Analysis of bony landmarks of the orbit “an aid in the localisation of the orbital process of the palatine bone”

Objectives: In case of repair of an orbital floor fracture, adequate support of the reconstruction material is essential. Since the orbital process of the palatine bone as part of the posterior ledge remains intact in most trauma cases, this bony process plays an important role in the support posteriorly. The aim of the study is to determine mean distances between specific landmarks in the orbit in men and women, with a special emphasis on localisation of the orbital process of the palatine bone. Methods: Four landmarks were identified retrospectively on computed tomography (CT) scans of 100 adult Caucasian patients (50 males and 50 females): top of the infraorbital margin superior to the infraorbital foramen (point A), top of the orbital process of the palatine bone (point B), anterior bony part of the superior orbital fissure (point C), and ventro-lateral aspect of the bony entrance of the optic canal (point D). Distances between these points were measured. Findings: Mean distances between the orbital rim (A) and orbital process of the palatine bone (B) were 32.5 mm in females and 33.7 mm in males. Males had significantly larger bony orbits than females. Conclusions: These measurements can enable a safer and more predictable surgical approach to the orbit, which may help reduce the risk of damaging important neighbouring structures. It may also help adequately localise the posterior ledge, specifically the orbital process of the palatine bone thereby ensuring a more precise reconstruction of the orbital floor and promoting a better surgical outcome.