Acoustic schwannoma presenting as subarachnoid hemorrhage due to ruptured contact aneurysm.

The authors report a rare combination of aneurysm and acoustic schwannoma in a 66-year-old housewife, who developed subarachnoid hemorrhage from a ruptured aneurysm arising from an arterial branch of the posterior inferior cerebellar artery on the tumor capsule. Association of aneurysm and cerebellopontine angle schwannoma is extremely rare, and there has been no report of subarachnoid hemorrhage due to ruptured contact aneurysm, although previous reports indicated a small number of acoustic schwannomas accompanying hematomas in and around tumors.