Abstract
Purpose :
To develop age-specific ganglion cell complex (GCC) thickness standards, and to underscore age-related variations in superior versus inferior peripapillary GCC thickness and the interplay behavior of inner retinal layers from the choroidal layer.
Methods :
OCT images were acquired by swept-source OCT with a central wavelength of 1060 nm, running at 100 kHz with a 12×12 mm scan pattern. The choroidal slab was segmented by a validated attenuation-corrected algorithm while retinal nerve fiber layer (RNFL) and GCC slabs were segmented by a validated multilayer algorithm. The segmentation errors were corrected manually when necessary. Three thickness maps were generated: choroidal thickness (CT), RNFL thickness, and GCC thickness (Fig.1). Regional distributions of CT, RNFL, and GCC thickness were then analyzed using the concentric 2.5, 5.0, and 11mm circle centered on fovea. Age-related changes in RNFL, and GCC thickness were assessed. Correlations between regional RNFL, GCC thickness, and CT were evaluated.
Results :
We analyzed 143 healthy eyes aged 20 to 90 years. A statistically significant decline in GCC thickness with age was observed across all three measured circles (all P<0.01). In contrast, no significant reduction in RNFL thickness was shown with age. Additionally, a strong correlation was found between RNFL and GCC thicknesses in all three circles (all P<0.001). However, neither RNFL nor GCC thickness showed a significant association with CT (all P>0.05). Interestingly, a notable disparity was observed in GCC thickness between superior and inferior arcade (P<0.001), but not in peripapillary RNFL thickness (P=0.637).
Conclusions :
The GCC thickness standardization would involve establishing normal ranges for each age group, aiding in the identification of abnormal thinning or thickening indicative of pathology like glaucoma or macular degeneration. Additionally, the distinct patterns of age-related changes in superior versus inferior peripapillary GCC thickness, and the lack of interaction between the inner retinal layers and the choroidal layer, highlight the need for age-adjusted standards in retinal diagnostics and indicates that these regions may be affected differently by various diseases or age-related changes.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.