Primitive hypoglossal artery associated with basilar artery aneurysm.

A case of persistent primitive hypoglossal artery, accompanied by a basilar bifurcation aneurysm, is reported. The persistent primitive hypoglossal artery was seen on the right side and the left vertebral artery was hypoplastic. The right vertebral artery was absent, while a normal sized posterior communicating artery was seen on the right side at the operation on the aneurysm. The combination of a basilar bifurcation aneurysm and a persistent primitive hypoglossal artery is rare. A review of related reports has been made.