High-resolution CT of the pterygopalatine fossa and its communications

Abstract

The pterygopalatine fossa is an important space because it communicates with the middle cranial fossa, orbit, nasal cavity, oral cavity, pharynx, foramen lacerum, and the infratemporal fossa via eight foramina and canals. We studied the pterygopalatine fossa, foramen rotundum, inferior orbital fissure, sphenopalatine foramen, pterygoid canal, greater and lesser palatine foramen, palatinovaginal canal, and the pterygomaxillary fissure with high-resolution CT to characterise the anatomy and variants of these structures. These structures were evaluated using axial and coronal planes. In the morphometric study, the distance between the foramina rotunda did not show statistically significant differences between the anterior and posterior segments. The pterygoid canal was slightly narrower in the anterior segment (23.9 mm) than in the posterior segment (25.2 mm). The pterygoid canal narrowed in the anterior (1.8 mm) to posterior (1.2 mm) direction (P < 0.01). The distance between the pterygoid canal and the lower wall of the sphenoid sinus was 2.2 mm anteriorly and 2.8 mm posteriorly (P < 0.01). The pterygoid canal showed various relationships with the sphenoid and ethmoid sinuses. In addition, a previously unreported situation, where the foramen rotundum was surrounded by the spheroid sinus, was observed.