Ruptured Distal Accessory Anterior Cerebral Artery Aneurysm: A case report and literature review.

Aneurysms of the distal anterior cerebral artery (dACA) are rare, consisting only 2-6% of all intracranial aneurysms. dACA aneurysms are often associated with anomalies such as azygous, bihemispheric and triplication of ACA. Among these anomalies accessory anterior cerebral artery (accACA) is an anatomical variant found in 3.3% to 15% of the population. Here we report a case of a 60-year-old female who presented with a Hunt and Hess grade II, Fisher grade III subarachnoid hemorrhage secondary to a ruptured saccular aneurysm originating from the pericallosal-callosomarginal artery bifurcation at the A3 segment of the accessory ACA and underwent an uncomplicated microsurgical clipping.