Visible-light OCT angiography, velocimetry, and oximetry for characterizing retinal vascular alterations in glaucoma

可见光 OCT 血管造影、测速和血氧测定法用于表征青光眼视网膜血管改变

• 批准号: 10232055
• 负责人: Yali Jia
• 金额: $ 50.07万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10232055
• 关键词: 3-Dimensional; Abbreviations; Acute; Address; Affect; Angiography; Architecture; Arteries; Attention; Axon; Blindness; Blood Circulation; Blood Vessels; Blood capillaries; Blood flow; Computer software; Defect; Detection; Development; Diagnosis; Early identification; Event; Eye; Glaucoma; Glossary; Goals; Homeostasis; Impairment; Injury; Intraocular pressure test; Lasers; Lateral; Lead; Lighting; Machine Learning; Measurement; Measures; Methods; Modeling; Noise; Optic Nerve; Optic Nerve Injuries; Optic Nerve Transections; Optical Coherence Tomography; Oxygen; Oxygen saturation measurement; Patients; Performance; Physiologic Intraocular Pressure; Predisposition; Process; Progressive Disease; Rattus; Resolution; Retina; Retinal Ganglion Cells; Rodent Model; Role; Scanning; Signal Transduction; Speed; Structure; Structure of central vein of the retina; System; Technology; Testing; Time; Tissues; Vascular Diseases; Veins; Velocimetries; Visible Radiation; Vision; Visual impairment; attenuation; automated segmentation; central retinal artery; data acquisition; deep learning; density; image processing; improved; in vivo; innovation; insight; metabolic rate; new technology; novel strategies; preservation; pressure; prototype; response; retina blood vessel structure; retina circulation; retinal imaging; retinal ischemia; traditional therapy; vascular factor

Project Summary Glaucoma damage to the optic nerve and impairment of vision are progressive and irreversible. Understanding mechanisms of glaucomatous injury will help to develop new approaches for treatments that can be used along with traditional therapies that lower intraocular pressure (IOP). Recent developments in optical coherence tomography (OCT) angiography have brought increased attention to the role of the inner retinal circulation in glaucoma. To improve our understanding of retinal vascular alterations in glaucoma, we can take advantage of recent developments in visible-light OCT (vis-OCT) to characterize simultaneously tissue structure, vessel density, blood flow and oxygenation. The goal of this project is to further advance vis-OCT by attaining capillary-level measurements, test the value of measuring their local alterations as early indicators of glaucoma and glaucomatous progression and use this to evaluate impaired retinal autoregulation from retinal ganglion cell (RGC) loss as a potential cause of increased susceptibility in advanced glaucoma. In Specific Aim 1 we will develop high-speed, high-sensitivity, high-resolution vis-OCT. The speed will be double that of the current system. A more stable supercontinuum laser will be used to improve system sensitivity, and a tighter focus will be used to improve lateral resolution. This will enable complete detection of capillaries that may be vulnerable to vascular dysfunction. Specific Aim 2 will develop quantitative OCT angiography, velocimetry and oximetry in capillaries as well as arteries and veins. Building on the high-resolution, high-contrast scans acquired in Aim 1, we will use machine learning to segment capillary plexuses, and advanced image processing to extract capillary architecture. Aided by this capillary architecture, we will automatically measure blood flow and oxygenation in capillary segments and incorporate them into a real-time platform. Specific Aim 3 will use this system to demonstrate that acute loss of RGCs, produced by optic nerve transection, alters retinal capillary plexus density, oximetry and velocimetry over time and that these changes precede altered oximetry and flow in larger retinal vessels. We will also show that loss of RGCs impairs the autoregulatory response to acute IOP challenge. In Specific Aim 4, we will demonstrate that optic nerve injury in a model of controlled, elevated IOP produces early alterations in capillary velocimetry, oximetry and autoregulation, show that they are more persistent with advanced injury, and demonstrate the pathophysiologic consequences of these observations. Successful development of this new technology will improve methods of early glaucoma diagnosis and detection of progression. Better understanding of retinal vascular factors that lead to increased susceptibility in advanced glaucoma will lead to improved treatments for these highly vulnerable patients.

项目概要 青光眼对视神经的损害和视力损害是进行性且不可逆转的。理解 青光眼损伤的机制将有助于开发新的治疗方法，可与 与降低眼内压（IOP）的传统疗法。光学相干的最新进展 断层扫描（OCT）血管造影使人们越来越关注视网膜内循环在 青光眼。为了提高我们对青光眼视网膜血管改变的了解，我们可以利用 可见光 OCT (vis-OCT) 的最新进展可同时表征组织结构、血管 密度、血流量和氧合。该项目的目标是通过实现 毛细血管水平测量，测试测量其局部变化作为青光眼早期指标的价值 和青光眼进展，并用它来评估视网膜神经节受损的视网膜自动调节 细胞（RGC）损失是晚期青光眼易感性增加的潜在原因。 在具体目标 1 中，我们将开发高速、高灵敏度、高分辨率的 vis-OCT。速度将是 是当前系统的两倍。将使用更稳定的超连续谱激光器来改进系统 灵敏度和更紧的焦点将用于提高横向分辨率。这将能够完整检测 毛细血管可能容易出现血管功能障碍。 具体目标 2 将开发毛细血管定量 OCT 血管造影、测速和血氧测定 动脉和静脉。基于目标 1 中获得的高分辨率、高对比度扫描，我们将使用机器 学习分割毛细血管丛，以及先进的图像处理来提取毛细血管结构。辅助 通过这种毛细血管结构，我们将自动测量毛细血管段的血流量和氧合 并将它们整合到实时平台中。 具体目标 3 将使用该系统来证明由视神经产生的 RGC 的急性损失 横切，随着时间的推移改变视网膜毛细血管丛密度、血氧测定和测速，并且这些变化 先于较大视网膜血管中的血氧测定和血流改变。我们还将证明 RGC 的损失会损害 对急性眼压挑战的自动调节反应。 在具体目标 4 中，我们将证明在受控、升高的 IOP 模型中视神经损伤会产生 毛细血管测速、血氧测定和自动调节的早期变化表明，它们更持久 晚期损伤，并证明这些观察结果的病理生理学后果。 这项新技术的成功开发将改善青光眼的早期诊断和治疗方法 检测进展。更好地了解导致易感性增加的视网膜血管因素 晚期青光眼将为这些高度脆弱的患者带来更好的治疗。