Microscopic anatomy of the infraorbital canal, nerve, and foramen

Abstract

OBJECTIVE: We performed this study to investigate the morphologic and topographic anatomy, and variations of the infraorbital canal (IOC), infraorbital nerve (ION), and infraorbital foramen (IOF). STUDY DESIGN AND SETTING: This study was performed at the Anatomy Department of Ankara University School of Medicine between 1999 and 2000. The morphometry of these anatomic areas on cadaver heads were studied microscopically. The morphologic and topograpic anatomies of IOC, ION, and IOF were carried out microscopically with ×25 to ×40 magnification on 10 cadaver heads (20 sides). RESULTS: We found the shape of the IOF as oval in 30% (6 sides), round in 40% (8 sides), and semilunar in 30% (6 sides) of the cadaver heads. We detected the IOF as single in 90% (18 sides), double in 5% (1 side), and triple in 5% (1 side) of the cases. We determined a complete roof (we called it as "canal") in 50% of cases and groove plus canal in 50% of the heads. The mediolateral relationship of the vessels to the nerve while emerging from the IOF was investigated, and the artery was always found in a mediosuperior position and the vein was inferior to it. In all specimens, the ION was found to be consisting of 3 to 8 fascicles interwoven with the artery and the vein in the loose connective tissue sheath. CONCLUSION: A detailed knowledge of the anatomic morphometry of this area is necessary for a surgeon while performing maxillofacial surgery and regional block anesthesia. Anatomic variations on this area may take place and a surgeon must take this into consideration so as to increase the surgical success.