Laser vision correction

PRK (photorefractive keratectomy), LASEK (laser epithelial keratomileusis), and epi-LASIK (epithelial laser in-situ keratomileusis) use a laser to reshape the cornea. By reshaping the cornea, these surgeries allow light to focus on the retina. This corrects a person's vision.

With PRK, the top layer on the surface of the cornea (epithelium) is removed. Then the laser reshapes the cornea. The laser removes tissue from the cornea very accurately. It doesn't damage nearby tissues. The layer grows back during the healing process. PRK may be used to correct nearsightedness and astigmatism at the same time.

With LASEK, the surface layer of the cornea is loosened and pushed to the side. After the laser reshapes the cornea, the surface layer is put back in place.

Epi-LASIK is similar to PRK and LASEK. With epi-LASIK, the surface layer over the cornea is lifted with a special machine. Like LASEK, the layer is replaced over the cornea after the laser reshapes the cornea.

These procedures don't require a hospital stay. They are done under local anesthesia in a surgeon's office or a same-day surgery center. The procedure takes about 30 minutes. Most of this time is spent preparing your eye and the laser. The actual treatment time is very short. The entire process may take about 2 hours, including preparation time, care right after the surgery, and paperwork.

PRK, LASEK, and epi-LASIK are sometimes called surface ablation. They are different from LASIK (laser in-situ keratomileusis) because they don't involve cutting flaps of the cornea.

Many people have PRK or LASEK done instead of LASIK because of the shape and condition of their eyes. PRK or LASEK may also be safer for people with certain lifestyles, such as professional athletes, police officers, and firefighters.

PRK, LASEK, and epi-LASIK are all procedures that correct nearsightedness in otherwise healthy eyes.

They may not be the right choice for people who have more severe nearsightedness (high myopia). That's because the results are harder to predict, complications are more likely, and regression is more likely. Also, PRK may not be right for you if you have keloids.

The procedure may not be done during pregnancy or breastfeeding. You also may not be eligible for the surgery if you have an uncontrolled autoimmune or connective tissue disease.

PRK, LASEK, and epi-LASIK work well to reduce mild to moderate nearsightedness.

Overall, the results of these surgeries are stable over the long term. The results have improved as techniques and lasers have evolved and changed.

Almost everyone notices improvements in their vision after one of these surgeries. But not everyone gets perfect 20/20 vision. Studies show that after PRK or LASEK:

• More than 94 out of 100 people have 20/40 vision or better.
• More than 61 out of 100 people who had PRK and more than 74 out of 100 people who had LASEK have 20/20 vision or better.

In a study done one year after epi-LASIK treatment, all of the people's eyes had 20/40 vision or better. And more than 3 out of 4 eyes had 20/20 vision or better.

In general, most people with mild or moderate nearsightedness can expect to have uncorrected vision of 20/40 or better (without glasses or contacts) after surgery. Results in people who are more nearsighted are harder to predict.