角膜水平屈光力不对称对OK镜片定位的影响

目的:通过角膜地形图检查初步探讨角膜塑型术(orthokeratology)中出现镜片偏位的原因。方法:回顾性分析随访≥6个月的OK镜治疗患者84例162眼,平均年龄(15.59±3.29)岁,原始平均等效球镜度(-4.18±1.48)D,平均角膜水平屈光力(43.23±1.30)D。根据患者的屈光度、角膜地形图和试戴情况,选配DK值为58,HDS材料的一副OK镜片,连续夜戴6个月以上。定期给予包括角膜地形图在内的常规眼科检查,数据资料录入电脑,采用SPSS10.0中χ2检验及SAS中的单变量方差分析,分析镜片偏位的原因。结果:对治疗前角膜地形图资料分析发现角膜颞侧与鼻侧的水平屈光力有较明显的不对称,即鼻侧平,颞侧陡,且越向周边相差越明显。治疗6个月后,原角膜前表面屈光力颞侧比鼻侧大的66眼中有38眼出现镜片颞侧偏位(占57.58%),颞侧与鼻侧基本对称的93眼中有17眼出现颞侧偏位(占18.28%),两组比较差异有非常显著性(P<0.001)。而鼻侧比颞侧屈光力大的3眼中有2眼出现镜片鼻侧偏位,因病例数少未列入统计学分析。结论:治疗中镜片易向陡区偏位,角膜前表面的水平屈光力颞侧高于鼻侧的不对称性可能是造成角...

The asymmetry of cornea curvature'' s effect in lens positions in orthokeratology

Objective To discuss the reasons of lens eccentric in orthokeratology (Ortho-K) by topography exam. Methods Eighty-four myopic subjects (162 eyes) had Ortho-k treatment followed- up more than 6 months,aging average of (15.59± 3.29) years,were take a retrospective analysis. Their spherical equivalent refraction averaged of (- 4.18± 1.48)D. All subjects were each fitted with optimal choice of Ortho- K lenses with material of DK 58(HDS) according to their subjective refractions,corneal curvatures and fitting t...