MyoRing Implantation with and without Corneal Collagen Crosslinking for the Management of Keratoconus

PURPOSE: To evaluate the safety and efficacy of femtosecond laser-assisted MyoRing implantation with concurrent corneal collagen crosslinking (CXL) compared to MyoRing alone for the treatment of progressive keratoconus. METHODS: A total of 60 patients were enrolled in this randomized controlled trial. The patients were randomly allocated into two groups. In the first group, MyoRing was implanted, while in the second, it was inserted in the corneal stroma using the same technique, along with simultaneous CXL. Visual, refractive, topographic, and abberometric outcomes were measured preoperatively and at every postoperative visit. RESULTS: Data of 47 patients were available at the end of the study; 28 in the MyoRing group and 19 in the MyoRing + CXL group. The mean uncorrected distance visual acuity (UDVA) improved from 0.79 [Formula: see text] 0.39 logMAR to 0.52 [Formula: see text] 0.31 logMAR (P [Formula: see text] 0.05) in the MyoRing + CXL group and from 0.65 [Formula: see text] 0.38 logMAR to 0.62 [Formula: see text] 0.23 logMAR (P = 0.70) in the MyoRing group. CDVA changed from 0.33 [Formula: see text] 0.19 logMAR to 0.25 [Formula: see text] 0.16 logMAR (P = 0.10) in the MyoRing + CXL group and 0.32 [Formula: see text] 0.22 logMAR to 0.33 [Formula: see text] 0.17 logMAR (P [Formula: see text] 0.50) in the MyoRing group. The mean keratometry (Km) decreased from 47.5 [Formula: see text] 2.7 D to 43.8 [Formula: see text] 3.2 D (P [Formula: see text] 0.001) in the MyoRing group and 49.3 [Formula: see text] 3.4 D to 45.1 [Formula: see text] 3.0 D (P [Formula: see text] 0.001) in the MyoRing + CXL group. Besides, horizontal coma was significantly lower in the MyoRing + CXL group (P = 0.022). CONCLUSION: MyoRing insertion combined with CXL is a safe and effective method for the treatment of keratoconus. The visual and topographic outcomes were comparable to that for MyoRing insertion after 10 months; however, horizontal coma was significantly lower in the MyoRing + CXL group.