Traumatic Flap Dislocation
Flap dislocation has been reported to occur in up to 1.4% of eyes. Dislocation of the LASIK flap is not uncommon on the first postoperative day, when dryness and adhesion of the flap to the upper tarsal conjunctiva are sufficient to cause the flap to slip. After the first day, however, the reepithelialization of the gutter begins the process of increasing flap stability. Within several weeks, keratocytes begin to lay down new collagen at the cut edge of the Bowman layer, and eventually a fine scar is established at the edge of the flap. However, minimal healing occurs across the stromal interface. Late dislocation from blunt trauma has been reported many years after LASIK. This can occur if the shearing force exceeds the strength of the peripheral Bowman layer–level healing. Flap dislocation requires urgent treatment to replace the flap in its proper anatomical position. The surgeon should make sure that there is no epithelium on the underside of the flap or in the interface, a situation that significantly increases the chances of epithelial ingrowth.
Excerpted from BCSC 2020-2021 series: Section 13 - Refractive Surgery. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.