配戴角膜塑形镜后偏心对人眼高阶像差的动态影响

目的观察分析配戴角膜塑形镜后角膜光学压平区偏中心状态及不同瞳孔直径下人眼高阶像差的动态变化，探索偏心性质和程度对视觉的影响。方法前瞻性临床研究。30例年龄为（23．6-2．3）岁的中低度近视患者配戴夜戴型角膜塑形镜，等效球镜度为-0．75—．4．00D，平均（-2．61±0．83）D。在戴镜前和戴镜后1周、1个月、3个月分别检测角膜地形图，检测波前像差（在自然瞳孔下检查，分别提取3mm和6mm瞳孔直径下的全眼高阶像差结果），并通过分析戴镜后的角膜地形图形态，测量出角膜塑形镜压平区中心相对于瞳孔中心的偏心量（包括偏心距离和角度），只取右眼数据进行研究。采用Pearson相关性分析、重复测量资料方差分析对数据进行分析。结果配戴角膜塑形镜后1周、1个月、3个月时的平均偏心距离分别为（0．53±0．26）mm、（0．54±0．32）mm和（0．60±0．35）mm，偏心的方向主要集中于颞上方，偏心距离和角度在戴后3个时间点之间差异无统计学意义：戴后各时间点，偏心距离与戴前等效球镜度、初始散光量均不相关。在3mm与6mm瞳孔直径下，总高阶像差、总三阶像差、总四阶像差、总彗差（包括垂直彗差和水平彗差）、总三叶草和球差均方根值在戴后1周、1个月、3个月时均比戴前有明显增加，但各项像差在戴后各时间点之间差异均无统计学意义：在戴后的各个时间点，6mm瞳孔直径的像差结果都较3mm时大。戴后不同瞳孑L直径下，垂直或水平偏心距离与相应方向彗差在戴后各时间点均呈正相关；而总偏心距离与总高阶像差、总三阶像差、总四阶像差、总彗差、总三叶草和球差在戴后各时间点均不相关。结论配戴角膜塑形镜后偏心客观存在，程度较小并在1周后稳定；术后偏心会造成人眼高阶像差显著增加。

The dynamic influence of induced decentered orthokeratology lenses on higher-order wavefront aberrations

Objective To evaluate the status of orthokeratology decentration and dynamic changes in higher-order aberrations with different pupil diameters and to discuss its effect on visual quality. Methods This was a prospective clinical study. Thirty myopic subjects （30 right eyes） were fitted with overnight orthokeratology lenses. The mean age was 23.6-2.3 years and the initial mean spherical equivalent （SE） refractive error was -2.61：d）.83 D. All subjects underwent corneal topography measurements and wavefront aberration measurements before orthokeratology and 1 week, 1 month and 3 months after orthokeratology. The decentration （distance and angle） of the center of the flattened corneal area after orthokeratology was calculated relative to the pupil center. The higher-order aberrations under 3 mm and 6 mm pupil diameters were evaluated. Data were analyzed using pearson correlation, repeated measured ANOVA. Results The decentrations at 1 week, 1 month, and 3 months after orthokeratototy were 0.53±0.26 mm, 0.54±0.32 mm and 0.60±0.35 mm, respectivdy. The decentration was mainly located in the superior temporal quadrant. There were no statistically significant differences in the decentration measurements at different timepoints after orthokeratology. The location and magnitude of decentration had no correlation with initial SE or astigmatism. Total higher-order aberrations, third order, fourth order, combined coma, and spherical-like aberrations under 3 mm and 6 mm pupil diameters significantly increased after orthokeratology treatment （P〈0.05）.However, there were no statistically significant differences in wavefront aberrations at different timepoints after orthokeratology. The aberrations under a 6 mm pupil diameter had increased significantly compared to a 3 mm pupil diameter （P〈0.05） after orthokeratology treatment. The magnitude of decentration in the horizontal or vertical direction was positively correlated with the coma in the corresponding direction. However, no correlations were found between the total magnitude of decentration and other higher-order aberrations. Conclusion The decentration from orthokertology present throughout the entire process, but it is very subtle and became stable after 1 week. Decentration increase higher-order aberrations.