What is PRK?

Like LASIK, PRK uses an excimer laser to treat nearsightedness, farsightedness, and astigmatism. Unlike LASIK, PRK is performed on the surface of the cornea, rather than on the inner corneal layers.

DR. LAWRENCE ZWEIBEL: With PRK we're accomplishing the same thing we do with LASIK. We're reshaping the cornea of the eye. The main difference between PRK and LASIK is with PRK no flap is created. Because no flap is created, we're even able to maintain more of the corneal integrity than with LASIK. But the disadvantage of PRK is that because no flap is made there's a big surface of epithelial cells that have to be removed before we can reshape your cornea. And it takes about two to four days for these epithelial cells to repopulate the area where they were removed from. During this period we use contact lenses. The vision usually is in the range of about 20/40 to 20/70 during this period. Following that, after the contact lens is removed, the epithelial cells gradually smooth out and the vision drops down to approximately the 20/20 level within about ten days.