Produced in cooperation with the American Academy of Ophthalmology.

If you're tired of wearing glasses or contact lenses, you may be considering Lasik eye surgery — one of the newest procedures to correct vision problems. Before you sign up for the surgery, get a clear picture of what you can expect.

Facts

Lasik is surgery to a very delicate part of the eye. Hundreds of thousands of people have had Lasik, most very successfully. As with any surgery, there are risks and possible complications. Lasik may not give you perfect vision. The American Academy of Ophthalmology (AAO) reports that seven out of 10 patients achieve 20/20 vision, but 20/20 does not always mean perfect vision. If you have Lasik to correct your distance vision, you'll still need reading glasses around age 45. Lasik surgery is too new to know if there are any long-term ill effects beyond five years after surgery. Lasik surgery cannot be reversed. Most insurance does not cover the surgery. You may need additional surgery — called "enhancements" — to get the best possible vision after Lasik.

Lasik is not for everyone.

• You should be at least 18 years old (21 for some lasers), since the vision of people younger than 18 usually continues to change.
• You should not be pregnant or nursing as these conditions might change the measured refraction of the eye.
• You should not be taking certain prescription drugs, such as Accutane or oral prednisone.
• Your eyes must be healthy and your prescription stable. If you're myopic, you should postpone Lasik until your refraction has stabilized, as myopia may continue to increase in some patients until their mid- to late 20s.
• You should be in good general health. Lasik may not be recommended for patients with diabetes, rheumatoid arthritis, lupus, glaucoma, herpes infections of the eye, or cataracts. You should discuss this with your surgeon.
• Weigh the risks and rewards. If you're happy wearing contacts or glasses, you may want to forego the surgery.
• Understand your expectations from the surgery. Are they realistic?
• Ask your doctor if you're a candidate for monovision — correcting one eye for distance vision and the other eye for near vision. If you can adjust to this correction, it may eliminate or reduce your need for reading glasses. In some instances, surgery on only one eye is required. If your doctor thinks you're a candidate, ask about the pros and cons.

Before the surgery, your surgeon should explain to you the risks and possible complications, and potential side effects, including the pros and cons of having one or both eyes done on the same day. This is the "informed consent" process. The procedure is very safe and effective for the vast majority of people. A good screening process will increase the likelihood of a good outcome. Some risks and possible complications include:

• Over- or under-correction. These problems can often be improved with glasses, contact lenses and enhancements.
• Corneal scarring, irregular astigmatism (permanent warping of the cornea), and an inability to wear contact lenses.
• Corneal infection.
• "Loss of best corrected visual acuity" — that is, you would not be able to see as well after surgery, even with glasses or contacts, as you did with glasses or contacts before surgery.
• A decrease in contrast sensitivity, "crispness," or sharpness. That means that even though you may have 20/20 vision, objects may appear fuzzy or grayish.
• Problems with night driving that may require glasses.
• Flap problems, including: irregular flaps, incomplete flaps, flaps cut off entirely, and ingrowth of cells under the flap.

The following side effects are possible, but usually disappear over time. In rare situations, they may be permanent.

• Discomfort or pain
• Hazy or blurry vision
• Scratchiness
• Dryness
• Glare
• Haloes or starbursts around lights
• Light sensitivity

Before:
You'll need a complete eye examination by your refractive surgeon. A preliminary eye exam may be performed by a referring doctor (Eye MD or optometrist). Take your eye prescription records with you to the exams. Your doctor should:

• Dilate your pupils to fine-tune your prescription.
• Examine your eyes to make sure they're healthy. This includes a glaucoma test and a retina exam.
• Take the following measurements:
• The curvature of your cornea and your pupils. You may be rejected if your pupils are too large.
• The topography of your eyes to make sure you don't have an irregular astigmatism or a cone-shaped cornea — a condition called Keratoconus.
• The pachymetry — or thickness — of your cornea. You need to have enough tissue left after your corneas have been cut and reshaped.
• Ask you to sign an informed consent form after a thorough discussion of the risks, benefits, alternative options and possible complications. Review the form carefully. Don't sign until you understand everything in the form.
• If your doctor doesn't think Lasik is right for you, you might consider getting a second opinion; however, if the opinion is the same, believe it.

If you qualify for surgery, your doctor may tell you to stop wearing your contact lenses for a while before the surgery is scheduled because contacts can temporarily change the shape of the cornea. Your cornea should be in its natural shape the day of surgery. Your doctor also may tell you to stop wearing makeup, lotions or perfume for a few days before surgery. These products can interfere with the laser treatment or increase the risk of infection after surgery.

During
Lasik is an outpatient surgical procedure. The only anesthetic is an eye drop that numbs the surface of the eye. The surgery takes 10 to15 minutes for each eye. Sometimes, both eyes are done during the same procedure; but sometimes, surgeons wait to see the result of the first eye before doing the second eye.

The Surgical Procedure:
A special device cuts a hinged flap of thin corneal tissue off the outer layer of the eyeball (cornea) and the flap is lifted out of the way. The laser reshapes the underlying corneal tissue, and the surgeon replaces the flap, which quickly adheres to the eyeball. There are no stitches. A shield — either clear plastic or perforated metal — is placed over the eye to protect the flap.

After
Healing is relatively fast, but you may want to take a few days off after the surgery. Be aware that:

• You may experience a mild burning or sensation for a few hours after surgery. Do not rub your eye(s). Your doctor can prescribe a painkiller, if necessary, to ease the discomfort.
• Your vision probably will be blurry the day of surgery, but it will improve considerably by the next day when you return for a follow-up exam.
• If you experience aggravating or unusual side effects, report them to your doctor immediately.
• Do not drive until your vision has improved enough to safely do so.