Photobiomodulation induces drusen regression with improvements in visual acuity and contrast sensitivity in subjects with dry AMD

Abstract

Purpose : The aim of this study was to assess functional and anatomical benefits of Photobiomodulation (PBM) using measures of best corrected visual acuity (BCVA) and contrast sensitivity (CS) plus changes in retinal drusen volume.

Methods : 42 eyes of 24 subjects with dry AMD, AREDS categories 2, 3, and 4 who had consented and been treated with PBM were evaluated for ETDRS BCVA, CS and changes in drusen volume on SD-OCT with linear mixed effects analyses.
Treatment parameters: LED light comprising of Red (670nm), Yellow (590nm) and Infra-red (790nm) had been applied to the subjects eyes over a 3 week course in an optimised regime.

Results : A statistically significant improvement of mean ETDRS BCVA: +5.9 letters (P<0.001) and mean CS: +0.11 log units at 3 cycles per degree (P=0.02) was seen immediately following the treatment and maintained for 3 months.
Significant mean Drusen Volume reduction of 0.024 mm³ (P<0.001) and Central Drusen Thickness reduction of mean 3.78 µm, (P < 0.001) was seen immediately following treatment and maintained for 3 months.
Please see figures 1 and 2.

Conclusions : This is the first instance of statistically significant improvement in both functional (BCVA and CS) and objective anatomical (OCT drusen volume and central drusen thickness reduction) findings reported in dry AMD subjects with PBM therapy. The results indicate a sustained disease modifying effect following a short non invasive treatment course.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

 

This shows the percentage of eyes achieving up to one, two and three ETDRS lines immediately post treatment.

 

This shows a representative example of an eye categorised as AREDS 3 with mainly convex, homogenous and low reflective drusen larger than 125 µm. Baseline (Top) shows a drusen volume of 0.39 mm³ with a mean central 1 mm drusen thickness of 29 µm. Black numbers indicate the mean drusen thickness of each ETDRS subgrid and red numbers indicate the corresponding drusen volume (mm³). Bottom: Follow up examination at 1 month. Overall drusen volume as well as mean central drusen thickness has significantly decreased without new formation of GA or disruption of the photoreceptor layers.