Magnetic Resonance Imaging of Glaucoma

青光眼的磁共振成像

• 批准号: 8925889
• 负责人: Timothy Q. Duong
• 金额: $ 29.3万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8925889
• 关键词: Affect; Age; Age-Months; Air; Anatomy; Area; Axon; Biological Markers; Blindness; Blood Vessels; Blood flow; Carbon Dioxide; Choroid; Chronic; Control Animal; Data; Development; Diabetic Retinopathy; Disease; Dorzolamide; Early Diagnosis; Early treatment; Equilibrium; Evaluation; Eye; Foundations; Functional Imaging; Functional Magnetic Resonance Imaging; Future; Genetic; Glaucoma; Health; Histology; Human; Hypercapnia; Hyperoxia; Hypoxia; Image; Imaging Techniques; Imaging technology; Injury; Ischemia; Knowledge; Laboratories; Magnetic Resonance Imaging; Measurement; Mediating; Modeling; Monitor; Morphologic artifacts; Mus; Nerve Fibers; Optic Disk; Optic Nerve; Outcome; Pathogenesis; Patients; Phase; Physiologic Intraocular Pressure; Physiological; Predisposition; Production; Research; Resolution; Retina; Retinal; Retinal Degeneration; Retinal Diseases; Retinal Ganglion Cells; Risk; Scheme; Specificity; Staging; Stimulus; Therapeutic Intervention; Thick; Time; Tissues; Treatment Protocols; Visual impairment; animal data; aqueous; base; blood oxygen level dependent; blood oxygenation level dependent response; cell injury; clinically relevant; clinically significant; data acquisition; density; efficacy testing; ganglion cell; hemodynamics; improved; insight; male; non-invasive imaging; novel; prevent; relating to nervous system; research study; response; retinal nerve fiber layer; spatiotemporal; treatment effect; visual stimulus

DESCRIPTION (provided by applicant): Glaucoma, a leading cause of irreversible blindness in the world, is characterized by progressive degeneration of the retinal ganglion cells (RGCs), the retinal nerve fiber layer, and the optic nerve. Glaucoma is often associated with elevated intraocular pressure (IOP), and because the increased IOP exerts a compressing force on the blood vessels in the eye, it has long been hypothesized that the RGC damage is caused by mild, but chronic, reduction of basal blood flow and/or blood-flow dysregulation. For many patients, by the time glaucoma is detected in examinations or patients notice vision loss, more than half of the RGCs have already degenerated. The eventual outcome is often blindness. Thus, non-invasive imaging technologies capable of detecting depth-resolved blood flow, oxygenation, and stimulus-evoked hemodynamic changes to evaluate blood flow reduction and dysregulation in the retina and the optic nerve head could enable objective early detection, longitudinal disease staging, and monitoring of therapeutic interventions. Although optically based imaging techniques provide high spatial resolution, they are depth limited which precludes quantitative resolution of retinal, choroidal, and optic nerve blood flow. Our laboratory pioneered the application of multimodal MRI to image high-resolution lamina-specific anatomy, blood flow, oxygenation, and function of the retina without depth limitation. Here we propose: i) to develop a multimodal MRI approach to markedly improve contrast and spatial resolution (35x35x300 �m) without MRI susceptibility artifact by using a 3D balanced Steady State Free Precession (bSSFP) data acquisition scheme, and ii) to apply this approach in an established genetic (DBA/2J) mouse glaucoma model to determine whether MRI can detect glaucomatous changes in early stage and examine a plausible mechanism of glaucoma pathogenesis. We hypothesize that: 1) MRI can provide high resolution, depth-resolved, laminar- specific anatomical, blood flow, and functional images free of susceptibility artifacts; and 2) the pathogenesis of glaucoma is mediated by reduced blood flow and/or blood-flow dysregulation in the early stage, resulting in eventual loss of RGCs by ischemic hypoxia, and, if this is the cause, hyperoxia treatment should halt glaucomatous damage.

描述（由适用提供）：青光眼是世界上不可逆失明的主要原因，其特征是视网膜神经节细胞（RGC），视网膜神经纤维层和视神经的进行性变性。青光眼通常与眼内压（IOP）升高有关，并且由于IOP的增加对眼睛的血管施加了压缩力，因此长期以来一直假设RGC损害是由轻度的，但慢性，慢性，基本的血液流量减少和/或血液流量减少。对于许多患者，在检查中检测到青光眼或患者注意到视力丧失时，超过一半的RGC已经退化。事件结果通常是失明。这是，能够检测深度解决的血流，氧合和刺激的诱发血液动力学变化以评估视网膜和视神经头的血流减少和失调的非侵入性成像技术，可以启用客观的早期检测，纵向疾病分期，并监测较高的基于热干预措施。规定视网膜，脉络膜和视神经血流的定量分辨率。我们的实验室 开创了多模式MRI在图像高分辨率特异性解剖结构，血流，氧合和视网膜功能的情况下的应用。在这里我们提出：i）开发一种多模式MRI方法，以明显改善对比对比度和空间分辨率（35x35x300米），没有MRI敏感性伪像，使用3D均衡稳态自由预测（BSSFP）数据采集方案，ii）是否会在固定的遗传（DBA/DBA）模型中应用此方法，以将这种方法应用于固定的遗传（DBA/DBA）。阶段和检查青光眼发病机理的合理机制。我们假设：1）MRI可以提供高分辨率，深度分辨，层状特异性解剖学，血液流量和功能图像，没有易感性伪影； 2）青光眼的发病机理是通过早期的血液流动和/或血流失调介导的，导致缺血性缺氧的RGC丧失，如果这是原因，这是原因。 高氧治疗应阻止青光眼损伤。