Giant serpentine aneurysms

Segal and McLaurin first described giant serpentine aneurysms, based on their distinct angiographic features, in 1977. These lesions are >= 25 mm, partially thrombosed aneurysms with a patent, serpiginous vascular channel that courses through the aneurysm. There is a separate inflow and outflow of the aneurysm, of which the outflow channel supplies brain parenchyma in the territory of the parent vessel. Given the large size, unique neck, and dependent distal vessels, these aneurysms pose a technical challenge in treatment. Initial management has included surgical obliteration, but as endovascular techniques have evolved, treatment options too have expanded. In this review the authors attempt to summarize the existing body of literature on this rare entity and describe some of their institutional management strategies. (DOI: 10.3171/2009.2.FOCUS0918)