LASIK (laser-assisted in-situ keratomileusis) is a relatively new type of laser surgery for correcting nearsightedness (myopia) and astigmatism. Sometimes called "flap and zap," LASIK makes a small flap in the cornea and removes some of the tissue exposed by the flap. The laser removes tissue from the cornea very accurately without damaging nearby tissues.
This procedure may not be available in all areas, but it is done in most large cities.
LASIK is performed in a surgeon's office or same-day surgery center and does not require a hospital stay. It takes about 10 to 15 minutes per eye.
LASIK usually requires very little recovery time. Most people who have the surgery see quite well the next day. In contrast to photorefractive keratectomy (PRK), there is little or no pain after the surgery.
Your doctor will want you to come in for an exam a day or two after the surgery and for regular follow-up exams for about 6 months.
After LASIK surgery to correct nearsightedness, home care may be needed.
- You will feel irritation and scratchiness in the eye the day of surgery. Your eyes may water a lot.
- You may need to wear an eye shield for a few days after surgery.
- Your vision will probably be hazy or blurry for a few days or a week after surgery. Do not drive until your vision has cleared.
- Your doctor may prescribe eyedrops to reduce inflammation and the risk of infection. You may need to use them for several months after surgery.
- For 2 weeks after surgery, you should avoid vigorous sports, eye makeup, and activities that get water in the eye. The surgeon may recommend that you shower before the surgery and then avoid showering for a day or two afterward to keep from getting water in the eye.
- Dry-eye symptoms are common but usually temporary.
LASIK surgery may be used to correct mild to moderate nearsightedness. It is also considered the best procedure for correcting high myopia (greater than 7 diopters), although the results of surgery become harder to predict with higher amounts of nearsightedness.
In general, for correcting nearsightedness over 3 diopters, both LASIK and PRK are better than radial keratotomy (RK).
LASIK is an elective, cosmetic procedure that is done to correct nearsightedness in otherwise healthy eyes.
The procedure may not be done for people who:
- Have not had stable vision for at least 1 year.
- Are younger than age 18.
- Are pregnant, since that may interfere with the healing of the cornea.
- Have a disease or abnormality of the cornea, such as keratoconus or corneal edema.
- Have an uncontrolled autoimmune or connective tissue disease.
LASIK is a fairly new surgery, and little is known about the long-term outcomes. Doctors continue to improve the technique and to study the long-term results.
Over the short term, LASIK has been shown to be very effective in reducing mild to moderate nearsightedness. For people with myopia of less than 6 diopters, results show that after surgery:
- 79% to 93.5% have 20/20 vision or better.
- More than 92% have 20/40 vision or better.
For people with myopia between 6 and 12 diopters, results show that after surgery:
- 26% to 57% have 20/20 vision or better.
- 56% to 94% have 20/40 vision or better.
The risk of complications from LASIK surgery is low and decreases with a more experienced surgeon. Look for a corneal specialist or surgeon who does the surgery frequently.
Complications and side effects from LASIK may include:
- Clouded vision (clouding of the cornea as a result of healing). This is sometimes also referred to as corneal haze. This is less common with LASIK than with PRK and tends to go away quickly.
- Night vision problems, such as halos (often described as a shimmering circle around light sources such as headlights or street lamps). Some studies indicate that halo symptoms may occur less often with LASIK than with PRK surgery. 1
- Glare, or increased sensitivity to bright light.
- Double vision (diplopia), usually in one eye.
- New astigmatism caused by wrinkling in the corneal flap or other flap complications.
- Loss of best corrected vision, which is the best possible vision you can achieve using glasses or contact lenses. This may be even less common with LASIK than it is with PRK.
- Overcorrection or undercorrection.
- Development or worsening of dry-eye symptoms.
Serious vision-threatening complications are rare but may include:
- Infection of the cornea (keratitis).
- Elevated pressure inside the eye (intraocular pressure) leading to glaucoma.
Because LASIK is a new procedure, long-term risks are not yet known.
If you are considering surgery to improve nearsightedness, consider the different options (LASIK, PRK, corneal ring implants, intraocular lens implants, and radial keratotomy), and discuss them with your doctor. LASIK and PRK surgery have replaced radial keratotomy as the refractive surgeries chosen by most people.
LASIK is being done more frequently than PRK, largely because of the good results and the quick, painless visual recovery that LASIK offers. There is no agreement about whether LASIK is superior to PRK or vice versa for people with mild to moderate nearsightedness. LASIK does appear to be more effective for high myopia.
It is important to keep a record of your original eye measurements from this procedure (your doctor can give them to you), in case you need cataract surgery in the future. This is helpful in calculating future implants after cataract surgery.
LASIK is a cosmetic procedure. The cost of refractive surgery varies in different locations, but it can be a significant expense. Most insurance companies do not cover the cost of refractive surgery.
