Fatal convexity and interhemispheric acute subdural hematoma from a falx meningioma: A case report

Background: Hemorrhagic meningiomas are rare. We report a rare case of nontraumatic convexity and interhemispheric acute subdural hematoma (ASDH) caused by a falx meningioma. Case Description: An 84-year-old woman with a history of atrial fibrillation and hypertension who was taking warfarin presented to our emergency department with a sudden disorder of consciousness. The patient had no traumatic events associated with her symptoms. Computed tomography (CT) revealed right convexity and interhemispheric ASDH, mass lesions in the left frontal lobes, and brain herniation. Contrast-enhanced CT revealed vascular structures within the mass lesion. CT angiography (CTA) revealed no aneurysm or arteriovenous malformation, and the venous phase revealed occlusion in the anterior portion of the superior sagittal sinus. The patient had her right convexity and interhemispheric ASDH removed endoscopically. A mass lesion located on the falx, which was easily bleeding, soft, and suctionable, was immediately detected. Histopathological examination revealed fibrous meningioma, a benign meningioma of the World Health Organization grade 1. Despite undergoing aggressive treatment, the patient’s general condition deteriorated. Conclusion: Hemorrhagic meningiomas can easily be missed with plain CT, and the enhancement effect of CTA and tumor shadow on digital subtraction angiography may not be observed during the acute phase. Surgery for nontraumatic ASDH should be performed considering the possibility that a meningioma causes it.