Survey Anatomical Features and Related Factors of the Sphenopalatine Foramen on Computed Tomography

The aim of the research is to define anatomical features of the sphenopalatine foramen (SPF) and be related to the SPF on computed tomography (CT) such as shape, location, size of the SPF, the appearance of the ethmoidal crest, and the distance from SPF to some landmarks in the nasal cavity. As a result, surgeons could quickly determine the SPF location in transnasal endoscopic sphenopalatine artery ligation (TESPAL). A cross-sectional study was conducted. This study was carried out at Cho Ray hospital from August 2019 to June 2020. Image data from 55 patients who had been indicated sinuses CT. Results show that the SPF had a wide range of shapes: oval (20.9%), triangle (19.1%), circle (18.2%), racket shape (7.3%), hourglass shape (6.4%), and other shapes. In the anteroposterior dimension, the mean SPF was 5.72 ± 1.22 mm. In the craniocaudal dimension, the mean SPF measured 5.62 ± 1.99 mm. The SPF was mainly located in the superior meatus and in the transition between the middle and superior meatus. The most reliable anatomical landmark to find the SPF was the ethmoidal crest with an appearance rate of about 95.5%. The mean distances from SPF to anterior nasal spine, nasal floor, nasal septum, maxillary line, anterior head of the middle turbinate, choanal arch, and base lamella were 57.04 ± 3.11, 24.71 ± 2.90, 11.26 ± 2.09, 34.93 ± 2.07, 32.69 ± 3.30, 8.82 ± 1.65, and 8.07 ± 1.28 mm, respectively. CT scan images in this study can provide information about anatomical features of the SPF, which contribute to the quick and efficient identification of the SPF before and during TESPAL.