Retinal layer thickness analysis (ROP subject 6). (a) Profiles were averaged from 20 adjacent A-scans at seven retinal eccentricities (denoted by boxes). ILM, inner limiting membrane (vitreal–retinal interface); NFL, nerve fiber layer; GCL, ganglion cell layer; IPL, inner plexiform layer; INL, inner nuclear layer; OPL, outer plexiform layer; ONL, outer nuclear layer; ELM, external limiting membrane; CC, connecting cilium; RPE, retinal pigment epithelium; C, choroid; IS, inner segment layer; OS, outer segment layer; t, temporal; n, nasal. (b) The layers for each eccentricity (±437 μm, 0 μm represents the fovea) were measured from the edges and peaks in the profiles, which are shifted horizontally for clarity. On the vertical axis, 0 μm represents the RPE layer. Symbols represent different eccentricities. (c) The final calculated thickness measurements are shown as a function of eccentricity. The thickness is measured from the RPE for the retina and photoreceptor layers, between the ILM and OPL for the inner retina, and between the OPL and ELM for the ONL.