PRK (photorefractive keratectomy) is a procedure to reshape corneal tissue to help you see better without glasses or corrective lenses. This procedure uses an excimer laser. This laser produces a concentrated beam of cool ultraviolet (UV) light. Each pulse of the laser can remove a tiny portion of corneal tissue. PRK can be used to treat low to moderate myopia (nearsighted), hyperopia (farsightedness), and astigmatism (vision distortions caused by irregularities in the cornea).
Before treatment, you may be given medication to help you relax.
Eyedrops numb your eyes. A device is used to keep your eyes open.
A small surgical tool or the laser is first used to remove the central portion of the epithelium. Laser treatment lasts for 10–90 seconds.
After laser treatment, you will wear a contact lens as a bandage for a few days. This protects the cornea as it heals.
For a few days after the procedure, your vision may seem worse. It should begin to improve in about 5 days, and become stable in about 6 months.
Mild to moderate pain after surgery
Longer vision recovery than LASIK
May need to use eyedrops for 3 months or longer
Risk of corneal scarring or haze
Risk of temporary or permanent dry eye
Risk of night vision problems, such as halos, glare, or starbursts
Risk of undercorrection or overcorrection
Risk of loss of best corrected vision
No risk of flap complications
Better for people with thin corneas, previous glaucoma surgery, mild corneal scars, or other cornea problems