[A case of acoustic neurinoma simulating subarachnoid hemorrhage (author's transl)].

A 49-year-old male, who had been suffering from left hearing disturbance before 5 years, suddenly developed severe headache, nausea and vomiting on January 3, 1979. Both plain and enhanced CT performed on the day of admission showed a nearly round high density area at the left cerebello-pontine angle. The left trans-axillary VAG showed no aneurysm or AVM. From the above-mentioned course and findings, hemorrhage from a tumor of the left c-p angle was suspected, but considering the size of the high density area, radical operation was considered to be contraindicated and v-p shunt operation was performed. However, plain CT performed on January 19th, showed only a small, ill-defined high density area at the c-p angle. The tumor was quite large, but considered to be operable, so that excision was performed on January 22nd. The tumor, 5 X 5 X 4 cm in size, was totally extirpated together with the clot. Histologically the tumor was acoustic neurinoma with hemorrhage and necrosis. Postoperative course was favorable. We discussed the massive hemorrhage from primary intracranial tumors, especially acoustic neurinoma. Radical operation on the tumor should be performed as early as possible, provided that the patient's condition permits.