Schor C
School of Optometry, University of California, Berkeley.
Am J Optom Physiol Opt. 1988 May;65(5):341-8. doi: 10.1097/00006324-198805000-00006.
It is customary to describe abnormal interactions between accommodation and convergence according to the Duane-White classification of convergence excess and insufficiency or divergence excess and insufficiency. However, recent studies indicate that these extremely high and low categories of accommodative vergence may result from adaptive disorders of accommodation and convergence. The AC/A ratio is shown in this paper to vary inversely with adaptability of accommodation and to vary directly with adaptability of vergence. Extremely high AC/A ratios can result from an imbalance in which vergence adapts readily to prism, whereas accommodation does not adapt to minus lenses. Similarly, extremely high values for convergence accommodation (the CA/C ratio) are observed when there is robust adaptation of accommodation to lenses and little adaptation of vergence to prism. Furthermore, in these extreme cases the AC/A and CA/C ratios tend to be inversely related. For example, abnormally high AC/A ratios are often accompanied by extremely low CA/C ratios and vice versa. These observations suggest that equalizing the adaptability of accommodation and vergence with orthoptics may prove to be an effective means of restoring the AC/A and CA/C ratios to normal values.
通常根据杜安 - 怀特对集合过度与不足或散开过度与不足的分类来描述调节与集合之间的异常相互作用。然而，最近的研究表明，这些极高和极低类别的调节性聚散可能是由调节和集合的适应性障碍引起的。本文表明，AC/A比率与调节适应性成反比，与聚散适应性成正比。极高的AC/A比率可能是由于一种失衡导致的，即聚散很容易适应棱镜，而调节却不适应负透镜。同样，当调节对透镜有强烈适应而聚散对棱镜几乎没有适应时，会观察到集合近点（CA/C比率）的极高值。此外，在这些极端情况下，AC/A和CA/C比率往往呈负相关。例如，异常高的AC/A比率通常伴随着极低的CA/C比率，反之亦然。这些观察结果表明，通过视轴矫正法使调节和聚散的适应性相等可能是将AC/A和CA/C比率恢复到正常值的有效方法。
