Anterior transphenoidal section that reveals several anatomic spaces and structures. In the midline is the sphenoid sinus within the body of the sphenoid. Inferior to this is the junctional area between the nasal cavity and nasopharynx. On either side of the nasal septum the Eustachian tubes can be seen through the choane projecting into the lateral wall of the nasopharynx. The temporal lobes rest on the greater wings of the sphenoid bone and the superior orbital fissure, the space between the lesser and greater wings, contain nerves entering the orbit. The pterygoid processes divide inferiorly into medial and lateral pterygoid plates. The latter are related to the infratemporal fossa. This fossa contains the mandibular nerve and major portion of the maxillary artery (as well as the pterygoid venous plexus). The lateral pterygoid muscle consists of two heads. The superior head attaches to the undersurface of the greater wing of sphenoid, while the inferior head attaches to the lateral surface of the lateral pterygoid plate. The medial pterygoid muscle attaches to the medial surface of this bony plate. The pterygopalatine fossa is bounded posteriorly by the upper aspect of the pterygoid process and receives the maxillary and Vidian nerve. This fossa communicates laterally with the infratemporal fossa via the pterygomaxillary fissure and receives the terminal portion of the maxillary artery. (Image courtesy of AL Rhoton, Jr.)