Long-term results of corneal collagen crosslinking for progressive keratoconus

Abstract Purpose To evaluate long-term keratoconus stability after corneal crosslinking (CXL) with riboflavin. Methods In this prospective study, 57 eyes of 55 patients with progressive keratoconus, consecutively treated with ultraviolet A (UVA) – riboflavin CXL, were examined with the corneal topographer Pentacam, the biometer IOLMaster and the analyzer of corneal biomechanics Ocular Response Analyzer before and during a 24 months follow-up after CXL. Results Twenty-four months after CXL, there was a significant improvement in best corrected visual acuity (BCVA) ( P K max), and corneal volume (CV) ( P P  = 0.01). No significant changes in anterior chamber volume (ACV) and depth (ACD), ( P  = 0.8), corneal hysteresis (CH) ( P  = 0.16) and corneal resistance factor (CRF) ( P  = 0.06) were found. However, in the subgroup of patients with decreased K max readings 24 months after treatment, both CH and CRF showed a significant reduction ( P Conclusion In the first month after the procedure, CXL induces a reduction in corneal volume. During the 24 months follow-up the cornea tends to recover its original volume with a persistence of the CXL efficacy.