Zhao Ming-Hui, Wu Qiang, Jia Li-Li, Hu Ping
Department of Ophthalmology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai,, 200233, China.
BMC Ophthalmol. 2015 Jul 29;15:86. doi: 10.1186/s12886-015-0083-2.
Refractive stability is influenced by alterations in corneal curvature and corneal thickness after laser in situ keratomileusis (LASIK). The aim of this study was to analyze the changes of central corneal thickness (CCT) and refractive error following thin-flap LASIK surgery in Chinese eyes.
One hundred and fifty-eight myopic patients (302 eyes) who underwent thin-flap LASIK surgery were prospectively evaluated. CCT was measured by non-contact specular microscopy before, and 1 day, 1 week, and 1, 3, and 6 months following surgery. Age, refractive error, and optic zone diameter were also recorded.
Preoperatively, the mean CCT was 531.6 ± 24.3 μm. At 1 day, 1 week, and 1, 3, and 6 months after surgery, mean CCTs were 431.4 ± 38.4 μm, 422.6 ± 3 7.8 μm, 427.2 ± 38.0 μm, 434.4 ± 38.2 μm, and 435.6 ± 38.0 μm, respectively. Significant changes were detected in CCT values at each time point after thin-flap LASIK treatment (P < 0.05). The mean preoperative spherical equivalent (SE) was -5.73 ± 2.30 diopters (D). At 1 day, 1 week, and 1, 3, and 6 months after surgery, it was 0.26 ± 0.58 D, 0.54 ± 0.52 D, 0.49 ± 0.53 D, 0.45 ± 0.49 D, and 0.37 ± 0.42 D, respectively. The spherical equivalent refraction at 6 months postsurgery was close to the predicted value (0.34 ± 0.30 D). The changes in CCT within 6 months (4.06 ± 9.99 μm) were negatively correlated with age, preoperative refractive error, and optical zone diameter, respectively (r = -0.180, P < 0.05; r = -0.187, P < 0.001; r = -0.171, P < 0.05, respectively). No significant correlation was found between CCT changes and SE changes at different time points, postoperatively.
CCTs decreased significantly at 1 day after surgery, and continued to decline at 1 week after surgery, then increased over time. From postoperative 1 week, SE over time continually shifted to the myopic side.
准分子原位角膜磨镶术（LASIK）后，角膜曲率和角膜厚度的改变会影响屈光稳定性。本研究旨在分析中国人群中薄瓣LASIK手术后中央角膜厚度（CCT）和屈光不正的变化。
前瞻性评估158例接受薄瓣LASIK手术的近视患者（302只眼）。术前、术后1天、1周、1个月、3个月和6个月通过非接触式角膜内皮显微镜测量CCT。记录患者年龄、屈光不正和光学区直径。
术前平均CCT为531.6±24.3μm。术后1天、1周、1个月、3个月和6个月时，平均CCT分别为431.4±38.4μm、422.6±37.8μm、427.2±38.0μm、434.4±38.2μm和435.6±38.0μm。薄瓣LASIK治疗后各时间点CCT值均有显著变化（P<0.05）。术前平均球镜等效度（SE）为-5.73±2.30屈光度（D）。术后1天、1周、1个月、3个月和6个月时，分别为0.26±0.58D、0.54±0.52D、0.49±0.53D、0.45±0.49D和0.37±0.42D。术后6个月时球镜等效屈光接近预测值（0.34±0.30D）。6个月内CCT的变化（4.06±9.99μm）分别与年龄、术前屈光不正和光学区直径呈负相关（r=-0.180，P<0.05；r=-0.187，P<0.001；r=-0.171，P<0.05）。术后不同时间点CCT变化与SE变化之间未发现显著相关性。
术后1天CCT显著下降，术后1周继续下降，随后随时间增加。术后1周起，SE随时间不断向近视侧偏移。
