NPR.org, October 19, 2006 · We asked for your questions last week after features on the vision-correcting surgical procedures Lasik and radial keratotomy.
Here, Dr. Rex Hamilton, assistant professor of ophthalmology at the University of California, Los Angeles, and Dr. James Salz, clinical professor of ophthalmology at the University of Southern California, discuss Lasik's success rate, side effects, and the need to tailor expectations to the condition of your eye:
NPR: A number of people wrote in saying they had Lasik within the last three to seven years and were troubled by how much their vision has regressed. Some say they're back in glasses or contacts, while others say they're back to their original prescriptions. How typical is such vision regression?
If people say their vision has gotten worse, most of the time they're talking about their reading vision, primarily because they're getting older. Deterioration in reading vision happens to everyone around age 40 to 45. If what they really mean is that they have become more nearsighted again, that's pretty rare; that's maybe 5 percent of Lasik patients. That 5 percent refers to a significant change, about a -1 diopter or more, over a 10-year period. Many of these patients can successfully undergo an enhancement procedure to get rid of that residual nearsightedness.
I should point out that with the technology used in Lasik more than five years ago, there was a higher incidence of regression because of the way the cornea was reshaped.
It's highly unusual for someone's vision to revert to the original prescription. I've never seen that, and if that did occur, it could indicate that other things are going on with the eye, such as a cataract. Distance vision should not drift appreciably once you've gotten to your original target vision with Lasik.
The most common risk factor for regression is dry eyes. If you have dry eyes and it goes untreated, you can experience some regression, or loss of effect from the surgery.
