Spectrally optimized, Spatially resolved Poro and Viscoelastic Brain MRE

光谱优化、空间分辨的 Poro 和粘弹性脑 MRE

• 批准号: 8660174
• 负责人: KEITH D. PAULSEN
• 金额: $ 35.99万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-30 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8660174
• 关键词: Alzheimer' s Disease; Animal Model; Animals; Biological Models; Blood; Blood Vessels; Brain; Brain imaging; Canis familiaris; Cerebrovascular system; Clinical; Data; Demyelinations; Development; Edema; Evaluation; Evaluation Studies; Family Felidae; Family suidae; Frequencies; Head; Human; Hydrocephalus; Image; Imaging Techniques; Intracranial Hypertension; Liquid substance; Magnetic Resonance Elastography; Maps; Mechanics; Methods; Modeling; Motion; Multiple Sclerosis; Neurologic; Performance; Property; Radiation; Recovery; Relative (related person); Reporting; Resolution; Series; Study Subject; System; Techniques; Tissues; Venous; base; cerebrovascular; comparative; design; image reconstruction; imaging modality; in vivo; innovation; interest; interstitial; nervous system disorder; novel strategies; phantom model; pressure; public health relevance; research study; response; vibration

DESCRIPTION (provided by applicant): We have established an innovative approach to brain magnetic resonance elastography (MRE) based on encoding of endogenous low frequency (~1Hz) motion resulting from blood pulsation through the cerebrovascular system that is reconstructed with a poroelastic mechanical model to produce three- dimensional (3D), spatially-resolved mechanical and hydrodynamical property images. Our poroelastic MRE (pMRE) methods have produced promising preliminary data in phantoms, animals, and humans. In parallel, we have advanced substantially our viscoelastic MRE (vMRE) methods based on external high frequency (50- 100Hz) actuation, and preliminary data from our latest vMRE studies in phantoms, animals and humans are also very impressive because of the spatially-resolved mechanical property information that can be obtained. Indeed, we have evidence to suggest that vMRE and pMRE are complementary - namely that vMRE is the method of choice at externally-actuated high frequencies where the viscous damping effects of brain parenchyma are more dominant, whereas pMRE is the best choice at intrinsically-actuated low frequencies where the hydrodynamic fluid effects become more important. Our overall objective in this project is to unify and optimize our pMRE and vMRE methods in order to evaluate them across the frequency spectrum of interest (~1-100Hz) in a series of phantom and animal model systems which will identify the conditions under which they provide superior, comparable and/or complementary images and data. Specifically, we will (1) develop a unified framework and platform through which we will advance and optimize our pMRE and vMRE image reconstruction methods, (2) use actuation and phantom systems for comparative evaluations across the frequency range of interest, and (3) complete experiments in three large animal models with controllable parameters and experimental conditions under which comparative evaluations will occur in vivo. Evidence already exists to support the potential of brain MRE to inform clinical identification and management of multiple neurological disorders. We hypothesize that brain MRE has much more to offer - specifically, that 3D, spectrally-optimized, spatially-resolved maps of tissue mechanical and hydrodynamical properties should be the standard - not the whole/regional brain mechanical property averages that have largely been reported to date. External and intrinsic brain actuation both have merit, as do pMRE and vMRE; hence, a focused and sustained effort to optimize, evaluate and compare these approaches across the available frequency range is needed to identify the methods of choice under selected and prevailing conditions of interest.

描述（由申请人提供）：我们已经建立了一种创新的脑磁共振弹性成像（MRE）方法，该方法基于对脑血管系统中血液脉动产生的内源性低频（~1Hz）运动进行编码，并使用多孔弹性力学模型进行重建，以产生三维（3D）、空间分辨的机械和流体动力学特性图像。我们的多孔弹性 MRE (pMRE) 方法已经在模型、动物和人类中产生了有希望的初步数据。与此同时，我们还大幅推进了基于外部高频（50-100Hz）驱动的粘弹性MRE（vMRE）方法，并且我们在模型、动物和人类中最新的vMRE研究的初步数据也非常令人印象深刻，因为可以获得空间分辨的机械属性信息。事实上，我们有证据表明 vMRE 和 pMRE 是互补的，即 vMRE 是外部驱动高频下的首选方法，此时脑实质的粘性阻尼效应更为占主导，而 pMRE 是内部驱动低频下的最佳选择，此时流体动力流体效应变得更为重要。我们在该项目中的总体目标是统一和优化我们的 pMRE 和 vMRE 方法，以便在一系列体模和动物模型系统中的感兴趣的频谱（~1-100Hz）上对它们进行评估，从而确定它们提供优质、可比较和/或补充图像和数据的条件。具体来说，我们将（1）开发一个统一的框架和平台，通过它我们将推进和优化我们的 pMRE 和 vMRE 图像重建方法，（2）使用驱动和体模系统在感兴趣的频率范围内进行比较评估，以及（3）在具有可控参数和实验条件的三个大型动物模型中完成实验，在体内进行比较评估。已有证据支持脑部 MRE 为多种神经系统疾病的临床识别和管理提供信息的潜力。我们假设大脑 MRE 可以提供更多功能 - 具体来说，组织机械和流体动力学特性的 3D、光谱优化、空间分辨图应该成为标准 - 而不是迄今为止已广泛报道的整个/区域大脑机械特性平均值。外部和内部大脑驱动都有优点，pMRE 和 vMRE 也一样；因此，需要集中和持续地努力在可用频率范围内优化、评估和比较这些方法，以确定在选定和普遍感兴趣的条件下选择的方法。