Inner retinal layers' thickness changes in relation to age in healthy eyes

Abstract

AbstractPurpose: Characterizing the structural change of the macula produced by aging in healthy eyes is essential to discriminate physiological alterations typical of aging from other pathological signs. In this study, macular thicknesses measured by spectral‐domain optical coherence tomography (SD‐OCT) were characterized in young, middle‐aged, and older subjects without ocular pathology.Methods: The study design was observational cross‐sectional and was conducted in 154 eyes of 154 healthy participants between 20 and 80 years (mean 44 ± 18 years of age) divided into three age groups: young (20–39), middle‐aged (40–59) and older (60–80). Macular thicknesses were measured through SD‐OCT using the grid employed of the Early Treatment Diagnostic Retinopathy Study (ETDRS). We analysed five sub‐fields: the central fovea and the four regions (temporal, nasal, superior, inferior) of the parafoveal ring. Mean macular thicknesses were recorded for each of the three retinal segmentations: the inner retinal layer (IRL), the outer retinal layer (ORL) and the total retinal layer. Comparisons of macular thicknesses across age groups were performed.Results: Mean total and ORL thicknesses were not significantly different in the central subfield and each region of the parafoveal ring of the ETDRS grid (temporal, nasal, nasal, inferior and overall) for the three age groups. However, age had a significant effect on IRL thickness in each region of the parafoveal ring. In the superior, nasal and inferior regions, mean IRL thicknesses decreased significantly in the older age group compared to the other age groups (all p < 0.0001). In the temporal region, mean IRL thickness decreased with age and was significantly different for each of the three age groups (p < 0.0001).Conclusions: Age did not significantly influence total and ORL thicknesses in the macula. However, the macular thickness of the IRL decreased in subjects older than 60 years of age.