Bifocal contact lenses are now a solution for some people with sight problems. (Star-Telegram/Kelley Chinn)

Innovations bring focus to those aging eyes

By Terry Lee Goodrich
Star-Telegram Staff Writer

As people get older, things often get harder.

The arteries. Remembering the last name of the person they met last week. And the lenses of the eyes - the part that allows them to focus.

That loss of elasticity - presbyopia - is why some may find that the only way to see fine print is to hold a page at arm's length - until, as some quip, the arms are no longer long enough.

But researchers have come a long way in recent years with special contact lenses to correct the problem. And surgery may offer future solutions, researchers say.

"After age 40, vision is about compromise," Bedford optometrist Jerry Latham said. "A lot of it is trial and error, based on a person's occupation, personality, eyes.

"A patient has to be motivated. And there has to be patience on the doctor's part and on the part of the patient."

Monovision contacts is an option. One lens is fitted to allow one eye to see close, the other to allow the other eye to view distant objects. Unlikely as it sounds, the brain can adjust to that, Latham said.

"About 80 percent of the people who try those are satisfied," he said.

A more recent innovation is bifocal contacts, with concentric circles having different focuses. They focus light on the retina, which sends the message to the brain.

With them, "what the eye gets is simultaneous distance and near focus combined on the retina, the back of the eye," said Adrian Glasser, an assistant professor at the University of Houston College of Optometry.

"Some parts of the world are in focus. Some are not. The brain and retina together can sort of selectively choose. It's a complex optical principle," Glasser said.

The advent of disposable lenses several years ago makes it easy for optometrists to try several lenses on a patient before they leave the optometrist's office, said Joseph T. Barr, professor with Ohio State University College of Optometry. He writes Editor's Perspective for the Contact Lens Spectrum.

"The bad news is that they aren't for everybody. The vision isn't always the best, and they cost more," he said.

Kathy Huber, 49, of North Richland Hills, who said she is "horribly far-sighted," has tried glasses, hard contacts and monovision contacts. She found that her eyes are better able to adjust to bifocal contacts than monovision.

"It's a matter of hating glasses that bad," she said. "I see pretty much all the way around, and he [Latham] says that close up could be as good as I wanted if I gave up some distance. But I wanted distance to drive, because I have two kids. And I keep the reading glasses with me just in case."

Surgical alternatives are being tested on animals and occasionally on people.

One can be combined with cataract surgery to replace a cloudy lens. Because an artificial lens will be inserted anyway, some surgeons give patients on option of trying monovision or bifocal artificial lenses.

"The surgeon can say, 'We're testing new lens that may enable you to see clearly both at a distance and near. But if it doesn't, you'll be no worse off than you were,' " Glasser said.

But surgery only for presbyopia is "a little scary, because there's always risks for infection or failure - and you might end up worse off," he said. "Unlike with a regular contact lens, if you don't like them, you can't take them out and throw them away."

But many ophthalmologists - among them Lyle Freedman of Fort Worth - would not implant monovision or bifocal artificial lenses, feeling the technique is not advanced enough.

"Most people are just happy if they can see at a distance with no glasses or thin glasses - and they don't mind wearing glasses for close up," he said.

Researchers also are exploring injecting a liquid plastic that would soften the lens, then harden back into the shape of a normal lens, Glasser said.

"It might be that eventually, we'll be able have a lens that is tailor-made for a person," he said. "In the future, we may be able to develop some that behave in the same way a young person's do."

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