Lens Implant May Help Correct Cataracts

Sep 17, 1:24 PM EDT
Lens Implant May Help Correct Cataracts
By BRUCE SMITH
Associated Press Writer

CHARLESTON, S.C. (AP) -- Ophthalmologists have revolutionized cataract surgery by implementing a new, cutting-edge multifocal lens implant.

A patient who underwent the procedure reported that she's seeing better for both distance and reading. She also has no more use for glasses, something usually required by replacing the cataract with single focal-length lens.

Cataracts are the clouding of the clear lenses in the eyes. The lens becomes brittle, and yellowish. Although some cataracts are congenital and occur in young children, most of us will get them with age.

"If we live long enough, everyone will get a cataract," said Dr. M. Edward Wilson Jr., chairman of the Department of Ophthalmology at the Medical University of South Carolina's Storm Eye Institute.

Kate Reiss, 55, a Charleston resident who teaches school in nearby Summerville, recently underwent cataract surgery in which she received the new implant.

"It's phenomenal. It's just unbelievable," said Reiss, who had a lens implanted in her second eye a few weeks after the first.

"For the first couple of days, when I would read the newspaper in the morning, I had my glasses right there," she said. But she never uses them. "I haven't had the nerve to throw them away yet. But I don't use them for anything."

"This is the first implant I have come across where we have a real wow effect," said Dr. Kerry Solomon, the director of the Magill Laser Center at the institute.

"They are reading labels on medicine bottle. They are reading phone books. They are reading stock tables without glasses as well as driving their cars and watching TV," he said.

The Storm Eye Institute is one of a handful of centers across the nation conducting clinical tests on the new generation lenses, which could be approved for general use by late next year, Solomon said.

"We have put in 60 to 70 of these implants now and no one uses glasses for anything," Solomon said.

"The technology for these devices has advanced so much," said Dr. Janine Smith, the deputy clinical director at the National Eye Institute in Bethesda, Md. "In 25 years from now, when there are roughly twice as many people over 65, there will be many more new options than in the past."

Surgical techniques have improved so much that, in many cases, the procedure is done as outpatient surgery.

"It's not like it's a trip to the mall, but it is outpatient," Smith added. With increasing frequency, some middle-aged patients are opting for a procedure called clear lens extraction. "It's the same thing as cataract surgery except the lens is not cloudy and insurance does not pay for it," Solomon said.

A multifocal lens would mean the patient would no longer have to use glasses and could avoid the need for cataract surgery when cataracts eventually do develop.

But for younger patients, those in their 20s and 30s, such a procedure doesn't really make sense, even if one day they develop cataracts.

"There is some risk associated with surgery," said Smith, who adds you wouldn't want to do such surgery unless it was necessary. And, she said, while the technology is good and getting better, the body's natural lens is still better at focusing on its own.

Aging also can bring problems with the eye's cornea, the transparent tissue on the front of the eye. It's a different problem but one also being addressed at the Storm Eye Institute.

"The cornea is hazing so you can't see through it - light scatters and you can't see images well," said Dr. David Vroman, a faculty member in MUSC's Department of Ophthalmology. "The patient won't know if it's a cataract or a cornea. They'll just know that they have blurry vision."

Doctors know how to replace the cornea by transplanting a donor cornea.

"What we're working on is just replacing the portions that are abnormal," Vroman says. "If you have a problem with the back portion of the cornea, we're working on removing just that back portion like a layer, like a sheet."

"The idea is to keep the eye as stable as possible. You can imagine if we made a big cut through the cornea, the whole eye is weakened," Vroman adds.

"Technically, it's much more difficult," Wilson says. "But if you can think of taking a layer of the eye out and replacing a layer, the rejection rate goes down. One of the layers that leads the pack in rejection is not a layer that needs to be replaced much of the time."

Vroman said some scientists are working to develop artificial corneas.

"But the long-term survivability of an artificial cornea is not great," he adds. "The eye just doesn't like that kind of foreign material. We can't integrate that kind of foreign material on the surface of the eye very well."