Pterygopalatine fossa

The pterygopalatine fossa is a small, triangular space at the angle of junction of the inferior orbital and pterygomaxillary fissures, and placed beneath the apex of the orbit.

It is bounded:

• above by the under surface of the body of the sphenoid and by the orbital process of the palatine bone
• in front, by the infratemporal surface of the maxilla;
• behind, by the base of the pterygoid process and lower part of the anterior surface of the great wing of the sphenoid;
• medially, by the vertical part of the palatine bone with its orbital and sphenoidal processes.

This fossa communicates with the orbit by the inferior orbital fissure, with the nasal cavity by the sphenopalatine foramen, and with the infratemporal fossa by the pterygomaxillary fissure. Five foramina open into it. Of these, three are on the posterior wall, viz., the foramen rotundum, the pterygoid canal, and the pharyngeal canal, in this order downward and medialward. On the medial wall is the sphenopalatine foramen, and below is the superior orifice of the pterygopalatine canal.

The fossa contains the maxillary nerve, the sphenopalatine ganglion, and the terminal part of the internal maxillary artery.