Sexual dimorphism of the adult human retina assessed by optical coherence tomography

Abstract

Sexual dimorphism in the human visual system is a well-established phenomenon, and recent research has unveiled possible connections between gonadal hormones and the retina status. In the literature, the findings are quite diverse and inconclusive results have been reported as well. In the study herein, texture analysis was applied to computed optical coherence tomography (OCT) fundus images to identify differences between female and male healthy adult controls at the six neuroretinal layers. Furthermore, younger and older groups were formed to assess differences across the adult lifespan. Besides local and global texture features, the thickness of each retinal layer at study was also analysed. The vast majority of the differences between female and male groups were found from the ganglion cell layer (GCL) to the outer plexiform layer (OPL), with the retinal nerve fibre layer (RNFL) layer being the least distinct one. For the sub-study by age, the younger group show similar results as those for the entire population, except for the RNFL. On the other hand, the older group presents minute differences between female and male subjects. These findings suggest that studies should be well balanced by sex, and particular care should be taken in the age span of the study groups. In the present study, we also demonstrate that texture and thickness are independent, for the most part, that thickness conveys the least information, and that texture is a strong biomarker candidate for eye and central nervous system status in health and disease.