Middle Cerebral Artery Aneurysm and Distal Anterior Cerebral Artery (DACA) Aneurysms Related to Azygos and an Unusual Single Pericallosal Artery Variant: A Case Report

The authors describe the case of multiple rare distal anterior cerebral artery (DACA) aneurysms related to a middle cerebral artery (MCA) aneurysm, an azygos, and an undescribed anterior cerebral artery (ACA) anatomical variation. A 61-year-old woman in a severe clinical state was diagnosed with subarachnoid hemorrhage (SAH) secondary to a ruptured anterior A3 DACA aneurysm. The patient also had unruptured kissing superior A3 DACA aneurysms, an atherosclerotic DACA aneurysm between the anterior and superior DACA aneurysms, and an unruptured MCA left aneurysm. Two pericallosal anatomical variations were seen: an A2 azygos and a rare single post-bifurcation (callosomarginal artery) pericallosal artery. All aneurysms were clipped using a single-staged left craniotomy with interhemispheric, subfrontal, and transsylvian access. This study demonstrates a patient with rare anatomical ACA variants and multiple complex aneurysms treated in a single-stage craniotomy.