The objective of this randomized study is to investigate the difference between two regimens of transepithelial crosslinking. The study will compare two riboflavin dosing regimens during the crosslinking procedure. The primary objective of this study is to evaluate the safety and efficacy of transepithelial corneal collagen crosslinking performed with two different riboflavin administration protocols during the UVA portion of the procedure. Safety and efficacy outcomes will then be compared between the treatment groups. In particular, the two groups will be compared with regard to their efficacy in reducing corneal curvature. Secondary outcomes will include visual acuity. Safety assessments will include a tabulation of adverse events, patient symptoms, loss of visual acuity, changes in endothelial cell density, and slit lamp examination.
Corneal collagen crosslinking (CXL) has been demonstrated as an effective method of reducing progression of both keratoconus and corneal ectasia after surgery, as well as possibly decreasing the steepness of the cornea in these pathologies. Transepithelial crosslinking in which the epithelium is not removed has been proposed to offer a number of advantages over traditional crosslinking including an increased safety profile by reducing the risk for infection and scarring, faster visual recovery and improved patient comfort in the early postoperative healing period.