Assessment of the effect of age on macular layer thickness in a healthy Chinese cohort using spectral-domain optical coherence tomography

Background: To determine the effect of age on the thickness of individual retinal and choroidal vascular layers in the macula in an ophthalmologically healthy Chinese cohort by using spectral-domain optical coherence tomography (SD-OCT). Methods: In all, 525 health eyes of 525 subjects were examined with SD-OCT. The instrument automatically obtained the regional retinal thickness of 8 layers. Subfoveal choroidal vascular layers' thickness was measured using enhanced depth imaging mode. The correlation of age with layer thickness measurements was determined. Results: No age-associated variation was found on retinal thickness (RT) in the fovea; however, the foveal thickness of outer nuclear layer (ONL), retinal pigment epithelium (RPE) and vascular sublayers of the choroid decreased significantly with aging in this area (P < 0.05, respectively). Significant age-related reduction was seen in RT in the pericentral and peripheral rings (P < 0.05, respectively). The significant variation in thinning of the ganglion cell layer, inner plexiform layer, and ONL with aging is thought to be the main determinant of these results (P < 0.05, respectively). On the contrary, the RPE layout showed age-related thickening (P < 0.05, respectively) in the pericentral and peripheral regions. Conclusions: The thickness of individual layers of the macula may be determinants of the age-related variations observed in the ophthalmologically healthy Chinese cohort, as assessed by SD-OCT examination.