Visual Dysfunction in Retinal Degenerations

视网膜变性引起的视觉功能障碍

• 批准号: 6773904
• 负责人: KENNETH R. ALEXANDER
• 金额: $ 23.38万
• 依托单位: UNIVERSITY OF ILLINOIS AT 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 2006-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6773904
• 关键词: behavioral /social science research tag; clinical research; cone cell; early diagnosis; electrophysiology; electroretinography; evoked potentials; gene mutation; human subject; light adaptations; motion perception; neural information processing; psychophysics; retina degeneration; retinitis pigmentosa; rod cell; space perception; vision tests; visual feedback; visual fields; visual perception; visual photoreceptor; visual phototransduction

DESCRIPTION (provided by applicant): Spatial and temporal variations in contrast are a fundamental source of information about the visual environment. Therefore, the disruption of contrast processing due to retinal disease can potentially have a profound effect on the quality of life of persons afflicted with retinal degenerations. Because relatively little is known about the nature of contrast processing deficits in retinal diseases, the proposed studies will evaluate contrast coding through the use of innovative and sophisticated testing methods, including psychophysics, electroretinography (ERG), and the visual evoked potential (VEP), that are intended to target specific visual subsystems that can be affected differently by retinal pathology. The studies are focused on retinitis pigmentosa (RP), a group of hereditary retinal dystrophies that are the most frequent genetic cause of blindness in adults. Parallel investigations of control subjects will better define mechanisms of contrast processing in visually normal persons. The specific aims are: (1) to define the origin and relative contribution of postreceptoral processes to implicit time delays in the ERG of the cone system of patients with RP; (2) to identify the mechanisms underlying deficits in foveal contrast sensitivity in RP within the framework of magnocellular (MC) and parvocellular (PC) pathways; (3) to determine whether deficits in suprathreshold contrast discrimination in RP represent changes in response scaling or changes in effective contrast within the MC and PC pathways; and (4) to establish whether letter optotypes and grating stimuli provide equivalent measures of contrast sensitivity deficits in retinal disease. These aims will be accomplished through a series of studies that will test subjects recruited from a cohort of more than 1,200 well-categorized patients with RP, available through the University of Illinois Research Center of The Foundation Fighting Blindness. Given recent developments in understanding the molecular genetic basis for sight-threatening hereditary retinal dystrophies, and with clinical trials of therapeutic intervention being planned, the proposed studies are intended to provide a rational basis for developing new, more sensitive testing methods that will be of clinical value in monitoring the visual status of persons with eye disease and in assessing the outcome of potential treatment regimens.

描述（由申请人提供）：对比中的空间和时间变化是有关视觉环境的基本信息来源。因此，由于视网膜疾病引起的对比处理的破坏可能会对患有视网膜退化的人的生活质量产生深远的影响。由于对视网膜疾病中的对比处理缺陷的性质知之甚少，因此拟议的研究将通过使用创新和复杂的测试方法来评估对比度编码，包括心理物理学，电遗传学（ERG）（ERG）和视觉诱发的势能（VEP），这些（VEP）可以通过靶向特定的视觉子系统来靶向特定的视觉子系统，从而通过对其进行不同的视觉效果。这些研究集中在色素性视网膜炎（RP）上，这是一群遗传性视网膜营养不良，是成年人失明的最常见遗传原因。对照对象的平行研究将更好地定义视觉正常人中对比处理的机制。具体目的是：（1）定义后过程对RP患者锥体系统中隐式时间延迟的起源和相对贡献； （2）确定在大细胞（MC）和副细胞（PC）途径的框架内，RP中凹入对比敏感性的机制； （3）确定RP上方的对比度歧视的缺陷是否表示响应缩放的变化或MC和PC途径内有效对比度的变化； （4）确定字母的选择和光刺激是否提供了视网膜疾病中对比度敏感性缺陷的等效度量。这些目标将通过一系列研究来实现，该研究将测试从伊利诺伊大学研究中心（University of Illinois Research Center）抗击盲目的伊利诺伊大学研究中心，可从1,200多名RP分为RP的患者中招募的受试者。鉴于最新的发展，了解视力遗传性视网膜营养不良的分子遗传基础，以及计划进行治疗干预的临床试验，拟议的研究旨在为开发新的，更敏感的测试方法提供合理的基础，这些方法将具有临床价值，从而在监测眼病的视觉状态和评估临床治疗方面的临床价值。