Determination of efficacy of repeated CXL and probable risk factors in patients with progressive keratoconus

Int Ophthalmol. 2023 Sep;43(9):3157-3164. doi: 10.1007/s10792-023-02715-0. Epub 2023 May 17.

Abstract

Purpose: To evaluate the efficacy of Repeated CXL (Re-CXL) and determine probable risk factors that lead to Re-CXL in patients with progressive keratoconus.

Method: In this retrospective study, the medical records of patients who had been re-operated in our center between 2014 to 2020 due to progressive keratoconus were evaluated; seven eyes of seven patients had undergone Re-CXL procedure. Pre- and post-treatment variables were recorded and analyzed using IBM SPSS Statistics software.

Results: The mean interval between the 1st and 2nd CXL was 49.71 months (range 12-72 months). Out of 7 patients for whom Re-CXL was considered necessary, eye rubbing was detected in 6 patients. Six patients were very young with a mean age of 13 years at primary CXL and 16.83 years at Re-CXL. Visual acuity and astigmatism did not change significantly after the Re-CXL procedure (p-values = 0.18, 0.91, respectively). When measurements of these indices prior to Re-CXL and post Re-CXL were compared, K1 (p-value = 0.01), K2 (p-value = 0.01), Kmean (p-value = 0.01), and Kmax (p-value = 0.008) changed significantly. As to pachymetry (p-value = 0.46), it did not change significantly. Kmax value regressed in all eyes after Re-CXL.

Conclusion: Re-CXL procedure was effective in halting the progression of disease. As to the risk factors, eye rubbed-related mechanism like eye rubbing and VKC, lower age, and pre-operative Kmax value > 58 D are the risk factors of Re-CXL procedure.

Keywords: Keratoconus; Patients; Repeated CXL; Risk Factors.

MeSH terms

  • Adolescent
  • Collagen / therapeutic use
  • Corneal Pachymetry
  • Corneal Stroma
  • Corneal Topography / methods
  • Cross-Linking Reagents / therapeutic use
  • Follow-Up Studies
  • Humans
  • Keratoconus* / diagnosis
  • Keratoconus* / drug therapy
  • Photochemotherapy* / methods
  • Photosensitizing Agents / therapeutic use
  • Retrospective Studies
  • Riboflavin / therapeutic use
  • Risk Factors
  • Ultraviolet Rays

Substances

  • Photosensitizing Agents
  • Riboflavin
  • Collagen
  • Cross-Linking Reagents