LASIK (laser-assisted in-situ keratomileusis) is an outpatient surgical procedure used to treat nearsightedness, farsightedness, and astigmatism, and reduce or eliminate the need for eyeglasses or contact lenses.

During the 30-minute or less procedure, an ophthalmologist uses a laser to reshape the cornea at the front of the eye to improve the eye’s ability to focus light rays onto the retina at the back of the eye.

Since LASIK was first approved for use by the FDA in 1998, it has become one of the most widely performed outpatient surgeries in the United States. About 700,000 Americans undergo LASIK each year, and more than 90 percent of them achieve between 20/20 and 20/40 vision without eyeglasses or contact lenses.

Although most LASIK patients are satisfied with the results, LASIK isn’t for everyone. If you have certain eye conditions or other health problems, you may not be a good candidate for the procedure.

LASIK, like any other surgery, is associated with certain side effects and complications. Although the rate of serious complications is extremely low, some LASIK patients do experience complications that adversely affect their eyes and quality of life. In some cases, it’s necessary to undergo repeat LASIK procedures.

It’s also important to recognize that LASIK has certain limitations. For example, it cannot reverse presbyopia, the age-related loss of close-up focusing power that almost everyone develops in their 40s and 50s. So even if LASIK successfully treats your nearsightedness, farsightedness, or astigmatism, you’ll still probably need to wear reading glasses after reaching middle age. In addition, you still may need to wear eyeglasses or contact lenses for certain activities such as driving at night.

Another important factor is cost. Because LASIK is considered an elective surgery, insurers generally don’t cover it. So you’ll probably need to pay the entire expense – which can amount to several thousand dollars – out of your own pocket.

Are You a Good Candidate for LASIK?

Before you can proceed with LASIK, your doctor will perform a complete eye examination, take your medical history, review your medications, and ask about your work, recreational, and leisure activities. If you participate in certain activities such as contact sports, you may be advised to forgo LASIK.

LASIK may not be for you if you have these risk factors:

• Dry eye syndrome.
• Large pupil size.
• Keratoconus, a degenerative corneal condition, or a family history of this disorder.
• Very high levels of refractive error or certain combinations of errors.
• Unstable vision (a correction prescription that has not remained the same for about a year).
• Younger age. Patients under age 21 are generally not good candidates because their refractive error is likely to be changing. But older patients may still be experiencing changes in refractive error that make them unsuitable candidates.
• Pregnancy.
• Other health conditions. These include autoimmune disorders, such as rheumatoid arthritis, and immunodeficiency conditions caused by immunosuppressive medications or HIV.

What to Expect During and After LASIK

During the procedure, you lay on your back while your doctor places numbing drops in your eye or eyes, uses a special instrument to keep your eyelids open, and places a suction ring on your eye. Then your doctor uses a special blade or laser to cut a hinged flap in the front of the eye, folds it back, and asks you to focus on a point of light while he or she uses a laser to reshape the cornea. You may detect a burning odor during the procedure, which is normal. After the reshaping is complete, your doctor folds the flap back into place.

After the procedure, you’re likely to experiencing burning, itching, or watery eyes, and blurred vision. So you’ll need to arrange for someone else to drive you home.  Your doctor may give you eyedrops to relieve discomfort, and recommend that you wear an eye shield during sleep.

One or two days after the procedure, you’ll return to your doctor for a follow-up assessment and will need additional assessments during the next six months. LASIK-treated eyes generally take about two to three months to heal and achieve stable vision.

LASIK Side Effects and Complications

Like any surgical procedure, LASIK carries a risk inflammation and infection, which usually can be treated with medications. Complications that may need further surgical treatment include:

• Problems with the corneal flap.
• Ectasia, or bulging of the cornea.
• Significantly reduced vision.
• Over- or under-correction of the refractive error.
• Reduction over time in the refractive correction.

Although permanent vision loss can occur after LASIK, this is an extremely rare complication.

The most common side effects and complications usually subside within three to six months after the procedure, but sometimes may be permanent. These include:

• Discomfort or pain.
• Dry eye.
• Hazy or blurry vision.
• Poor night vision or difficulty driving at night.
• Glare, halos, or starbursts around light.
• Sensitivity to light.
• Contrast sensitivity (reduced sharpness of vision).
• Small pink or red patches on the white of the eye.

The American Academy of Ophthalmology and the International Society of Refractive Surgery have developed a comprehensive guide for prospective patients:  “Is LASIK for Me? A Patient’s Guide to Refractive Surgery.”  You can access the guide at: http://www.geteyesmart.org/eyesmart/glasses-contacts-lasik/upload/lasik-patient-guide.pdf