California Institute of Technology student Colin Cook and a group of Caltech researchers have developed a glow-in-the-dark contact lens they say may help prevent vision loss in individuals with diabetic retinopathy.
The lenses aim to reduce the metabolic demands of the retina, namely the retina’s night-time oxygen demand. To do so, the lens gives the rod cells the faintest amount of light to look at while the wearer sleeps. “If we turn metabolism in the retina down, we should be able to prevent some of the damage that occurs,” Cook said.
The illumination is provided by tiny vials filled with tritium, a radioactive form of hydrogen gas that emits electrons, which are then converted into light by a phosphorescent coating. This system ensures a constant light output for the lifetime of the contact lens.
The vials are implanted in the lens in a radial pattern, creating a circle that is just big enough to fall outside of the wearer’s view when the pupils are constricted in lighted conditions. In the dark, the pupil expands, and the faint glow from the vials can illuminate the retina. The contact lens design also ensures that the retina receives an appropriate dose of light throughout the night.
Early testing shows that rod cell activity is reduced by as much as 90% when worn in the dark. In the next few months, Cook and his fellow researchers plan to start testing the lenses to see if their ability to reduce retinal metabolism will translate into the prevention of diabetic retinopathy. Following those tests, they will seek FDA permits to begin clinical trials.