Abstract
Purpose :
Although the outer retina is the primary area affected in age-related macular degeneration (AMD), secondary alterations in the inner retina have been suggested. To test this hypothesis, we evaluated the Ganglion Cell Complex (GCC) thickness in subjects with AMD.
Methods :
A total of 620 eyes of 310 elderly (>age 50) Amish individuals who were enrolled in a population-based study were included in this post-hoc analysis. All subjects underwent complete ophthalmic examination, optical coherence tomography (Cirrus OCT, 6x6mm, 512 x 128) and flash color fundus photography. Foveal central subfield retinal thickness, mean retinal thickness, mean macular volume, and mean thickness of the GCC were obtained using the instrument software. The color fundus images were graded according to the Beckman classification as: Stage 0 (normal), Stage 1 (normal aging), Stage 2 (early AMD), Stage 3 (intermediate AMD), and Stage 4 (late AMD). The GCC thickness between groups were compared in a pairwise fashion using t tests.
Results :
Among the 620 eyes, 408 eyes were normal, 67 eyes had early AMD, 101 eyes had intermediate AMD, and 44 eyes had late AMD. The mean age was significantly (<0.0001) lower in the normal group (62.43 years) compared to the AMD group as a whole (71.88 years). After adjusting for age, there was no significant difference in retinal thickness (p = 0.16) or retinal volume (p = 0.14) between the study groups. However, the mean GCC thickness was significantly (p < 0.05) lower in all AMD groups [early AMD: 73.94µm; intermediate AMD: 76.55µm; late AMD: 58.80µm] compared to normals (78.22 microns).
Conclusions :
Eyes with AMD show lower GCC thickness compared to normal eyes, with the most severe reduction observed in eyes with late AMD. Alterations in the inner retina during the progression of AMD warrant further study.
This is a 2021 ARVO Annual Meeting abstract.