The clivus: anatomy, normal variants and imaging pathology.

The clivus is one of the most central parts of the skull base. As diseases of the clivus evade clinical evaluation imaging plays a pivotal role in establishing a diagnosis. This article combines the description of anatomy and pathology with an extensive pictorial essay. Starting with the development and normal macroscopic anatomy of the clivus the reader is then introduced to a large variety of normal variations and developmental disorders some of them with clinical significance. Typical examples of non-neoplastic and neoplastic masses of the clivus and their differential diagnoses are provided. The article concludes with a review of inflammatory disease and trauma.