By Mayo Clinic News Network

If you're tired of wearing eyeglasses or contact lenses, you may wonder whether laser-assisted in-situ keratomileusis (LASIK) surgery is right for you. After all, LASIK surgery has a good track record and most people are satisfied with the results.

However, LASIK surgery isn't the most appropriate vision-correction option for everyone, and it's not without risks. Read on to determine whether you're a good candidate for LASIK surgery.

When is LASIK a good choice?

LASIK surgery is a type of refractive eye surgery. During the procedure, an eye surgeon creates a flap in the cornea, and then uses a laser to reshape the cornea and correct focusing problems in the eye. LASIK surgery is most appropriate for people who have a moderate degree of:

  • Nearsightedness (myopia), in which you see nearby objects clearly, but distant objects are blurry
  • Farsightedness (hyperopia), in which you can see distant objects clearly, but nearby objects are blurry
  • Astigmatism, which causes overall blurry vision

A good surgical outcome depends on careful evaluation of your eyes before the surgery.

What about LASIK surgery for presbyopia?

By the early to mid-40s, most adults have lost some ability to focus on nearby objects (presbyopia), which results in difficulty reading small print or doing other close-up tasks. The condition may continue to worsen until about age 65.

If you have presbyopia, LASIK surgery may give you clear distance vision, but it can actually worsen your ability to see objects close up.

To maintain your ability to see close objects, you might choose to have your vision corrected for monovision. With monovision, one eye is corrected for distant vision, and the other eye is corrected for near vision. However, not everyone is able to adjust to or tolerate monovision. It's best to do a trial with contact lenses before having a permanent surgical procedure.

What are the risks of LASIK surgery?

As with any surgery, LASIK surgery carries risks, including:

  • Undercorrection, overcorrection or astigmatism. If the laser removes too little or too much tissue from your eye, you won't get the clearer vision you wanted. Similarly, uneven tissue removal can result in astigmatism.
  • Vision disturbances. After surgery you may have difficulty seeing at night. You might notice glare, halos around bright lights or double vision.
  • Dry eyes. LASIK surgery causes a temporary decrease in tear production. As your eyes heal, they might feel unusually dry.
  • Flap problems. Folding back or removing the flap from the front of your eye during surgery can cause complications, including infection, excess tears and swelling.

What increases the risks?

You're more likely to experience complications from LASIK surgery if you:

  • Have a condition that may impair your ability to heal. Diseases that affect your immune system, including autoimmune diseases (rheumatoid arthritis, lupus and others) and immunodeficiency diseases (HIV), increase the risk of incomplete healing, infection and other complications.

    Taking an immunosuppressive medication also increases the risk of a poor outcome after LASIK surgery.

  • Have persistent dry eyes. If you have dry eyes, LASIK surgery may make the condition worse.
  • Have anatomic concerns. LASIK surgery may be inappropriate if your corneas are too thin, your corneal surface is extremely irregular, or you have a condition in which the cornea thins and gradually bulges outward into a cone shape (keratoconus).
  • LASIK surgery also may not be an appropriate option if you have an abnormal lid position, deep-set eyes or other anatomic concerns.
  • Have unstable vision. You may not be eligible for LASIK surgery if the pressure inside your eye is too high or the quality of your vision is fluctuating or getting worse.
  • Are pregnant or breast-feeding. Vision can fluctuate during pregnancy and breast-feeding, making the outcome of LASIK surgery less certain.

What other circumstances make LASIK surgery a poor choice?

You might also rethink having LASIK surgery if:

  • You have severe nearsightedness. If you're nearsighted and have been diagnosed with a high refractive error, the possible benefits of LASIK surgery may not justify the risks.
  • You have fairly good vision. If you see well enough to need contacts or glasses only part of the time, improvement from the surgery may not be worth the risks.
  • You have large pupils. If your pupils are prone to opening wide in dim light, LASIK surgery may result in debilitating symptoms such as glare, halos, star bursts and ghost images.
  • You actively participate in contact sports. If you regularly receive blows to the face and eyes, such as during martial arts or boxing, LASIK surgery may not be advisable.
  • Surgery could jeopardize your career. Jobs requiring precision vision may make it inadvisable to have certain refractive procedures.
  • Cost may be an issue. Many insurance plans don't cover the cost of vision-correction surgery.