CXL for Treatment of Corneal Ectasia After Refractive Surgery
Ophthalmology, October 2017
Corneal ectasia remains one of the most visually significant complications of excimer laser surgery. Hersh et al. demonstrated that collagen cross-linking (CXL), which can stabilize corneal architecture in patients with keratoconus, also is effective and safe for managing corneal ectasia after refractive surgery.
The authors conducted 2 clinical trials concurrently at 11 sites, enrolling 179 patients with ectasia after refractive surgery (mean age, 43 years). Patients were assigned randomly to receive standard ultraviolet A–riboflavin 0.1% CXL (n = 91 eyes) or sham treatment (riboflavin alone, no removal of epithelium; n = 88 eyes). Efficacy was assessed by examining between-group differences in maximum K change from baseline (preoperative state) to 1 year postoperatively. A difference of ≥ 1 D was considered clinically significant. Secondary endpoints included corrected and uncorrected distance visual acuity (DVA) and adverse events.
The CXL group had a significant decrease in mean maximum K value from baseline to 12 months postoperatively (0.7 ± 2.1 D; p < .05), whereas the sham control group had a significant increase (0.6 ± 2.1 D; p < .05). The between-group difference was 1.3 D (p < .0001). Of the 76 CXL-treated eyes for which 12-month maximum K data were available, 14 eyes decreased ≥ 2 D and 3 eyes increased ≥ 2 D. Mean corrected DVA improved by 5 logMAR letters in the CXL group; 23 eyes gained ≥ 10 logMAR letters and 3 eyes lost ≥ 10 letters. Among the latter 3 eyes, there was no obvious clinical cause for the decline. Uncorrected DVA improved by 4.6 letters with CXL treatment. The most common adverse effect of CXL was corneal haze, which persisted in 5 eyes at 1 year.
The authors concluded that CXL generally reduces the progression of corneal ectasia and appears to have an excellent safety profile. Variability in the results suggest that careful patient selection may optimize outcomes.
The original article can be found here.