Transepithelial versus epithelium-off crosslinking in adults with progressive keratoconus

Abstract

To compare the efficacy of epithelium-off corneal collagen crosslinking (CXL) with transepithelial CXL in patients with progressive keratoconus. Department of Ophthalmology, Marmara University School of Medicine, Istanbul, Turkey. Retrospective cohort study. Eyes that had transepithelial CXL were compared with eyes treated with epithelium-off CXL. All patients with a follow-up of 18 months were evaluated for uncorrected (UDVA) and corrected (CDVA) distance visual acuities, corneal topography, aberrometry, and pachymetry (Pentacam). The mean patient age was 22.8 years ± 4.7 (SD) (range 18 to 31 years) in the transepithelial group (30 eyes) and 23.7 ± 3.9 years (range 18 to 30 years) in the epithelium-off group (30 eyes). The mean UDVA and CDVA significantly improved in both groups (P < .001). There was no significant difference in the CDVA gain between the 2 groups. In the epithelium-off group, significant improvements occurred in spherical error (P = .002), spherical equivalent (P = .004), maximum keratometry (K), flat K (P = .036), and steep K (P < .001). The reductions in flat K, steep K, and maximum K were greater in the epithelium-off group (P = .004 for flat K; P < .001 for steep K and maximum K). In the transepithelial group, significant improvements occurred in the cylindrical error (P = .009) and in the index of surface variance and index of surface asymmetry (both P < .001). Although transepithelial CXL seemed to have reduced effectiveness in inducing improvement in topographic indices, its effect on visual acuity is likely to be similar to that of epithelium-off CXL. No author has a financial or proprietary interest in any material or method mentioned.