The neglected anatomical and clinical aspects of pterygoid canal: CT scan study

To present the variable positions of pterygoid canal (PC) relative to sphenoid sinus floor and cavity, which may be helpful for understanding pathologic and surgical conditions related to sphenoid sinus region.

Coronal sinonasal CT images of 300 adult patients, in the Department of Radiology at Al-Jala Traumatology Hospital, Benghazi, Libya, were investigated for the positional variation and dehiscence of PC. Of the patients, there was equal gender distribution, ages ranged between 16 and 82 years (mean age 34.6 years). The position of PC was categorized as below the sinus floor, within the floor, and within the sinus cavity (protrusion).

Canals located under the floor were identified in 38.3% (230/600), within-the-floor canals were encountered in 39.6% (238/600); and canals protruding into the sinus cavity (i.e., within sinus cavity) were observed in 22% (132/600). Dehiscence of the bony wall of PC was recognized in 26% (157/600). Coexistence of PR and protruding PC was found in 16.5% (99/600), 7.3% (44/600) on the right side and 9.2% (55) on the left side. Statistically, there was significant association between PR and PC protrusion (p = 0.000).

The anatomical and positional variations of PC are highly encountered. Surgeons addressing vidian neurectomy must be familiar with the positional variations of PC in the preoperative CT images for easier and safer nerve identification and transection.