PRK stands for photorefractive keratectomy, but simply put, it is a technique for laser vision correction. PRK was actually the first laser procedure for vision correction (even before LASIK). It is a type of refractive surgery that is used to correct several vision problems including nearsightedness, farsightedness, and astigmatism.
In PRK, the surface layer of cells are removed gently with a sponge after being soaked in alcohol. An excimer laser then sculpts the underlying stromal layer of the cornea to allow light to focus appropriately without spectacles, thus promoting clearer vision. After the procedure, a temporary contact lens is placed onto the eye, allowing new epithelial cells to regenerate and heal. The lens is then removed three to four days after surgery.
Unlike LASIK, PRK does not create a corneal flap, containing both epithelial and the deeper stromal tissue. This allows the entire thickness of the underlying stroma to be treated. This is particularly beneficial to patients whose cornea is too thin for LASIK.
Most patients do very well after undergoing PRK. The procedure is an excellent, lower risk method, of correcting vision.