Effective corneal collagen crosslinking in advanced cases of progressive keratoconus

PURPOSE: To evaluate the 1-year results of corneal collagen crosslinking (CXL) in mild to moderate cases and advanced cases of progressive keratoconus. SETTING: Department of Ophthalmology, University Medical Center Utrecht, the Netherlands. DESIGN: Retrospective cohort study. METHODS: Eyes with progressive keratoconus had CXL between January 2010 and April 2011. Patients were divided into 2 subgroups as follows: Group 1, mild to moderate keratoconus with a preoperative maximum keratometry (K) of less than 58.0 diopters (D), and Group 2, advanced keratoconus with a maximum K of 58.0 D or more. Visual acuity, refraction, and elevation-based topography were evaluated at baseline and 12 months after CXL. RESULTS: The study comprised 53 eyes of 42 patients. In the overall group, progression was halted in 48 eyes (91%). The CXL-induced corneal flattening occurred in 11 (42%) of 26 eyes in Group 1 and 20 (74%) of 27 eyes in Group 2. Five of 7 keratoconus indices improved 12 months after CXL. The failure rate was comparable in the subgroups (3 eyes in Group 1, 2 eyes in Group 2). No major complications occurred in either subgroup. CONCLUSIONS: Stabilization after CXL was achieved in mild to moderate cases and advanced cases of progressive keratoconus. The amount of failure was comparable in the 2 subgroups. The CXL-induced flattening was more pronounced in the advanced subgroup.