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: 10470130
• 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 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10470130
• 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.

项目总结