Devi Preetirupa, Bhengra Christa M, Kumar Deepak, Deshmukh Rashmi, Vaddavalli Pravin K, Solomon Joshua A, Tyler Christopher W, Bharadwaj Shrikant R
Centre for Applied Vision Research, City St. George's, University of London, Northampton Square, London, United Kingdom.
Brien Holden Institute of Optometry and Vision Sciences, L V Prasad Eye Institute, Hyderabad, Telangana, India.
Invest Ophthalmol Vis Sci. 2025 Apr 1;66(4):31. doi: 10.1167/iovs.66.4.31.
The purposes of this study were to quantify the impact of degraded binocularity in keratoconus and its improvement with rigid contact lenses on a depth-related visuomotor task that emulates complex activities in daily living; and to determine whether visuomotor performance may be predicted from psychophysical estimates of stereo threshold.
Participants were instructed to pass a metal loop around a wire convoluted in depth. Error rate and speed were measured in 26 controls, 30 cases with keratoconus with best-corrected spectacles, a subset of 17 cases with rigid contact lenses, and 10 uncorrected myopes with acuity and stereo thresholds comparable to the keratoconic cohort. Stereo thresholds were determined using random-dot stimuli.
Binocular error rates were lower than monocular error rates for controls, uncorrected myopes, and the better-performing half of cases (p < 0.001, for each), but not for the worst-performing half (p = 0.07). Error rates in cases improved with contact lenses (p < 0.001). Within each cohort, the error rate was poorly correlated with the stereo threshold (r2 < 0.12, for each). Monocular speeds were significantly lower than binocular speeds for controls than for cases (p = 0.003) and for uncorrected myopes than cases (p = 0.001).
Degraded binocularity in keratoconus may limit the ability to perform depth-related visuomotor tasks. A portion of this loss may be overcome by using rigid contact lenses. The attributes of visuomotor task performance are, however, not predictable from the psychophysical estimates of stereo thresholds.
本研究的目的是量化圆锥角膜双眼视功能下降及其通过硬性接触镜改善后对一项与深度相关的视觉运动任务的影响，该任务模拟了日常生活中的复杂活动；并确定视觉运动表现是否可以从立体视阈值的心理物理学估计中预测出来。
指导参与者将一个金属环套在一根深度盘绕的金属丝上。测量了26名对照组、30名佩戴最佳矫正眼镜的圆锥角膜患者、17名佩戴硬性接触镜的患者子集以及10名视力和立体视阈值与圆锥角膜患者相当的未矫正近视患者的错误率和速度。使用随机点刺激确定立体视阈值。
对照组、未矫正近视患者以及表现较好的一半圆锥角膜患者的双眼错误率低于单眼错误率（每组p<0.001），但表现最差的一半患者并非如此（p = 0.07）。佩戴接触镜后圆锥角膜患者的错误率有所改善（p<0.001）。在每个队列中，错误率与立体视阈值的相关性较差（每组r2<0.12）。对照组的单眼速度显著低于双眼速度，圆锥角膜患者（p = 0.003）以及未矫正近视患者低于圆锥角膜患者（p = 0.001）。
圆锥角膜患者双眼视功能下降可能会限制执行与深度相关的视觉运动任务的能力。使用硬性接触镜可以部分克服这种能力丧失。然而，视觉运动任务表现的属性无法从立体视阈值的心理物理学估计中预测出来。
