New Method for Retinal Imaging

视网膜成像的新方法

• 批准号: 6672439
• 负责人: ALAN D MARMORSTEIN
• 金额: $ 15.1万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-07 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6672439
• 关键词: aging; bioengineering /biomedical engineering; bioimaging /biomedical imaging; biomedical equipment development; eye; eye disorder diagnosis; eye fundus photography; fluorescence; human tissue; macular degeneration; patient oriented research; postmortem; retinal pigment epithelium; retinography

DESCRIPTION (provided by applicant): Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the western world affecting nearly 30% of those over the age of 75. The only accepted risk factors for AMD are age, race, and smoking. AMD alters the quality of life of those affected by causing a debilitating loss of central vision. Currently diagnosis of AMD at its early stages can be difficult. This has led to problems in the development of drugs to treat the disease since clinical trials must rely on following the slow progression of the disease in individuals that are already demonstrating some loss of visual acuity. We have recently found that Bruch's membrane and sub-retinal pigment epithelium (RPE) deposits characteristic of AMD exhibit a unique autofluorescence spectrum that can be excited with light between 360 and 490nm. When compared with the intensity of autofluorescence elicited from RPE lipofuscin, these emissions were significantly elevated in eyes from donors with AMD versus healthy donor eyes. The change in the ratios of these emissions (Bruch's membrane and sub-RPE deposits vs. lipofuscin) correlating with disease suggests that the same principles that allow quantitative microscopy using fluorescence ratiometry could be applied to fundus photography. The goal of the work outlined in this proposal is to design, build, and test a device for fundus fluorescence ratiometry, and to determine the efficacy of this device in the early diagnosis of retinal lesions that are risk factors for AMD. To accomplish this we will perform a series of 3 specific aims. In the first aim we will modify a standard clinical fundus camera for fundus fluorescence ratiometry. In specific aim 2 we will determine ideal excitation and emission wavelengths for fundus fluorescence ratiometry. This will be accomplished by testing a variety of excitation and emission wavelengths using the modified camera on postmortem human donor eyes. In specific aim 3 we will determine whether fundus fluorescence ratiometry shows promise for the diagnosis of lesions associated with AMD. This will be accomplished using eyes from donors with AMD. Specifically we will test the efficacy of this device in identifying basal deposits. Basal deposits are specific retinal lesions that are not visible during a clinical fundus exam. One form of basal deposit, basal linear deposits, are more common in AMD eyes than age-matched controls. A positive outcome to this study would warrant future clinical trials.

描述(申请人提供)：老年性黄斑变性(AMD)是西方世界不可逆转失明的主要原因，影响到75岁以上人群的近30%。唯一可接受的AMD危险因素是年龄、种族和吸烟。AMD通过导致中心视力的衰弱来改变那些受影响的人的生活质量。目前，AMD的早期诊断可能很困难。这导致了治疗这种疾病的药物的开发出现了问题，因为临床试验必须依赖于跟踪已经表现出一些视力丧失的个人的疾病缓慢发展。我们最近发现，AMD特有的Bruch膜和视网膜下色素上皮(RPE)沉积显示出独特的自体荧光光谱，可以在360至490 nm的光激发下进行激发。与RPE脂褐素激发的自发荧光强度相比，AMD供体眼睛的这些发射显著高于健康供体眼睛。这些与疾病相关的发射物(Bruch膜和RPE下沉积物与脂褐素)比率的变化表明，使用荧光比率计量法进行定量显微镜检查的相同原理也可以应用于眼底照相。这项提案中概述的工作的目标是设计、制造和测试一种眼底荧光比率测量设备，并确定该设备在AMD危险因素视网膜病变早期诊断中的有效性。为了实现这一目标，我们将实现一系列3个具体目标。在第一个目标中，我们将改进用于眼底荧光比率测量的标准临床眼底相机。在具体目标2中，我们将确定眼底荧光比率法的理想激发波长和发射波长。这将通过使用改装后的摄像头在死后的人类供体眼睛上测试各种激发和发射波长来完成。在特定的目标3中，我们将确定眼底荧光比率法是否有希望用于AMD相关病变的诊断。这将通过使用AMD捐赠者的眼睛来实现。具体地说，我们将测试该设备在识别基底沉积方面的有效性。基底沉积物是临床眼底检查中看不到的特殊视网膜病变。基底性沉积的一种形式，即基底线状沉积，在AMD眼中比年龄匹配的对照组更常见。这项研究的积极结果将保证未来的临床试验。