the tumor was an acoustic neurinoma with hemorrhage and necrosis. The postoperative course was favorable. Massive hemorrhage from primary intracranial tumors, especially acoustic neurinomas, is discussed. Radical operation on the tumor should be performed as soon as possible.