Giant serpentine intracranial aneurysm.

Giant serpentine aneurysms are considered a distinct subgroup of giant aneurysms because of their characteristic angiographic appearance and clinical behavior. A case of this unusual vascular abnormality showing progressive enlargement documented by computed tomography and cerebral angiography is presented, along with a review of the literature. Etiology, pertinent radiological findings, and a probable mechanism of serpentine channel formation are discussed.