Growth of multiple peripheral high flow aneurysms of the posterior inferior cerebellar artery associated with a cerebellar arteriovenous malformation.

A case of three high flow peripheral aneurysms of the posterior inferior cerebellar artery (PICA) associated with a left cerebellar arteriovenous malformation is presented. This rare association is of further interest because the patient had been diagnosed as harboring an arteriovenous malformation 3 years before her most recent subarachnoid hemorrhage. Repeat angiography revealed enlargement of the malformation with new growth of three peripheral PICA aneurysms at the telovelotonsillar segment. Successful excision of the malformation and obliteration of all three aneurysms were accomplished. The causal mechanism of increased cerebral blood flow in the generation of the peripheral cerebral aneurysms is demonstrated.