Photorefractive Keratectomy Eye Surgery
Photorefractive keratectomy, or PRK, is a type of laser eye surgery used to correct mild to moderate nearsightedness, farsightedness, and/or astigmatism.
All laser vision correction surgeries work by reshaping the cornea, or clear front part of the eye, so that light traveling through it is properly focused onto the retina located in the back of the eye. There are a number of different surgical techniques used to reshape the cornea. During PRK, an eye surgeon uses a laser to reshape the cornea. This laser, which delivers a cool pulsing beam of ultraviolet light, is used on the surface of the cornea, not underneath the cornea, as in LASIK.
What Are the Advantages of PRK Eye Surgery?
PRK eye surgery is highly accurate in correcting many cases of nearsightedness. Approximately 80% to 90% of PRK patients have 20/20 vision without glasses or contact lenses one year after the surgery; 95% to 98% have 20/40 or better without glasses or contacts.
What Are the Disadvantages of PRK Eye Surgery?
Disadvantages of PRK eye surgery include:
- Mild discomfort, including minor eye irritation and watering, for one to three days following the procedure.
- Somewhat longer time than LASIK to best uncorrected vision (best vision is vision attained using glasses or contacts). Typically patients are 80% at one month after surgery, and 95%-100% by three months after surgery. LASIK, in contrast, corrects vision much faster.
- Some patients may still require glasses after PRK.
What Are the Potential Side Effects of PRK Eye Surgery?
PRK patients typically experience mild discomfort in the first 24 to 48 hours after surgery and almost all experience sensitivity to light. Within the first six months after surgery, other potential side effects may include:
- Loss of best vision with or without glasses.
- Mild glare can be permanent, depending on a patient's pupil size in dim light.
- Mild halos around images.
How Do I Prepare for PRK Eye Surgery?
Before your PRK eye surgery you will meet with an eye surgeon or a coordinator who will discuss with you what you should expect during and after the surgery. During this session your medical history will be evaluated and your eyes will be tested. Likely tests include measuring corneal thickness, refraction, corneal mapping, air pressure, and pupil dilation. Once you have gone through your evaluation, your surgeon will answer any questions you may have. Afterwards, you can schedule an appointment for the PRK procedure.
If you wear rigid gas permeable contact lenses, you should not wear them starting three weeks before your evaluation. Other types of contact lenses shouldn't be worn for at least three days prior to the evaluation as well.
On the day of your surgery, eat a light meal before coming and take all of your prescribed medications. Do not wear eye makeup or have any bulky accessories in your hair that will interfere with positioning your head under the laser. If you are not feeling well that morning, call the doctor's office to determine whether the procedure needs to be postponed.