Unusual Intracranial Parasagittal Meningioma Extending into the Internal Jugular Vein through the Sinuses.

Meningiomas frequently invade cerebral venus sinuses, especially parasagittal meningioma to superior sagittal sinus. However, most invasions do not reach internal jugular vein. We present a case of parasagittal meningioma extending into the internal jugular vein through the sinuses. Radiological investigation revealed that the tumor was invading the sagittal, transverse, sigmoid sinus and junction of the internal jugular vein to subclavian vein, which was filled with tumor. The histopathological examinations revealed that both the cerebral tumor and mass in the internal jugular vein contributed to the transitional meningioma. This is a rare case of a meningioma extending into the internal jugular vein through the sinuses. According to this case, the frontal parasagittal meningioma could invade directly the internal jugular vein. The significance of this association to cerebral venus sinuses and internal jugular vein are discussed.