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Currently the smallest telescope in the world, the implantable miniature telescope (IMT), invented by Dr. Isaac Lipshitz, has roughly the diameter of an apple seed. Here it can be seen balanced on a fingertip. Though not yet FDA approved, the device was helped two out of three patients achieve a three-line or better improvement on eye chart tests in a recent trial. (Visioncare Ophthalmic Technologies Inc.)
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AP -- U.S.
health officials have approved a first-of-its-kind technology to counter a
leading cause of blindness in older adults — a tiny telescope implanted inside
the eye.
The Implantable Miniature Telescope aims to help in the end
stages of incurable age-related macular degeneration, a creeping loss of
central vision that blocks reading, watching TV, eventually even recognizing
faces.
The idea: Surgically insert the Implantable Miniature Telescope
into one eye for better central vision, while leaving the other eye alone to
provide peripheral vision. The brain must fuse two views into a single image,
and the Food and Drug Administration warned Tuesday that patients need
post-surgery rehabilitation to make it work.
There's little to help such advanced patients today aside
from difficult-to-use handheld or glasses-mounted telescopes, while the new
implanted telescope — smaller than a pea — can improve quality of life for the
right candidate, said Dr. Malvina Eydelman, FDA's ophthalmic devices chief.
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A close up of the eye of a patient six weeks after an IMT implantation. The lens of the device can clearly be seen through the patient's pupil. The sutures, which are still visible along the top border of the iris, will eventually be removed. (Visioncare Ophthalmic Technologies Inc.)
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But it's only for a subset of the nearly 2 million Americans
with advanced macular degeneration, Eydelman warned: Those 75 and older, with a
certain degree of vision loss, who also need a cataract removed. In fact, the FDA
took the highly unusual step of requiring that patients and their surgeons sign
a detailed "acceptance of risk agreement" before surgery,
acknowledging potential side effects — including corneal damage and worsened
vision — and the need for lots of testing to determine who's a candidate.
"We're not giving people back 20-year-old eyes,"
cautioned ophthalmic surgeon Dr. Kathryn Colby of Harvard and the Massachusetts
Eye and Ear Infirmary in Boston.
She helped lead manufacturer VisionCare Ophthalmic Technologies' study of the
implant.
But by magnifying images onto more of the retina than its
diseased center, someone who before couldn't see an entire face might now miss
only the nose, Colby said.
click to enlarge
The Implantable Telescope Technology is housed in a prosthetic device composed of three primary components: a fused quartz glass capsule that contains wide-angle micro-optical elements; a clear polymethylmethacrylate (PMMA) carrier; and a blue PMMA light restrictor. The sealed optical component is snap-fitted into the carrier plate. |
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In a 219-patient study, the FDA said 90 percent of telescope
recipients had their vision improve by at least two lines on an eye chart, and
three-quarters went from severe to moderate vision impairment.
Concern about damage to the inside lining of the cornea, the
eye's clear front covering that helps focus light, held up FDA approval for
several years. In that study, 10 eyes had serious corneal swelling, five that
required corneal transplants. FDA's Eydelman said the company proposed candidate
restrictions to minimize that risk, and will study how an additional 770
recipients fare after sales begin.
VisionCare, of Saratoga,
Calif., is seeking Medicare
coverage for the surgery and rehab costs, a package that it calls CentraSight.
The company wouldn't estimate total costs but said the device itself costs
$15,000.
VisionCare Opthalmic Technologies
SOURCE: The Associated Press
