Posterior Cerebral Artery in the Skull, Superior View

Description

Seen from a superior calvarial opening, the posterior cerebral artery (PCA) courses posterolaterally from the basilar bifurcation at the level of the interpeduncular cistern, wrapping around the midbrain toward the medial temporal lobe and occipital lobe. Proximally, the P1 segment sits medial to the oculomotor nerve (CN III) and connects anteromedially to the internal carotid circulation via the posterior communicating artery within the circle of Willis. Distally, the P2 segment tracks along the ambient cistern, giving rise to cortical branches that fan over the inferomedial temporal surface and the calcarine region. Bony context from the cranial base and foramina remains visible inferiorly, anchoring the arterial course to the clivus and petrous temporal margins. A superior intracranial view helps you teach and plan around PCA territory ischemia, where occlusion classically produces contralateral homonymous hemianopia from infarction of the calcarine cortex, sometimes with macular sparing when collateral flow persists. The P1 segment is also the key anatomical substrate for posterior circulation aneurysms near the basilar tip, and its relationship to the posterior communicating artery explains fetal-type PCA variants that shift occipital perfusion to the internal carotid system. Small perforators from P1 and P2 to the thalamus and midbrain are easy to underestimate. They matter. Use this artwork for neuroanatomy and neurovascular modules, stroke education materials that distinguish posterior from anterior circulation syndromes, and operative or endovascular planning figures discussing basilar tip and PCA aneurysm corridors relative to the midbrain and cranial nerves. Anatomical accuracy verified by SciePro's Medical Advisory Board.