Three-dimensional bone CT reconstruction anatomy of the vidian canal

Objectives: To examine the anatomical features of the anterior opening of the vidian canal using three-dimensional (3D) computed tomography (CT) images of the bone. Methods: We reviewed 62 patients who had undergone bilateral vidian neurectomies. One hundred and twenty-four vidian canals and their surrounding anatomies were analyzed. 3D images were reconstructed using algorithms and compared with conventional two-dimensional (2D) CT images. Results: A bony prominence that overlaid the vidian canal along the sphenoid sinus floor was found in 60 (48.39%) canals. Pneumatization of the pterygoid process was observed in 45 sides (36.29%). No significant discrepancy was found in detecting these variances between the 2D and the 3D images. The presence of a surgically favorable gap between the palatine and the sphenoid bone was seen in 25 sides (20.16%) without significant association with pterygoid process pneumatization or vidian canal protrusion. This gap was not identified on the 2D CT scans. Conclusion: 3D CT reconstruction images of bone provide superior delineation of the gap between the palatine and the sphenoid bone, which is a critical variation for vidian neurectomy. This useful method may contribute to better prediction and guidance of the surgical approach to the vidian canal and pterygopalatine fossa.