A team of researchers from Spain tracked LASIK surgery (laser in-situ keratomileusis) and its forerunner, PRK (photorefractive keratectomy). In both procedures, the cornea is reshaped so that light entering the eye focuses on the retina in the back of the eye, as it does in those with normal vision.
"Our findings are that both are safe after 10 years," and the visual correction holds for the most part, says researcher Jorge Alio, M.D., Ph.D., an ophthalmologist.
The study was presented at the joint annual meeting of the American Academy of Ophthalmology and the Asia Pacific Academy of Ophthalmology.
The 10-Year Study
The study evaluated 200 eyes with nearsightedness (myopia) or with myopia and astigmatism, an irregularly shaped cornea that blurs vision.
One hundred eyes were corrected with LASIK; the other 100 were corrected with PRK. Both procedures use lasers.
On average, patients were 29 when the surgeries were done in 1995 and 1996, Alio says.
The researchers measured each patient's vision 10 years later and evaluated changes on the cornea, which reflect the stability of the procedure.
Most of the vision correction remained, he says. Ten years later, on average, "they read the line [on the eye chart] above what they used to read [immediately after the surgery]."
Put another way, he says, the vision of both groups regressed only slightly.
These patients were highly nearsighted to begin with, he says. After 10 years, the PRK patients' nearsightedness and the LASIK patients' vision regressed only slightly, Alio says.
"This is a very good study," says James J. Salz, M.D., a Los Angeles ophthalmologist and long-time vision correction surgery researcher. The results, he says, show that both eye procedures are "very stable" operations."
While the patients got a bit more nearsighted — and the LASIK patients a bit more than the PRK patients — the results held fairly well, he says.
SOURCES: Jorge Alio, M.D., Ph.D., professor and chairman of ophthalmology, Miguel Hernandez University; medical director, Vissum Corp., Alicante, Spain. James J. Salz, M.D., ophthalmologist, Cedars-Sinai Medical Center, Los Angeles. News conference, Nov. 11, 2006, joint meeting, American Academy of Ophthalmology and Asia Pacific Academy of Ophthalmology, Las Vegas.
By Kathleen Doheny
Reviewed by Brunilda Nazario