Basal perforating artery aneurysm within the cavum septi pellucidi. Case report.

The authors describe the case of a 16-year-old boy presenting with clinical onset of subarachnoid hemorrhage. The patient was found to have a small aneurysm arising from the distal portion of a basal perforating branch of the anterior cerebral artery (ACA), lying within a cavum septi pellucidi. Neuroimaging demonstrated a hematoma within the cavum septi pellucidi and the aneurysm was resected via a transcallosal approach guided by an intraoperative portable digital subtraction angiography (DSA) system. The origin of the aneurysm was presumed to be idiopathic. This report is the first to describe an aneurysm of a basal perforating artery arising from the ACA that resulted in an intracaval hematoma. When approaching small vascular lesions during surgery, intraoperative DSA is the method of choice to identify the precise trajectory and distance to the lesions.