Corneal Allogenic Intrastromal Ring Segments (CAIRS) Combined With Corneal Cross-linking for Keratoconus

PURPOSE: To describe a new technique for the treatment of keratoconus using corneal allogenic intrastromal ring segments (CAIRS)., METHODS: CAIRS trephined from donor cornea using a double-bladed trephine were implanted into mid-depth femtosecond laser-dissected channels in the cornea of patients with keratoconus in the 6.5-mm optic zone, followed by accelerated corneal cross-linking (A-CXL)-either conventional or contact lens-assisted CXL (A-CACXL), depending on minimum corneal thickness, RESULTS: Twenty patients (24 eyes) with stage 1 to 4 keratoconus (Amslar-Krumeich grading) were included. Mean follow-up was 11.58 +/- 3.6 months (range: 6 to 18 months). There was significant improvement in uncorrected (2.79 <= 2.65 lines; range: 0 to 8 lines) and corrected (1.29 <= 1.33 lines: range: 0 to 5 lines) distance visual acuity, spherical equivalent, simulated maximum keratomatry, steepest keratometiy, topographic astigmatism, anterior and posterior best fit spheres, and mean power in the 3- and 5-mm zones. No eye showed progression during the entire follow-up. All segments remained well positioned and no segment-induced complications were seen. No other major intraoperative or postoperative complications were observed, CONCLUSIONS: This pilot study indicates that CAIRS with CXL may be a simple, safe, and effective option for treating keratoconus. Further studies are recommended to determine long-term outcomes.