LASIK eye surgery
Alternative Names: Laser-Assisted In Situ Keratomileusis; Laser vision correction
LASIK is eye surgery that permanently changes the shape of the cornea (the clear covering on the front of the eye) in order to improve vision and reduce a person's dependency on glasses or contact lenses.
Description of Procedure
For clear vision, the eye's cornea and lens must bend (refract) light rays properly, so that images are focused clearly on the retina. Otherwise, the images will be blurry.
This blurriness is referred to as a "refractive error." It is caused by a difference between the shape of the cornea (curvature) and the length of the eye. LASIK uses an excimer laser (an ultraviolet laser) to precisely remove corneal tissue, giving it a new shape so that light rays are focused clearly on the retina. LASIK causes the cornea to be thinner.
LASIK is an outpatient surgical procedure. It will take 10 to 15 minutes to perform for each eye.
The only anesthetic used is eye drops that numb the surface of the eye. The procedure is done when you are awake, but you will get medicine to help you relax. LASIK may be done on one or both eyes during the same session.
Originally during LASIK, a special automated knife (a microkeratome) was used to cut a hinged flap of corneal tissue from the outer layer of the eyeball. Now it has become common to use a different type of laser (femtosecond) to create the corneal flap. The flap is put aside and the excimer laser is used to reshape the corneal tissue underneath.
The amount of tissue the laser will remove is calculated ahead of time. Once the reshaping is done, the surgeon replaces and secures the flap. No stitches are needed. The cornea will naturally hold the flap in place.
An eye shield or patch will be placed over the eye to protect the flap and to help prevent rubbing or pressure on the eye until it has had enough time to heal (usually overnight).
Risks of LASIK eye surgery
A small percentage of people may need to have another surgery because the condition is over- or under-corrected. Sometimes, you will still need to wear contact lenses or glasses.
Risks may include:
- Corneal infection
- Corneal scarring or permanent problems with the cornea's shape, making it impossible to wear contact lenses
- Decrease in contrast sensitivity -- even with 20/20 vision, objects may appear fuzzy or gray
- Dry eyes
- Glare or haloes
- Light sensitivity
- Night driving problems
- Patches of red or pink in the white of the eye (usually temporary)
- Reduced vision or permanent vision loss
- Scratchiness
Related Images
Learn more about LASIK eye surgery
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant STudies, University of Washington, School of Medicine; and Franklin W. Lusby, MD, Ophthalmologist, Lusby Vision Institute, La Jolla, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Copyright 2011 A.D.A.M., Inc.
