The most well known name in refractive eye surgery, LASIK (laser in situ keratomileusis) provides vision correction through the use of a laser by reshaping the cornea and changing its focusing power. Since 1993, LASIK has been performed in the United States on millions of patients with the use of a wide variety of different lasers. This procedure can be used to correct myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (misshapen cornea).
How It's Done
Before you undergo LASIK surgery, or any refractive surgery, you will be instructed to discontinue the use of contacts for 1 to 4 weeks prior to surgery to allow the cornea to return to its original shape. The day of surgery, you will go to your ophthalmologist's office or surgical center where the procedure will be performed. A mild anesthetic will be given, usually orally, before surgery, and numbing eye drops will be administered, which eliminate the element of pain, although some patients do experience some discomfort.
A small device, called a microkeratome is attached to a suction ring placed on your eye, the blade of which is used to cut a thin flap on the surface of the cornea. The flap is folded back, exposing a layer of tissue called the stroma, which is inspected for debris and dried.
Flap is created
exposing cornea tissue
You will then be asked to focus on a fixed spot as your doctor begins the laser, cutting and removing corneal tissue based on the measurements taken at the initial examination. The flap is then repositioned and left to heal. Because no stitches are used, you will be required to wear an eye patch to prevent rubbing, irritation, and pressure that might disturb the healing process.
Laser is used to
reshape cornea
Both eyes can be operated on at the same time if you are healthy enough and have ample recovery time. In some cases, however, doctors will recommend that their patient receive monovision treatment, which is the correction of only one eye for near or far vision. LASIK surgery typically takes about 5 to 10 minutes per eye.
Technology
There are now several different lasers that have received FDA approval for LASIK surgery. There are different lasers for use in myopic and hyperopic patients, but most allow for correction of astigmatism. Because the lasers are capable of vision correction within a specified refractive range, patients with uncommonly poor vision may not be a candidate for LASIK, but may benefit from other refractive procedures such as IOL implants.
Wavefront LASIK
The newest technology in LASIK is the wavefront laser. The first of these types of lasers were FDA approved in 2002. Wavefront technology sends a wave of light to the retina. The light then bounces back to a sensor, which measures the irregularities of the cornea and produces a 3-D map of the eye's visual system.
The data from the sensor is then translated into a mathematical formula that the doctor uses to program the computer that controls the refractive laser. After wavefront LASIK, 90-94% of patients enjoy 20/20 vision or better as opposed to 80% with traditional LASIK.
Recovery / Post Op Expectations
After surgery your doctor will schedule you for a follow up exam within one or two days in order to remove the eye patch and gauge recovery, and he or she may also wish to see you at periodic intervals throughout the next six months. Soreness, a burning or itching sensation, and the feeling that something is in your eye are all typical for the first several hours to few days following surgery. Vision is usually hazy or blurry for the same period of time, and tearing or watering is not uncommon.
It is important to remember to not rub your eyes as this might interfere with the healing process of the flap. Strenuous activity, contact sports, and swimming should be discontinued for the first one or two months following surgery, although you may feel comfortable enough to return to work as early as three days after surgery. Your doctor may place additional restrictions on your activity and return to work based on your individual case. If pain becomes intolerable you should see your doctor immediately.
Complications
During surgery, complications related to the cutting or hinging of the flap occur in less 0.5% of patients. Other complications occurring at less than a 1% rate include the development of an irregular astigmatism due to scarring, healing, or beam problems, infection, or other vision problems (halos around lights, blurry night vision) due to decentration, surgery performed off the center of the pupil due to surgeon error or the inability of the patient to focus on a fixed point.
Am I A Candidate?
Candidacy for LASIK surgery can vary depending on your doctor and the type of laser that is used. The minimum requirements are that a patient must be at least 18 years old and has had no drastic change in vision over the past year. For patients with severe refractive errors LASIK may not be an option, but with the advancements in refractive surgery, almost anyone with stable and healthy eyes can be treated with some type of surgery.
Cost
There has been a lot of hype and attention about the cost of LASIK surgery. Some firms claim that they can perform the surgery at a starting cost of $299 per eye. Of course, no one actually gets the surgery at that cost, and patients should beware of such advertisements; you get what you pay for. On average, the cost of LASIK is about $1,700.
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