Posterior perspective of sphenoid bone. The sphenoid bone (dorsal view) forms the axis of the skull base. It has a greater and a lesser wing, with the superior orbital fissure (SOF) in between them. The maxillary strut separates the SOF from the foramen rotundum. The pituitary gland sits on the sella which is limited anteriorly by the tuberculum sellae. The prechiasmatic sulcus extends in between the optic canals, and the limbus of the sphenoid separates planum sphenoidale from prechiasmatic sulcus. The lesser wing continues medially with the anterior clinoid process. The posterior wall of the sella is formed by the dorsum sella, which continues supero-laterally with the posterior clinoids. Lateral to the body of the sphenoid and sella we identify the carotid sulcus in the parasellar space. (Image courtesy of JC Fernandez-Miranda)