Optical Coherence Tomography–Derived Measurements of the Optic Nerve Head Structure of Aboriginal and Torres Strait Islander Children

Abstract

Purpose: To examine the optic nerve head (ONH) characteristics of visually normal Aboriginal and Torres Strait Islander children and non-Indigenous Australian children. Précis: This study demonstrated significant differences in optic nerve head characteristics in Aboriginal and Torres Strait Islander compared to non-Indigenous children which has implications for glaucoma risk and diagnosis in Aboriginal and Torres Strait Islander populations. Patients and Methods: Spectral domain optical coherence tomography (OCT) imaging was performed on the right eye of 95 Aboriginal and Torres Strait Islander children and 149 non-Indigenous Australian children (5–18 years). Horizontal and vertical line scans, centred on the ONH were analysed to determine the dimensions of the ONH (Bruch’s membrane opening diameter (BMOD)), optic cup diameter, Bruch’s membrane opening minimum rim width (BMO-MRW), and the peripapillary retinal nerve fibre layer (RNFL) thickness). Results: The vertical but not horizontal BMOD of Aboriginal and Torres Strait Islander children was significantly larger than non-Indigenous children (mean difference: 0.09 mm, P = 0.001). The horizontal (mean difference: 0.12 mm, P = 0.003) and vertical cup diameter (mean difference: 0.16 mm, P < 0.001) were also significantly larger in Aboriginal and Torres Strait Islander children, as were the horizontal and vertical cup-to-disc ratios (both P < 0.01). Aboriginal and Torres Strait Islander children also had a significantly thinner BMO-MRW in the superior, nasal and temporal meridians (all P < 0.001). Peripapillary RNFL thickness did not differ between groups. Conclusions: Differences exist in the ONH structure between Aboriginal and Torres Strait Islander children and non-Indigenous children which may have implications for detection and monitoring of ocular disease in this population and highlights the need to extend this research to the adult population.