The wound healing response after laser in situ keratomileusis and photorefractive keratectomy - Elusive control of biological variability and effect on custom laser vision correction

Biological diversity in the wound healing response is thought to be a major factor limiting the predictability of the outcome of refractive surgical p rocedures such as laser in situ keratomileusis and photorefractive keratect omy. Corneal wound healing is critical to the success of topography-linked or wave front-linked excimer laser ablation to optimize visual performance. This is because of the importance of retaining subtle features of custom a blation and the tendency of epithelial hyperplasia and stromal remodeling t o obscure these features following either procedure. The corneal wound heal ing response is exceedingly complex. Keratocyte apoptosis, which occurs in response to epithelial injury, is the earliest observable event in the woun d healing cascades and is therefore an excellent target for pharmacological intervention. Alterations of surgical technique can be designed to limit k eratocyte apoptosis and the subsequent events in corneal wound healing. Abn ormalities of the cascades could contribute to the pathogenesis of corneal diseases. For example, recent data have suggested that perturbation of the keratocyte apoptosis/mitosis balance could underlie the development of kera toconus in a proportion of patients.