ارزيابي ميزان تاثير ثبات ايمني و قابليت پيش بيني ليزيك در اصلاح نزديك

Evaluation of Efficacy, stability, safety and predictability of LASIK in correcting of myopia and myopic astigmatism

Background and Objectives: Evaluation of efficacy, safety, stability and predictability of LASIK in myopia and myopic astigmatism with determining the changes in refraction, topography, pachymetry and visual acuity. Materials and Methods: In a Semiexperimental Clinical Traial study from 2001-2003, 80 eyes of 41 patients treated for myopia and myopic astigmatism with Nidek EC-5000 excimer laser. In this study refraction, visual acuity, phachymetry and topography befor and after LASIK are compared and changes of them are analyzed with Ttest, wilcoxon and Bartlett tests. Results: Mean age of patients was 30±10 years and Mean duration of follow was 12 months. Mean value of BCVA befor LASIK was 0.1 logMar 20/23. Mean value of UCVA after LASIK in the last visit was 0.2 LogMar 20.23 and BCVA was 0.35 LogMar 20/22 Safty index was 1.01 and efficacy index was 0.93. Mean spherical equivalent okf refractive error in the spectacle plane befor LASIK was - 5.75±3(SD) and in the last visit after LASIK reduced to 0.33±0.62D. Mean value of corrected refractive error in 80 eyes was 5.69D. Mean amount amount of corneal thickness befor LASIK was 539±46(SD) micron that reduced to 473±49 microm post operatively. Mean amount of total ablation in LASIK was 81.40 micron with 14.31 micron for ID of correction. Mean amount of corneal effective power befor LASIK was 43.83±1.63 D that was reduced to 39.47±1.84 5days after surgery and to 38.97±2.05D in the last visit. Therfore there was no regression in this study. Conclusion: LASIK is an effective procedure to correcting myopia and myopic astigmatism and has desiable safety, stability and predictability.