Abstract: To provide an anatomical basis for vidian neurotomy by endonasal endoscopy. MethodsWith the assistant of a metal stylet and X-ray, the pterygoid canal and its track and orientation were dissected and observed on 56 sides of a skull. ResultsThe average length of the pterygoid canal was 16.03±1.48 mm and from the lower border midpoint of the nose bone to the anterior openings of the pterygoid canal was 60.70 ±8.86mm. Spacing between the twin anterior openings of the pterygoid canal was 27.56±3.11mm and between the twin back opening of the pterygoid canal was 34.41±3.37mm. The angle of the double pterygoid canal was 23.9±2.25°. The average length from the front nose thorn to the anterior opening of the pterygoid canal was 58.16±5.80mm and the average angle between their line and the pterygoid canal was 33.50±3.52°. The average angle between the pterygoid canal and the Frankfurt horizontal plane was 6.86±3.37° and between the pterygoid canal and the nose fundus plane was 9.68±4.60°. ConclusionThe resultant data attained in this research can be used as momentous parameters for vidian neurotomy by nostril endoscopy.

Key words: Vidian nerve, Rhinitis, Pterygoid canal, allergic, perennial, Anatomy