Farsighted surgery reaches trial stage.

Laser surgery to repair nearsightedness has become common over the past 8 years. In nearsighted people, the cornea of the eye refracts light too strongly and makes nearby objects more clearly visible than distant ones. To fix the problem, surgeons use lasers--precise enough to cut a human hair lengthwise--to shave off the protruding central portion of the cornea, flattening the front of the eyeball slightly and correcting the excessive refraction.

Repairing farsightedness has proved more difficult. The surgeon must shave away portions of the cornea around the front of the eyeball, while leaving the center intact. This procedure makes the refracting surface more conical. Creating troughs indeed improves eyesight, but these areas tend to fill in with scar tissue.

"The body doesn't like a ditch," says Edward E. Manche, an ophthalmologist and director of refractive surgery at Stanford University School of Medicine. In initial trials on animals, scar tissue formed after only 3 months, rendering the procedure useless.

Manche is now employing a new one. "We circumvent, to some degree, the body's healing process," he says. Again using the laser, Manche shaves away a more gradual slope. The result is a shallower trough around the eyeball that allows for some regrowth of the cornea.

After receiving approval from the Food and Drug Administration this spring, Manche and other doctors at Stanford began testing the new technique with 30 farsighted patients. The entire procedure takes less than half an hour, with laser time occupying under a minute.

The Stanford trial is self-supporting. Patients pay $1,900 per treated eye, Manche says. The procedure is likely to remain in trials for 1 or 2 years before getting full approval, he predicts. About 20 percent of the U.S. population is farsighted.