What Is a Cerebellar Artery?

The cerebellar artery is an artery that delivers blood to the cerebellum. Named for the Latin term for “little brain,” the cerebellum is the smaller part of the brain’s lower region responsible for the human body’s motor control, which is essential for movement. The cerebellum also contributes to cognitive functions such as communication and attention. Thus, the cerebellar artery is instrumental in ensuring that the cerebellum functions properly. It also goes by the term arteria cerebelli.

There are three major cerebellar arteries, or blood vessels that function as the cerebellum’s primary source of blood. They are the anterior inferior cerebellar artery, the posterior interior cerebellar artery and the superior cerebellar artery. The anterior and posterior arteries and the superior artery are classified as “inferior” and “superior,” respectively, because the latter is placed above the former. These adjectives also correspond to the area of the cerebellum that each cerebellar artery is responsible for supplying.

The posterior inferior cerebellar artery (PICA) is the bottommost of the cerebellar arteries. It is the largest branch of the vertebral arteries, which functions as the neck’s major arteries. The posterior artery traverses past the lower part of the brain stem called the medulla oblongata and some cranial nerves. At the cerebellum it splits into two branches. The lateral one supplies blood to the little brain’s under surface, while the medial branch continues its journey backward to an area lodged between the cerebellum’s two hemispheres.

Located above the PICA is the anterior inferior cerebellar artery (AICA). It originates from the basilar artery, which joins with the vertebral arteries to form the vertebrobasilar system that supplies oxygenated blood to the brain. Like the posterior artery, the AICA passes through the brain stem. The specific area of the cerebellum it supplies is the front section of its under surface, right before and above the area that is supplied by the PICA.

The superior cerebellar artery (SCA) comes from the area of the basilar artery’s termination. It is responsible for supplying the cerebellum’s top half. The SCA also supplies parts of the midbrain, which is situated above the cerebellum.

In pathology, which is the study of diseases, the PICA is implicated in neurological disorders such as lateral medullary syndrome, or PICA syndrome, and Horner's syndrome due to tissue death or blockage. Obstruction of the AICA can lead to lateral pontine syndrome, or AICA syndrome. The condition trigeminal neuralgia is caused by the SCA compressing the trigeminal nerve.