Determining orbital volumes of sheep, goats and gazelles via computed tomography.

Abstract

Orbital volume refers to the sum of bulbus oculi volume and orbital cavity volume. Scientists use orbital volume as a guide to diagnose, treat and prognose various eye diseases such as thyroid eye disease and enophthalmos. This study aims to examine the orbital volumes of sheep, goats and gazelles to demonstrate homotypic variations and interspecific differences between them. Crania of six male tuj sheep, five male hair goats and five male gazelle were used in this study. The crania were scanned using a 64-detector multi-detector computed tomography with a slice thickness of 0.625mm at 80kV, 200 MA and 639 mGy. The cross-sectional images were stored in DICOM format and then transferred to MIMICS 20.1 software. Afterwards, models were made by establishing the orbital borders on the cross-sections. Volume values were calculated based on the models. No homotypic variation was found between the right and left volumes within the species (p > 0.05). A statistically significant difference was observed in terms of interspecific right and left orbital volumes between sheep and gazelles (p < 0.05). It was concluded that the orbital parameters of the sheep, goats and gazelles in the same family help reveal their differences in the visual anatomy of these species and provide reference data for clinical diagnosis, treatment and the prognosis follow-up of ocular diseases in animals.