PhotoBioModulation for Dry AMD

Photobiomodulation (Red Light Therapy) For Dry AMD 

Photobiomodulation (PBM) is an emerging therapy that has shown promising potential as a possible treatment for patients with nonexudative intermediate AMD. In truth, this low-level laser therapy (LLLT) technology has existed for more than 50 years, and researchers have been reviewing its potential ocular applications for at least 20 of those years. But with a CE mark issued in 2018, the completion of a major clinical trial last year, and this year’s appeal to the US Food & Drug Administration (FDA) by a manufacturer to market the technology as a noninvasive treatment option for dry AMD, PBM seems ready to shine. 

https://www.ophthalmologyadvisor.com/features/photobiomodulation-age-related-macular-degeneration/

How Photobiomodulation Works

Mechanistically, there are a multitude of ways in which photobiomodulation is hypothesized to assist in treating nonexudative AMD. It involves the use of targeted wavelengths of visible light to near-infrared (NIR) spectrum (500-1000 nm) produced by a noncoherent light source such as light-emitting diodes (LEDs) or a laser. This light induces a chemical reaction at the cellular level in the electron transport chain, specifically against an enzyme called cytochrome c oxidase within complex IV. Activation of complex IV directly increases mitochondrial activity within the cells in retinal layers such as RPE cells, ganglion cell nuclei, and inner/outer plexiform nuclei, which then promotes adenosine triphosphate (ATP) production, the cell’s major source of energy. Additionally, the NIR also decreases nitric oxide activity, which inhibits complex IV, thereby indirectly increasing complex IV activity. This then leads to improved photoreceptor function. 

Photobiomodulation has been shown to decrease the activity of inflammatory markers such as vimentin, glial fibrillary acidic protein (GFAP), and tumor necrosis factor (TNF). It also has been found to directly reduce expression of C2 and C3 complement expression within the outer retina. By these anti-inflammatory effects, PBM may downregulate the complement factor cascade, which plays a major role in the progression of AMD. 

Finally, photobiomodulation can also alter gene expression, leading to rescued mitochondrial function that then caused neuroprotective effects on blue-light damaged murine primary photoreceptors.

Photobiomodulation On Trial

The use and effectiveness of PBM for AMD has been tested in several studies. In a 2008 study, a semiconductor laser diode emitting continuous 670 nm light was given to 348 eyes in 4 treatments for more than 2 weeks. Best-corrected visual acuity (BCVA) improved significantly, but no details were provided regarding VA measures, type of AMD, or any structural parameters. 

The Toronto and Oak Ridge Photobiomodulation Study for Dry Age-Related Macular Degeneration (TORPA; ClinicalTrials.gov Identifier: NCT00940407) studied the impact of PBM on patients with intermediate AMD with VA between 20/20 and 20/200. Eighteen patients were treated with 2 transpupillary diode lasers for 18 treatments spanning 6 weeks and primary endpoints were changes in BCVA and contrast sensitivity. Statistically significant improvements were noted in BCVA and contrast sensitivity at 6 months and 1 year after treatment, while fixation stability remained unchanged. 

This was followed by the TORPA II study, which expanded on the previous study by including patients with vision worse than 20/200. Primary outcome measures were changes in BCVA and CS from baseline. Secondary efficacy endpoints included changes in optical coherence tomography (OCT) and fundus autofluorescence (FAF) at 3 months compared with baseline. At 3-month follow-up after photobiomodulation treatment, there was an average of +5.9 letter improvement, with 59.5% of patients having gained more than 1 line on the Snellen visual acuity chart. Drusen volume and thickness was also noted to be significantly reduced, but the overall central retinal thickness remained the same. 

LIGHTSITE Clinical Trials

Following this, the LIGHTSITE I (ClinicalTrials.gov Identifier: NCT02725762) trial was the first single-center randomized sham-controlled study to evaluate PBM efficacy in AMD. It used the Valeda Light Delivery System (LumiThera, Inc., USA), which emits 3 distinct wavelengths of light, including yellow (590 nm), red (660 nm), and near-infrared (850 nm) within 250 seconds in a total of 4 phases. Patients received 9 sessions of treatment within 3 to 4 weeks at baseline and after 6 months. Forty-six eyes of 30 patients with intermediate dry AMD and vision between 20/40 and 20/200 were enrolled. BCVA was noted to increase by an average of 4 letters, then declined to baseline at the 6-month follow up and was noted to once again increase after the retreatment at 6 months, followed by another decrease in BCVA to baseline at the subsequent 6-month follow-up. This suggests a possible role for the need for consistent repetitive therapy to maintain efficacy. A significant decrease in drusen volume was also noted in patients treated with PBM vs the control group.

This was followed by the LIGHTSITE II (ClinicalTrials.gov Identifier: NCT03878420) study, which further explored the efficacy of PBM in 53 eyes of 44 patients with intermediate dry AMD and BCVA between 20/32 and 20/100. This was a randomized controlled multi-center study with the primary outcome of change in BCVA between baseline at 9-month follow-up. The PBM-treated group had a significant improvement in vision (2.3 letters) and had a slower rate of growth of GA lesion size.

EyePower Red is a simple affordable device for home use, developed by the continual research of UK ophthalmologist & team.  Use for only 3 minutes preferably before 10 AM (it has an auto-shut off function) daily or several times a week to recharge your eyes.  

Using red-light therapy is only one aspect of your eye health.   Proper eye habits reducing technology screen and device usage, good stress/sleep management and making researched-backed practical dietary changes will make a difference between optimal & suboptimal/compromised eye function.

Use our link for more information and to purchase.   EyePower Red is a medical device and not available from Amazon.  Prices are in CAD (shipped from the UK, taxes and duties apply from Canada Post).

https://www.eye-power.co.uk/?aff=22

Although scientific studies have shown promising results from PBM Red light therapy, results will vary by individual.  The goal of red light therapy is meant to help slow down the progression of Dry AMD Macular Degeneration, improvement of vision is not guaranteed.  The use of red light therapy at home as a wellness device DOES NOT replace routine examinations & treatments by your eye doctor plus the need for daily balanced nutrient-dense diet, outdoor light exposure, rest/exercise, & lifestyle changes.