Abstract
We experienced a case with a ruptured anterior cerebral artery aneurysm encased in the tuberculum sellae meningioma, which we treated successfully. Although several cases of coexistent of cerebral aneurysms and a meningiomas have been reported, encasement of an aneurysm in a meningioma is extremely rare. There has been only one report so far. The patho mechanism of the coexistent of these two lesions is still an unsolved problem. Several ideas have been proffered to explain the mechanism. In our case, the meningioma may highly contribute to cause aneurysmal development. Usually, a ruptured aneurysm case is diagnosed with CT and angiography preoperatively. In this situation, the anatomical relation of tumor and aneurysm may not be demonstrated in detail. Therefore, careful microsurgical resection is be required.
