Corneal collagen cross-linking in the treatment of progressive keratoconus-preliminary results

Abstract

To evaluate the efficacy and safety of riboflavin-ultraviolet-A (UV-A)-induced corneal collagen cross-linking (CXL) in the management of progressive keratoconus. It was a retrospective case series study. Twenty-three eyes of 13 patients with progressive keratoconus were included. Corneal collagen crosslinking was performed under topical anesthesia including corneal de-epithelization (8 mm diameter) and instillation of 0.1% riboflavin (in 20% dextran T500 solution) every 3 minutes for a total of 30 minutes. The irradiation is performed for another 30 min using a solid-state UV-A illuminator at 370 nm and an irradiance of 3 mW/cm(2). Average follow-up was 15.23 ± 3.39 months (range: 12 to 22 months). Visual acuity, corneal topography, in vivo confocal microscopy, and endothelial cell count were evaluated at baseline and at 1, 3, 6, and 12 months follow-up. Mean uncorrected visual acuity(UCVA) and best spectacle-corrected visual acuity (BSCVA) increased 0.115 ± 0.158 LogMAR (t = 3.418, P = 0.0026) and 0.114 ± 0.218 LogMAR (t = 2.441, P = 0.0236) 12 months postoperatively respectively. Interim analysis of treated eyes showed a flattening of the steepest simulated keratometry value (K-max) and astigmatism by an average of (1.893 ± 3.713) diopters (D) (t = 2.391, P = 0.0262) and (0.117 ± 1.488) D (t = 0.370, P = 0.715) respectively at 12 months. Central corneal thickness decreased by (27.5 ± 26.8) µm (t = 4.812, P = 0.000) and (1.54 ± 19.4) µm ( t = 0.147, P = 0.885) at one month and 12 months postoperatively respectively.Intraocular pressure, endothelial cell count, lens and fundus didn't change significantly at 12 months follow-up. CXL stabilised and improved the UCVA and BSCVA as well as the maximum k-readings at 1 year postoperatively in our cohort. It seems to be a safe and promising procedure to stop the progression of keratoconus.