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Nobody has ever gone broke overestimating human vanity or laziness--so it's not surprising that late-20th-century technology is about to offer us yet another way to see without glasses. For those who find it too much of a drag to fuss with contact lenses--and who don't mind forking over $2,000 to treat just one eye (with no insurance reimbursement)--perfect vision without any corrective lenses may be just over the horizon. But don't throw away your saline solution yet; this new form of surgery is not for everyone--and it must still win approval from the U.S. Food and Drug Administration.
The experimental procedure, called photo-refractive keratectomy (PRK) and performed only by ophthalmologists, uses a new "excimer" laser to treat moderate degrees of nearsightedness (myopia). Glasses and contact lenses correct myopia by bending or refracting the light entering the eye so that it strikes the retina precisely. PRK does the same thing by changing the shape of the cornea (the eye's clear protective covering).
Controlled by computer, the excimer laser used in PRK emits short, high-energy pulses of cool ultraviolet radiation. Unlike lasers used in other types of eye surgery, which destroy tissue with heat, the excimer vaporizes microscopically thin sections of the cornea by breaking the chemical bonds between molecules-- without harming adjacent tissue. The treatment, which can theoretically be modified to treat farsightedness and astigmatism as well, is currently being tested on 1,400 volunteers at 20 U.S. medical centers. The nearsighted subjects pay for the procedure themselves.
PRK, performed in the physician's office with local anesthesia, is a far more sophisticated procedure than a controversial form of surgery called radial keratotomy (RK). First attempted in Japan and refined in the Soviet Union during the 1970s, RK also corrects myopia by flattening the cornea. Instead of utilizing a laser, RK employs a scalpel to make a sunburst pattern of incisions in the cornea. The operation can weaken the structure of the eye and may result in unstable vision. In one study reported last year, 25 percent of RK patients had worsening eyesight after four years.
Physicians working with the "cool" laser say it has more promise than the older procedure. "The early evidence suggests that [the results] will be more predictable," says Dr. Marguerite McDonald, who has treated 81 myopic patients at Louisiana State University. Most PRK patients are pleased with the immediate outcome of their surgery. They wear an eye patch for a few days and can notice improved vision right away. The other eye can be treated six months later. Bennett Carriere, 51, a New Orleans writer, had 20/100 vision before his surgery in 1989. "Everything around me was like looking at a Monet painting," he says. "I had my own impressionist world." Today Carriere's world is representational; his vision is better than 20/20.
The new procedure is not practical when nearsightedness is still progressing--and it doesn't work for extreme myopia yet. The suspected reason: removing a larger amount of corneal tissue may trigger a more aggressive "healing" response, in which the cornea grows back with scar tissue. "The trick is whether or not we fool the body into thinking nothing has happened," says Dr. Jerald Tennant of the Dallas Eye Institute. Like other physicians working with the excimer laser, Tennant is pleased about his initial results; 90 percent of his patients can now drive without glasses.
Most ophthalmologists, however--including those testing the new laser--agree that before the procedure is done, patient and doctor must weigh the risks and benefits. Nobody has gone blind from PRK, but it does have potential drawbacks, including a recurrence of myopia, swelling and tissue damage. Dr. Roger Steinert, a Boston cornea specialist who is testing the laser, accepts only patients who can't use glasses or contact lenses, like firefighters or police officers who aren't allowed to wear them on the job.
Despite all the unknowns, patients who have had the laser treatment don't seem to care that the verdict is not yet in on it. "I can actually see the golf ball. I can actually see the tennis ball," exults Bob Lobel, 47, a sportscaster for Boston's WBZ-TV who had his cornea reshaped in February. For many others like Lobel, apparently, life without lenses is worth the risk.