Abstract:AIM:To analyze the changes of central corneal thickness (CCT) and refractive error in post thin-flap laser in situ keratomileusis (LASIK) eyes. METHODS:Totally 158 myopic patients (302 eyes) having thin-flap LASIK were prospectively evaluated. CCT and refractive error were measured before and 1 day, 1 week, 1 month, 3, 6 months after surgery. Age, predicted photoablation depth, optic zone ,postoperative predicted diopter and actual diopter changes were also recorded. RESULTS:Preoperatively, the mean CCT was 531.6±24.3μm. On the first day postoperatively, CCT rapidly decreased. At 1 month, it was 427.2±38.0μm. At 3 months, it was 434.4±38.2μm, and at 6 months, it was 435.6±38.0μm. The CCT difference before and 1 day after LASIK was highly correlated with predicted photoablation depth(r=0.916, P<0.01). The increase of corneal thickness in post LASIK eyes in 6 months was negatively correlated with age, preoperative refractive error, and optical zone, respectively (r=-0.180, P=0.026; r=-0.187, P<0.01; r= -0.171, P=0.137, respectively). The spherical equivalent refraction at 6 months was close to the preoperative predicted values. All patients were followed up for six months, no case of refractive regression occurred.At 6 months, all the uncorrected visual acuity was≥0.8, the average visual acuity was 1.3±0.2. CONCLUSION:At 6 months after surgery, CCT and spherical equivalent refraction were relatively stable. The increase of CCT in post thin-flap LASIK eyes in 6 months was negatively correlated with age, preoperative refractive error, and optical zone, respectively. The spherical equivalent refraction at 6 months was close to the preoperational predicted values. The treatment of myopia in thin-flap LASIK has a good accuracy, and a long-term prediction.