Fine wrinkles (called microstriae) in the corneal flap are another common complication of LASIK surgery. Most microstriae do not cause vision problems and don’t require treatment. In other cases, however, your LASIK surgeon may feel the wrinkles may affect vision or corneal healing, and will take measures to reduce or eliminate them.
Your risk for microstriae increases if you have a very high amount of nearsightedness prior to LASIK. This is because the laser has to reshape your cornea to a greater extent, making the curvature of the treated corneal "bed" significantly flatter than the curvature of the back surface of the corneal flap.
In some cases, the surgeon can reduce microstriae after LASIK by massaging the corneal flap a blunt surgical tool. In other cases, it's necessary to lift the flap and reposition it to reduce or eliminate microstriae.
For more information, see LASIK complications.