Visual Dysfunction in Retinal Degenerations

视网膜变性引起的视觉功能障碍

• 批准号: 7677273
• 负责人: KENNETH R. ALEXANDER
• 金额: $ 24.28万
• 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 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7677273
• 关键词: Address; Adult; Age; Blindness; Characteristics; Classification; Clinical; Clinical Trials; Code; Complex; Contrast Sensitivity; Defect; Detection; Discrimination; Disease; Disease Progression; Electroretinography; Environment; Evaluation; Exhibits; Feedback; Foundations; Frequencies; Functional disorder; Genetic; Grant; Illinois; Individual; Inherited; Investigation; Lead; Letters; Life; Methods; Molecular Genetics; Monitor; Nature; Outcome; Pathway interactions; Patients; Performance; Periodicity; Persons; Phase; Photoreceptors; Phototransduction; Process; Property; Psychophysiology; Quality of life; Recruitment Activity; Reporting; Research; Research Personnel; Retina; Retinal; Retinal Cone; Retinal Degeneration; Retinal Diseases; Retinitis Pigmentosa; Stimulus; Subgroup; System; Techniques; Testing; Therapeutic; Therapeutic Intervention; Time; Universities; Variant; Vision; Vision Disorders; Visual; Visual Acuity; Visual Pathways; Visual Psychophysics; Visual system structure; Work; base; cohort; computerized data processing; design; fighting; improved; indexing; innovation; insight; luminance; magnocellular; novel; novel strategies; parvocellular; programs; response; spatiotemporal; tool; visual process; visual processing

DESCRIPTION (provided by applicant): The ability to perceive variations in contrast within the visual environment is often compromised in individuals who are undergoing retinal degeneration, and this can lead to problems in carrying out tasks of daily living. However, relatively little is known about the specific ways in which contrast coding is altered in retinal diseases. To address this deficiency, four distinct projects are proposed that have as a common theme the evaluation of spatial and temporal deficits in contrast processing within the cone system of patients with retinitis pigmentosa (RP), a group of night-blinding, hereditary retinal degenerations that are the most frequent genetic cause of blindness in adults. Concurrent investigations of contrast coding in visually normal individuals will provide new insights into the underlying mechanisms of visual processing within the normal visual system. The specific aims are: (1) to resolve an apparent contradiction between deficits in luminance contrast detection and contrast discrimination within the inferred magnocellular and parvocellular pathways in patients with RP; (2) to define the object spatial frequencies that are optimal for evaluating letter contrast sensitivity and visual acuity in retinal degenerations; (3) to determine the retinal origin and generality of a phase lag of the L-cone-driven flicker electroretinogram (ERG) in RP; and (4) to characterize the properties of synchronous period doubling in the flicker ERG of visually normal individuals and patients with RP in order to clarify the nature of the underlying mechanism. These aims will be addressed by novel and innovative psychophysical and ERG techniques applied to individuals recruited from a cohort of more than 1,400 well- categorized patients with RP, available under the auspices of the University of Illinois Research Center of The Foundation Fighting Blindness, and to age-equivalent individuals with normal vision. Recent breakthroughs have increased our understanding of the molecular genetic basis for sight-threatening retinal degenerations, and potential strategies for therapeutic interventions are under investigation, but the standard clinical methods for evaluating the functional integrity of the visual system have known limitations. The studies proposed in this application are intended to provide new methods for monitoring visual dysfunction in persons with retinal degenerations, for identifying more homogeneous patient subgroups for inclusion in clinical trials, and for evaluating the outcome of potential therapeutic strategies.

描述（由申请人提供）：在进行视网膜变性的个体中通常会损害视觉环境中对比度变化的能力，这可能导致在执行日常生活任务时出现问题。但是，关于视网膜疾病改变对比编码改变的特定方式相对较少。为了解决这种不足，提出了四个不同的项目，这些项目是一个共同主题，以评估视网膜炎色素（RP）患者的对比处理中的空间和时间缺陷，这是一组夜盲，遗传性视网膜变性，是成人失明的最常见遗传原因。同时对视觉正常个体中对比度编码进行编码的研究将为正常视觉系统内的视觉处理的潜在机制提供新的见解。具体目的是：（1）解决RP患者的亮度对比检测缺陷与推断的巨细胞和副细胞途径内的亮度对比检测缺陷之间的明显矛盾； （2）定义用于评估视网膜变性中字母对比敏感性和视力敏锐度的最佳对象空间频率； （3）确定RP中L型驱动的闪烁电图（ERG）的相位滞后的视网膜起源和一般性； （4）表征在视觉正常个体和患有RP患者的闪烁ERG中同步期的性质，以阐明基本机制的性质。这些目标将通过新颖和创新的心理物理和ERG技术来解决，该技术适用于从伊利诺伊大学研究中心的伊利诺伊大学研究中心的AUSPICES上获得1,400多名RP的人群招募的人，以及对具有正常视力的年龄相等的个人。最近的突破已经提高了我们对视觉视网膜变性的分子遗传基础的理解，并且正在研究治疗干预措施的潜在策略，但是评估视觉系统功能完整性的标准临床方法已知。本应用中提出的研究旨在提供视网膜退化患者的视觉功能障碍的新方法，以识别更多均匀的患者亚组，以纳入临床试验中，并评估潜在治疗策略的结果。