Intracerebral hematoma simulating a new growth.

Three cases of organized intracerebral hematomas presented slowly progressive neurological deficits and hence mimicked brain tumors. Computed tomography scanning revealed ring enhancement of intracerebral mass lesions with midline shift. Angiographic studies showed avascular mass lesions. Soft, well-encapsulated, organized, large intracerebral hematomas with feeding arteries on their capsules were removed surgically. The lesions contained fresh and old hemorrhages. It is presumed that the feeding artery caused slowly continuous bleeding, thus causing these intracerebral hematomas to grow in a manner that made their clinical picture simulate that of intracerebral neoplasms. Their pathogenesis is discussed.