The Relative Position of the Optic Foramen to the Anterior Sphenoid Sinus Wall: A CT Anatomic Study

Abstract

Background: To delineate the position of the optic foramen (OTF) relative to the anterior face of the sphenoid sinus (AFS) using computed tomography (CT) scans. Objectives: This information could help surgeons to better plan orbital decompression surgery. Methods: This cross-sectional study was conducted on 80 normal CT scans (160 orbits) from the Iranian population between March 21 and September 22, 2022. The relative position of the OTF to the AFS was evaluated, and the distance between them was measured. Other measurements included the medial orbital wall length (MOWL) and the distance from the OTF and the AFS to the carotid prominence (CP). Chi-square and independent t-tests were used for data analysis. Results: In 52.5% of orbits, the OTF was positioned anterior to the AFS; it was positioned posterior in 24.3% and at the same level in the remaining 23.1%. The mean distance of the OTF to the AFS was 4.35 ± 1.378 mm when the OTF was anterior to the AFS and 4.7 ± 1.80 mm when the OTF was located posterior to the AFS. The mean distances from the OTF and the AFS to the CP were 6.74 ± 2.25 mm and 7.87 ± 2.76 mm, respectively. Conclusions: Our findings suggest that in approximately half of the subjects, the OTF is positioned anterior to the AFS. The position was symmetric in 50% of individuals.