Comparative Results Between “Epi-Off” Accelerated and “Epi-Off” Standard Corneal Collagen Crosslinking-UVA in Progressive Keratoconus – 7 Years of Follow-Up

Abstract

Cristina Ariadna Nicula,1,2 Anca Maria Rednik,3 Ariadna Patricia Nicula,4 Adriana Elena Bulboaca,5 Dorin Nicula,2 Karin Ursula Horvath6 1Department of Ophthalmology, Medicine and Pharmacy University “Iuliu Hațieganu”, Cluj-Napoca, Romania; 2Oculens Clinic, Cluj-Napoca, Romania; 3Eye County Hospital, Department of Ophthalmology, Cluj-Napoca, Romania; 4Eye County Hospital, Department of Ophthalmology, Arad, Romania; 5Department of Pathophysiology, Medicine and Pharmacy University “Iuliu Hațieganu”, Cluj Napoca, Romania; 6Department of Ophthalmology, Medicine and Pharmacy Science and Technology University “George Emil Palade”, Târgu Mureș, RomaniaCorrespondence: Cristina Ariadna NiculaDepartment of Ophthalmology, Medicine and Pharmacy University “Iuliu Hațieganu”, Cluj-Napoca, RomaniaTel +011 40-722849575Email [email protected]: The purpose of the present study was to assess the long-term efficiency and safety of the “epi-off” accelerated CXL (9 mW/cm2 for 10 minutes) in comparison to the standard “epi-off” CXL (3 mW/cm2 for 30 minutes) in terms of topographical and keratometric parameters, refractive data and visual outcomes at 7 years of follow-up, in progressive keratoconus.Material and Method: A retrospective and comparative study was performed. A total of 183 eyes from 183 patients with documented progressive keratoconus were included in the study. The patients were divided in two groups: 93 eyes from 93 patients underwent “epi-off” standard cross-linking technique (3 mW/cm2 for 30 minutes) (S-CXL group) and 90 eyes from 90 patients underwent accelerated “epi-off” corneal CXL technique (9 mW/cm2 for 10 minutes) (A-CXL group).Results: Improvements in uncorrected distance visual acuity (UDVA) were statistically significant compared to baseline values in both groups at each time-point visit (p=0.0421 at 1 year, p=0.0411 at 7 years for A-CXL and p=0.0375 at 1 year, p=0.0389 at 7 years for S-CXL). At 7 years there was a statistically significant increase in CDVA (p=0.039 in the A-CXL group and p=0.0343 in the S-CXL group at 7 years). Statistically significant reduction was noticed in Ksteep (p=0.0411 in A-CXL group and p=0.0224 in S-CXL group), Kflat (p=0.0198 in A-CXL group and p=0.008 in S-CXL group), K mean (p=0.0106 in A-CXL group and p=0.0193 in S-CXL group) and Kmax (p=0.0413 in A-CXL group and p=0.054 in S-CXL group) at 7 years, compared to baseline values, in both groups, but without any statistically difference between the two procedures, at all time-point visits (p> 0.05).Conclusion: The long-term outcomes of “epi-off” accelerated corneal collagen crosslinking-UVA (9 mW/cm2 for 10 minutes) are similar to standard “epi-off” corneal collagen crosslinking procedure in the treatment of progressive keratoconus.Keywords: progression, keratoconus, accelerated cross-linking, standard cross-linking

Keywords

• progression
• keratoconus
• accelerated cross-linking
• standard cross-linking