Combined cross-linking with femtosecond laser myoring implantation versus combined cross-linking with femtosecond laser keraring implantation in the treatment of keratoconus

Abstract

Purpose The aim of this study was to compare the results as regards efficacy, safety, and patient satisfaction between two combined procedures. The first is combined femtosecond laser myoring implantation with cross-linking (CXL) and the second is combined femtosecond laser keraring implantation with CXL for the treatment of keratoconus. Setting The study was conducted in Sohag University Hospital, Sohag University, Egypt. Design This was a prospective nonrandomized clinical comparative study. Patients and methods A total of 46 eyes of 30 patients with keratoconus were included in this study. Group A included 27 eyes of 17 patients that were subjected to combined cross-linking with femtosecond laser myoring implantation, whereas group B included 19 eyes of 13 patients that were subjected to combined cross-linking with femtosecond laser keraring implantation. All eyes were subjected to preoperative and postoperative uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), manifest refraction, slit-lamp examination of the anterior segment, intraocular pressure, fundus examination, and keratometry and pachymetry assessed with Pentacam corneal topographies at 3 and 6 months of follow-up period. Results In group A, the preoperative mean UCVA was 1.30 ± 0.28 (logMAR ± SD), whereas the postoperative mean UCVA was 0.90 ± 0.12. The preoperative mean BCVA was 0.70 ± 0.23, whereas the postoperative mean BCVA was 0.30 ± 0.17. The preoperative K average was 53.27 ± 0.62 (D ± SD), whereas the postoperative K average was 45.83 ± 0.64. The postoperative astigmatic correction was 1.51 ± 0.42 (D ± SD). In group B, the preoperative mean UCVA was 1.30 ± 0.33, whereas the postoperative mean UCVA was 1 ± 0.16. The preoperative mean BCVA was 0.90 ± 0.46, whereas the postoperative mean BCVA was 0.60 ± 0.32. The preoperative K average was 50.97 ± 0.48, whereas the postoperative K average was 49.01 ± 0.32. The postoperative astigmatic correction was 3.07 ± 0.15. Conclusion This study proved that combined CXL with myoring implantation is effective in the correction of the myopic component of keratoconus. Combined CXL with keraring implantation is effective in the correction of the astigmatic component in keratoconus. The type and the site of keratoconus cone together with the K readings can help in the preoperative decision as to which type of ring is best in each keratoconus case. This study proved that there is a synergistic action when CXL is combined with intracorneal rings (myoring of keraring).