目的：观察和分析角膜塑形镜治疗后角膜形态的变化，评估角膜塑形镜治疗后光学区偏离中心对控制近视的影响。

方法：回顾性临床研究。对134例134眼近视患儿配戴角膜塑形镜矫治近视，平均年龄10.66±1.79岁， 均取右眼数据进行研究。分别在戴镜前及戴镜后3、6、12、18、24mo检查视力、眼轴和角膜地形图。使用SPSS19.0进行统计学分析。

结果：戴镜后3、6、12、18、24mo的光学区偏瞳孔中心距离分别为0.84±0.45、0.77±0.40、0.79±0.41、0.78±0.41、0.79±0.42mm，差异无统计学意义(F=1.187，P=0.319)。戴镜24mo后平均光学区偏中心距离为0.79±0.35mm，眼轴增长均值为0.32±0.30mm。戴镜24mo后平均偏中心距离轻度(<0.5mm)、中度(0.5～1.0mm)、重度(>1.0mm)的眼轴增长分别为0.45±0.34、0.32±0.28、0.23±0.29mm，差异有统计学意义(F=3.825，P=0.024)。戴镜后的平均偏中心距离和眼轴增长经线性回归分析，其线性关系有统计学意义(F=7.246，P=0.008)，线性回归方程Y=0.478-0.194X。戴镜24mo后，18眼有重影，其偏中心距离均值1.18±0.36mm； 116眼无重影，其偏中心距离均值0.73±0.31mm，偏中心距离比较差异有统计学意义(t=5.59，P<0.01)。

结论：光学区偏中心距离在角膜塑形镜治疗3mo后趋于稳定，且对控制近视的效果和视觉质量有影响。

METHODS: This was a retrospective clinical study. One hundred and thirty-four children(134 eyes)with myopia aged 10.66±1.79 years were treated with overnight orthokeratology lenses. The examinations of visual acuity, axial length and corneal topography were performed before and 3, 6, 12, 18 and 24mo after wearing orthokeratology. The results of right eye were taken as the object of this study, SPSS19.0 for statistical analysis.

RESULTS: The distance of decentration about 134 children at 3, 6, 12, 18 and 24mo after wearing orthokeratology were 0.84±0.45mm, 0.77±0.40mm, 0.79±0.41mm, 0.78±0.41mm, and 0.79±0.42mm respectively. The difference between these groups were not statistically significant(F=1.187,P=0.319). The mean distance of decentration after orthokeratology treatment was 0.79±0.35mm, the growth of axial length after 24mo was 0.32±0.30mm, the mean distance of decentration divided into 3 groups, mild(<0.5mm)27 eyes, medium(0.5-1.0mm)79 eyes, severe(>1.0mm)28 eyes, the growth of axial length frow 3 groups after 24mo were 0.45±0.34mm, 0.32±0.28mm, 0.23±0.29mm, were statistically significant difference between each groups(F=3.825, P=0.024). By linear-regression analysis, the growth of axial length and the mean distance of decentration after 24mo was statistically significant difference(F=7.246, P=0.008), equation of linear regression was Y=0.478-0.194X. At 24mo after wearing orthokeratology, the mean distance of decentration about 18 eyes with monocular diplopia was 1.18±0.36mm, and 116 eyes without monocular was 0.73±0.31mm, the distance of decentration were statistically significant difference(t=5.59, P<0.01).

CONCLUSION: The degree of decentration tended to be stable after 3mo of orthokeratology treatment and influenced the effect of myopia control and visual quality.