Sometimes the corneal flap may shift slightly in the first 12 hours after LASIK surgery. This is why it is important, especially during the first few hours, not to rub your eyes and keep them well lubricated. If the flap shifts slightly, wrinkles form, just as wrinkles form in a carpet if you step on it and it isn’t properly nailed down. The medical term for these wrinkles is striae. If striae are present in the center of the cornea, they may blur your vision. Fortunately, striae are easy to fix with a brief, painless procedure if treated early. The flap is lifted and laid back down smoothly, and Dr. Kornmehl places a clear bandage contact lens, that holds the flap securely in place, to wear overnight.
The cornea is covered by a thin, clear skin, called epithelium. This clear skin is made of epithelial cells. When the LASIK flap is lifted and replaced, these cells normally grow back over the top of the flap. About 1% of the time, the cells grow under the flap instead. This condition is called epithelium ingrowth. These cells occasionally caused blurred vision and irritation. Epithelial ingrowth is easy to identify and is treated by gently lifting the flap and clearing away the trapped epithelial cells. Epithelial ingrowth is more common following enhancement procedures when the original flap is relifted.
Regression refers to the tendency of the eye to drift back slightly toward the original refractive error. This occurs more commonly in patients with higher degrees of myopia, hyperopia, or astigmatism. If significant regression occurs, you may require either low-prescription eyeglasses for night driving or an enhancement procedure to “tune up” the original treatment, provided your cornea is thick enough to allow retreatment. Enhancements for regression are usually performed 3-6 months after the original procedure, to allow time for the patient’s vision to stabilize.