Clinical Results of Repeated Corneal Collagen Cross-linking in Progressive Keratoconus.

Abstract

To evaluate the effectiveness of repeated corneal collagen cross-linking (CXL) in eyes with progressive keratoconus after primary CXL. Twelve eyes of 10 patients who underwent repeated CXL were included in this study. All cases were treated with a second CXL when disease progression was noted. Uncorrected visual acuity, best-corrected distance visual acuity, and corneal tomography were performed before and after repeated CXL. Common risk factors for progression were recorded. The mean age of the patients was 23.4 ± 6.2 (14-34) years. Eye rubbing was detected in 6 patients. The preoperative maximum keratometry (Kmax) value was >58.0 diopters (D) in 11 eyes (62.2 ± 4.9 D). Repeated CXL was performed with a mean interval of 19.3 months after the first CXL procedure when a disease progression of 2.3 D on average in Kmax was determined. With a mean follow-up of 36 months, Kmax regressed in 8 eyes, remained stable in 2 eyes, and progressed in 2 eyes after repeated CXL. Uncorrected and corrected visual acuity remained unchanged. No complications were observed. Repeated CXL seems to be effective in stabilizing keratoconus progression after failure of primary CXL. Patients should be followed up at least for 2 years after primary CXL.