Eye Braces?

Changing the cornea's curve

Back in the early 1960s, two Southern California optometrists named Stuart Grant and Charles May learned of a surprising effect in patients they had fitted with contact lenses. The patients had been given the lenses to correct myopia, or nearsightedness, a condition that usually gets worse rather than better. Yet some of these people, after wearing contacts for only a few months, found their vision without lenses had mysteriously improved. Recalls Grant: "Sometimes they would get halfway to work and realize that they were not even wearing their contacts."

Out of that chance discovery 17 years ago has emerged a new and highly controversial treatment for helping flawed vision. It is called "orthokeratology." In myopia, images of the outside world do not focus precisely on the retina but rather in front of it, either because the eyeball is too long or because the cornea and lens bend light rays too much. Just as orthodontists use braces to correct the position of crooked teeth, orthokeratologists employ hard contact lenses to alter the curvature of the cornea to improve vision. At least 300 optometrists now specialize in "ortho-k," and tens of thousands of Americans are believed to have undergone the increasingly popular treatment.

Yet even ortho-k's supporters acknowledge that there is little hard scientific evidence to support some of the claims made for it. The best results seem to be in correcting young myopics. Patients are usually treated with a standard contact lens worn for up to 16 hours a day. Either through pressure or undetermined factors--the cause is still disputed --the cornea does seem to flatten out. After about six weeks the cornea's new curvature is measured, and new contact lenses prescribed, usually with a flatter curve. During the therapy, which can last two years and cost $1,500 and up, the patient may be obliged to wear more than half a dozen pairs of lenses. When the optimal curvature and vision are reached, the patient is assigned the final minimum prescription lenses, which are worn at night or perhaps only a few hours or so a day to ensure that the proper curve is maintained.

Orthokeratologists say that they have been able to improve vision so dramatically that many people once with visual acuity of 20/200 or worse are now able to walk around without glasses or contacts for the better part of the day. Says Gale Dixon, 32, a part-time actress and singer who once had 20/800 vision: "When I first started, the world was totally out of focus. Now I get up in the morning and can see fairly well. It gives me a lot of freedom." Critics do not deny that limited improvements may indeed occur, but they point out that they are at best temporary, and that the cornea will eventually spring back to its old shape. They also worry that the treatment, especially in the hands of less skilled practitioners, can cause permanent astigmatism and other eye damage. Says Ophthalmologist G. Peter Halberg, a specialist in contact lenses at St. Vincent's Hospital in Manhattan: "Properly presented and investigated, orthokeratology could be acceptable some time in the future. There's a lot of chaff and some grain, and we are in the process of separating the grain from the chaff."

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