Multiple peripheral aneurysms of the posterior inferior cerebellar artery

Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare. The authors describe a case in which five distinct peripheral aneurysms of the PICA were diagnosed and microsurgically clipped while preserving the parent vessel. One of the aneurysmal sacs was excised and examined pathologically, and no evidence of an infectious etiology was found. The surgical approach to peripheral PICA aneurysms is discussed and the literature concerning these unusual aneurysms is reviewed.