Like other types of refractive surgery, the LASIK procedure reshapes the cornea to enable light entering the eye to be properly focused onto the retina for clearer vision.
In most cases, laser eye surgery is pain-free and completed within 15 minutes for both eyes. The results — improved vision without eyeglasses or contact lenses — can usually be seen in as little as 24 hours.
First, your eye surgeon uses either a mechanical surgical tool called a microkeratome or a femtosecond laser to create a thin, circular “flap” in the cornea.
The surgeon then folds back the hinged flap to access the underlying cornea (called the stroma) and removes some corneal tissue using an excimer laser.
This highly specialized laser uses a cool ultraviolet light beam to remove (“ablate”) microscopic amounts of tissue from the cornea to reshape it so it more accurately focuses light on the retina for improved vision.
For nearsighted people, the goal is to flatten the cornea; with farsighted people, a steeper cornea is desired.
Excimer lasers also can correct astigmatism by smoothing an irregular cornea into a more normal shape. It is a misconception that LASIK cannot treat astigmatism.
After the laser reshapes the cornea, the flap is then laid back in place, covering the area where the corneal tissue was removed. Then the cornea is allowed to heal naturally.
Laser eye surgery requires only topical anesthetic drops, and no bandages or stitches are required.
Before your surgery begins, numbing eye drops are applied to your eye to prevent any discomfort during the procedure. Your doctor may also give you some medication to help you relax.
Your eye will be positioned under the laser, and an instrument called a lid speculum is used to keep your eyelids open.
The surgeon uses an ink marker to mark the cornea before creating the flap. A suction ring is applied to the front of your eye to prevent eye movements or loss of contact that could affect flap quality.
After the corneal flap is created, the surgeon then uses a computer to adjust the excimer laser for your particular prescription.
You will be asked to look at a target light for a short time while he or she watches your eye through a microscope as the laser sends pulses of light to your cornea.
The laser light pulses painlessly reshape the cornea, although you may feel some pressure on your eye. You’ll also hear a steady clicking sound while the laser is operating.
LASIK is performed on each eye separately, with each procedure taking only about five minutes.