A miniature telescope implanted into the eye could soon help people with vision loss from end-stage macular degeneration. Last week, an advisory panel for the Food and Drug Administration unanimously recommended that the agency approve the implant. Clinical trials of the device, which is about the size of a pencil eraser, suggest it can improve vision by about three and a half lines on an eye chart.
“This is one of the few options for people with end-stage macular degeneration,” says Kathryn Colby, an eye surgeon at the Massachusetts Eye and Ear Infirmary, in Boston, who helped develop the surgical procedure used to implant the device.
Macular degeneration is the leading cause of blindness in people age 65 and older, affecting more than 10 million Americans. The disease strikes the center of the retina, called the macula, which is especially important for reading, watching television, and recognizing faces. While some treatments exist to slow progression of the disease, no treatments are currently available for those in the latest stages of the disease, who have irreversible damage to the macula. An estimated 50,000 to 70,000 people per year fall into this category.
The implant, developed by VisionCare Ophthalmic Technologies, a start-up based in Saratoga, CA, consists of two lenses within a small glass tube. Once inside the eye, it works like a fixed telephoto lens, acting in conjunction with the cornea to project a magnified image of whatever the wearer is looking at over a large part of the retina. Because only the central parts of the retina are damaged in the disease, magnifying the image on the eye allows the retinal cells outside the macula to detect the object and send that information to the brain. (These cells are normally involved in peripheral vision and normally generate low-resolution visual information compared to the macula cells–you can’t read a sign in your periphery, for example. But magnifying the image also has the advantage of making it easier for the cells to interpret.)
“This change in vision is significant to patients,” says Allen Hill, PCEO of VisionCare. In addition to improving vision, it “provides the ability to have normal eye contact, which is a crucial part of social interaction,” says Eli Peli, a scientist at The Schepens Eye Research Institute, who has consulted for the company.