Cranial Fossa, Posterior

**Definition:** The infratentorial compartment that contains the CEREBELLUM and BRAIN STEM. It is formed by the posterior third of the superior surface of the body of the sphenoid (SPHENOID BONE), by the occipital, the petrous, and mastoid portions of the TEMPORAL BONE, and the posterior inferior angle of the PARIETAL BONE.

**Tree numbers:** - A01.456.830.200 - A02.835.232.781.750.400