Study of Prevalence and Topography of Ethmoidal Foramina in Adult Dry Skulls Along With Clinical Implications

Ethmoidal foramina are located in the medial wall of the orbit along frontoethmoidal suture. These foramina transmitting ethmoidal neurovascular bundles vary in number and topography in various ethnic groups. The precise location and number of these foramina are important while dealing with various surgeries involving medial orbital wall. Aim of study is to highlight the incidence, number, topography of ethmoidal foramen and correlate with clinical implications. The study was conducted in the Department of Anatomy using 105 right-sided and 105 left-sided orbits. The number of foramina were counted by visual inspection, and distance between these foramina along with distances of these foramina from optic canal were measured, and statistical analysis was carried out using Microsoft Excel 2019. The ethmoidal foramina with range of 0 to 5 were observed. The ethmoidal foramina were absent in 10% of orbits with 12.5% on right-sided orbits and 7.6% on left-sided orbits. Maximum number of 5 ethmoidal foramina were detected in 2.4%, 4 ethmoidal foramina in 6.7%, 3 ethmoidal foramina in 20.95%, 2 ethmoidal foramina in 54.3% and single ethmoidal foramina in 5.7% of orbits. The mean distances between anterior-middle, middle-posterior, anterior-posterior EF and posterior ethmoidal foramina-optic canal were 5.8 ± 0.8 mm, 5.2 ± 0.9 mm, 10.5 ± 0.9 mm and 5.1 ± 0.8 mm, respectively. The number and precise location of ethmoidal foramina are essential during various interventions involving orbit such as medial orbital wall fractures, the orbital decompression, to prevent complications.