VISUAL DYSFUNCTION IN RETINITIS PIGMENTOSA

色素性视网膜炎的视觉功能障碍

• 批准号: 2391722
• 负责人: KENNETH R. ALEXANDER
• 金额: $ 15.69万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-04-01 至 1998-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2391722
• 关键词: behavioral /social science research tag; cataract; fovea centralis retinae; human subject; light adaptations; light scattering; neural information processing; psychophysics; retina disorder; retinitis pigmentosa; space perception; vision tests; visual feedback; visual fields; visual perception; visual phototransduction

Retinitis pigmentosa (RP) is one of the most frequently occurring blinding retinal dystrophies and is characterized not only by the loss of rod function but also by cone system abnormalities as well. This research proposal is focussed on foveal contrast perception in RP: the origin of contrast processing deficits and their impact on foveal visual function. Parallel investigations of normal control subjects will better define mechanisms of contrast processing in visually normal individuals. The specific aims are: (1) to test particular hypotheses concerning the loss of foveal spatial vision in RP (hypothesis 1: selective loss of input to high spatial frequency mechanisms; hypothesis 2: altered foveal spatial grain; hypothesis 3: reduced contrast gain); (2) to determine the relationship between intraocular light scatter, posterior subcapsular lens opacities. disability glare, and foveal visual function in patients with RP and related photoreceptor degenerations; (3) to define the relative contributions of linear and nonlinear mechanisms to spatial and temporal contrast sensitivity in RP patients and in visually normal individuals; and (4) to test the hypothesis that contrast thresholds for letter identification are mediated by the same visual mechanism as contrast thresholds for the detection of sinusoidal gratings. These aims will be accomplished by a series of interrelated psychophysical investigations of foveal vision loss in a cohort of approximately 1,000 well-categorized patients with RP, many with identified mutations in the genes involved in rod phototransduction, available through the University of Illinois Research Center of the National Retinitis Pigmentosa Foundation Fighting Blindness. The results of these studies are intended to lead to clinically applicable methods that will allow an earlier detection of foveal vision loss in RP patients, to a more precise characterization of foveal visual impairment in individual patients, to the optimization of strategies for visual rehabilitation, and to a more sensitive evaluation of potential methods for therapeutic intervention.

色素性视网膜炎（RP）是最常发生的一种 视网膜营养不良的盲目，不仅以损失为特征 杆功能的功能，也通过锥体系统异常。这 研究提案的重点是RP中的动脉对比感知： 对比处理缺陷的起源及其对中央凹视觉的影响 功能。对正常对照受试者的平行研究将更好 定义视觉正常个体中对比处理的机制。 具体目的是：（1）测试有关该特定假设 RP中动脉空间视觉的丧失（假设1：选择性损失 输入高空间频率机制；假设2：动脉凹改变 空间谷物；假设3：减少对比度增益）； （2）确定 眼内光散射，后囊 镜头不熟悉。患者的残疾眩光和中央凹的视觉功能 带有RP和相关的感受者退化； （3）定义 线性和非线性机制对空间和非线性机制的相对贡献 RP患者和视觉正常的时间对比度灵敏度 个人（4）检验的假设是对比阈值 字母识别与相同的视觉机制介导 检测正弦光栅的对比阈值。这些目标 将通过一系列相互关联的心理物理来完成 大约1,000的同类中央凹视力丧失的调查 RP分类良好的患者，许多患者在 涉及杆光转导的基因，可通过大学获得 伊利诺伊州国家视网膜炎色素炎的研究中心 基础斗争失明。这些研究的结果旨在 导致临床适用的方法，该方法将允许更早 发现RP患者中央凹视力丧失，更精确 表征单个患者中央凹视觉障碍的表征 优化视觉康复的策略，以及更多 对治疗干预的潜在方法的敏感评估。