Posterior Border of the Deep Lateral Orbital Wall—Appearance, Width, and Distance From the Orbital Rim

Abstract

To reveal the appearance of the posterior border of the deep lateral orbital wall and to examine the width of the posterior border and distance from the lateral orbital rim to the posterior border. Twenty-seven postmortem orbits (17 right, 10 left) of 17 Asians aged from 57 to 101 years at death (average, 81.6 years) fixed in 10% buffered formalin were examined. After removing the deep lateral orbital wall except for its posterior border, we first observed the appearance of the posterior border, and then confirmed its thinness by using a light source behind the posterior border. Next, the width of the posterior border and distance from the orbital rim to the posterior border were measured at a position 8 mm superior to the inferior orbital rim. The posterior border of the deep lateral orbital wall was very thin. The width of the posterior border was almost constant at each level. The light was strongly visible through the bone of the posterior border. The average width of the posterior border was 17.6 mm OD and 17.3 mm OS, whereas the average distance from the orbital rim to the posterior border was 32.9 mm OD and 32.7 mm OS. Lateralities were not demonstrated in both categories. This information regarding the true appearance of the posterior border and its width and distance from the orbital rim will ensure that surgeons can safely and confidently perform deep lateral orbital wall decompression.