To correct for astigmatism, selected tissue at certain angles is removed to insure that the cornea curves equally in all directions. After the laser has been used, the flap is returned to its original position. The corneal tissue has extraordinary natural bonding qualities that allow effective healing without the use of stitches. Since only local anesthetic is used, patients remain awake during the procedure. The entire procedure takes only a few minutes.
Improved vision is often possible on the day following the surgery.
Eye drops and night protection are necessary for designated periods of time. That is, the outer layer of the cornea remains in place and the laser removes tissue directly from this outer layer. PRK is used for low to moderate amounts of nearsightedness. The corneal curvature is changed so that the visual images are properly focused on the back of the eye.