Persistent trigeminal artery feeding a hemispheric branch of the posterior inferior cerebellar artery: A rare anatomic variant

SummaryPersistent trigeminal artery is a rare persistent carotid-basilar anastomosis that usually connect the infracavernous segment of the ICA with the basilar artery. Rarely, PTA may feed cerebellar artery. We describe an exceptional case of PTA terminating in postero-inferior cerebellar artery (PICA) hemispheric branch. Angiographic and CTA features are presented and hypotheses regarding developmental origin of this variation are discussed.