Origin of the Posterior Inferior Cerebellar Artery over the C1 Posterior Arch

Abstract

Resumo The posterior inferior cerebellar artery usually arises from the intracranial segment (V4) of the vertebral artery. Despite its mean diameter of 2 mm, it usually irrigates important areas of the brain. When occluded, whether due to trauma or surgery, it may cause infarction in the brain stem and cerebellum. The present report describes a case of incidental finding of a posterior inferior cerebellar artery arising from the cervical segment (V3) of the vertebral artery, demonstrated by angiography. The findings were recorded and compared to those of earlier publications. Brief explanations regarding anatomy, vascular anomalies and embryology were provided. A literature review showed that anomalous branches of the cervical segment of the vertebral artery are infrequent andmust be known. A better understanding of anatomy and its variations enables an accurate topographic diagnosis, as well as the planning of the optimal surgical approach and therapy. Knowledge of this anatomical variation is essential because, if it is mistaken for a muscle branch and coagulated, this can cause ischemia and disabling sequelae.

Keywords

• vertebral artery
• cerebral angiography
• anatomic variation
• lateral medullary syndrome
• intraoperative complications