LASIK is the most commonly performed laser eye surgery to treat myopia (nearsightedness), hyperopia (farsightedness) and astigmatism.
The word "LASIK" is an acronym for "laser-assisted in situ keratomileusis."
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.
LASIK surgery is essentially pain-free and takes only about 20 minutes for both eyes. The results — improved vision without eyeglasses or contact lenses — begin immediately after the procedure and vision usually continues to improve and stabilize over a few days.
How is LASIK surgery performed?
First, your LASIK surgeon will create a very thin, superficial flap in your cornea with a small surgical tool called a microkeratome or with a femtosecond laser if you have opted for the Femto Lasik procedure.
The surgeon then folds back the hinged flap to access the underlying cornea and removes some corneal tissue using an excimer laser.
Excimer lasers create a cool ultraviolet light beam to remove ("ablate") microscopic amounts of tissue from the cornea to reshape it so light entering the eye focuses more accurately 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.
After the laser ablation reshapes the cornea, the flap is then laid back in place, covering the area where the corneal tissue was removed. The flap seals to the underlying cornea during the healing period following surgery.
LASIK laser eye surgery requires only topical anesthetic drops, and no bandages or stitches are required.
Before LASIK surgery
Your eye doctor will perform a thorough eye exam to ensure your eyes are healthy enough for the procedure. He or she will evaluate: the shape and thickness of your cornea; pupil size; refractive errors (myopia, hyperopia and astigmatism); as well as any other eye conditions.
Usually, an automated instrument called a corneal topographer is used to measure the curvature of the front surface of your eye and create a "map" of your cornea.
Your eye doctor also will ask you about your general health history and any medications you are taking to determine if you are a suitable candidate for LASIK.
You should stop wearing contact lenses for a period of time advised by your doctor (typically around one or two weeks) before your eye exam and before the LASIK procedure. This is because contact lens wear can temporarily alter the natural shape of your cornea.
What to expect during LASIK
Before your LASIK surgery begins, numbing eye drops are applied to your eye to prevent any discomfort during the procedure.
Your eye will be positioned under the laser, and an instrument called a lid speculum is used to keep your eyelids wide open.
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 your surgeon watches your eye through a microscope as the laser sends pulses of light to your cornea.
The laser light pulses painlessly reshape the cornea. LASIK is performed on each eye separately, with each procedure taking only about ten minutes.
Immediately after LASIK surgery
Upon completion of your LASIK procedure, your surgeon will have you rest for a bit. After a brief post-operative exam, someone can drive you home.
You may be able to go to work the next day, but some doctors advise at least one day of rest instead.
Also, it is usually recommended that you refrain from any strenuous exercise for at least a week, since this can traumatize the eye and affect healing.
Generally, you will return to see your eye doctor or your LASIK surgeon the day after surgery.
As with any other surgery, it's very important for you to follow your doctor's instructions and take any medication prescribed.
Also, avoid rubbing your eyes, as there's a small chance you could dislodge the corneal flap if you rub your eyes vigorously before the flap has securely reattached to the underlying cornea stroma.
Long-term results
Laser eye surgery offers numerous benefits and can dramatically improve your quality of life.
Most people achieve 20/20 vision or better after the surgery.
This post originally appeared on All About Vision.