Estabilidade do Tratamento de Queratocone Combinado com Crosslinking Associado a Queratectomia Fotorrefrativa com Laser Excimer

Abstract

Introduction: The purpose of this study is to evaluate the stability of crosslinking (CXL) treatment associated with photorefractive keratectomy (PRK) with excimer laser in patients with keratoconus, through comparison of keratometric and topographic parameters and functional results at 6 months postoperatively and at the last evaluation. Methods: Seventy-four eyes of 71 patients with established kerotoconus who had contact lens intolerance and/or disease progression were included. The eyes were submitted to CXL plus partial PRK and a residual stromal thickness of 325 μm in the end of the laser procedure was required. We compared uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), refractive sphere and cylinder, keratometric parameters (K1, K2, Kmax, average K) and minimum pachymetry at 6 months and at last evaluation. Results: The mean age was 32.12±9.73 years. We report the results at 6 months and last evaluation (occurred between 12 and 37 months postoperatively), mean 17.09±6.39 months. All parameters (K1, K2, average K, maximum K, K1 axis, spherical equivalent and minimum pachymetry) remained stable, except for BCVA which improved 0.05 logMAR (p<0.05). No patient lost more than two lines of Snellen chart and the greatest improvement was five lines. Conclusion: Our results suggest that accelerated CXL with topography-guided PRK in keratoconic eyes resulted in progressive BCVA improvement between 6 months and 12 to 37 months postoperatively. Keratometric and topographic values remained stable postoperatively, confirming the efficacy of the procedure in arresting progression of keratoconus.