PHOTOREFRACTIVE KERATECTOMY FOLLOWED BY CROSS-LINKING VS CROSS-LINKING ALONE FOR MANAGEMENT OF PROGRESSIVE KERATOCONUS:2-YEAR FOLLOW-UP

PURPOSE: To compare visual, refractive, topographic, and corneal higher-order aberration outcome at the 2-year follow-up after customized photorefractive keratectomy (PRK) followed by cross-linking (CXL) as a single procedure versus CXL alone in eyes with progressive keratoconus. DESIGN: Prospective, interventional, nonrandomized clinical trial. METHODS: Seventeen patients (34 eyes) with progressive keratoconus were assigned to 2 groups: the worse eye (17 eyes) was assigned to the PRK plus CXL group and the better eye (17 fellow eyes) was assigned to the CXL group. RESULTS: In the PRK plus CXL group, uncorrected distance acuity improved significantly, from a mean ± standard deviation of 0.63 ± 0.36 logarithm of the minimal angle of resolution (logMAR) units to 0.19 ± 0.17 logMAR units (P < .05) and best distance acuity from 0.06 ± 0.08 logMAR to 0.03 ± 0.06 logMAR (P < .05). Manifest refraction spherical equivalent and spherical and cylindrical power improved significantly (P < .05). Simulated keratometry, flattest, steepest, average, cylindrical, apex keratometry, and inferior-superior value decreased significantly (P < .05). Total and coma-like aberrations significantly decreased for all pupil diameters (P < .05). In the CXL group, uncorrected distance acuity improved, but not significantly, from 0.59 ± 0.29 logMAR units to 0.52 ± 0.29 logMAR units, and best distance acuity improved from 0.06 ± 0.11 logMAR units to 0.04 ± 0.07 logMAR units (P > .05). Manifest refraction spherical equivalent and cylindrical power improvement was not significant (P > .05), unlike spherical power (P < .05). Steepest simulated keratometry, average simulated keratometry, and inferior-superior value significantly decreased (P < .05), unlike flattest simulated keratometry, cylindrical simulated keratometry, and apex keratometry (P > .05). Total and coma-like aberrations were not decreased significantly for all pupil diameters (P > .05). No significant endothelial changes were observed in either group. CONCLUSIONS: The PRK plus CXL procedure may be a good option to reduce corneal aberrations and stabilize corneas with progressive keratoconus.