中文摘要：

目的 分析我国河南安阳初中学生的眼屈光度和眼轴长度等眼生物参数的分布.方法 随机整群抽样.以学校为单位在河南安阳城区随机抽取4所初中,从初一开始对学生进行详细眼部检查和问卷调查,每年进行随访.从2011年9至12月完成了初一学生调查,从2013年9至12月完成了同一样本初三学生的调查.研究遵守赫尔辛基宣言,获得了首都医科大学附属北京同仁医院伦理委员会批准,所有参与研究学生的监护人均签署了书面同意书.采用1％环戊通和美多丽散瞳,电脑验光获得屈光度值并计算等效球镜度,近视定义为等效球镜≤-0.5D,远视定义为等效球镜≥＋0.5D,正视定义为等效球镜在-0.5D和0.5D之间.非接触光学测量仪Lenstar LS900获取眼轴长度、角膜曲率和前房深度等.仅纳入右眼数据进行分析.结果 基线共纳入2 267名初一学生,随访获得1 839名初三学生的有效数据,应答率为81.1％.初三学生的平均年龄为（14.7±0.5）岁,男性占48.4％,屈光度呈偏态分布,平均值为（-2.62 ±2.19）D.近视、高度近视、正视和远视的患病率分别为82.7％、7.1％、9.8％和7.5％.近视和高度近视两年累积发病率分别为47.1％和4.5％.眼轴长度、前房深度、角膜平坦和陡峭曲率均呈正态分布,分别为（24.8±1.1） mm、（3.18±0.25） mm、（42.8±1.4）D和（43.9±1.6）D.男生比女生眼轴更长（P=0.000）,前房更深（P=0.000）,角膜则相对平坦（P=0.000）.眼轴长度及前房深度与屈光度有明显相关性.结论 我国河南安阳初中学生群体表现为低度近视状态,近视患病率和发病率均较高,高度近视日益增多,亟需加强对青少年近视防控的研究.

英文摘要：

Objective To investigate the distribution of spherical equivalent and ocular biometric parameters in a population of grade 7 children in central China.Methods 2 363 grade 7 students of junior high schools were randomly sampled.The students have been examined at baseline and followed up annually.Detailed questionairies and most of the ocular examinations were performed.Spherical equivalent （Seq） was calculated as sphere ＋ 1/2 cylinder from cycloplegic autorefraction.Myopia was defined as spherical equivalent ≤-0.5D,hyperopia as spherical equivalent ≥ ＋ 0.5D and emmetropia between -0.5 D and ＋ 0.5 D.The Lensar LS900 was used to measure corneal curvatures,axial length and anterior chamber depth.Right eyes results were analyzed.Results Among 2 267 children who have the baseline examination,1 839 children participated the follow up examination（response rate,81.1%）,with an mean age of 14.7 years （range,12.9-17.6） and male ratio of 48.4%.The mean spherical equivalent refraction was （-2.62 ± 2.19）D.The prevalence rates of myopia,high myopia,emmetropia and hyperopia were 82.7%,7.1%,9.8% and 7.5%.The cumulative incidence rates of myopia and high myopia were 47.1% and 4.5% respectively.Axial length,anterior chamber depth,and corneal curvature were normally distributed.The mean axial length,anterior chamber depth,and corneal curvature were （24.8 ± 1.1） mm,（3.18 ± 0.25） mm,（42.8 ± 1.4） D and （43.9 ± 1.6） D respectively.Axial length was longer,anterior chamber depth was deeper,and corneal were flatter in the male （P =0.000）.Axial length and anterior chamber depth correlated negatively with refraction.Conclusions A moderate myopic distribution of refraction was present in the grade 9 students in central China.The prevalence rates of myopia and high myopia were relatively high in this 14-year-old population compared to other countries.It is necessary to strengthen the prevention of juvenile myopia.