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Associated Press
FDA Panel Recommends Against 'Bionic Eye'
By ANDREW BRIDGES , 07.14.2006, 06:38 PM
In the 1970s TV show "The Six Million Dollar Man," the strapping young astronaut got a bionic eye. A U.S. company had hoped that next year that might be your grandmother. Not so fast, a federal advisory panel said Friday.
A tiny telescope designed to be implanted in the eyes of some elderly patients should not receive Food and Drug Administration approval, the panel recommended on a 10-3 vote.
The FDA's ophthalmic devices panel recommended against the pea-sized bionic device for safety reasons, spokeswoman Heidi Valetkevitch said.
The first-of-its-kind device is called the Implantable Miniature Telescope. The telephoto lens could enable some patients to do away with the special glasses and handheld telescopes they now use to compensate for the loss in central vision caused by age-related macular degeneration, according to VisionCare Ophthalmic Technologies Inc., its manufacturer.
Allen Hill, the chairman and chief executive of the Saratoga, Calif., company, did not immediately return a message seeking comment.
The FDA typically follows the recommendations of its outside panels of experts, but isn't required to do so.
The miniature telescope contains two lenses that work with the cornea to create a magnified image that is projected onto a wider area of the retina, improving central vision, according to the company.
The device is designed to be implanted only in one eye, which would provide central vision. The other eye, left untouched, would be responsible for peripheral vision, leaving the brain to combine the two views to form a single image. Getting used to that could require patients to undergo professional rehabilitation, the FDA said.
The surgery to implant the telescope is more difficult than conventional cataract surgery and can lead to damage to the inside of the cornea, according to the company. Patients also may experience a higher rate of loss of cells lining the cornea, which can require removal of the device and a cornea transplant.
In clinical trials, 141 of 193 patients implanted with the device showed after a year improved distance and near visual acuity, defined as the sharpness of vision in reading an eye chart, according to FDA documents. Ten patients reported a loss in acuity in either distance or near vision. Doctors removed eight of the devices, four of them from patients dissatisfied with how they worked, FDA documents show.
Macular degeneration typically affects the elderly. The disorder leads to a weakening or breakdown of the cells in the macula, or the bull's-eye of the retina crucial for the straight-ahead vision needed to read, watch television and recognize faces. Patients with macular degeneration suffer from blind spots and distorted vision.
Ophthalmologists initially worried about the weight of the device, which even at 1/250th of an ounce weighs more than traditional implanted lenses, but experiments didn't suggest that was a problem, said Dr. Lee Duffner, a Hollywood, Fla., ophthalmologist and American Academy of Ophthalmology spokesman.
"Many people with age-related macular degeneration have great difficulty using handheld magnifying devices," Duffner said. "Concurrent with the aging process that affects the eye, one loses one's strength, coordination and steadiness. By implanting the lens in the eye, it's directly placed in the optical system of the eye and is much easier for patients to use," Duffner said.
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07-18-2006 10:17 PM
