Doctors discovered more than 100 years ago that placing a hot needle in the cornea of the eye would cause it to change shape, becoming steeper.
But that clue to improving the near vision of farsighted people was never put to much use--until now. New techniques--one recently approved by the Food and Drug Administration and another expected to be available to consumers next year--could make vision correction surgery a popular option for farsighted people.
In farsightedness, or hyperopia, the eye's corneas are too flat. In childhood and early adulthood, the eye is usually still able to focus despite the defect. But, as the person ages, the focusing range decreases. This usually leads to blurred near vision after age 40 and, eventually, poor distance vision too. (This is different from presbyopia, which involves the decline of near vision only after age 40 or so.)
Unlike those with nearsightedness, or myopia, who have been flocking to laser vision centers (mostly for the Lasik procedure, in which the cornea is cut to altervision) over the past three years, there have been few satisfactory surgical options for farsightedness.
Lasik and other surgeries that involve cutting the cornea can be used for farsightedness to some degree, but they were created primarily for nearsightedness and carry some risks.
"Hyperops have been neglected," says Dr. Sandra Belmont, director of the Laser Vision Correction Center at Weill Cornell Medical Center in New York City. "There was a big rush to treat myopia all these years. But there are more potential candidates for [a hyperopia] procedure than for myopic Lasik. Now we can say to hyperops that there is a specific technique designed for you."
That technique is the Sunrise Hyperion Laser Thermal Keratoplasty, which was approved by the FDA last month for correcting mild to moderate farsightedness in people who don't have astigmatism (another type of vision distortion in which the curve of the cornea is unequal).
Another technology to correct farsightedness--conductive keratoplasty, which uses radio waves to heat the cornea--is in stage-three clinical trials and could become available to consumers as soon as next year.
Although there are some drawbacks to the new FDA-approved LTK procedure, it could help make surgery the preferred method for treating imperfect vision, experts suggest.
