Huang Yang-Qing, Huang He, Huang Rong-Zhi
Biomedical Engineering Institute of Xi'an Jiaotong University, Xi'an 710049, Shaanxi Province, China.
Yijishan Hospital of Wannan Medical College, Wuhu 241001, Anhui Province, China.
Int J Ophthalmol. 2014 Jun 18;7(3):457-62. doi: 10.3980/j.issn.2222-3959.2014.03.13. eCollection 2014.
To introduce a new near-vision chart for children aged 3-5 years old and its clinical applications.
The new near-vision chart which combined the Bailey-Lovie layout with a newly devised set of symmetry symbols was designed based on Weber-Fechner law. It consists of 15 rows of symmetry symbols, corresponding to a visual acuity range from 1.3 to 0.1 logMAR. The optotypes were red against a white background and were specially shaped four basic geometric symbols: circle, square, triangle, and cross, which matched the preschool children's cognitive level. A regular geometric progression of the optotype sizes and distribution was employed to arrange in 15 lines. The progression rate of the optotype size between two lines was 1.2589 and two smaller groups of optotypes ranging from 0.7 to -0.1 logMAR were included for repetitive testing. A near visual acuity was recorded in logMAR or decimal, and the testing distance was 25 cm.
This new near-vision chart with pediatric acuity test optotypes which consists of 4 different symbols (triangle, square, cross, and circle) met the national and international eye chart design guidelines. When performing the near visual acuity assessment in preschoolers (3-5 years old). It overcame an inability to recognize the letters of the alphabet and difficulties in designating the direction of black abstract symbols such as the tumbling 'E' or Landolt 'C', which the subjects were prone to lose interest in. Near vision may be recorded in different notations: decimal acuity and logMAR. These two notations can be easily converted each other in the new near-vision chart. The measurements of this new chart not only showed a significant correlation and a good consistency with the Chinese national standard logarithmic near-vision chart (r=0.932, P<0.01), but also indicated good test-retest reliability (89% of retest scores were within 0.1 logMAR units of the initial test score) and a high response rate.
The results of this study support the validity and reliability of near visual acuity measurements using the new near-vision chart in children aged 3-5y over a wide range of visual acuities, and the new eye chart was especially suitable for the detection of amblyopia risk factors and low vision examination in children (3-5y of age). It can be applied in routine clinical practice.
介绍一种适用于3至5岁儿童的新型近视力表及其临床应用。
基于韦伯-费希纳定律设计了一种新型近视力表，该视力表将贝利-洛维布局与一组新设计的对称符号相结合。它由15行对称符号组成，对应视力范围为1.3至0.1 logMAR。视标为红色，背景为白色，由四种基本几何符号（圆形、方形、三角形和十字形）特别设计而成，符合学龄前儿童的认知水平。视标大小和分布采用规则的几何级数排列在15行中。两行视标大小的级数比为1.2589，还包括两组较小的视标，范围从0.7至 -0.1 logMAR，用于重复测试。近视力以logMAR或小数记录，测试距离为25厘米。
这种新型近视力表配有由4种不同符号（三角形、方形、十字形和圆形）组成的儿童视力测试视标，符合国家和国际视力表设计指南。在对学龄前儿童（3至5岁）进行近视力评估时，它克服了儿童无法识别字母表字母以及难以指明如翻转“E”或兰多尔特“C”等黑色抽象符号方向的问题，而这些问题容易使受试者失去兴趣。近视力可以用不同的表示法记录：小数视力和logMAR。在这种新型近视力表中，这两种表示法可以轻松相互转换。该新型视力表的测量结果不仅与中国国家标准对数近视力表显示出显著相关性和良好一致性（r = 0.932，P < 0.01），而且还表明具有良好的重测信度（89%的重测分数在初始测试分数的0.1 logMAR单位范围内）和高应答率。
本研究结果支持使用新型近视力表对3至5岁儿童进行近视力测量的有效性和可靠性，该新型视力表尤其适用于检测儿童（3至5岁）的弱视危险因素和低视力检查。它可应用于常规临床实践。
