Telescope for Macular Degeneration?
FDA Eyes Implantable Miniature Telescope When All Else Fails to Treat Macular Degeneration
How the Implantable Telescope Works
The telescope magnifies images by recruiting other parts of the retina to
make up for the loss of the macula. "What it does is it enlarges the image
that the patients can see to compensate for their macular degeneration, Colby
In the telescope's clinical trial, 206 patients took eye tests before
getting the implantable miniature telescope. One year later, 67% of them could
read at least three extra lines on the doctors' eye chart, compared to their
eye test results before getting the telescope.
"One of the patients I implanted actually was able to return to a
long-loved avocation of sculpting that he had had to give up," Colby
Implanting the telescope is "challenging surgery," says Colby, who
wrote a paper about the procedure in the August 2007 edition of the Archives
Four millimeters may sound small, but for the eye, "it's a large device,
so it needs to be placed in the eye carefully to avoid damaging other
structures within the eye," Colby says.
Those structures include the cornea, which is the eye's outermost layer.
In the telescope's clinical trial, patients had lost 25% of certain corneal
cells one year after surgery. That didn't meet the study's benchmark of losing
no more than 17% of those cells. Cornea specialists met that goal, but not all
of the surgeons who took part in the study were cornea specialists, Colby
The trial's results, published in Ophthalmology in November 2006,
show that most of the corneal cell loss occurred from postsurgery swelling, not
because of ongoing trauma caused by the telescope.
Lloyd notes that after getting the telescope, several patients in the
clinical trial later needed a corneal transplant. That may be in part because
of their advanced age (participants were 76 years old, on average), Lloyd
Tips for Patients
If the FDA approves the implantable miniature telescope, Lloyd and Colby
have some advice for patients.
First, keep your expectations reasonable. For instance, "it's not
realistic to hope that you're going to be able to drive," Colby says.
Second, choose your surgeon carefully. Lloyd suggests asking these
- What are the risks, the benefits, and the alternatives?
- Where did you learn how to do this procedure?
- How many of these operations have you done?
- What is your success rate with this operation?
"It's early going. These things are going to require a lot of care and a
lot of follow-up, and a steep learning curve," Lloyd says.