Clipping of Ruptured Aneurysm of Lateral Spinal Artery Associated with Anastomosis to Distal Posterior Inferior Cerebellar Artery: A Case Report

Background Arteries that anastomose with the posterior inferior cerebellar artery (PICA) can harbor aneurysms. Case Description We present a case of a patient who suffered a subarachnoid hemorrhage as a result from an aneurysm on the left lateral spinal artery (LSA) that anastomosed to the PICA. The aneurysm was treated surgically, and the flow between the LSA and PICA was disrupted. The activated anastomotic network created a new anastomosis between the LSA and PICA, which was seen at 6 months' follow-up. Conclusions Careful follow-up is warranted in patients who have an activated anastomotic network because they can potentially develop aneurysms on newly created anastomoses.