A Case of Subarachnoid Hemorrhage Treated with Unilateral-Bypass-assisted Surgery for Multiple Aneurysms Involving the Bilateral Posterior Inferior Cerebellar Arteries

Abstract

A woman in her 50s presented with a subarachnoid hemorrhage and three bilateral aneurysms involving the posterior inferior cerebellar arteries (PICAs): one on the left side and two on the right side. The aneurysm of the left PICA was diagnosed as the rupture site, as vessel wall enhancement was observed on magnetic resonance imaging, suggesting a dissecting aneurysm. Bilateral occipital artery-PICA bypass was planned, but only a unilateral bypass was performed to treat a distal aneurysm of the right PICA. The remaining two aneurysms were successfully clipped. Postoperatively, the patient developed ischemic complications at the skin flap, necessitating additional skin transplantation. Identifying the rupture site in cases of multiple aneurysms can be challenging to diagnose. In such situations, vessel wall enhancement on magnetic resonance imaging may aid in diagnosis. Multiple aneurysms affecting bilateral PICAs presenting with subarachnoid hemorrhage can be surgically managed through a combination of bypass surgery and aneurysm clipping, with careful preoperative planning and consideration of ischemic risks at the skin flap.