CONDITIONS & DEFINITIONS
Photo-Refractive Keratectomy, PRK is another method of surgically reshaping the cornea using the excimer laser. The difference between LASIK and PRK is that for PRK, the corneal flap is not created. That is, the outer layer of the cornea remains in place and the laser removes tissue directly from this outer layer. During LASIK , a part of the cornea is peeled back so that the laser removes tissue from the inner corneal layers. PRK is used for low to moderate amounts of nearsightedness. Just as in LASIK, the laser treatment requires less than a minute. But unlike LASIK, the healing period time is longer. The correction for nearsightedness, farsightedness and astigmatism is the same as in LASIK. The corneal curvature is changed so that the visual images are properly focused on the back of the eye.