Transepithelial Corneal Crosslinking Using a Novel Ultraviolet Light-Emitting Contact Lens Device: A Pilot Study

Purpose: To evaluate the feasibility of a novel, on-eye UVA light-emitting contact lens device driven by fiber optics for the corneal crosslinking (CXL) of patients with keratoconus. Methods: In nine corneal transplant candidates with advanced keratoconus a scleral contact lens reservoir containing 0.007% benzalkonium chloride preserved with 0.25% riboflavin-monophosphate was placed on the eye for 30 minutes. The reservoir lens was removed and replaced with the CXLens UVA light-emitting contact lens. A 375-nm UVA light at 4 mW/cm(2) intensity was delivered for 30 minutes for a dose of 7.2 J/cm(2). A one-sided paired t-test was used to evaluate mean differences in maximum keratometry, thinnest corneal thickness, and endothelial cell density between screening and 6 months after CXL. A two-sided paired t-test was used to evaluate differences in best-corrected distance visual acuity between screening and 6 months after CXL. Results: All patients received the treatment as per protocol and adhered to follow-up testing. At 6 months after CXL, treated eyes had an average -1.0 +/- 1.6 diopters decrease in the maximum keratometry (P = 0.049), a nonsignificant 2.3 +/- 7.5 letter improvement in best-corrected distance visual acuity (P = 0.19), a nonsignificant -17 +/- 14 mu m decrease in thinnest corneal thickness (P < 0.01), and a nonsignificant -86 +/- 266 cells/mm(2) decrease in endothelial cell density (P = 0.20). Conclusions: Our pilot study demonstrated the feasibility of the novel CXL device for the treatment of keratoconus and indicates the device is ready for larger scale studies with longer follow-up periods.