Normal Retinal Nerve Fibre Layer (RNFL) Thickness in Indian Population: Optical Coherence Tomogram

Abstract

We determine normal retinal nerve fibre layer (RNFL) in the normal North Indian population as measured by optical coherence tomography (OCT). It provides cross-sectional observational study. Twenty normal subjects from 10 to 45 yrs old (40 study eyes) have been selected as participants for this study. As a method, peripapillary fast RNFL scans performed by FD-OCT with a nominal diameter of 3.46 mm centered on the optic disc were performed on both eye of each subject. The RNFL thickness varies from 100 to 315 µm from periphery or ora serrata to fovea. The mean RNFL at fovea, at inner macula, at outer macula and at ora serrata were 235.95 ± 21.91, 304.84 ± 22.12, 286.25 ± 20.57 and 111.64 ± 12.6 respectively. Retinal nerve fiber layer thickness, as measured by OCT varies significantly with age, ethnicity, axial length and optic disc area. These variables may need to be taken into account when evaluating patients for diagnosis and follow-up of glaucoma, myopia induced glaucoma and myopia particularly at the lower boundary of the normal range.

Keywords: Retina, Optical Coherence Tomography (Oct), RNFL, North Indian, Macula