Abstract
Abstract: :
Purpose: To evaluate the clinical safety and efficacy of riboflavin/UVA induced collagen crosslinking for stabilizing the progression of keratoconus. Design: Prospective, non–randomized clinical pilot study. Methods: 27 eyes of 22 patients with mod to advanced keratoconus were included. After central corneal abrasion, photosensitizing riboflavin drops were applied the eyes were exposed to UVA(370 nm, 3 mW/cm2) in a 2 cm distance for 30 minutes. Post operative examinations were performed in the 6 month intervals, including visual acuity testing, corneal topography, slit–lamp examination, endothelial cell count density, elasticity testing with a contact ultrasonic device, and clinical photographic documentation. Results: In all treated eyes, the progression of of keratoconus appeared to stabilize. In 12 eyes regression with a reduction of maximal keratometry readings by 3.01 D and of the refractive error by 2.14 D was found. Corneal and lens transparency, ECC and IOP were unchanged. Cornea elasticity measurements changed from an average 1.9 (1.6 to 2.5) pre–op to 1.2 (0.8 to 1.8) post–op. Visual acuity was slightly improved in 15 eyes (65%). Conclusions: Collagen crosslinking may offer promise in the stabilization of progression of keratoconus by reducing cornea elasticity. This stability may enable excimer refractive surgery correction, which has been traditionally contra–indicated. Long term results are necessary to evaluate the duration of the stiffening effect and exclude long term side effects. Supported by Research to Prevent Blindness
Keywords: cornea: stroma and keratocytes • anterior segment • refractive surgery