Imaging description

Literally meaning a slope, the clivus is the part of the central skull base sloping upward from the foramen magnum to the dorsum sellae. It is composed of basisphenoid and basiocciput and thus forms an important boundary of the posterior skull base, but is easily accessible from the middle skull base.

Lesions of the clivus are predominantly osseous and mainly neoplastic [1]. It may be a primary mass arising from clivus such as chordoma [2]; secondary involvement from an adjacent primary such as invasive pituitary macroadenoma, chondrosarcoma, or nasopharyngeal carcinoma; part of a multicentric systemic process such as multiple myeloma and plasmacytoma; metastatic secondary deposits from a primary elsewhere in the body; or a metabolic bone process such as fibrous dysplasia or Paget’s disease. Imaging with MRI and CT can help to differentiate amongst these conditions and arrive at a narrow and focused diagnostic possibility.