Unusual location of intracranial vagus neurinoma--case report.

A 55-year-old male presented with hearing disturbance and tinnitus in the left ear. Computed tomography (CT) and magnetic resonance imaging demonstrated a well-defined, homogeneously enhanced mass in the left cerebellomedullary cistern without extension close to the jugular foramen. A three-dimensional image reconstructed from thin-slice CT scans demonstrated that the mass was clearly separated from the jugular foramen. The mass lesion was totally removed surgically. At surgery the tumor was found to originate from one rootlet of the vagal nerve just after its exit from the medulla oblongata. The histological diagnosis was neurinoma. Intracranial neurinomas of the glossopharyngeal, vagal, or accessory nerve usually originate within or close to the jugular foramen. This unusual location made it difficult to achieve a correct preoperative diagnosis.