Photorefractive keratectomy (PRK) is an out-patient surgical procedure used to correct refractive errors (myopia, hyperopia, astigmatism) and to reduce dependency on glasses or contact lenses. PRK uses a laser to reshape the cornea and to improve the way the eye focuses light onto the retina.
PRK used to be the most common refractive procedure and it is still indicated for certain patients.
PRK is suitable for most patients but your ophthalmologist will advise you about certain conditions that may prevent you from being a good candidate for this procedure. Therefore, any medical conditions you may have (for example progressive eye diseases or systemic diseases causing dry eyes) are vital information for your ophthalmologist.
Patients for PRK should be over 18 years of age with a stable glass prescription for at least one year. Depending on the power of your glasses, corneal thickness and other characteristics of your cornea, you may be advised to have PRK rather than other types of vision corrective surgery to get rid of your glasses. A thin cornea is one such instance.
Your surgeon may prescribe you eye drops or suggest treatment of any underlying eye disease in preparation for your surgery. Soft contact lenses should not be used for one week and hard contact lenses should not be used for 3-4 weeks prior to the operation. Patients should not use eye make-up on the day of the surgery.
PRK is preformed with the patient in a lying position in an outpatient surgical suite. Before entering the suite, the eye area is cleaned and a surgical cap is placed to cover the patient's hair. You get the first eye drops before entering the suite with more drops throughout the procedure including anesthetic drops to avoid discomfort. These drops may sting briefly. An eyelid holder is placed between the eyelids to keep them open and prevent you from blinking. While one is being operated, the other is covered.
The epithelium (superficial layer of the cornea) is gently removed to reveal the surface to be laser-treated. A special laser for sculpting the area, pre-programmed with measurements customized for your eyes, is centered above the eye. A pupil tracker is used to keep the laser centered on your pupil during surgery. You will be instructed to stare at a green blinking light while the laser sculpts the exposed corneal tissue. You will hear the buzzing of the laser and you may notice a burning smell. Both are a normal part of the procedure. After the laser has completed reshaping the cornea, the surgeon places a bandage contact lens for 3-5 days to help the healing process and to facilitate the re-growth of the epithelium. You will be fully conscious throughout the procedure, which lasts approximately 5-7 minutes per eye.
You will be escorted to a recovery room to rest for a while after which your eyes will be checked. After the check you may go home but you will need someone to take you as you will not be able to drive. It is advised to use dark glasses on your way home as bright lights may feel uncomfortable. These glasses should be used for one week (at night) to avoid accidental scratching or rubbing. You will be instructed to use eye drops to avoid infections, speed the healing process and moisten the cornea. Please do not leave the clinic before your eyes have been examined and the post-operative appointment has been given.
With an experienced doctor and careful patient selection, complications (listed below) are rare and can usually be treated without any loss of vision. Some of these complications may require extra medications or further procedures (lacrimal plugs, glasses, contact lenses, corneal cross-linking, re-operation, corneal graft).
You will be given sick leave for 3-5 days due to discomfort/foreign body sensation, which can be quite unpleasant. Swimming and heavy exercise should be avoided for two weeks and eye make-up should not be used for one week after the operation. Please speak with your surgeon if you have any concerns.
Follow-up visits are recommended 3-5 days later to remove the bandage contact lens, during the second week after the operation and in 3 months. Sometimes more visits are advised depending on individual circumstances.