Casillas Casillas Elizabeth, Rosenfield Mark
Department of Optometry, Universidad Autonoma de Aguascalientes, Aguascalientes, Mexico.
Optom Vis Sci. 2006 Apr;83(4):237-41. doi: 10.1097/01.opx.0000214316.50270.24.
Subjective measurement of the oculomotor deviation at both distance and near is a standard test in optometric practice. A number of procedures are available to the practitioner, and previous studies have demonstrated differences in the repeatability of many of the techniques. However, it is unclear whether testing the subject through a phoropter or in free space (trial frame) will alter the oculomotor deviation.
Distance and near heterophoria was measured in 60 visually normal subjects between 20 and 34 years of age using the Von Graefe (VG), Maddox Rod (MR), and Modified Thorington (MT) procedures. The deviation was assessed for viewing distances of 6 m and 0.40 m using both a phoropter and trial frame. To examine the repeatability of each technique, the deviation was measured on two separate occasions for each procedure, with the two sessions being separated by at least 24 hours.
The mean vertical deviations at both distance and near were extremely close to orthophoria, and only minimal variation was observed. However, the MR procedure, when used with a trial frame, gave the best repeatability for measuring vertical deviations both at distance and near. Regarding horizontal deviations, the repeatability was better for all three procedures when using a trial frame compared with the phoropter. The best repeatability at distance and near was observed when the MT and MR techniques, respectively, were used with the trial frame. Consistent with previous reports, the VG procedure had poor repeatability, especially when used with the phoropter, and the mean findings showed a greater exo deviation when compared with the other two techniques.
Testing oculomotor deviations in free space provides a more repeatable response than when using a phoropter. Accordingly, we recommend that subjective measurements of heterophoria in the clinical setting can best be quantified using either the MR or MT techniques in free space.
在验光实践中，对远距离和近距离的眼动偏差进行主观测量是一项标准测试。从业者有多种方法可供选择，先前的研究表明许多技术在可重复性方面存在差异。然而，通过综合验光仪或在自由空间（试验框架）中对受试者进行测试是否会改变眼动偏差尚不清楚。
使用冯·格拉费（VG）、马多克斯杆（MR）和改良索林顿（MT）方法，对60名年龄在20至34岁之间的视力正常受试者进行远距离和近距离隐斜视测量。使用综合验光仪和试验框架评估6米和0.40米观看距离时的偏差。为了检验每种技术的可重复性，每种方法在两个不同的时间进行测量，两次测量之间至少间隔24小时。
远距离和近距离的平均垂直偏差都非常接近正视，仅观察到极小的变化。然而，MR方法与试验框架一起使用时，在测量远距离和近距离的垂直偏差方面具有最佳的可重复性。关于水平偏差，与综合验光仪相比，使用试验框架时所有三种方法的可重复性都更好。分别使用MT和MR技术与试验框架时，在远距离和近距离观察到最佳的可重复性。与先前的报告一致，VG方法的可重复性较差，尤其是与综合验光仪一起使用时，并且平均结果显示与其他两种技术相比有更大的外斜视偏差。
在自由空间中测试眼动偏差比使用综合验光仪能提供更可重复的结果。因此，我们建议在临床环境中对隐斜视进行主观测量时，最好使用自由空间中的MR或MT技术进行量化。
