Accelerated Corneal Cross-Linking With a Hypoosmolar Riboflavin Solution in Keratoconic Thin Corneas: Short-Term Results

Purpose: The aim of this study was to evaluate the early term topographic and aberration results of accelerated (9 mW/cm(2)) corneal cross-linking (CXL) treatment in keratoconic thin corneas. Methods: Forty-nine eyes from 43 patients (mean age of 21.2 +/- 7.1) with progressive keratoconic thin corneas (<400 mu m without epithelium) who had accelerated corneal CXL with hypoosmolar riboflavin solution throughout the procedure were enrolled. We measured the uncorrected and corrected distance visual acuity, refraction, slit-lamp examination, topographic values, and corneal higher-order aberrations (Pentacam HR, Oculus Optikgerate GmbH) preoperatively and 1, 3, and 6 months after surgery. Results: Before surgery, the corneal thickness was 404 +/- 18 mu m, and the thickness was reduced to 360 +/- 24 mu m after removing the epithelium. After the application of hypoosmolar riboflavin solution, the thickness increased to 432 +/- 44 mu m. At month 6, there was a significant increase in uncorrected distance visual acuity (P = 0.043) and corrected distance visual acuity (P = 0.024), a decrease in spherical refraction (P = 0.041), maximum keratometry (K-max, P = 0.003), anterior elevation values (P = 0.008), corneal thickness (P < 0.001), coma (P = 0.022), spherical aberration (P = 0.001), higher-order root mean square (P = 0.004), and total root mean square (P < 0.001), whereas the cylindrical refraction (P = 0.627), anterior (P = 0.665) and posterior astigmatism (P = 0.165) of the cornea, posterior elevation (P = 0.198), and trefoil (P = 0.141) remained unchanged. No patients showed any complications or scar formation during follow-up. Conclusions: Accelerated corneal CXL with hypoosmolar riboflavin solution throughout the procedure is effective in thin corneas.