Laser Vision Correction
PRK (Photorefractive Keratectomy)
Photorefractive keratectomy, or PRK, is a laser vision correction procedure that reshapes the cornea to correct mild to moderate conditions of:
- Nearsightedness, or myopia
- Farsightedness, or hyperopia
PRK uses an excimer laser to remove a small amount of the anterior portion, or front, of the cornea to correct refractive errors. Unlike the LASIK procedure, where a flap is created to access the cornea, PRK removes the epithelial, or outer layer, of the cornea so that it can be reshaped using an excimer laser to remove tissue from the surface. This process flattens the cornea and achieves the corneal steepening needed for vision correction.
Advantages of the Photorefractive Keratectomy Procedure
The PRK procedure provides the surgeon with greater control over the location and amount of tissue being removed, which allows patients to enjoy much more accurate results. The PRK method involves gently sculpting the cornea rather than cutting, allowing the surgeon to treat greater degrees of nearsightedness, as well as farsightedness and astigmatism. Visual results are comparable to Lasik.
Some of the advantages of the PRK procedure include:
- Less depth of laser treatment
- Patients with thin corneas are eligible for PRK
- No corneal flap complications
Candidates for the Photorefractive Keratectomy Procedure
Before LASIK was available, PRK was the most commonly performed refractive surgery procedure. LASIK has several advantages over PRK, including: less discomfort, faster results and quicker recovery. PRK is preferred for people with thin corneas, certain corneal conditions and dry eyes.
The Photorefractive Keratectomy Procedure
Before the PRK procedure begins, the eyes are numbed with anesthetic eye drops. The surgeon uses targeted laser energy to then correctly shape the cornea. The surgeon will have complete control over the laser, throughout the procedure, for a highly precise and customized result designed to give each patient the best vision possible. The entire procedure takes only a few minutes to perform.
After the procedure, the eyes will be bandaged with a soft contact lens so that the cornea is protected. New cells, to replace the cells that were removed, will grow back over the next few days. The contact lens will be removed by the surgeon in a follow up examination.
Recovery from the Photorefractive Keratectomy Procedure
After the PRK procedure is completed, patients will need to rest before returning to their home. Patients may need to wear bandage contact lenses for several days. Pain meds may be necessary for some patients. Patients may need several days to see well enough to return to work and drive. The surgeon will prescribe topical antibiotics to prevent infection and to keep the eyes moisturized.
While vision may seem to have improved initially, full results may take several days or weeks to see full improvement. Patients may be able to return to work the next day, unless otherwise advised. Strenuous exercise should be avoided for at least a week, as this can affect the healing process. You will likely be able to see well enough to drive a car after two or three weeks.
Results of the Photorefractive Keratectomy Procedure
The results of PRK are considered comparable to those of LASIK, although some patients may experience vision of only 20/40, and others may still need glasses or contact lenses after their procedure. PRK does not correct presbyopia, a natural change in the eyes that affects everyone over the age of 40, so patients that need reading glasses will continue to need them after surgery. While it takes a little longer to reach final vision, safety is the most important factor.
Risks of Photorefractive Keratectomy
As with any type of surgery, there are certain risks associated with the PRK procedure, including:
- Reaction to anesthesia
- Sensitivity to light
- Undercorrection or overcorrection
- Hazy vision