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Imagine a world where eyeglasses are museum pieces and contact lenses are obsolete. Such a time may not be far off. Government-approved tests of a new operation, in which a laser beam is used to reshape the surface of the eye to correct vision permanently, have been very encouraging, a researcher reported on Wednesday.
So far, 75 patients have undergone the surgery, said Dr. Keith P. Thompson, an assistant professor of Ophthalmology at the Emory University School of Medicine in Atlanta, and a scientist at the Yerkes Regional Primate Research Center.
He said half the patients achieved vision of 20/20 or better, considered perfect. And nine out of 10 improved to 20/40, good enough to pass a driver's test without glasses.
Thompson reported the results of the study to the 10th Annual Science Reporters Conference, sponsored by the American Medical Association.
The U.S. Food and Drug Administration wants to see follow-up reports on 500 patients two years after their surgery before approving the procedure for public use. A new phase of the study, designed to meet that requirement, is now beginning at Emory and various sites across the country, and an FDA ruling may come in three years.
Thompson predicted the surgery might be available to the public by the end of the decade.
Other kinds of operations to correct vision have been developed and used over the last 10 years.
But they involve incisions in the cornea, the transparent membrane that covers the eye. And because the cornea does not heal as well as other tissues, it is left structurally weakened, Thompson said.
By contrast, the new procedure consists of using a new, ultraviolet laser to sculpt the surface of the cornea. The cornea is about as thick as a credit card, and only a few thousandths of an inch are etched away, reshaping the surface to put the eye back in focus.
The operation takes about 15 seconds, and the eye heals within six weeks, Thompson said.
No health risks have been associated with the surgery, he said. Some haze develops in the cornea, but it disappears in three to six months, he said. Some patients see halos when they look at lights, but that, too, seems to resolve itself over time.
Age does not appear to be a factor in the success of the surgery, he said.
Many of the patients in the study, after waiting the six months required by the Food and Drug Administration, have chosen to have their second eye operated on, he added.
So far, the procedure is being used only for nearsightedness. About one of every four people in the United States is nearsighted.
The operation costs $1,500 per eye because the new lasers cost about $400,000 each, and the number of patients is so small, Thompson said. But he said he expected the cost to drop significantly once the operation is available to the public.
Thompson said he did not know whether the operation could be repeated to adjust for continually deteriorating vision. But he said most people's eyesight remains relatively stable, with only slight variations over time.
Some humans received the operation in Europe in the mid-1980s, and the first U.S. patient underwent the operation in 1988.
