Laser Eye Treatment
Gains Popularity
By DR. ROCK POSITANO
Special to The News
here are an estimated 120 million people in the U.S. who are nearsighted, farsighted or astigmatic. So common are these problems that, during the past five years, new and effective surgical techniques have emerged to address them.
In the past people opted for corrective lenses and contact lenses — nowadays there is a tendency to consider permanent eyesight correction using laser technology.
"Laser vision correction involves reshaping the surface of the cornea, removing microscopic amounts of tissue, thereby allowing images to be more sharply focused on the retina," states Dr. Sandra Belmont, director of the Laser Vision Correction Center at New York-Presbyterian Hospital and associate professor of ophthalmology at the Weill Medical College of Cornell University.
The cornea is responsible for approximately 70% of the total refracting power of the eye. When a person is nearsighted, the cornea is flattened, thereby decreasing the refractive capability of the cornea; in the case of farsightedness, the cornea is given the necessary curvature, increasing the refractive power of the cornea. By altering the orientation of the cornea, surgeons are able to eliminate or lessen the need for corrective lenses.
The laser procedure termed LASIK was approved by the FDA in 1995. Approximately 1 million procedures of this type were performed in the U.S. during 1999.
"Laser vision correction is a onetime procedure, and the treatment itself is painless," according to Belmont. She adds that "a recent study demonstrated that 98% of patients treated for nearsightedness with this procedure were able to pass a driver's test without corrective lenses." Most patients can return to work the next day, although two or three days is recommended.
A prospective patient who can benefit from this procedure must meet certain eligibility criteria. For example, the patient must have healthy eyes and have stable vision for at least one year before the procedure. Patients with degenerative or autoimmune diseases, diabetes or are pregnant or nursing are not good candidates. The patient must be at least 18 years old to treat nearsightedness and 21 years old to treat astigmatism.
Before getting this treatment, the patient undergoes an extensive eye examination by a board-certified ophthalmologist. Corneal topography, a test that provides the clinician a computerized map of the eye and allows for the inspection of the shape of the cornea, is performed. High-frequency ultrasound is used as a diagnostic tool to produce an image of the eye to rule out disease.
What treatment options are on the horizon for people who suffer from farsightedness? There is a new laser procedure for the treatment of farsightedness that is undergoing FDA evaluation. It is called the Sunrise LTK procedure. Unlike the LASIK procedure, LTK does not remove tissue from the cornea, but instead causes shrinking of the tissue. This gives the cornea more curvature. Many surgeons contend that this new laser technique will become the procedure of choice for correction of farsightedness in the near future.
For further information on laser vision correction, check out the following Web site: www.nycornell.org/vision.
Original Publication Date: 11/28/1999 |
