U.S. Multicenter Clinical Trial of Corneal Collagen Crosslinking for Treatment of Corneal Ectasia after Refractive Surgery

Purpose To evaluate the safety and efficacy of corneal collagen crosslinking (CXL) for the treatment of corneal ectasia after laser refractive surgery. Design Prospective, randomized, multicenter, controlled clinical trial. Participants One hundred seventy-nine subjects with corneal ectasia after previous refractive surgery. Methods The treatment group underwent standard CXL, and the sham control group received riboflavin alone without removal of the epithelium. Main Outcome Measures The primary efficacy criterion was the change over 1 year of topography-derived maximum keratometry (K), comparing treatment with control groups. Secondary outcomes evaluated were corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent, endothelial cell count, and adverse events. Results In the crosslinking treatment group, the maximum K value decreased by 0.7 diopters (D) from baseline to 1 year, whereas there was continued progression in the control group (1.3 D difference between treatment and control, P Conclusions Corneal collagen crosslinking was effective in improving the maximum K value, CDVA, and UDVA in eyes with corneal ectasia 1 year after treatment, with an excellent safety profile. CXL is the first approved procedure to diminish progression of this ectatic corneal process.