An increased injection index (II) is associated with better mean visual acuity (VA) in 5-year follow-ups for patients with pigment epithelial detachment from age-related macular degeneration (AMD), according to a study published in Retina. The findings suggest that long-term, continuous vascular endothelial growth factor (VEGF) suppression may improve VA for patients with poor prognosis.
The multicenter, retrospective study of 256 eyes in 213 patients looked at II (defined as mean anti–VEGF injections per year) from presentation, with patients stratified by II (high: 9, low: 9).
Researchers found that baseline characteristics had no differences across II groups. For all patients, mean (range) follow-up, in years, was 5.02 (1.04–12.74). Mean logMAR VA (Snellen VA) were: 0.60 (20/80) and 0.56 (20/73) at baseline; 0.52 (20/66) and 0.59 (20/78) at year 1; 0.45 (20/56) and 0.67 (20/94) at year 2; 0.38 (20/48) and 0.66 (20/91) at year 3; 0.41 (20/51) and 0.89 (20/155) at year 4; and 0.35 (20/45) and 0.79 (20/123) at year 5 for the high and low II groups, respectively. With each additional injection per year, linear regression analysis showed a gain of approximately 0.5 ETDRS letters.
“Importantly, this is the first and largest study to evaluate long-term, 5-year, visual outcomes of eyes with PED/AMD,” according to the investigators. “The current study showed a statistically significant difference in mean VA in patients with PED/AMD at years 2 to 5 of follow-up, with patients in the high II group having improved VA and patients in the low II group having worsened VA. Our study also found a positive correlation between VA and injections per year, with a gain of 0.5 letters per additional injection per year, including in years 3, 4, and 5, representing the first suggestion that eyes with PED/AMD can demonstrate improved function beyond 2 years.”
The study’s limitations include its retrospective design, conversion of Snellen to logMAR VA, inclusion of low vision measurements into the analyses, loss of patients in each II group, inclusion of a heterogeneous population of choroidal neovascularization (CNV) types, inclusion of non-naive eyes with unknown II status, risk of developing RPE tears, and potential confounders, according to study authors.
Gui W, Au A, Rabina G, et al. Pigment epithelial detachment in age-related macular degeneration: long-term visual acuity may improve with higher injection index. Retina. 2021;41(11):2229-2235. doi:10.1097/IAE.0000000000003224