The Morphometric Relationship Between the Infraorbital Foramen and Key Midfacial Anatomical Landmarks

Objective: The infraorbital foramen (IOF) is an important anatomic landmark that facilitates anesthesia and surgical applications in the midface. Infraorbital nerve block is commonly used to provide regional anesthesia during procedures involving the midface and paranasal sinuses. This study aims to describe the morphometric relationships between the infraorbital foramen and key anatomic landmarks in the face. Methods: Three-dimensional reconstruction computed tomography images of 316 individuals (female = 163, male = 153) aged 18-86 were included in the study. These individuals were divided into five age groups. The IOF dimensions and distances to selected midfacial landmarks were measured. Results: The mean age of the 316 individuals participating in the study was found to be 40.19±15.38. The IOF dimensions and the distances from the IOF to the piriform aperture, midline, alveolar border, anterior nasal spine, and nasion were found to be significantly higher in men. In women, there were statistically significant differences in the distances from the IOF to the infraorbital margin, midline, and alveolar border according to the sides. The distance from IOF to the midline was found to be significantly greater on the right side of men. It was observed that the transverse diameter of the IOF decreased with increasing age. In addition, the distance between the IOF and the infraorbital margin was shorter in individuals aged over 60 years. A strong positive correlation was found between the distances from the IOF to the midline and the piriform aperture (r=0.75). Conclusion: Because the IOF is closely associated with neurovascular structures, determining its location is crucial. The morphometric values ​​presented in this study may help determine the origin of the infraorbital nerve and the location of the IOF. The localization of the IOF and its anatomical variations should be carefully evaluated before surgical navigation, implant planning, and the administration of anesthesia.