Bionic eyes? Implanted telescope offers hope for those with macular degeneration
University of Michigan Health System
U-M's Kellogg Eye Center is taking part in national study to test safety, effectiveness of new procedure
At age 60, Briana Daudert was an independent and active grandmother – spending her time working, reading, cooking and keeping up with her 10 grandchildren. But in less than a year, she lost vision in both eyes due to macular degeneration, a common eye condition that affects more than 13 million Americans – usually those over age 60.
"I thought that I had a cataract in my right eye, so I was surprised by the news that it was macular degeneration," says Daudert. "When I lost vision in my left eye, I was no longer able to drive -- that took away my independence, which was very depressing because I didn't feel old. It also affected my ability to read recipes and cook, something I very much enjoy," she says.
While there is no cure for macular degeneration, the University of Michigan Kellogg Eye Center is studying a new procedure that may bring improved sight – and quality of life – to patients suffering from this debilitating eye condition.
"We are taking part in a national collaborative clinical trial that involves implanting miniaturized telescopes into the eyes of 220 already-identified study participants," says Paul Lichter, M.D., director of the U-M Kellogg Eye Center. "These patients were selected because they had a certain level of vision and a certain ability to adapt to this telescope."
Age-related macular degeneration is a problem in the retina – the light-sensitive tissue at the back of the eye that changes light into impulses interpreted by the brain as images. The center of the retina is called the macula.
"Over time, scarring of the macula can make it difficult to see fine detail in the center of the visual field, leading to problems with reading, driving or seeing features on a face," explains Lichter. "This can be quite a devastating problem to people who suffer from moderately severe to severe macular degeneration."
The implantable telescope is a small device that is placed into the patient's eye with the poorest vision during a one-hour outpatient surgical procedure. It is not a complete telescope but rather a set of lenses encased in a plastic-like covering that allows the cornea of the eye to serve as the forward lens of the telescope. It takes the image from an object, magnifies it two to three times its normal size and projects it beyond the scarred macula so that parts of it can be seen by the individual and then recognized after intensive training.
"Once the telescope is in, the eyes can't work together anymore because the brain can't fuse the larger image formed through the telescope and the smaller image formed by the other eye," explains Cheryl Terpening Frueh, O.T.R., an occupational therapist at the U-M Kellogg Eye Center.
"The smaller image is more predominant so we have to teach patients to recognize the larger image and suppress the smaller one. Because they still have macular degeneration, there are going to be some blurry spots. But as vision improves and the eye heals, we can work on smaller and smaller images," says Frueh.
Because the implantable miniaturized telescope is an optical improvement and not a cure, Lichter stresses to his patients that this is not a 'wow' procedure.
"Patients won't have this done, take off their bandage and say 'My goodness, my vision is restored.' It takes patience and lots of forbearance upon the patient's part and the therapist's part," he says.
As Lichter puts it, "Patients who have this procedure still won't be able to see all of your face, but they can learn to interpret your face by perhaps moving their eye a bit, so they get different parts of your face projected on the retina at different moments. They can then put it all together to recognize a face, words on a page or pictures on a screen."
"I wanted to take part in the trial at U-M because I felt it was the only hope I had of being able to see better, and it truly has improved the quality of my life," says Daudert, now 64. "But it does take concentration. I still close the left eye if I want to use the telescope and close the right eye if I want to see distance.
"Now I'm able to read in good lighting -- print as small as newspaper and definitely my recipes," continues Daudert. "I'm especially happy to be able to read to my grandchildren and watch them grow up."
Like Daudert, Lichter says most patients are very pleased with the telescope.
"In earlier studies in Europe, patients had improvement of two to three lines of vision on the eye chart with the use of the telescope," says Lichter. "And we have found the same thing here in our patients.
"Although the clinical trial is now closed to new patients," he adds, "we hope that the Food and Drug Administration will approve the telescope for wider use once this set of 220 patients has been monitored for a two-year period to ensure the health of their eyes and the long-term effectiveness of the telescope."
Symptoms of Age-related Macular Degeneration (AMD):
Types of AMD and Standard Treatments:
Causes of AMD:
The Implantable Miniature Telescope study is being funded by VisionCare Ophthalmic Technologies, Inc.
For more information, or to contact University of Michigan Health System, see their website at: www.med.umich.edu
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