Photorefractive keratectomy (PRK) is a type of eye surgery that uses a laser to change the shape of the cornea. The cornea is the clear outer layer on the front of the eye.
When is it used?
PRK is used to correct problems with your vision and reduce your need for glasses or contact lenses. After their eyes heal, many people have 20/40 vision or better after PRK. Be sure to talk to your provider about how much improvement in your vision you can realistically expect.
PRK may be used to treat:
Mild to moderately severe nearsightedness. Nearsightedness means that you see close objects clearly, but distant objects are blurry. This happens when the eyeball is too long or when the outer layer of the eye, called the cornea, is too curved. This causes light rays to focus at a point in front of the light-sensitive tissue at the back of the eye (retina) instead of directly on it.
Mild farsightedness. Farsightedness is when you see distant objects clearly, but close objects are blurry. This happens when the shape of your eyeball causes light rays to focus in the wrong place at the back of your eye.
Astigmatism. Astigmatism is blurred vision caused by an uneven curve in your cornea. The cornea is the clear outer layer on the front of the eye. As a result of astigmatism, your vision is somewhat blurry both close up and far away.
Usually one eye is done at a time.
Ask your healthcare provider about your choices for treatment and the risks.
How do I prepare for this procedure?
Plan for your care and a ride home after the procedure.
You may or may not need to take your regular medicines the day of the procedure. Tell your healthcare provider about all medicines and supplements that you take. Some products may increase your risk of side effects. Ask your healthcare provider if you need to avoid taking any medicine or supplements before the procedure.
Do not wear eye makeup, perfume, or cologne on the day of the surgery.
Follow any other instructions your healthcare provider gives you.
Ask any questions you have before the procedure. You should understand what your healthcare provider is going to do. You have the right to make decisions about your healthcare and to give permission for any tests or procedures.
What happens during the procedure?
The surgery is done in an office or a surgical center with laser equipment. The provider numbs your eye with eyedrops. He or she polishes away the outer layer of the cornea. Then the provider uses a special laser to remove thin layers of tissue inside the cornea until it is the right shape to improve your vision. The removal of tissue changes the shape of the cornea so that light rays can focus on or closer to the retina, which improves your vision.
Often a contact lens will be placed in your eye after surgery to protect the surface of the eye and to help with the discomfort while the eye heals. Your provider will remove the contact 3 or 4 days after the eye has healed.
What happens after the procedure?
Your eyes may hurt until the outer layer of the cornea grows back. This takes about 3 to 7 days. Your vision may be hazy during this time. Ask your provider about medicines to reduce your discomfort.
Your vision may continue to change for several months. If needed, your eye care provider can repeat the surgery to improve your vision.
Ask your healthcare provider:
How long it will take to recover
What activities you should avoid
How to take care of yourself at home and when you can return to your normal activities
What symptoms or problems you should watch for and what to do if you have them
Make sure you know when you should come back for a checkup.
What are the risks of PRK?
Your healthcare provider will explain the procedure and any risks. Some possible risks include:
Your eyes may be over-corrected or under-corrected, and you may still need glasses.
You may have scarring that causes glare or an irregular astigmatism. This can cause blurry vision, particularly at night.
You may need glasses for close vision or driving at night. After PRK, some people need to start using reading glasses sooner than they would have without it. (Most people need reading glasses after about age 40 because of normal changes in their eyes.)
In rare cases, the cornea gets severely inflamed, called keratitis. This may need treatment with eyedrops or more surgery.
Very rarely, you may get an infection, which can cause your vision to be worse than it was before the procedure.
Your eyes may become more sensitive to light. Also, you may see halos around lights or other unusual effects. These effects are due to light coming through the cut edges of the cornea. Some of these problems go away after your eyes heal, but some do not.
Every procedure or treatment has risks. Ask your healthcare provider how these risks apply to you. Be sure to discuss any other questions or concerns that you may have.
Adult Advisor 2015.1 published by RelayHealth. Last modified: 2014-10-28 Last reviewed: 2014-10-28
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
PRK Laser Surgery: References
American Academy of Ophthalmology. 2013-2014 Basic and Clinical Science Course. San Francisco: American Academy of Ophthalmology, 2013; v.1-13.