Cervical schwannoma presenting with acute intracranial subarachnoid hemorrhage.

A subarachnoid hemorrhage (SAH) associated with negative finding on four-vessel angiography is seen in 5 to 30% of patients with intracranial SAH. A previously silent lesion in the spinal canal may be responsible for the angiographically negative finding for cause of intracranial SAH. We report a case of upper cervical (C1-2) intradural schwannoma presenting with acute intracranial SAH. Repeated cerebral angiographic studies were negative, but cervical magnetic resonance imaging study and tissue pathology revealed a intradural-extramedullary schwannoma in C1-2 level. This case illustrates the importance of a high index of clinical suspicion for spinal disease in angiographically negative intracranial SAH patients.