الفهرس | Only 14 pages are availabe for public view |
Abstract Novel technologies in laser in situ keratomileusis by new surgical instrumentation has been developed, making the surgical procedure easier for the surgeon with better excimer laser ablation algorithms, increasing the optical quality of the ablation and thus the safety of the vision correction procedure. New techniques have been obtained that can be classified into two categories: Wavefront optimized and Wavefront guided algorithms. The Wavefront optimized approach considers an eye’s refractive error and preoperative keratometry, in conjunction with the variable ablation depths of peripherally delivered laser pulses, to apply a precalculated aspheric ablation that aims to limit induced SAs and maintaining the original Q value of the cornea. The Wavefront guided approach renders a customized treatment plan based on an eye’s unique preoperative aberrometry with the intent of not only minimizing induced postoperative aberrations but also reducing or eliminating preoperative HOA. Many advances in LASIK ablation profiles have been developed over conventional ones: Q value adjusted and TG (TG). Aim of work to compare between Q value based ablation and Topography-guided LASIK as regards safety, visual acuity, contrast sensitivity and high order aberration HOAs. |