Long-term Results of Corneal Cross-linking for Recurrence of Keratoconus After Keratoplasty

PURPOSE: To evaluate the long-term efficacy of accelerated corneal cross-linking (A-CXL) in halting the progression of recurrence of keratoconus in the graft. METHODS: This was a retrospective chart review of patients who underwent A-CXL for recurrence of keratoconus between January 2017 and December 2018. Results of eye evaluations performed up to 4 years after A-CXL included slit-lamp examination, corneal tomography and biomechanics, binocular corrected distance visual acuity (CDVA), and the manifest refraction equivalent sphere. The efficacy of A-CXL was assessed with reference to thinnest corneal thickness (TCT), mean anterior axial radius curvature in corneal periphery (ARC), and posterior axial radius curvature (PRC) tomography data indicating the stability of the ectasia. RESULTS: Data from 25 eyes were collected. Significant worsening in TCT, ARC, PCR, maximum keratometry, posterior eccentricity, and CDVA (P =.01) were found before A-CXL. At 4 years of follow-up, no changes in all tomographic parameters and significant improvement in CDVA (P =.02) and in corneal biomechanics (stiffness parameter A1, deformation amplitude ratio highest, inverse concave radius, and applanation 2 velocity; P =.01) were found. None of the included eyes developed postoperative complications or required regrafting or refractive procedures. CONCLUSIONS: A-CXL is a safe procedure that could play a role in preventing graft ectatic changes in patients with recurrence of keratoconus after keratoplasty, strengthening the graft and halting the natural progression of the ectasia, with positive effects in improving CDVA.