Momeni-Moghaddam Hamed, Yekta Abbas A, Ehsani Marzieh, Kundart James
Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.
Strabismus. 2012 Dec;20(4):166-74. doi: 10.3109/09273972.2012.735337.
The purpose of this study is the evaluation of fixation disparity curve (FDC) parameters with an instrument that includes a central fusion lock (the modified near Mallett unit) and another without one (the Wesson fixation disparity card) to determine which is useful for diagnosis of symptomatic from asymptomatic subjects.
In this analytical-descriptive study, 100 students were selected randomly and divided into symptomatic and asymptomatic groups. FDC parameters were determined with the Wesson card and the modified near Mallett unit for each subject and compared in symptomatic and asymptomatic groups. Data were analyzed by Wilcoxon, Mann-Whitney U, Spearman correlation coefficient and Chi-square tests.
The mean slope, y-intercept, and x-intercept with the Mallett unit and the Wesson card were significantly different in the symptomatic and asymptomatic groups (p < 0.001). Significant correlations were obtained between the Mallett unit and the Wesson card in y-intercept, x-intercept and slope (p < 0.001). There was a significant difference in the distributions of fixation disparity curve types in the two symptom groups with the Mallett unit (p = 0.01) and the Wesson card (p = 0.002) by Chi-square test.
Among symptomatic participants in this study, both Type I and Type III FD are more common than previously thought, but depend upon the method used to measure it. The x-intercepts were on average displaced in the base-in direction, y-intercepts were shifted in the exo direction, and the slopes were steeper with the Wesson FD card compared with the modified near Mallett unit. This may be related to the design of two devices. These differences were more significant in the symptomatic group.
本研究旨在使用一种带有中央融合锁的仪器（改良型近视力马利特装置）和另一种不带中央融合锁的仪器（韦森注视差异卡片）评估注视差异曲线（FDC）参数，以确定哪一种对有症状和无症状受试者的诊断有用。
在这项分析描述性研究中，随机选取100名学生，分为有症状组和无症状组。为每位受试者使用韦森卡片和改良型近视力马利特装置测定FDC参数，并在有症状组和无症状组之间进行比较。数据采用威尔科克森检验、曼 - 惠特尼U检验、斯皮尔曼相关系数和卡方检验进行分析。
有症状组和无症状组使用马利特装置和韦森卡片时，平均斜率、y轴截距和x轴截距有显著差异（p < 0.001）。马利特装置和韦森卡片在y轴截距、x轴截距和斜率方面存在显著相关性（p < 0.001）。通过卡方检验，在两种症状组中，使用马利特装置（p = 0.01）和韦森卡片（p = 0.002）时，注视差异曲线类型的分布存在显著差异。
在本研究的有症状参与者中，I型和III型注视差异比以前认为的更常见，但取决于测量方法。与改良型近视力马利特装置相比，韦森注视差异卡片的x轴截距平均向集合方向移位，y轴截距向外斜视方向移位，斜率更陡。这可能与两种设备的设计有关。这些差异在有症状组中更为显著。
