Clivus

The clivus, which means “slope”, is a gentle bony surface in the midline region of the posterior cranial fossa. It begins behind the dorsum sellae of the sphenoid bone and extends to the front edge of the large opening at the base of the skull called the foramen magnum. The clivus is formed by the fusion of two bones: the basisphenoid (part of the sphenoid bone) and the basiocciput (part of the occipital bone).

On the clivus, the brainstem, particularly the pons and medulla oblongata, rest. The basilar artery, which runs along the ventral surface of the pons, forms the immediate posterior relation of the clivus.