Association of arteriovenous malformation and intracranial aneurysm in the posterior fossa.

Two cases of a saccular aneurysm of the posterior inferior cerebellar artery associated with an anatomically related arteriovenous malformation are presented. The aneurysms were clipped and the arteriovenous malformations were totally extirpated in one-stage operations in both cases. The association of arteriovenous malformation and arterial aneurysm in the posterior fossa was reviewed in the literature.