Optimal magnification and oculomotor strategies in low vision patients

项目摘要 伴有双眼中央暗点的低视力患者通常会在靠近中央暗点的位置形成首选的视网膜位置(PRL) 暗点的边缘，试图替代丢失的中心凹。然而，在功能上，PRL达不到 挑战和此类患者的视力和对比敏感度较差，眼球运动控制较差，以及 经常丢失感兴趣的物体附近的知觉填充的双眼暗点。我们正在提议一项 利用实时数字对这些患者进行低视力增强和低视力康复的新方法 在头盔显示器中双目呈现的大视场图像的处理和重新映射 配备了视频场景摄像头和眼睛和头部追踪器。具体地说，我们建议测试这些好处 以及一种名为HMD-泡泡的创新视力增强策略的副作用，这是一种局部的 来自安装在头上的摄像机的视频图像中的放大和对比度增强区域 安装显示器(HMD)。我们实现了两种类型的HMD-气泡：“固定的”HMD-气泡 其中，放大率区域相对于显示坐标是“固定的”，而“眼球跟踪”HMD气泡 放大区域跟随患者的眼球运动。放大的大小、形状和级别 两个HMD气泡的大小均可由患者动态调整，允许定制HMD气泡。 固定的HMD气泡对患者来说相对容易使用。然而，眼睛跟踪HMD-气泡是 一般来说，患者很难控制他们第一次使用它的时间，这就需要进行锻炼 和培训计划。由于眼睛运动比头部运动更快，眼睛跟踪HMD-气泡 应该优于固定气泡，如果患者能学会控制的话。我们还将调查潜在的 在头盔显示器气泡内部和/或周围提供立体双目信息的好处，因为这一步可以说是 目前最重要的剩余发展是头盔显示器视觉增强系统..目标1是 测量双眼中央暗点低视力患者在日常相关任务中的表现 使用固定或眼球跟踪头盔显示器气泡时会存活。表现指标包括阅读、面部护理 表情识别和识别，眼手协调，以及执行的速度和准确性 选定的日常生活任务。我们还会定期测量与模拟器相关的不适严重程度 疾病“。目标2是开发和评估旨在帮助患者适应的练习和培训计划 并优化使用HMD气泡。目标3是确定立体双目信息在和/或 HMD周围的气泡对患者有潜在的好处。我们将使用单目和双目对比 敏感度测量以确定是否发生双眼抑制或抑制，并测量 相应的视网膜点数，以确定患者是否能获得单眼双眼视觉，以及在多大程度上 放大泡泡会扭曲星座。最后，我们将探索患者控制疾病的能力 双目眼球跟踪气泡，同时做出收敛的眼球运动。

PROJECT ABSTRACT Low vision patients with bilateral central scotomas usually develop a preferred retinal locus (PRL) close to the border of the scotoma that tries to substitute for the lost foveae. However, functionally the PRL falls short of the challenge and such patients have poor visual acuity and contrast sensitivity, poor oculomotor control, and frequently lose objects of interest in the nearby perceptually filled-in binocular scotoma. We are proposing a new approach to low vision enhancement and low vision rehabilitation for these patients using real-time digital processing and remapping of large field of view images presented binocularly in a head-mounted display equipped with video scene cameras and eye and head trackers. Specifically, we propose testing the benefits and side-effects of an innovative vision enhancement strategy called the HMD-bubble, which is a localized region of magnification and contrast enhancement in a video image from a camera mounted on a head mounted display (HMD). There are two types of HMD-bubbles we have implemented: the "fixed" HMD-bubble where the region of magnification is "fixed" relative to display coordinates, and the "eye tracking" HMD-bubble where the region of magnification follows patients' eye movements. The size, shape, and level of magnification of both HMD-bubbles can be dynamically adjusted by the patient, allowing customization of the HMD-bubbles. The fixed HMD-bubble is relatively easy for patients to usel. The eye tracking HMD-bubble however is generally much harder for patients to control when they first use it, necessitating the development of exercises and training programs. Since eye movements are faster than head movements, the eye tracking HMD-bubble should be superior to the fixed bubble, if patients can learn to control it. We will also investigate the potential benefits of providing stereo binocular information in and/or around a HMD-bubble, as that step is arguably the most important remaining development at this time with HMD vision enhancement systems.. Aim 1 is to measure the performance of low vision patients with bilateral central scotomas in tasks relevant to their daily lives when using a fixed or eye tracking HMD-bubble. The performance measures include reading, facial expression recognition and identification, eye-hand coordination, and speed and accuracy of performing selected daily living tasks. We also will periodically measure discomfort severity associated with “simulator sickness”. Aim 2 is to develop and evaluate exercises and training programs designed to help patients adjust to and optimize the use of a HMD-bubble. Aim 3 is to determine if stereo binocular information in and/or around HMD-bubbles is of potential benefit to patients. We will use monocular and binocular contrast sensitivity measures to determine if binocular inhibition or suppression is occurring and measure the location of corresponding retinal points to determine if the patient can attain single binocular vision and to what extent the magnification bubble distorts the horopter. Finally, we will explore patients’ capabilities of controlling the binocular eye tracking bubble while making vergence eye movements.