Morphological study of the pterygoid canal with high-resolution CT

The purpose of our study was to accurately visualize and measure the normal anatomy and size of the pterygoid canal with thin-section (0.5 mm), high-resolution computed tomography (HRCT) as well as multiplanar reconstruction (MPR) and curved planar reconstruction (CPR) technologies to obtain credible and comprehensive information for clinical management. Both axial HRCT and MPR images of the pterygopalatine fossa were obtained in 167 normal adult subjects, who exhibited variable positions of pterygoid canal relative to the sphenoid sinus floor and cavity. The morphology and size of the pterygoid canal was observed and measured, respectively. All pterygoid canals (100%, 334/334) were well delineated on HRCT images. Statistical analyses showed no significant difference between the mean length of the left (12.6 ± 2.3 mm) and right pterygoid canals (12.5 ± 2.9 mm) (P = 0.405). The mean diameter of anterior, median and posterior opening of the left and right pterygoid canals exhibited no significant differences (all P > 0.05); the bilateral median opening possessed the smallest diameter (P < 0.001). Submillimeter, thin-section HRCT scan and appropriate postprocessing reconstruction technologies could clearly visualize the morphologic features of the pterygoid canal and adjacent structures, which may be helpful for making diagnostic and therapeutic decisions.