LASIK is the most commonly performed laser eye surgery to treat myopia (nearsightedness), hyperopia (farsightedness) and astigmatism.
Nearsightedness (myopia). When your eyeball is slightly longer than normal or when the cornea curves too sharply, light rays focus in front of the retina and blur distant vision. You can see objects that are close fairly clearly, but not those that are far away.
Farsightedness (hyperopia). When you have a shorter than average eyeball or a cornea that is too flat, light focuses behind the retina instead of on it. This makes near vision, and sometimes distant vision, blurry.
Astigmatism. When the cornea curves or flattens unevenly, the result is astigmatism, which disrupts focus of near and distant vision.
During the procedure
LASIK surgery is usually completed in 30 minutes or less. After numbing drops are placed in your eye, your doctor uses an instrument to hold your eyelids open. A suction ring placed on your eye just before cutting the corneal flap may cause a feeling of pressure, and your vision may dim a little.Your eye surgeon uses a small blade or cutting laser to cut a small hinged flap away from the front of your eye.
Using a programmed laser, your eye surgeon reshapes parts of your cornea. With each pulse of the laser beam, a tiny amount of corneal tissue is removed. After reshaping the cornea, the surgeon lays the flap back into place. The flap usually heals without stitches.
During the surgery, you'll be asked to focus on a point of light. Staring at this light helps you keep your eye fixed while the laser reshapes your cornea. If you need LASIK surgery in both eyes, doctors will generally conduct the procedure on the same day.
People who are suitable for LASIK
LASIK can correct myopia up to 1400 degrees, hyperopia up to 600 degrees and astigmatism up to 600 degrees. The ophthalmologist will make a detailed examination before correction, to ensure the patient is suitable for laser eye surgery. If there is a transient eye dry condition, the doctor will use moisturizing eye drops to solve the problem and the eye will usually return to normal water secretion in a few weeks after surgery. However, if the cornea is too thin, the pupils are too large, or there are other issues that render the patient unsuitable for LASIK, there are other methods available, such as implantable contact lenses or ReLEx SMILE Small Incision Lenticule Extraction.
LASIK often offers improved vision without the hassle of glasses or contact lenses. In general, you have a very good chance of achieving 20/25 vision or better after refractive surgery. More than 8 out of 10 people who've undergone LASIK refractive surgery no longer need to use their glasses or contact lenses for most of their activities.
Your results depend on your specific refractive error and other factors. People with a low grade of nearsightedness tend to have the most success with refractive surgery. People with a high degree of nearsightedness or farsightedness along with astigmatism have less predictable results.
In some cases, the surgery might result in undercorrection. If this happens, you might need another surgery to achieve the proper correction. Rarely, some people's eyes slowly return to the level of vision they had before surgery. This might happen due to certain conditions, such as abnormal wound healing, hormonal imbalances or pregnancy. Sometimes this change in vision is due to another eye problem, such as a cataract. Talk with your doctor about any vision changes.