Abstract
Abstract: :
Purpose:To investigate and to compare visual and refractive outcome after wavefront-guided laser in virgin and re-enhanced corneas to correct myopia and astigmatism. Methods:In a prospective, comparative study between the Zyoptix customized ablation to correct myopic LASIK and the Zyoptix Ablation Re-enhancement (ZAR) for Lasik re-enhancement. 38 eyes were included in this study, 20 eyes were virgin myopic eyes eligible for Zyoptix, the other 18 eyes were suffering from residual myopia after standard Lasik and they were re-enhanced using the wavefront-guided laser after lefting the flap. LASIK was performed using the Hansatome microkeratome (Hansatome, Chiron Vision, Irvine, California, USA) and Chiron Technolas 217-Z (Bausch & Lomb, Irvine, California, USA). Data measured included visual outcome, ocular wavefront aberration measurements, contrast sensitivity, refraction, pachymetry and keratometry were performed preoperatively 24 hours, 1 week, 1 month and 3 months after surgery. Results:The numerically calculated higher-order optical aberrations correlated with the clinical and visual results, demonstrating a significantly major decrease in coma and spherical-like aberration after ZAR technique comparatively to ZYOPTIX resuls. Conclusion:ZAR technique is a step forward procedure to minimize higher-order aberrations and to correct residual myopia and astigmatism after primary Lasik. It is not possible to correct both higher order and sphero-cylindrical aberration because of the aberration induced by microkeratome cut and the sphero-cylindrical ablation.
Keywords: 549 refractive surgery: other technologies • 550 refractive surgery: optical quality • 544 refractive surgery