Photorefractive intrastromal corneal crosslinking for treatment of myopic refractive error: Findings from 12-month prospective study using an epithelium-off protocol

Purpose: To assess the long-term effectiveness and safety of photorefractive intrastromal corneal crosslinking (CXL) in patients with low myopia. Setting: Ruhr University Eye Hospital, Bochum, Germany. Design: Prospective case series. Methods: Healthy eyes with myopia were treated with photo refractive intrastromal CXL using the Mosaic System. Riboflavin 0.1% solution (VibeX Rapid) was topically administered, followed by 365 nm ultraviolet-A (30 mW/cm(2)) irradiance. Efficacy was assessed by the uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent (MRSE), and keratometry. Safety was assessed by corrected distance visual acuity (CDVA), slitlamp biomicroscopy, endothelial cell count, and adverse event rates. Results: Fourteen patients (24 eyes) with a mean age of 35.7 years were included. At all follow-ups, a statistically significant improvement in UDVA was observed (all P < .001). The CDVA progressively improved from 1 month postoperatively and a statistically significant improvement was achieved at 12 months (P < .001). The average reduction in manifest sphere was 0.90 diopter (D) +/- 0.40 (SD) by 12 months. There were no significant differences in mean manifest sphere and MRSE at 3, 6, or 12 months. Compared with baseline, significant reductions in comeal curvature were also observed at all follow-ups (all P < .05). There were no significant changes in endothelial cell density (P = 1.00) or number of cells (P = .95) at 12 months postoperatively, and no adverse events were reported. Conclusion: Photorefractive intrastromal CXL was a safe and efficacious treatment of refractive error in patients with low myopia.