Short-term efficacy of photobiomodulation in early and intermediate age-related macular degeneration: the PBM4AMD study

Abstract

Abstract Objectives This independent prospective study evaluated the short-term effects and safety of photobiomodulation (PBM) in early and intermediate age-related macular degeneration. Methods patients were treated with PBM in one eye. Functional parameters and drusen volume were measured at one (W4), three- (W12) and six-months (W24) after PBM. Results The study included 38 subjects who completed the PBM protocol. Two patients developed macular neovascularization during the study period. Best corrected visual acuity improved from 77.82 ± 5.83 ETDRS letters at baseline to 82.44 ± 5.67 at W12 (p < 0.01), then declined to 80.05 ± 5.79 at W24 (p < 0.01 vs. baseline). Low luminance visual acuity showed a similar pattern, improving from 61.18 ± 8.58 ETDRS letters at baseline to 66.33 ± 8.55 at W12 (p < 0.01), and decreasing to 62.05 ± 9.71 at W24 (p = 0.02). Contrast sensitivity improved at W12 (20.11 ± 9.23 ETDRS letters, p < 0.01), but returned to baseline by W24 (16.45 ± 9.12, p = 0.5). Scotopic microperimetry showed a decrease in mean absolute retinal sensitivity from 9.24 ± 3.44 dB to 7.47 ± 4.41 dB at W24 (p < 0.01), while relative sensitivity decreased only at W24 (p = 0.04). Drusen volume decreased at W4 (0.018 ± 0.009 mm3, p < 0.01) and W12 (0.017 ± 0.009 mm3, p < 0.01), with a slight increase at W24 (0.019 ± 0.012 mm3, p = 0.154). Conclusions PBM resulted in temporary improvements in visual function and a reduction in drusen volume, but these effects were not sustained at six months. The long-term efficacy and impact on disease progression are uncertain, necessitating further research to confirm these findings and determine optimal patient selection.