Anterior Cerebral Artery within the Skull

Description

Within the male cranial cavity, the anterior cerebral artery (ACA) courses anteromedially from the internal carotid artery and curves superiorly to run along the medial surface of the cerebral hemisphere as the pericallosal artery, accompanied by the callosomarginal branch in typical patterns. Proximally, the right and left A1 segments converge toward the midline and are joined by the anterior communicating artery, completing the anterior portion of the Circle of Willis at the level of the optic chiasm and lamina terminalis. Distally, the A2 and more distal segments track superior to the corpus callosum, sending cortical branches toward the medial frontal and parietal lobes. Small penetrating arterioles arise near the anterior communicating complex to supply deep structures. That anterior communicating region matters clinically because it is the most common site for intracranial saccular aneurysms, and rupture often presents with subarachnoid hemorrhage and early frontal lobe signs such as abulia or impaired executive function. Surgeons and interventionalists also use the A1 caliber and dominance to plan clipping or endovascular coiling, since hypoplastic A1 segments shift flow demand across the anterior communicating artery and alter collateral routes during proximal occlusion or vasospasm. Landmark anatomy. It guides orientation at the skull base. Use this illustration for teaching cerebral arterial supply in neuroanatomy, head and neck anatomy, and neurosurgical approaches to the anterior cranial fossa, and for pairing with angiography figures in stroke, aneurysm, and subarachnoid hemorrhage publications where ACA segment terminology (A1 to A3) must be unambiguous. Anatomical accuracy verified by SciePro's Medical Advisory Board.