Meningioma of the fourth ventricle presenting with intermittent behaviour disorders: a case report and review of the literature.

Intraventricular meningiomas are rare, representing 0.5-5% of all intracranial meningiomas. They arise mostly within the lateral ventricles and more rarely in the third ventricle. Meningiomas of the fourth ventricle are exceptional. They are clearly defined as meningiomas arising from the choroid plexus and lying strictly within the fourth ventricle. We report a 76 year old male patient presenting with a 2-week history of headache and cognitive disorders with agitation and restlessness particularly exacerbated at night or when lying down. CT scan and MR imaging showed a contrast-enhancing lesion located purely within the whole fourth ventricle, with slight ventricular enlargement. At surgery, we totally removed a well-vascularised, greyish encapsulated mass attached to the choroid plexus. Pathological examination revealed a WHO grade I fibroblastic meningioma. We reviewed the literature concerning this unusual meningioma location.