Functional Testing for Glaucoma

青光眼功能测试

• 批准号: 8186451
• 负责人: Stuart Gardiner
• 金额: $ 36.45万
• 依托单位: LEGACY EMANUEL HOSPITAL AND HEALTH CENTER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8186451
• 关键词: Algorithms; Area; Blindness; Clinical; Contrast Sensitivity; Data; Data Collection; Data Set; Defect; Detection; Disease; Frequencies; Functional disorder; Future; Glaucoma; Laboratories; Location; Measurement; Measures; Noise; Optic Disk; Patients; Perimetry; Probability; Quality of life; Reporting; Research; Retinal Ganglion Cells; Source; Stimulus; Structure; Techniques; Testing; Time; Vision; Visual Fields; Visual system structure; Work; base; central visual field; clinical practice; cost; design; follow-up; functional status; glaucoma test; improved; indexing; instrument; luminance; next generation; novel; prevent; prognostic; response

DESCRIPTION (provided by applicant): Glaucoma is a leading cause of blindness both in the US and worldwide. The long-term purpose of this project is to improve functional testing in glaucoma. Assessment and follow-up of patients currently relies on automated perimetry to provide functional testing of the visual field. However, the ability to assess progression and/or response to treatment using perimetry is hampered by high variability, especially in areas of moderate or severe glaucomatous damage. Recent findings by our laboratory and others have advanced our understanding of perimetry by challenging key assumptions about the test. This proposal aims to use these advances to explain and reduce the test variability. This will improve the accuracy, efficiency and utility of current functional testing, giving immediate impact in both research and clinical settings, and laying groundwork for the next generation of instruments and algorithms. The first Specific Aim is to produce an accurate and physiologically justified measure of the Effective Dynamic Range (EDR) of perimetry. It is postulated that the very high contrast stimuli used by perimetry in glaucomatous defects saturate the response of the visual system. The resultant nonlinearity in the contrast-response function would cause the detection probability to asymptote below 100%, explaining the high variability in sensitivities in damaged areas. The limit of the EDR will be defined as the contrast beyond which response linearity cannot be assumed. This will be measured by collecting frequency-of-seeing curves in subjects with moderate or advanced glaucoma. The same technique will be used to determine whether the EDR is extended by use of an increased stimulus size. The second Specific Aim is to derive and test a spatial filter to reduce the variability. This will be the first filter to be based both on sensitivities at other locations in the visual field and on the structure of the optic nerve head. The third Specific Aim is to assess the potential utility of using a linear scale for sensitivity, rather than the current logarithmic decibel scale. First, an efficient linear-scaled thresholding algorithm will be derived and tested, to determine whether it will reduce variability both between tests and in the structure-function relation. Second, linear-scaled global indices of the central visual field will be examined, to determine whether they offer improved prognostic value compared with current decibel-scaled indices when assessing progression. The three aims are complementary. It is anticipated that by combining these aims, variability in perimetry will be better understood, and significantly reduced. Such an improvement in a test as commonly performed as perimetry will significantly impact future clinical practice. PUBLIC HEALTH RELEVANCE: This project aims to explain and reduce the variability observed in functional testing of the visual field in patients with glaucoma. This will allow earlier and more accurate assessment of a patient's current status and response to treatment. It will improve the ability to design an appropriate and cost-efficient personalized management strategy to preserve vision, with the aim of maintaining a patient's quality of life.

描述（由申请人提供）：青光眼在美国和世界范围内都是致盲的主要原因。该项目的长期目的是改进青光眼的功能检测。目前，患者的评估和随访依赖于自动视距测量来提供视野的功能测试。然而，评估进展和/或治疗反应的能力受到高度可变性的阻碍，特别是在中度或重度青光眼损伤的区域。我们的实验室和其他实验室最近的发现通过挑战有关测试的关键假设，提高了我们对视界的理解。本建议旨在利用这些进步来解释和减少测试的可变性。这将提高当前功能检测的准确性、效率和实用性，对研究和临床环境产生直接影响，并为下一代仪器和算法奠定基础。第一个具体目标是产生一个准确的和生理合理的测量有效动态范围（EDR）的视野。这是假设，非常高的对比度刺激使用的验光在青光眼缺陷饱和的视觉系统的反应。对比响应函数所产生的非线性将导致检测概率渐近线低于100%，这解释了受损区域灵敏度的高变异性。EDR的极限将被定义为超过此对比度，响应线性就不能被假设。这将通过收集中度或晚期青光眼患者的视频曲线来测量。同样的技术将用于确定EDR是否通过增加刺激规模而得到延长。第二个具体目标是推导和测试一个空间滤波器，以减少可变性。这将是第一个既基于视野中其他位置的敏感度又基于视神经头结构的过滤器。第三个具体目标是评估使用线性刻度来衡量灵敏度的潜在效用，而不是目前的对数分贝刻度。首先，将推导和测试一种有效的线性缩放阈值算法，以确定它是否会减少测试之间和结构-功能关系中的可变性。其次，将检查中央视野的线性尺度全局指数，以确定在评估进展时，与当前的分贝尺度指数相比，它们是否提供更好的预后价值。这三个目标是互补的。预计通过结合这些目标，可以更好地理解并显著减少周边测量的变异性。这样一种检测方法的改进，就像验光术一样，将对未来的临床实践产生重大影响。