Purpose: To define injection index (II) and assess its impact on visual acuity (VA) in pigment epithelial detachment from age-related macular degeneration over 5 years.
Methods: Injection index is defined as the mean anti-vascular endothelial growth factor injections per year from presentation. A retrospective study of 256 eyes in 213 patients was performed. Patients were stratified by II (high: ≥9, low: <9).
Results: Baseline characteristics showed no differences across II groups. Mean (range) follow-up, in years, was 5.02 (1.04-12.74) for all patients. 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. Linear regression analysis showed a gain of 0.5 approxETDRS letters with each additional injection per year.
Conclusion: Increased II was associated with better mean VA, suggesting that long-term continuous vascular endothelial growth factor suppression may improve VA in eyes thought to carry poor prognoses.