儿童眼轴与角膜曲率在单纯性近视初期的变化

Variable Changes of Axial Length and Corneal Radius in Early - StageMyopic Children

目的探讨青春期前儿童的正视眼与初期单纯性近视眼之间,眼轴长度、角膜曲率及其相关关系的变化。 方法随机选取我科屈光门诊的轻度近视患儿30例(60眼),散瞳验光,测量眼轴长度、角膜曲率与角膜屈光力,并与同期随机选取的30例(60眼)健康正视眼儿童相比较。 结果近视眼组平均眼轴长度为(24.02±0.77)mm,正视眼组为(22.99±0.72)mm,两组眼轴差异非常显著(P<0.01)。两组角膜曲率、角膜屈光力之间差异无显著性。以水平向角膜曲率测得眼轴长度与角膜曲率的比值(AL/CR),近视眼组为3.032±0.058,正视眼组为2.899±0.095,差异非常显著(P<0.01)。 结论青春期前,儿童在由正视跟转化为轻度近视跟的过程中,以眼轴增长为主,表现为轴性近视。AL/CR超过3是近视发生的高危指标。

Objective To study the variable changes of axial length , corneal radius and their relationship in emmetropic and early -stage myopic children. Methods Thirty mild myopic children and 30 emmetropic children were selected randomly. Refraction was measured with cycloplegic retinoscopy. Axial length, corneal radius and refraction power of cornea were measured with a keratometer and A - scan ul-trasonography. Results The mean axial length was significantly increased in the myopic group. It was (24. 02±0. 77) mm while it was (22.99±0.72) mm in the emmetropic group(P <0. 01) . Corneal radius and refraction power were of no significant difference in two groups. The axial length/corneal radius ratio was significantly different between two groups (P < 0. 01 ) . Conclusion Axial length increases in the progress from emmetropia to mild myopia. The AL/CR ratio >3 appears to be a risk factor for the onset of myopia.