McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University; McGill University Health Center, Montreal, QC, Canada.
J Vis. 2024 Oct 3;24(11):2. doi: 10.1167/jov.24.11.2.
In binocular vision, the relative strength of the input from the two eyes can have significant functional impact. These inputs are typically balanced; however, in some conditions (e.g., amblyopia), one eye will dominate over the other. To quantify imbalances in binocular vision, we have developed the Dichoptic Contrast Ordering Test (DiCOT). Implemented on a tablet device, the program uses rankings of perceived contrast (of dichoptically presented stimuli) to find a scaling factor that balances the two eyes. We measured how physical interventions (applied to one eye) affect the DiCOT measurements, including neutral density (ND) filters, Bangerter filters, and optical blur introduced by a +3-diopter (D) lens. The DiCOT results were compared to those from the Dichoptic Letter Test (DLT). Both the DiCOT and the DLT showed excellent test-retest reliability; however, the magnitude of the imbalances introduced by the interventions was greater in the DLT. To find consistency between the methods, rescaling the DiCOT results from individual conditions gave good results. However, the adjustments required for the +3-D lens condition were quite different from those for the ND and Bangerter filters. Our results indicate that the DiCOT and DLT measures partially separate aspects of binocular imbalance. This supports the simultaneous use of both measures in future studies.
在双眼视觉中，来自两只眼睛的输入相对强度可能会产生显著的功能影响。这些输入通常是平衡的；然而，在某些情况下（例如弱视），一只眼睛会比另一只眼睛更占优势。为了量化双眼视觉的不平衡，我们开发了双眼对比排序测试（DiCOT）。该程序在平板电脑设备上运行，使用感知对比度的排名（呈现给双眼的刺激）来找到平衡两只眼睛的缩放因子。我们测量了物理干预（应用于一只眼睛）如何影响 DiCOT 测量，包括中性密度（ND）滤光片、Bangerter 滤光片以及 +3 屈光度（D）镜片引入的光学模糊。DiCOT 结果与双眼字母测试（DLT）的结果进行了比较。DiCOT 和 DLT 均表现出极好的重测信度；然而，干预措施引入的不平衡程度在 DLT 中更大。为了在方法之间找到一致性，对个别条件下的 DiCOT 结果进行重新缩放可获得良好的结果。然而，+3-D 镜片条件所需的调整与 ND 和 Bangerter 滤光片的调整完全不同。我们的结果表明，DiCOT 和 DLT 测量部分分离了双眼不平衡的方面。这支持在未来的研究中同时使用这两种测量方法。
