Purpose: To study the natural history and anatomic characteristics of geographic atrophy (GA) in eyes with dry age-related macular degeneration (dAMD) compared to fellow eyes with macular atrophy and concurrent neovascular AMD (nAMD) treated with anti-vascular endothelial growth factor (VEGF) injections.
Methods: This is a single-center, retrospective chart review. Data were recorded at two time points (#1 and #2) one year apart. Two independent graders reviewed the images to measure atrophy area and grade it based on the Consensus on Atrophy Meeting group criteria. Difference in atrophy area between the two time points was calculated. A square root transformation (SQRT) was also performed to report the change in atrophy progression.
Results: 208 eyes of 104 patients were included: 104 eyes had dAMD and 104 fellow eyes had nAMD. Mean (SD) atrophy area was 14.05 (9.96) mm2 in dAMD eyes and 14.14 (9.26) mm2 in nAMD eyes (p= 0.95) at time point #1, and 16.92 (10.83) mm2 in dAMD eyes and 17.35 (11.03) mm2 in nAMD eyes (p= 0.78) at time point #2. Mean (SD) atrophy growth rate was 3.08 (2.52) mm2/year in the nAMD eyes and 2.77 (1.88) mm2/year in the dAMD eyes (p= 0.32). Using the SQRT, the growth rates were 0.40 (0.24) mm/year in nAMD and 0.38 (0.22) mm/year in dAMD (p= 0.55).
Conclusion: GA in eyes with dAMD and macular atrophy in fellow eyes with nAMD exhibit similar growth rates, suggesting a high degree of concordance and potentially a similar mechanism of atrophy development and progression.
Keywords: age related macular degeneration; anti-vascular endothelial growth factor; geographic atrophy; macular atrophy.