Rouse M W, Hyman L, Hussein M, Solan H
Southern California College of Optometry, Fullerton, USA.
Optom Vis Sci. 1998 Feb;75(2):88-96. doi: 10.1097/00006324-199802000-00012.
To estimate the frequency of convergence insufficiency (Cl) and its related characteristics among 8- to 12-year-old children randomly selected from 2 optometry clinic populations.
Clinic records of 620 children were randomly selected and reviewed according to a standard protocol, using a systematic sampling method based on the total number of 8- to 12-year-old children seen over a 1-year period at 2 optometry clinics. Records were reviewed for demographic and clinical data. Data on Cl-related symptoms were obtained at one of the sites. Records that met the eligibility criteria of: good visual acuity (20/30 or better in both eyes); minimal refractive error (-0.50 to +1.00 D and < or = 1.00 D of astigmatism in either eye, and < or = 1.00 D of anisometropia); and no strabismus were evaluated for Cl-related characteristics. Eligible children were classified according to the direction of their near heterophoria and the number of the following clinical signs present: (1) exophoria at near > or = 4 delta than at far; (2) insufficient fusional convergence [i.e., failing Sheard's criterion or minimum normative positive fusional vergence (PFV) of 12 delta base-out (BO) blur/15 delta BO break]; and (3) receded nearpoint of convergence (NPC) of > or = 7.5 cm break or > or = 10.5 cm recovery. Children were then classified as: no Cl (nonexophoric at near or < 4 delta difference between far and near); low suspect (exophoric at near and 1 sign); high suspect (exophoric at near and 2 signs); or definite Cl (exophoric at near and 3 signs).
Sixty-seven percent (415/620) of the records met the eligibility criteria and had complete data on phoria, NPC, and PFV. The age (mean +/- SD) of the study population was 10.2 +/- 1.2 years. Ethnicity data were available for 85% of those eligible; the ethnic distribution was 36% African American, 29% Caucasian, 19% Hispanic, and 1% Asian. About one-half of the 415 children were classified as either low suspect (33%); high suspect (12%); or definite Cl (6%). Clinically significant Cl (high suspect and definite categories) was identified in 17.6% of the children. The percentage of children rated as symptomatic increased with the number of Cl-related clinical signs present.
These findings suggest a high frequency of Cl in optometry clinic populations and a potential correlation between patient symptoms and the number of Cl signs present.
评估从两家验光诊所人群中随机选取的8至12岁儿童集合不足（CI）的发生率及其相关特征。
采用系统抽样方法，根据两家验光诊所1年内接诊的8至12岁儿童总数，随机选取620名儿童的临床记录并按照标准方案进行审查。审查记录中的人口统计学和临床数据。在其中一个地点获取与CI相关症状的数据。符合以下入选标准的记录：视力良好（双眼视力均为20/30或更好）；屈光不正最小（任何一只眼睛的球镜度数为-0.50至+1.00 D且散光度数≤1.00 D，屈光参差≤1.00 D）；无斜视，对其CI相关特征进行评估。符合条件的儿童根据其近隐斜方向以及出现的以下临床体征数量进行分类：（1）近眼外隐斜比远眼外隐斜大≥4棱镜度；（2）融合性集合不足[即未达到谢尔德准则或最小标准正融合性聚散（PFV）为12棱镜度底向外（BO）模糊/15棱镜度BO破裂]；（3）集合近点后移（NPC）破裂≥7.5 cm或恢复≥10.5 cm。然后将儿童分类为：无CI（近眼无外隐斜或远近眼外隐斜差异<4棱镜度）；低度可疑（近眼外隐斜且有1个体征）；高度可疑（近眼外隐斜且有2个体征）；或确诊CI（近眼外隐斜且有3个体征）。
67%（415/620）的记录符合入选标准，并且有关于隐斜、NPC和PFV的完整数据。研究人群的年龄（均值±标准差）为10.2±1.2岁。85%符合条件的儿童有族裔数据；族裔分布为36%非裔美国人、29%白种人、19%西班牙裔和1%亚洲人。415名儿童中约一半被分类为低度可疑（33%）、高度可疑（12%）或确诊CI（6%）。17.6%的儿童被确定有临床显著CI（高度可疑和确诊类别）。被评定有症状的儿童百分比随着出现的CI相关临床体征数量增加而升高。
这些发现表明验光诊所人群中CI的发生率较高，并且患者症状与出现的CI体征数量之间可能存在相关性。
