Dural cavernous angioma causing acute subdural hemorrhage--case report.

A 78-year-old female presented with a nontraumatic acute subdural hematoma (ASDH) caused by hemorrhage from a cavernous angioma located on the convexity dura mater. The hematoma and angioma were removed successfully. Neuroimaging performed 2 years previously had not revealed cavernous angioma. The angioma most likely grew rapidly over the 2 year period, during which she had received oral antiplatelet medication. Nontraumatic ASDH may originate from a cavernous angioma which grows rapidly.