Posteromedial Central Arteries within the Skull, Superior View

Description

Viewed from superior after a calvarial cross section, the arterial tree is centered on the Circle of Willis, where the internal carotid arteries give rise to the anterior cerebral arteries joined by the anterior communicating artery, while the posterior communicating arteries link forward to the posterior cerebral arteries fed by the basilar apex. From the proximal anterior and middle cerebral trunks, the posteromedial central arteries (perforating arteries) dive inferiorly and posteriorly through the anterior perforated substance toward the deep gray nuclei. Small-caliber arterioles track close to the midline around the optic chiasm and hypothalamic region, with bilateral symmetry framed by the cut margins of the cranial vault. Perforators in this territory matter because they behave like end arteries once they enter the brain substance, and their occlusion produces classic lacunar infarcts of the thalamus, internal capsule, and basal ganglia. A small hemorrhage here can be devastating. This superior perspective also clarifies why aneurysms at the anterior communicating artery, posterior communicating artery, and basilar tip sit immediately adjacent to perforating branches that surgeons try to preserve during clipping or endovascular coiling. Use this artwork for neuroanatomy and neuroradiology teaching when correlating the Circle of Willis with deep stroke syndromes, or for neurosurgical and neurology texts discussing perforator infarction, aneurysm anatomy, and subarachnoid hemorrhage patterns within the cranial cavity. Anatomical accuracy verified by SciePro's Medical Advisory Board.