Résumé
BACKGROUND AND OBJECTIVES: Sphenoid sinus is surrounded by several important structures and this can make sphenoid sinus surgeries difficult. The aim of this study was to clarify the anatomical features of the sphenoid sinus with its surrounding structures based on 3-dimensional multidetector computed tomography. SUBJECTS AND METHOD: We obtained the sagittal reconstruction images of the sphenoid sinus from of 110 participants and measured various distances in the sphenoid sinus. In addition, we analyzed the impact of anatomical variation on the results of measured distances, such as presence of Onodi cell (Onodi type vs. non-Onodi type) and the location of sphenoid ostium corresponding to the level of sella floor (superior type vs. inferior type). RESULTS: In the Onodi type, the mean distance from the sphenoid ostium to the roof of sphenoid sinus (5.81+/-1.12 mm vs. 10.31+/-2.90 mm, p=0.001) and the mean length of sphenoid sinus roof (4.52+/-1.00 mm vs. 9.89+/-4.17 mm, p=0.001) were significantly shorter than those in the non-Onodi type. In superior type, the mean distance from the sphenoid ostium to the floor of sphenoid sinus (12.44+/-2.63 mm vs. 9.90+/-2.31 mm, p<0.001) and that from sphenoid ostium to the posterior wall of sphenoid sinus (13.44+/-3.27 mm vs. 20.38+/-7.63 mm, p<0.001) were significantly longer compared with those in the inferior type. However, the mean distance from the sphenoid ostium to the roof of sphenoid sinus was shorter (7.49+/-1.86 mm vs. 10.51+/-3.03 mm, p<0.001). CONCLUSION: The present study provides anatomical information about sphenoid sinus with important surgical distance measured between the sphenoid ostium and the surrounding structures, which is essential to avoid the complications during sphenoid surgery.