Posterior Inferior Cerebellar Artery Viewed from Below

Description

Arising from the intracranial segment of the vertebral artery, the posterior inferior cerebellar artery (PICA) is traced in an inferior (basal) view as it winds posteriorly around the lateral medulla before turning onto the undersurface of the cerebellar hemisphere. The paired vertebral arteries and proximal basilar artery lie in the midline plane, with PICA coursing posterolaterally toward the cerebellar tonsil and inferior vermis, while the medulla oblongata and cervicomedullary junction sit centrally and inferiorly. Cranial nerves at the pontomedullary and medullary levels emerge as yellow bundles, framing the cerebellomedullary cistern where PICA typically makes its most characteristic loops. Gyri and sulci on the inferior cerebral surface provide orientation superior to the brainstem. This perspective matters because PICA is the dominant arterial supply to the dorsolateral medulla and inferior cerebellum, the vascular territory involved in lateral medullary (Wallenberg) syndrome and a common source of posterior circulation stroke symptoms. Its sinuous course around the medulla also explains why PICA aneurysms and dissections can present with lower cranial nerve findings, and why surgeons and interventionalists treat the vertebral artery, PICA origin, and tonsillomedullary segment as high-stakes landmarks. Small perforators from PICA to the medulla are unforgiving. You want to see the loops. Use this basal 3D rendering in neuroanatomy and neuroradiology teaching to correlate vertebrobasilar circulation with cranial nerve root exit zones, and in stroke education to map clinical deficits to PICA territory. It also suits atlases and operative planning references for far-lateral and retrosigmoid approaches, where the vertebral artery, PICA, and cerebellomedullary cistern are encountered early. Anatomical accuracy verified by SciePro's Medical Advisory Board.