[CT Manifestation of Pterygopalatine Fossa in Adult Skull]

Objective: The aim of this study was to measure certain diameters of the pterygopalatine fossa (PPF) and to discuss the anatomic appearance of PPF on CT images.

Methods: 20 dry skulls were scanned by CT on axial and coronal plane with 2 mm slice thickness.

Results: On CT imaging, the shape of superior 1/4 part of PPF is mainly shown as biconcavity. The maximal posteroanterial (PA)diameter was (6.6+/-2.2)mm. The maximal medialateral diameter (ML)was (13.7+/-3.7)mm. The shape of the middle 1/4 part of PPF was biconvexity with the PA and ML of (6.6+/-2.1)mm and (12.1+/-2.7)mm. The shape of the inferior 1/2 part of PPF just liked a tube with the diameter of (3.8+/-1.7)mm. The foramen rotudum lied (5.2+/-2.3)mm under the inferior orbital fissure. The pterygoid canal lied (7.4+/-2.5)mm medial and (6.2.+/-4.2)mm inferior to the foramen rotudum.

Conclusion: PPF has various shapes on axial and coronal CT images. Based on the distances and the relationship between the foramen and fissures, the normal and abnormal status of PPF can be evaluated.