Guo, X., Fu, M., Ding, X., Morgan, I.G., Zeng, Y., He, M.
小屈 眼科 深圳
摘要：目的：旨在记录一组中国学龄前儿童眼生物测量学分布，评估其与屈光状态的关系。设计：基于人口的横断面研究。研究对象：共有来自8所代表性幼儿园的1133名3至6岁的学龄前儿童。方法：睫状肌麻痹前采用部分相干激光干涉仪（IOL Master，德国Oberkochen，Carl Zeiss Meditec公司）获得包括眼轴长度（AL），前房深度（ACD）和角膜曲率半径（CR）。计算晶体度数（LP）和AL-CR率。使用自动矫正器（KR8800;日本东京拓普康公司（Topcon Corp.，Tokyo，Japan））测量睫状肌麻痹屈光度（3滴1％环戊酯），并计算等效球镜（SER）。评估生物特征和屈光参数，如年龄和性别。主要观察指标：眼部生物测量分布及其与屈光度的关系。结果：1127名成功散瞳验光的儿童（99.5％）平均SER为1.37±0.63屈光度（d）。近视患病率从3岁时的0％上升到6岁时的3.7％（95％可信区间，1.0％-6.5％）。生物统计学参数遵循高斯分布，AL为22.39±0.68mm，CR为7.79±0.25mm，LP为24.61±1.42D;和非高斯分布，ACD为3.34±0.24mm，AL-to-CR比值为2.88±0.06。 ACD和AL-CR比从3岁增加到6岁，CR维持稳定，而LP下降。总的来说，SER略有下降。对于SER方差， AL分别为18.6％和AL-CR比例为39.8％，而校正年龄和性别后AL，CR和LP为80.0％。结论：中国青少年以轻度远视为主， 6岁以下近视率低。 AL增加1mm仅与0.45D的近视变化有关。 LP下降减少了通常与AL增加相关的近视变化，并在这个年龄组屈光发展中发挥关键作用。
PURPOSE:To document the distribution of ocular biometry and to evaluate its associations with refraction in a group of Chinese preschoolers.DESIGN:Population-based cross-sectional study.PARTICIPANTS:A total of 1133 preschoolers 3 to 6 years of age from 8 representative kindergartens.METHODS:Biometric measurements including axial length (AL), anterior chamber depth (ACD), and corneal radius of curvature (CR) were obtained from partial-coherence laser interferometry (IOL Master; Carl Zeiss Meditec, Oberkochen, Germany) before cycloplegia. Lens power (LP) and AL-to-CR ratio were calculated. Cycloplegic refraction (3 drops of 1% cyclopentolate) was measured using an autorefractor (KR8800; Topcon Corp., Tokyo, Japan), and spherical equivalent refraction (SER) was calculated. Biometric and refractive parameters were assessed as a function of age and gender. Multiple regression analysis was performed to explore the associations between refraction and ocular biometry.MAIN OUTCOME MEASURES:Ocular biometric distributions and their relationships to refraction.RESULTS:Among the 1127 children (99.5%) with successful cycloplegic refraction, mean SER was 1.37±0.63 diopters (D). Prevalence of myopia increased from 0% at 3 years of age to 3.7% (95% confidence interval, 1.0%-6.5%) at 6 years of age. Biometric parameters followed Gaussian distributions with means of 22.39±0.68 mm for AL, 7.79±0.25 mm for CR, and 24.61±1.42 D for calculated LP; and non-Gaussian distributions with means of 3.34±0.24 mm for ACD and 2.88±0.06 for AL-to-CR ratio. Axial length, ACD, and AL-to-CR ratio increased from 3 to 6 years of age, CR remained stable, whereas LP declined. Overall, SER declined slightly. For the SER variance, AL explained 18.6% and AL-to-CR ratio explained 39.8%, whereas AL, CR, and LP accounted for 80.0% after adjusting for age and gender.CONCLUSIONS:Young Chinese children are predominantly mildly hyperopic, with a low prevalence of myopia by the age of 6 years. An increase of 1 mm in AL was associated with only 0.45 D of myopic change. Decreases in LP reduce the myopic shifts that normally would be associated with increases in AL, and thus play a key role in refractive development in this age group.