Superior view of sphenoid bone. This view presents the midline body and paired greater and lesser wings of the sphenoid. The body and lesser wings form the anterior boundary of the middle cranial fossa, while the greater wings and squamous portions of the temporal bones form the lateral margins. The middle fossa is bounded posteriorly by the petrous portions of the temporal bones. The body consists anteriorly of the smooth surfaced planum sphenoidale that connects the right and left lesser wings (and roofs the anterior most part of the sphenoid sinus), the chiasmatic sulcus, the tuberculum sellae, sella turcica, and dorsum sellae. The optic nerves exit the orbit through the optic canals within the lesser wings and the anterior portion of the optic chiasm lies within the prechiasmatic sulcus. The central depression within the sella turcica is the hypophyseal fossa which is occupied by the hypophysis (pituitary gland). Pairs of clinioid processes project from the lesser wings (anterior), lateral edges of the tuberculum sellae (middle), and from lateral margins of the dorsum sellae (posterior). The greater wings contain a "crescent" of foramina beginning anteriorly as the superior orbital fissure between the lesser and greater wings (not labeled here), the foramen rotundum for the maxillary nerve,  the foramen ovale for the mandibular and lesser petrosal nerves, and the foramen spinosum for the middle meningeal artery. Medial to the foramen ovale in this specimen are inconstant bilateral sphenoidal emissary foramina (foramen of Vesalii) for passage of a vein from the pterygoid venous plexus to the cavernous sinus.  (Image courtesy of AL Rhoton, Jr.)