Photobiomodulation reduces drusen volume and improves visual acuity and contrast sensitivity in dry age‐related macular degeneration

PURPOSE To evaluate the efficacy of photobiomodulation (PBM) treatment for patients with dry age-related macular degeneration (AMD). METHODS Assessments on 42 eyes with dry AMD (age related eye disease study (AREDS) 2-4) were conducted. Multiwavelength light emitting diode (LED) light comprising of yellow (590 nm), red (670 nm) and near-infrared (790 nm) bandwidths was applied to subjects' eyes for a treatment course of 3 weeks. Outcome measures were changes in best-corrected visual acuity (BCVA), contrast sensitivity (CS), drusen volume and central drusen thickness. RESULTS Significant improvement in mean BCVA of 5.90 letters (p < 0.001) was seen on completion of the 3-week treatment and 5.14 letters (p < 0.001) after 3 months. Contrast sensitivity improved significantly (log unit improvement of 0.11 (p = 0.02) at 3 weeks and 3 months (log unit improvement of 0.16 (p = 0.02) at three cycles per degree. Drusen volume decreased by 0.024 mm3 (p < 0.001) and central drusen thickness was significantly reduced by a mean of 3.78 μm (p < 0.001), while overall central retinal thickness and retinal volume remained stable. CONCLUSION This is the first study demonstrating improvements in functional and anatomical outcomes in dry AMD subjects with PBM therapy. These findings corroborate an earlier pilot study that looked at functional outcome measures. The addition of anatomical evidence contributes to the basis for further development of a non-invasive PBM treatment for dry AMD.