[Case of meningioma with extracranial extension through the internal jugular vein].

We report a case of posterior fossa meningioma extending into the cervical jugular vein, which was successfully resected. A 57-year old male with ataxia and mild hypogeusia was admitted to our hospital. MRI demonstrated a well-circumscribed large posterior fossa mass with extracranial extension through the internal jugular vein. Two-staged surgical treatment was then performed. The mass in the posterior fossa was removed at the first operation. The tumor was invading into the sigmoid sinus which was filled with tumor. The second operation for extracranial mass was performed 1 month later. Transcervically, the internal jugular vein obstructed by tumor was successfully removed. The post-operative course was uneventful and histopathological examination revealed the fibrous meningioma in the posterior fossa, but the intravenous portion of the tumor showed more atypical findings. Such a case is quite uncommon and the mechanism of tumor extension with different histological features is discussed.