McGill Vision Research, Department of Ophthalmology, McGill University, Montreal, QC, Canada.
Restor Neurol Neurosci. 2010;28(6):793-802. doi: 10.3233/RNN-2010-0550.
The present treatments for amblyopia are predominantly monocular aiming to improve the vision in the amblyopic eye through either patching of the fellow fixing eye or visual training of the amblyopic eye. This approach is problematic, not least of which because it rarely results in establishment of binocular function. Recently it has shown that amblyopes possess binocular cortical mechanisms for both threshold and suprathreshold stimuli.
We outline a novel procedure for measuring the extent to which the fixing eye suppresses the fellow amblyopic eye, rendering what is a structurally binocular system, functionally monocular.
Here we show that prolonged periods of viewing (under the artificial conditions of stimuli of different contrast in each eye) during which information from the two eyes is combined leads to a strengthening of binocular vision in strabismic amblyopes and eventual combination of binocular information under natural viewing conditions (stimuli of the same contrast in each eye). Concomitant improvement in monocular acuity of the amblyopic eye occurs with this reduction in suppression and strengthening of binocular fusion. Furthermore, in a majority of patients tested, stereoscopic function is established.
This provides the basis for a new treatment of amblyopia, one that is purely binocular and aimed at reducing suppression as a first step.
目前治疗弱视的方法主要是单眼治疗，旨在通过遮盖健眼或弱视眼的视觉训练来提高弱视眼的视力。这种方法存在问题，其中最主要的问题是，它很少能建立双眼功能。最近的研究表明，弱视患者的大脑皮层对于阈下和阈上刺激都存在双眼机制。
我们概述了一种新的方法来测量注视眼抑制弱视眼的程度，从而使原本是一个结构上的双眼系统，在功能上变成单眼。
我们发现，在斜视性弱视患者中，长时间观看（在双眼刺激对比度不同的人为条件下）会导致双眼视觉增强，并且最终在自然观看条件下（双眼刺激对比度相同）会结合双眼信息。随着抑制作用的降低和双眼融合的增强，弱视眼的单眼视力也会相应提高。此外，在大多数接受测试的患者中，立体视觉功能也得到了建立。
这为弱视的新治疗方法提供了基础，该方法完全是双眼治疗，旨在首先减少抑制。
