A Morphometric Analysis of Orbit in Dry Adult Human Skulls and Its Clinical Importance

Background:The bony orbits are skeletal cavities located on either side of the nose. They house the eyes, the paired peripheral organs of vision. The orbit also contains extraocular muscles, the optic, oculomotor, trochlear, and abducent nerves and branches of the ophthalmic and maxillary divisions of the trigeminal nerve; the ciliary parasympathetic ganglion; the ophthalmic vessels; and the nasolacrimal apparatus. Aim & Objectives: The aim of this study is a morphometric study of the orbit in dry human adult skulls of the North Indian population. The objective is to study the various parameters of orbit in human dried skulls and compare them with other studies. The following parameters are measured: 1. Orbital height (OH) 2. Orbital breadth (OB) 3. Orbital index (OI) 4. Interorbital distance (IOD) 5. Biorbital distance (BOD). Materials and Methods: 50 adult dry skulls (100 orbits) with 0.01mm accuracy on both the right and left sides were measured using digital verniercalipers. The skulls were obtained from the bone bank of the department of anatomy at Rama Medical College, Hospital, and Research Centre, Pilkhuwa, Hapur, and K. M. Medical College & Hospital, Mathura.Orbital height (OH) and orbital breadth (OB) of both sides were measured, and orbital index (OI) was calculated by applying the formula OI = OH/OB x 100. All the data obtained were statistically analyzed and tabulated. The quantitative morphometry of right and left orbital cavities was compared by an independent sample't' test. Results: The mean orbital heights for the right and left sides were 34.67 ± 2.50 mm and 34.40 ± 2.32 mm, while their breadth was 39.75 ± 3.43 mm and 39.31 ± 3.26 mm, respectively. The mean orbital index calculated was 86.45 ± 9.67 mm on the right and 87.56 ± 7.45 mm on the left side. There was no significant difference between the right and left sides of the orbital parameters. The mean biorbital distance and interorbital distance were 98.23 ± 6.84 mm and 20.86 ± 2.42 mm, respectively. The majority of orbits measured were of the mesoseme category. Conclusion: Regional studies on the orbital index will provide useful data for clinical and surgical treatment for patients in ophthalmology, oral and maxillofacial surgery, and neurosurgery.