Optical Imaging of Baseline Blood Flow and Oxygenation During Stroke

中风期间基线血流和氧合的光学成像

• 批准号: 8474751
• 负责人: Andrew K Dunn
• 金额: $ 29.59万
• 依托单位: UNIVERSITY OF TEXAS AT AUSTIN
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2015-04-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8474751
• 关键词: Acute; Adoption; Animal Model; Animals; Behavioral; Blood flow; Cerebrovascular Circulation; Cerebrum; Chronic; Development; Devices; Elements; Goals; Hemoglobin; Image; Imaging Techniques; Imaging technology; Ischemia; Knowledge; Lasers; Maps; Measurement; Measures; Methods; Microcirculation; Morphologic artifacts; Nitric Oxide; Optical Instrument; Optics; Outcome; Oxygen; Patients; Physiological; Physiology; Relative (related person); Resolution; Speed; Stroke; Techniques; Technology; Thick; Tissues; acute stroke; angiogenesis; base; chronic stroke; cranium; design; detector; digital; hemodynamics; imaging modality; in vivo; instrument; instrumentation; neuroprotection; optical imaging; phosphorescence; public health relevance; research study; stroke therapy; success

DESCRIPTION (provided by applicant): Many stroke therapies currently under development in animal models target the cerebral microcirculation. As a result, quantitative in vivo measurement of hemodynamic parameters such as blood flow and oxygenation are critical needs in these studies. Although several optical and MR based techniques are widely used in such experimental stroke studies, the existing techniques suffer from significant limitations. In particular, most techniques are limited to measurement of the relative change of a single hemodynamic parameter within a single animal during a single measurement period. As a result these methods cannot be used to determine absolute blood flow or oxygenation, or to assess chronic hemodynamic changes, which can hinder efforts to evaluate stroke therapies that attempt to gradually restore blood flow and oxygen delivery to ischemic tissue by stimulating angiogenesis or by enhancing nitric oxide synthesis. Therefore, the overall goal of this proposal is to develop an optical instrument capable of imaging baseline cerebral hemodynamics (blood flow and oxygenation) and to use this instrument to quantify the acute and chronic hemodynamic changes that occur following ischemia. To accomplish this goal we will advance two optical imaging techniques that have shown significant promise in stroke studies. In Aim 1 we will advance laser speckle contrast imaging for imaging cerebral blood flow to enable imaging of baseline blood flow levels by developing multi-exposure speckle imaging. Our recent results have demonstrated that multi-exposure speckle imaging is capable of overcoming many of the limitations of traditional single exposure speckle imaging. In Aim 2 we will develop an instrument for high resolution mapping of absolute cortical oxygenation levels by combining a digital micromirror device with phosphorescence quenching measurements. This approach will be combined with the multi-exposure speckle imaging for simultaneous imaging of absolute oxygenation and blood flow. We will then use this instrument to quantify the acute and chronic hemodynamic alterations following stroke in Aim 3. In particular we will map the absolute blood flow and oxygenation levels throughout the ischemic territory and compare the chronic hemodynamics with behavioral and anatomical stroke outcomes.

描述（由申请人提供）：目前正在动物模型中开发的许多中风疗法都以脑微循环为目标。 因此，血流动力学参数（例如血流量和氧合）的体内定量测量是这些研究中的关键需求。 尽管几种基于光学和磁共振的技术广泛用于此类实验性中风研究，但现有技术仍存在很大的局限性。 特别是，大多数技术仅限于测量单个动物内单个测量周期内单个血液动力学参数的相对变化。 因此，这些方法不能用于确定绝对血流或氧合，或评估慢性血流动力学变化，这可能会阻碍评估中风治疗的努力，这些中风治疗试图通过刺激血管生成或增强血管生成来逐渐恢复缺血组织的血流和氧气输送。一氧化氮的合成。 因此，该提案的总体目标是开发一种能够对基线脑血流动力学（血流和氧合）进行成像的光学仪器，并使用该仪器来量化缺血后发生的急性和慢性血流动力学变化。 为了实现这一目标，我们将推进两种光学成像技术，这些技术在中风研究中显示出了巨大的前景。 在目标 1 中，我们将推进用于脑血流成像的激光散斑对比成像，通过开发多重曝光散斑成像来实现基线血流水平的成像。 我们最近的结果表明，多次曝光散斑成像能够克服传统单次曝光散斑成像的许多局限性。 在目标 2 中，我们将开发一种仪器，通过将数字微镜装置与磷光猝灭测量相结合，用于绝对皮质氧合水平的高分辨率绘图。 该方法将与多重曝光散斑成像相结合，以同时对绝对氧合和血流进行成像。 然后，我们将使用该仪器来量化目标 3 中中风后的急性和慢性血流动力学变化。特别是，我们将绘制整个缺血区域的绝对血流和氧合水平，并将慢性血流动力学与行为和解剖学中风结果进行比较。