A new telescopic contact lens may help patients with age-related macular degeneration (AMD), according to researchers from École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland.
Photo courtesy of EPFLSan Jose, CA-A new telescopic contact lens may help patients with age-related macular degeneration (AMD), according to researchers from Ãcole Polytechnique FÃ©dÃ©rale de Lausanne (EPFL) in Switzerland.
The device incorporates a thin, reflective telescope inside of a 1.55 mm-thick scleral contact lens. Small mirrors within the device bounce light around to expand the perceived size of objects and magnify the view, similar to that of low-magnification binoculars.
Researchers spent several years making the lens more breathable. The lens is made from several precision-cut, carefully assembled pieces of plastics, aluminum mirrors, and polarizing thin films, along with biologically safe glues. In order to allow oxygen to flow around and underneath the lens, researchers incorporated air channels 0.1 mm wide within the lens.
“We think these lenses hold a lot of promise for low vision and age-related macular degeneration (AMD),” says Eric Tremblay, PhD, an EPFL researcher. “It’s very important and hard to strike a balance between function and the social costs of wearing any kind of bulky visual device.
There is a strong need for something more integrated, and a contact lens is an attractive direction. At this point this is still research, but we are hopeful it will eventually become a real option for people with AMD.”
In order to control the magnification, researchers developed glasses to be worn at the same time as the lens that can detect a wink-while ignoring blinks-that will switch from normal vision to magnification. Users will wink the right eye magnification and the left eye for normal vision.
According to EPFL, the glasses electronically select a polarization of light to reach the contact lens. The lens allows one type of polarization in the 1x aperture and another in the 2.8x aperture. The user sees the view in which the polarization of the glasses and the contact lens aperture match.
The glasses are already on the market for AMD patients who use a mounted telescope, but researchers say such a device tends to look too bulky and does not track eye movement.
Researchers say the ability to control the magnification was necessary for the lenses to be useful for people who are not suffering from AMD.
EPFL researchers partnered with Joseph Ford, PhD, an electrical and computer engineering professor at the University of California, San Diego, along with Paragon Vision Sciences, Innovega, Pacific Sciences and Engineering, and Rockwell Collins.
“This is an intriguing and ingenious optical mechanism,” says Optometry Times Editorial Advisory Board member Leo Semes, OD, FAAO. “The advantage would be for those eligible for bioptic telescopes to avoid the cumbersome-and for some cosmetic-hurdle of obtaining improved vision.
“Clearly, the 2.8X magnification that these researchers have optimized strikes a good balance between enhanced visibility and magnification,” he says, speaking exclusively with Optometry Times.
Optometry Times Editorial Advisory Board member Sherry Bass, OD, FAAO says the device could be an option for patients with AMD because it offers significant magnification and a better field of vision than standard telescopes.
“In addition, it is a scleral lens, and therefore larger and sturdier than typical contact lenses. The patient with AMD and reduced dexterity may be able to handle this type of lens better than a soft, pliable contact lens,” says Dr. Bass.