Correlation between retinal and choroidal thickness in normal emmetropes

Context: An objective and quantitative analysis of the normal choroid and retina relation is required for a better understanding of changes that occur in retinal and choroidal diseases. Aims: This study aimed to evaluate choroidal thickness (CT) and corresponding retinal thickness (RT) using enhanced depth imaging mode of spectral-domain optical coherence tomography (SD-OCT) in normal emmetropic eyes. Methods: One hundred and six eyes of healthy, nearly emmetropic eyes of volunteers were examined by Spectralis OCT. Manual measurements of CT were done under the fovea and on the vertical and horizontal line scans at the ETDRS 1 and 3 mm circles. RT was measured in the center foveal subfield and at the same locations of CT measurements. Statistical Analysis Used: Data were analyzed using IBM SPSS software package version 20.0 (SPSS, Inc., Chicago, IL, USA). Results: With a mean age of 50.3 ± 16.5 years, the mean subfoveal choroidal thickness (SCT) was 297.5 ± 86.2 μ while the mean central RT was 264.3 ± 15.9 μ. The mean CT was thinnest at the nasal location but without statistical significance and SCT was higher in males than females. Significant and correlated age-related thinning was observed in both retina and choroid at all locations, except the fovea, where these changes were significant but not correlated. Conclusions: CT has an age-related thinning pattern that correlates with age-related retinal thinning in extrafoveal macular locations. In addition, age can be used as a guide in predicting the normal SCT in emmetropes.