Of the 1.4 million refractive surgeries performed each year using laser assisted in situ keratomileusis (LASIK) in the U.S., 1 in 2500 will result in post-LASIK ectasia-a thinning and bulging of the cornea analogous to keratoconus that becomes evident months or years after the LASIK procedure. Studies of patients who developed post-LASIK ectasia have led to a risk stratification system that uses preoperative information to evaluate the risk of developing post-LASIK ectasia. Approximately 1/3 of patients satisfy the conditions that correlate with developing post-LASIK ectasia. If a treatment were available with sufficiently low cost, low risk and high efficacy, patients in the """"""""at risk"""""""" group might be treated prophylactically to greatly reduce the probability of subsequent ectasia. Some cases of post-LASIK ectasia occur in patients who have preoperative profiles that would not be identified as """"""""at risk;"""""""" therefore, a safe and effective means to arrest the progression of ectasia as soon as it is identified is also needed. Corneal crosslinking using the riboflavin/UVA protocol pioneered by Wollensak, Seiler, and Spoerl, has shown promise in halting the progress of post-LASIK ectasia, providing a potential treatment to postpone or avoid corneal transpantation necessitated by the ectasia. However, the treatment is costly (requiring a surgeon to perform the 35 minute procedure), painful (requiring that the cornea be debrided) and toxic (the treatment kills all cells in the anterior 300 Post-laser in situ keratomileusis (LASIK) ectasia is a serious complication of refractive corneal procedures resulting in progressive steepening and thinning of the cornea that can lead to severe visual loss and require corneal transplantation. This project will result in an innovative light-activated treatment that will arrest post-LASIK ectasia for those who already developed it and will serve as a preventative measure for others who are receiving the refractive correction procedure.Public Health Relevance
