PRK (Photorefractive Keratectomy) is an elective, outpatient laser vision correction procedure used to improve vision and reduce or eliminate the need for eyeglasses or contact lenses. In the PRK laser vision correction procedure, the laser surgeon utilizes the excimer laser to reshape the curvature of the eye for patients with nearsightedness, farsightedness and astigmatism. PRK may be suitable for people with larger pupils, thin corneas, other corneal issues or dry eyes.
PRK vision correction surgery was introduced in the 1980s and has successfully transformed the vision of millions of people. Since the early 1990s, it has evolved into what is now known as advanced PRK, or Advanced Surface Ablation (ASA).
In all surface procedures, instead of creating a flap, the surgeon removes the cornea’s outer skin (epithelium) and uses the same laser to reshape the exposed substance of the cornea. The surface skin then grows back during the next few days.
The PRK Procedure
For the PRK laser vision correction procedure, no scalpels are used and no incisions are made. Prior to the procedure, an extremely detailed map of your eyes’ surfaces are created by a computer and then used by your NVISION laser vision correction surgeon to calibrate the excimer laser to your exact prescription. Once the laser has been properly calibrated, the technician will place an eyelid holder in your eye to keep it open throughout the procedure. The NVISION technician will insert a few anesthetic drops to numb the eye and prevent pain. To accomplish the reshaping, the surgeon first removes the protective surface layer (epithelium) from the cornea. (The epithelium is regenerated within three to five days.) Your NVISION surgeon will then smooth the area and proceed with applying computer-controlled pulses of cool laser light to reshape the curvature of the eye. Deeper cell layers remain virtually untouched.
The PRK laser vision correction process is completed in approximately 30 to 60 seconds, and immediately afterwards, a clear bandage contact lens is placed on the cornea to protect it. Additional eye drops are applied. Since a layer about as slender as a human hair is typically removed, the cornea should maintain its original strength. Often, only one eye is treated per surgery day, although your surgeon may decide to do both of your eyes on the same day.
After the PRK laser vision correction procedure, your eye may feel irritation or a foreign-body sensation for a few days, but this discomfort can usually be effectively managed with a mild pain reliever. With PRK, prescription eye drops are used for several months following the procedure. Post-operatively, PRK patients should use antibiotic drops along with anti-inflammatory agents to promote comfort and reduce swelling. PRK patients are also fitted with bandage contact lenses to improve their comfort while their eyes are healing. Once the epithelium is healed, usually on the second or third post-operative day, the bandage contact lens is removed by your NVISION doctor. To complete the healing process, PRK patients use steroid anti-inflammatory drops for approximately two months under the direct supervision of their eye doctors.
At NVISION Laser Eye Centers, risks of the surgery are discussed with the patient prior to the procedure. Proper pre-operative screening and testing ensures that you are considered a candidate only when it is medically advisable. As well, diligent post-operative care helps to identify and address potential healing complications.