Lea Symbols视力表与ETDRS视力表在学龄前儿童视力筛查中的应用比较

Comparative analysis of Lea Symbols chart and ETDRS chart in Chinese preschool children's vision examination

目的比较LeaSymbols视力表与ETDRS视力表在中国学龄前儿童视力筛查中的检查配合程度、视力值及双眼间视力差异.方法采用前瞻性自身对照研究设计,对泉州市泉港区实验幼儿园的241名42~78个月的学龄前儿童进行全面的眼科检查,平均月龄为(61.9±10.3)个月,其中屈光度数在正常范围的学龄前儿童132名.使用LeaSymbols视力表和ETDRS视力表测量左、右眼的单眼远视力,采用LogMAR记录法记录视力值.结果LeaSymbols视力表和ETDRS视力表在42~78个月儿童中的检查配合程度分别为96.7%(466/482)和95.0%(458/482),2种视力表的检查配合程度比较,差异无统计学意义(χ2=1.669,P>0.05).2种视力表测得的LogMAR视力值呈明显正相关(rs=0.726,P<0.001),2种视力表测量一致性较好(Kappa=0.531).在132名屈光正常儿童中,LeaSymbols视力表测得的视力水平比ETDRS视力表高0.0312LogMAR,差异有统计学意义(W=-7.461,P<0.001),2种视力表的测量一致性较好(Kappa=0.467);2种视力表在测量双眼间视力差异方面,差异无统计学意义(W=-0.889,P=0.374);LeaSymbols视力表和ETDRS视力表中男童视力水平均好于女童,差异均有统计学意义(U=-3.352、-4.679,均P<0.001);LeaSymbols视力表和ETDRS视力表测得的LogMAR视力值与月龄均呈负相关(rs=-0.423、-0.437,P<0.001);各不同年龄段组中LeaSymbols视力表测得的LogMAR视力水平均较ETDRS视力表测得的视力水平好,差异均有统计学意义(均P<0.001).结论LeaSymbols视力表和ETDRS视力表在42~78个月学龄前儿童中的检查配合程度较高,可用于42个月及以上儿童的视力检查.LeaSymbols视力表测得的视力水平较ETDRS视力表高.在学龄前儿童视力筛查中,应注意几种视力表检查的差异,谨慎判断视力异常.

Objective To compare cooperation degree and visual acuity difference between Lea Symbols chart and ETDRS chart in Chinese preschool children. Methods A prospective self-control study design was performed.Two hundred and forty-one children aged from 42 months to 78 months in Quanzhou Quangang Experimental Kindergarten were enrolled and the mean age was (61.9±10.3) months.Among them, 132 pre-school children had normal refractive index.All children completed comprehensive ophthalmological examinations and measurement of monocular visual acuity using Lea Symbols chart and ETDRS chart.All monocular visual acuity scores were recorded in LogMAR form.This study followed the Declaration of Helsinki and this study protocol was approved by Medical Ethics Committee of The Second Affiliated Hospital of Fujian Medical University (No.2017[62]). Written informed consent was obtained from all guardians before entering the study. Results The cooperation degrees of Lea Symbols chart and ETDRS chart were 96.7% and 95.0% in 42-78 months of children, respectively, with no significant difference between the two visual acuity tables (χ2=1.669, P>0.05). The visual acuity measured by Lea Symbols chart was positively correlated with that measured by ETDRS chart (rs=0.726, P<0.001). The measurement consistency of the two chart was good (Kappa=0.531). Among 132 normal refractive children, the visual acuity level measured by Lea Symbols chart was higher than that measured by ETDRS chart (W=-7.461, P<0.001);the measurement consistency of the two visual acuity chart was good (Kappa=0.467). There was no significant difference between the two charts in measuring the binocular vision difference (W=-0.889, P=0.374);the visual acuity levels of boys measured by Lea Symbols chart and ETDRS chart were higher than those of girls, and the difference was statistically significant (U=-3.352,-4.679;both at P<0.001);the visual acuity values measured by Lea Symbols chart and ETDRS chart were negatively correlated with age (rs=-0.423,-0.437;both at P<0.001);the visual acuity measured by Lea Symbols chart was higher than that measured by ETDRS chart in different age groups, and the differences were statistically significant (all at P<0.001). Conclusions The measurement of visual acuity by Lea Symbols chart and ETDRS chart can be achieved with a high cooperation degree in 42 months and older children.The visual acuity measured by Lea Symbols chart is higher than that measured by ETDRS chart.In the preschool children's vision screening, we should pay attention to the difference between the two kinds of visual charts, and be careful to judge the abnormal vision.