Presence of Macular Neovascularization Associated with Slower Rate of GA Expansion

SriniVas R. Sadda, MD

New findings suggest the presence of macular neovascularization (MNV) was associated with a slower rate of geographic atrophy expansion, leading to an overall smaller area of atrophy over time.

Study investigators compared the differences in long-term progression of atrophy between neovascular and non-neovascular age-related macular degeneration.

“These findings support the hypothesis that MNV may protect against the progression of atrophy,” wrote study author SriniVas R. Sadda, MD, David Geffen School of Medicine, University of California Los Angeles.

The study investigators compared the enlargement rates of geographic atrophy over 5 years of follow-up with those of macular atrophy associated with MNV. The retrospective, longitudinal, comparative case series included a consecutive series of patients with age-related macular degeneration and GA (dry) or with MA and MNV.

Atrophic regions detected on serial registered fundus autofluorescence images were semi automatically delineated, according to investigators. It was noted that the measurements of these areas were recorded every 6 ± 3 months for the first 2 years of follow-up and at yearly intervals for up to 5 years.

The main study outcomes were the annual raw and square root-transformed rates of atrophy growth.

The study included 117 eyes of 95 patients (61 in the GA cohort and 56 in the MA cohort). Data show 100% and 38.5% of the eyes completed 2 and 5 years of follow-up, respectively.

The findings indicate the mean size of lesions at baseline was similar between the 2 groups (raw: 1.74 vs. 1.53 mm2, P = .56; square root-transformed: 1.17 vs 1.02 mm, P = .26).

Moreover, the overall enlargement rates were found to be greater for the GA cohort (raw: 1.72 vs 1.32 mm2/year, P = .002; square root-transformed: 0.41 vs. 0.33 mm/year; P = .03). The area of atrophy growth at 5 years was additionally greater for the GA cohort (raw: 8.06 vs. 4.55 mm2; P = .001; square root-transformed: 1.93 vs. 1.38 mm; P = .02).

At the 2-year mark, the estimated square root-transformed area was also significantly greater for the GA cohort (1.84 vs. 1.67 mm; P = .01).

The study, “Differences in Long-Term Progression of Atrophy between Neovascular and Non Neovascular Age-Related Macular Degeneration,” was published in Ophthalmology Retina.