Can Light Therapy Help Dry Macular Degeneration? What the LIGHTSITE Trials Found

Age-related macular degeneration (AMD) is a leading cause of vision loss, and the "dry" (non-exudative) form has historically had few treatment options. A series of randomized, sham-controlled trials — nicknamed LIGHTSITE — has tested whether multiwavelength photobiomodulation can help.

What the research looked at

The LIGHTSITE II trial randomized 44 subjects (53 eyes) with intermediate dry AMD to real or sham multiwavelength (590/660/850 nm) light therapy delivered via a clinical device, tracking visual acuity and geographic atrophy over 9 months. LIGHTSITE III followed with a larger group — 100 subjects (148 eyes) — over 13 months, using the same real-versus-sham design.

What they found

In LIGHTSITE II, treated eyes gained about 4 letters of best-corrected visual acuity on a standard eye chart versus roughly 0.5 letters for sham (p=0.02), and geographic atrophy grew 20% more slowly in the treatment group. LIGHTSITE III confirmed the pattern at a larger scale: treated eyes gained a mean of 5.4 letters versus 3.0 for sham, with 55% of treated eyes gaining 5 or more letters compared to 40.8% of sham eyes — and new geographic atrophy developed in just 1.1% of treated eyes versus 9.8% of sham eyes.

What this means in practice

Two independent, sham-controlled trials from the same research program both found measurable vision and disease-progression benefits from light therapy in dry AMD — a condition with very limited treatment options otherwise. This is specialized, clinically supervised light therapy for a specific eye condition, not a general claim about eye health, and anyone with AMD should be under an ophthalmologist's care regardless.