Sept. 9, 2003 — Imagine having the eyes you had when you were 20. An experimental new material promises to do just that and may one day eliminate the need for bifocals by helping old eyes feel and see like new again.
Researchers say the gel-like material may eventually be used to replace old, aging lenses in the eye; offering a new way to treat cataracts as well as presbyopia or “old vision.” Nearly everyone over 40 suffers from some form of presbyopia, which makes it more difficult to read without magnification.
“This could represent a totally different approach to the treatment of cataracts and presbyopia,” says researcher Nathan Ravi, MD, PhD, associate professor of ophthalmology and visual sciences at Washington University in St. Louis, in a news release. “As we age, the lens of the eye gradually loses its ability to adjust its focus.
“We have demonstrated that this gel has similar mechanical properties to the lens of the eye, and we hope it also will be able to perform the visual functions of the natural lens,” says Ravi.
Gel May Revive Aging Eyes
The polymer gel-like material is a modified hydrogel similar to those used in many extended-wear contact lenses.
“The gel material is soft to the touch, and it has elastic properties similar to those found in the natural human lens,” says researcher Madalene Fetsch, a graduate assistant at Washington University, in a news release. “It also looks as if it has the potential to be injectable, which would mean it could be delivered with less invasive surgery.”
By making the gel injectable, researchers say they would also avoid the current practice of cutting a slit in the eye in order to insert a replacement lens during cataract surgery.
Researchers say the new strategy would call for removing the old and clouded lens material from the capsular bag that holds the lens in the eye while leaving the rest of the structure intact. Then the surgeon would replace the old lens material with the clear, flexible polymer gel by injecting it into the empty capsular bag.
Researchers presented the findings this week at the American Chemical Society National Meeting in Washington, D.C.
More Research Needed
So far, they say the main problem with the gel is that they have to improve the gel’s refractive index. This is the degree to which the gel refracts light and allows the eye to focus. But researchers say other scientists have been successful in improving the refractive index in similar gels.
Researchers say they hope to begin animal testing of the gel early next year.
“Assuming that we make it all the way to human studies, we would probably first offer it to cataract patients because by that time they almost certainly would have presbyopia and they’re looking at a similar surgery anyway,” says Fetsch.
After that, she says the treatment would be offered to people with presbyopia who no longer want to wear bifocals or contacts.