Inferior Perspective of the Posterior Cerebral Artery

Description

Oriented from an inferior (basal) perspective, the posterior cerebral artery (PCA) is visualized as the terminal branch of the basilar artery at the pontomesencephalic junction, coursing posteriorly around the cerebral peduncle within the ambient cistern. Proximally, the P1 segment runs medial to the oculomotor nerve (CN III) and connects via the posterior communicating artery to the internal carotid system as part of the cerebral arterial ring (circle of Willis). Distally, the PCA sweeps laterally and posteriorly toward the medial temporal and occipital lobes, giving off perforators to the thalamus and midbrain and cortical branches that track along the inferior surface of the hemisphere. Color coding separates arteries from accompanying veins and cranial nerves. Clear and legible. This basal view matters because it lays out the PCA’s relationship to the cerebral peduncle and CN III, an anatomic pairing that frames both aneurysm evaluation at the P1–posterior communicating junction and surgical corridors to the interpeduncular and ambient cisterns. PCA territory infarction classically produces contralateral homonymous hemianopia from occipital cortex ischemia, and thalamic or midbrain involvement from perforator compromise can add hemisensory loss or vertical gaze deficits. The illustration also supports teaching the circle of Willis as a functional anastomosis, including where collateral flow may or may not compensate during carotid or basilar stenosis. Use this artwork in neuroanatomy and neurovascular modules to teach PCA segments (P1–P4), perforator patterns, and the basal emergence of cranial nerves, or in neurology and neurosurgery texts discussing posterior circulation stroke syndromes and aneurysm localization. It also fits radiology teaching files as a companion schematic for CTA/MRA correlation of the circle of Willis from the skull base. Anatomical accuracy verified by SciePro's Medical Advisory Board.