Myoring and Ferrara ring segment implantation using femtosecond laser for treatment of keratoconus

Abstract

Purpose To compare visual acuity, refraction, and topographic corneal changes after implantation of a MyoRing versus Ferrara ring segment for management of keratoconus. Patients and methods This is a prospective nonrandomized clinical comparative study. Forty eyes of 25 patients with keratoconus grades 2–4 were included in the study and were divided into two groups: group A (MyoRing group) included 20 eyes of patients with keratoconus subjected to femtosecond laser-assisted MyoRing implantation and group B included 20 eyes of patients with keratoconus subjected to femtosecond laser-assisted Ferrara ring segment implantation. Results Forty eyes of 25 patients (12 males and 13 females) with keratoconus grades 2–4 were enrolled in this study. The mean age of the patients in group A was 26.62±6.18 years and in group B was 24.72±5.06 years. The mean central corneal thickness improved from 440.25 to 476.57 µm in group A and from 441.35 to 470.63 μm in group B. The mean keratometric (K) reading decreased from 49.97±14.26 to 44.55±2.16 D in group A and from 48.69+4.26 to 44.85±1.92 D in group B. There was a statistically significant improvement in the postoperative uncorrected distance visual acuity, corrected distance visual acuity, K readings, manifest spherical and cylindrical refractive errors, and spherical equivalent in both groups. No serious intraoperative complications were reported. Conclusion Both MyoRing and Ferrara ring segments are effective modalities for treatment of grades 2–4 keratoconus, but MyoRing had a superior capability in improving the keratoconus parameters as well as in halting the progression of the disease.