LASIK eye surgery an Alternative to Corrective Lenses
LASIK eye surgery — short for laser-assisted in-situ keratomileusis — has resulted in making clear vision a reality for millions of people who used to rely on glasses or contact lenses. With increasing experience and advances in technology, outcomes and predictability of LASIK eye surgery have greatly improved in recent years.
LASIK eye surgery changes the shape of your cornea — the transparent membrane that arcs over your pupil and the colored part of your eye (iris). After the procedure, your cornea should bend (refract) light rays to focus more precisely on your retina rather than at some point beyond or short of your retina.
LASIK eye surgery may be an option for you if you have nearsightedness (myopia), farsightedness (hyperopia) or astigmatism. Nearsightedness occurs when the eyeball is slightly longer than normal or when the cornea curves too sharply, causing light rays to focus in front of the retina and blurring distant vision. Farsightedness is the opposite, in a way: A shorter-than-average eyeball or too-flat cornea focuses light behind the retina instead of on it, making near vision and sometimes distant vision blurry. When the cornea curves or flattens unevenly, the result is astigmatism, which disrupts focus of near and distant vision.
Your eye doctor will likely recommend that you try other ways of correcting your vision before you turn to LASIK eye surgery or another similar procedure. Glasses or contact lenses are your first option. Unlike sight-threatening eye diseases, refractive errors aren’t progressive in themselves, and they may actually improve in middle age. Some doctors are reluctant to endorse LASIK eye surgery, reasoning your eyes are basically healthy even if you have nearsightedness or farsightedness. A good surgical outcome depends on careful evaluation of your eye before the surgery.
Other types of refractive surgery
Your eye doctor may recommend another type of refractive surgery if you’re not a good candidate for LASIK eye surgery. These include:
- Photorefractive keratectomy (PRK). PRK is sometimes used if you have a low to moderate degree of nearsightedness or farsightedness, or if you have nearsightedness with astigmatism. PRK removes the thin surface layer of your cornea (epithelium). Your eye surgeon then uses a laser to flatten your cornea or make its curve steeper.
The exposed surface of your cornea repairs itself, assisted by a contact lens you wear as a bandage over your eye for three or four days after surgery. You might have eye pain for a few days until your cornea heals. It generally takes up to a week for your eye to regenerate the surface tissue that was removed. During this time you’ll notice variations in your vision. It may take three to six months before your vision improves completely. Most people undergoing PRK have both eyes done on the same day.
PRK has become less common in recent years because more eye surgeons prefer the LASIK procedure. Healing after LASIK is more predictable and usually involves less discomfort and scarring.
- Laser epithelial keratomileusis (LASEK). LASEK is similar to LASIK eye surgery and might be an option if you aren’t eligible for LASIK. During a LASEK procedure, a much thinner layer — the surface layer (epithelium) — of your cornea is folded back to allow the laser to focus on parts of your cornea that need reshaping. The epithelial flap is then replaced.
If you have very thin corneas, you might be a better candidate for LASEK because the procedure allows your doctor to remove less of your cornea. People who play sports or have jobs that carry a high risk of eye injuries might also prefer LASEK because a thinner flap means less damage to your vision should the flap be torn before it can heal. As with LASIK, the LASEK procedure can be done on both eyes on the same day.
