Posterior inferior cerebellar artery

Artery: Posterior inferior cerebellar artery
The three major arteries of the cerebellum: the SCA, AICA, and PICA. (Posterior inferior cerebellar artery is PICA.)
Diagram of the arterial circulation at the base of the brain. (PICA is labeled at bottom right.)
Latin arteria cerebelli inferior posterior
Gray's subject #148 580
Supplies cerebellum, choroid plexus of the fourth ventricle
Source vertebral artery   
Branches medial branch
lateral
Vein inferior cerebellar veins

The posterior inferior cerebellar artery (PICA), the largest branch of the vertebral artery, is one of the three main arterial blood supplies for the cerebellum, part of the brain. Occlusion of the posterior inferior cerebellar artery or one of its branches, or of the vertebral artery leads to Wallenberg syndrome, also called lateral medullary syndrome.

Course

It winds backward around the upper part of the medulla oblongata, passing between the origins of the vagus and accessory nerves, over the inferior cerebellar peduncle to the undersurface of the cerebellum, where it divides into two branches.

The medial branch continues backward to the notch between the two hemispheres of the cerebellum; while the lateral supplies the under surface of the cerebellum, as far as its lateral border, where it anastomoses with the anterior inferior cerebellar and the superior cerebellar branches of the basilar artery.

Branches from this artery supply the choroid plexus of the fourth ventricle.

Diseases

Infarction of this artery due to thrombosis or a stroke leads to lateral medullary syndrome, also known as PICA syndrome or Wallenberg syndrome. Severe occlusion of this or vertebral arteries could lead to Horner's Syndrome as well.

External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.