The study published in the Journals of Gerontology is the first of its kind in humans. Researchers hope it could signal the dawn of new affordable home-based eye therapies, helping millions of people around the world who are suffering from declining vision.
Lead author Professor Glen Jeffery of the UCL Institute of Ophthalmology said: “As you age, your visual system declines significantly, particularly once over 40.
“Your retinal sensitivity and your color vision are both gradually undermined, and with an aging population, this is an increasingly important issue.”
“To try to stem or reverse this decline, we sought to reboot the retina’s aging cells with short bursts of longwave light.”
For the study, 24 men and women between the ages of 28 and 72 who had no ocular disease or visual decline were analyzed. All participants had eye tests to discover the sensitivity of their rods and cones at the start of the study. Rod sensitivity was measured in dark-adapted eyes, with pupils dilated. This was done by asking participants to detect dim light signals in the dark. Cone function was tested by subjects identifying colored letters that had very low contrast and appeared increasingly blurred, a process called color contrast.
After testing, all participants were sent home with a small LED torch and were asked to look into its deep red 670nm light beam for three minutes a day for two weeks. Participants were then re-tested for rod and cone sensitivity.
Researchers found that the red light had no impact on younger individuals, but for those 40 years old and over, significant improvements were shown. Cone color contrast sensitivity, which is the ability to detect colors, improved by up to 20% in some participants. Improvements were found to be more significant in the blue part of the color spectrum that is more vulnerable in aging. Rod sensitivity, which is the ability to see in low light, also improved significantly, though less than color contrast.
Significantly Improve Vision
Professor Jeffery said: “Our study shows that it is possible to significantly improve vision that has declined in aged individuals using simple brief exposures to light wavelengths that recharge the energy system that has declined in the retina cells, rather like recharging a battery.”
“The technology is simple and very safe, using a deep red light of a specific wavelength, that is absorbed by mitochondria in the retina that supply energy for cellular function.”
The device itself is inexpensive, so researchers hope it can be made accessible to many people who struggle with their eyesight because of retinal aging. This could be an easy, inexpensive way to help slow the decline of vision in many older people.