Goss D A, Jackson T W
School of Optometry, Indiana University, Bloomington, USA.
Optom Vis Sci. 1996 Apr;73(4):269-78. doi: 10.1097/00006324-199604000-00009.
Some contemporary theories of the etiology of youth onset myopia suggest differences in accommodation and convergence function. Previous studies have related esophoria to various aspects of myopia development. This paper examines whether differences in phorias exist before the onset of myopia.
A cohort of initially emmetropic children had eye and vision examinations at 6-month intervals for a period of 3 years. Dissociated phorias were measured by the von Graefe method. These prospective data were analyzed by: (1) comparing phorias in children who became myopic to those in children who remained emmetropic; (2) determination of sensitivity and specificity of phorias to distinguish between children who became myopic and those who did not; and (3) determining the change in phorias with time. These same analyses were also performed as additional analyses of some previously published retrospective private practice data.
Distance phorias were not significantly different in the became-myopic and remained-emmetropic group by the Mann Whitney U test in either the private practice data or the prospective data. The near phoria was more convergent in the became-myopic group than in the remained-emmetropic group in the private practice data (p < 0.02 by Mann Whitney U test). In the prospective data there were proportionately more children who became myopic outside the near phoria range of 3 delta exo to 1 delta eso (p < 0.05 by chi 2 test). In both data sets the near phoria showed an eso shift with time in the children who became myopic, beginning before and continuing after the onset of myopia. The children in the remained-emmetropic groups did not show eso shifts in near phoria.
A near phoria which is not close to orthophoria appears to be a risk factor for youth onset myopia, but sensitivity and specificity were not as high as those for other variables such as corneal power, axial length to corneal radius ratio, positive relative accommodation (PRA), and midpoint of the near fusional vergence range. The onset of myopia is associated with an eso (convergent) shift in the near phoria.
一些当代关于青少年近视病因的理论表明调节和集合功能存在差异。先前的研究已将内隐斜与近视发展的各个方面联系起来。本文研究在近视发病前是否存在隐斜差异。
一组最初正视的儿童进行为期3年的眼部和视力检查，每隔6个月检查一次。用von Graefe法测量分离性隐斜。这些前瞻性数据通过以下方式进行分析：（1）比较近视儿童与仍为正视的儿童的隐斜情况；（2）确定隐斜区分近视儿童和非近视儿童的敏感性和特异性；（3）确定隐斜随时间的变化。这些相同的分析也作为对一些先前发表的回顾性私人诊所数据的补充分析进行。
在私人诊所数据或前瞻性数据中，通过Mann-Whitney U检验，近视组和正视组的远距离隐斜无显著差异。在私人诊所数据中，近视组的近距离隐斜比正视组更偏向集合（通过Mann-Whitney U检验，p<0.02）。在前瞻性数据中，在近距离隐斜范围从3△外隐斜到1△内隐斜之外近视的儿童比例更高（通过卡方检验，p<0.05）。在两个数据集中，近视儿童的近距离隐斜随时间显示内隐斜偏移，在近视发病前开始并在发病后持续。正视组儿童的近距离隐斜未显示内隐斜偏移。
不接近正位隐斜的近距离隐斜似乎是青少年近视的一个危险因素，但敏感性和特异性不如角膜屈光度、眼轴长度与角膜半径比、正相对调节（PRA）以及近距离融合性聚散范围中点等其他变量。近视的发病与近距离隐斜的内隐斜（集合）偏移有关。
