立体视正常值变化观察

目的:比较Frisby、Randot、Howard-Dolman三种立体视检查方法的可重复性,确定此三种临床用立体视检查方法的正常值变化的95%可信区间.方法:选择26位无斜视、弱视和眼手术史的健康个体,平均年龄为24.42±4.26岁(14～32岁),所有的受检者具有正常的双眼视且双眼视力为6/6.测量视远瞳距和习惯视力后,以随机的顺序用Frisby、Randot、Howard-Dolman三种检查方法测量立体视,测量时保持光照度为670lx.约1周后在相同的测量条件下同样用三种检查方法测量立体视,平均间隔时间为7.8±2.4天.结果:三种临床立体视检查方法的可重复性系数分别为±2.7"(Frisby)、±8.0"(Randot)和±9.3"(Howard-Dolman),再次试验的平均值低于首次试验的平均值,t检验提示这改变差异无显著性意义(P>0.05).重复试验的相关系数分别为0.91(Frisby)、0.56(Randot)、0.60(Howard-Dolman).三种检查方法之间的相关系数分别为0.31、0.31、0.33.结论:三种临床立体视检查方法的相关性较差.Frisby检查法有最好的重复性和正常值有较小的范围.用该法测得成年人立体视改变的95%可信区间为±2.7".如果用Frisby法测得年轻成年人的立体视的变化超过这个范围,可认为是有显著意义的临床改变.

The detection of change in stereoacuity

Objective:To compare the repeatability of the Frisby, Randot and Howard-Dolman stereotests, and to determine the 95% confidence limits for the change of each test.Methods:Stereoacuity using the three clinical stereoacuity tests was measured in 26 healthy adult subjects with normal binocular vision. The subjects were retested approximately one week later.Results:The coefficients of repeatability for the three tests were ±2.7" (Frisby) ±8.0" (Randot) and ±9.3" (Howard-Dolman) and test-retest correlation coefficients were 0.91 (Frisby), 0.56 (Randot) and 0.60 (Howard-Dolman).Conclusion:The Frisby test showed the best repeatability and smallest range of normal values. For young adults, the 95% confidence limits for change were calculated to be ± 2.7". If a young adult's stereoacuity measured with the Frisby test changes by more than this amount, then this should be considered a significant clinical change.