Analysis of sexual dimorphism in human eye orbits using computed tomography

Abstract

A plethora of anthropological studies have been undertaken on the skull, including many analyses of sexual dimorphism. Sexual dimorphism reflected in the eye orbits has not always demonstrated consistent or reliable results. However, recent studies (Pretorius, Steyn, & Scholtz, 2006; Ji et al., 2010) suggest some positive results utilizing geometric morphometrics to predict sex. Utilizing 97 post-mortem CT (computed tomography) scans, established morphological and metric techniques for sex determination were assessed from 3D rendered models of the crania. In addition, landmark data were collected on the orbital margin to evaluate the accuracy of sex determination using geometric morphometric techniques. Traditional methods demonstrated poor levels of accuracy for prediction of sex, however, utilizing generalised procrustes analysis and discriminant function analysis on 3D landmark data resulted in 94.95% overall accuracy. Application of recent methodological advances, including geometric morphometrics, should continue to be developed as it increases the ability to assess sexual dimorphism which will allow for greater identification of unknown remains.