Long-term Outcomes of Accelerated Corneal Cross-linking in the Treatment of Keratoconus: Comparison of Hypotonic Riboflavin Solution With Standard Riboflavin Solution

PURPOSE: To determine 2-year efficacy of accelerated corneal cross-linking (CXL) in keratoconus treatment using standard riboflavin-dextran or hypotonic riboflavin solutions. METHODS: Patients undergoing accelerated CXL (epithelium-off 10 minutes, 9 mW/cm(2) protocol) with standard riboflavin solution (48 eyes of 48 patients) or hypotonic riboflavin solution (43 eyes of 43 patients) were included and followed up for 2 years. Thinnest corneal thickness (TCT), maximum keratometry, and visual acuity were measured and changes from baseline to postoperative 6, 12, and 24 months were compared between the two groups. RESULTS: The preoperative mean TCT with intact epithelium was 472.0 +/- 23.9 and 427.5 +/- 22.3 mu m in the standard riboflavin and hypotonic riboflavin groups, respectively (P < .001). The decreases in the mean TCT values from baseline to postoperative 6 months were similar between the standard riboflavin (from 472 to 436 mu m) and hypotonic riboflavin (from 427 to 394 mu m) groups. This suggested that the hypotonic riboflavin solution was comparable with the standard riboflavin solution in preserving corneal. thickness in keratoconus. There were no significant differences between the study groups regarding the postoperative changes in maximum keratometry or visual acuity. CONCLUSIONS: The efficacy of accelerated CXL with hypotonic riboflavin solution was comparable to that with the standard riboflavin solution in reducing keratoconus progression in a 2-year follow-up period.