角膜塑形镜配戴矫治低中高度近视的临床疗效观察

Clinical observation of orthokeratology on low, moderate and high myopia

目的探讨夜戴型角膜塑形镜矫正青少年低、中、高度近视的临床疗效及引起各组治疗效果差异的影响因素。方法青少年近视患者68例(136只眼),平均年龄(10.2±2.6)岁,按照等效球镜度分为3组,低度近视组(-1.00^-3.00)D:70只眼;中度近视组(-3.25^-6.00)D:51只眼;高度近视组(-6.25^-8.50)D:15只眼。观察戴镜前及戴镜1年后3组的裸眼视力、等效球镜度、前房深度、眼轴、中央及旁中央3 mm和5 mm角膜前后表面曲率。结果戴镜1年后,3组等效球镜度均有降低,各组内及组间差异,有统计学意义(均P<0.05),随着基线等效球镜度数的增高,戴镜1年后等效球镜度数降低越明显;3组眼轴组内增长差异,无统计学意义(均P>0.05),低度近视眼轴增长值明显高于中、高度组,差异有统计学意义(P=0.035,0.006);三组角膜前表面中央及旁中央3 mm和5 mm Kf、Ks均明显变平坦(均P<0.05),且越往周边曲率变化越小,差异有统计学意义(均P<0.05),中、高度组较低度近视组,角膜前表面各区域曲率变化更明显(均P<0.05)。角膜后表面中央及旁中央3 mm和5 mm的Kf、Ks值治疗前后组内及组间差异,无统计学意义(均P>0.05)。结论角膜塑形镜在控制近视发展中效果明确,且对中高度近视控制效果明显,角膜塑形镜主要通过改变角膜前表面曲率,减少周边视网膜远视性离焦,能有效延缓近视的发展及眼轴的增长。

OBJECTIVE To study the clinical effect and its related factors of overnight or-thokeratology on low,moderate and high myopia in teenagers.METHODS Sixty-eight subjects(136 eyes,aged 10.2±2.6 years)were included and were divided into three groups according to spherical equivalent refraction(SER):low myopia group(-1.00^-3.00)D with 70 eyes,moderate myopia group(-3.25^-6.00)D with 51 eyes,high myopia group(-6.25^-8.50)D with 15 eyes.Vision(logMAR),SER,anterior chamber depth,axial length,the curvature of orthopedic area(the front and rear surface of central area as well as 3 mm,5 mm away from central areas)were measured at baseline and after 1 year wearing orthokeratology.RESULTS After 1 year treatment,the visual acuities of all groups increased significantly and SER reduced obviously(P<0.05).High SER in baseline received more significant decrease after one-year intervention.There were no significant differences in the changes of axial length in all groups(P>0.05).But the increase in axial length of low myopia group was more obvious than counterparts in moderate and high myopia group(P=0.035,0.006).After treatment the corneal curvatures in all groups all decreased significantly(P<0.05),and the closer to the peripheral area the smaller changes were(P<0.05).The variation of Kf,Ks value of central area,and areas that 3mm,5mm away from it in corneal posterior surface in moderate and high myopia were more significantly than it in low myopia group(P<0.05).There was no statistical significance in comparative difference among Kf,Ks value of central area,and areas that 3 mm,5 mm away from it in corneal posterior surface(P>0.05).CONCLUSIONS Overnight orthokeratology was effective in management of myopia,especially in moderate and high myopia.The possible mechanism was that it affected the front surface of the cornea,alleviated hyperopic defocus of peripheral retina,slowed the development of myopia and inhibited axial elongation.