A four-year retrospective study of ow and moderate myopia with thin corneas after LASIK refractive surgery center

Objective To investigate the safety and prostecdtive efficacy of LASIK for low and moderate myopia with central corneal thickness below 500 μm.Methods 72 patients 136 eyes received LASIK 4 years ago were enrolled in this study,the range of central corneal thickness preoperatively was 463～498 μm,averaged(484.95±6.65)μm,the range of spherical equivalent was-6.00～-1.50 D,averaged(-3.74±1.27)D.Visual acuity,refractions,Irreg value,central corneal thickness and Diff value of corneal posterior surface were measured at 4 years after surgery.These data were compared with preoperative and early postoperative Results.Results No post-LASIK keratectasia or iatrogenic keratoconus occurred during the 4 years postoperatively,the best corrected visual acuity(BCVA)remained the same with preoperative data,the mean spherical equivalent was(-0.15±0.53)D,122 eyes(89.7%)reached-0.50～+0.50 D,and 8(5.9%)eyes had regression upon 1.00 D.Visual acuity,spherical equivalent,3mm Irreg,5mm Irreg and central corneal thickness had changed after surgery compared with pre-operation,but these changes were not significant at different periods postoperaticely(P0.05);After LASIK,the Diff values of corneal posterior surface had increased with the first 3 months and decreased after that,it was a statistically significant change(P0.05).Conclusion LASIK for low and moderate myopia with thin corneas is proved to have good predictability and stable prostecdtive efficacy.