The Analysis of Intra-retinal Layers with Automatic Optical Coherence Tomography Segmentation in Healthy Subjects

Abstract

Aims: To give normative databases of each retinal layers on OCT images in the healthy Caucasian population in Turkey and investigate the relevance of the data with factors such as age, gender, axial length and refraction.
 Study Design: Prospective, cross sectional, descriptive study.
 Place and Duration of Study: Department of Ophthalmology, Faculty of Medicine, Kirsehir Ahi Evran University, Kirsehir/TURKEY. Between September 2017 and March 2018.
 Methodology: 133 participants underwent full ophthalmologic examination and spectral domain OCT imaging (Spectralis, Heidelberg Engineering, Germany). After the automatic segmentation, central 1 mm and 1-3 mm superior, inferior, nasal and temporal thicknesses of retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), retina pigment epithelium (RPE), inner retinal layers (IRL), outer retinal layers (ORL) and total retina thickness (TRT) analyzed with respect to age, gender, axial length and refraction (spherical equivalent).
 Results: Central 1 mm INL, ONL, ORL, IRL and TRT and four quadrants of pericentral 1-3 mm thicknesses of RPE had positive correlation with the age. All the sections of total retina, RNFL, GCL, IPL, INL, ONL and IRL thicknesses were significantly thicker in males compared to females. The thicknesses of all RNFL sections and central 1 mm circle thicknesses of TRT, IPL, INL, OPL, RPE and IRL had positive correlation with the axial length.
 Conclusion: A normative database for thicknesses of intra-retinal layers in Turkish population was presented in the study and significant impacts of the age, gender and axial length were presented.