Interferometric Speckle Visibility Spectroscopy for Brain Activity Associated Cerebral Blood Flow Monitoring

用于脑活动相关脑血流监测的干涉散斑可见光谱

• 批准号: 10294139
• 负责人: CHANGHUEI YANG
• 金额: $ 28.78万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-30 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10294139
• 关键词: Address; Blood; Blood flow; Brain; Categories; Cerebrovascular Circulation; Clinical; Data; Detection; Diffuse; Hemoglobin; Human; Light; Location; Magnetic Resonance Imaging; Measurement; Measures; Metabolic; Methods; Monitor; Motor; Motor Cortex; Near-Infrared Spectroscopy; Optical Methods; Optics; Output; Oxygen; Pattern; Positron-Emission Tomography; Radiation; Research; Sampling; Sensitivity and Specificity; Signal Transduction; Site; Spectrum Analysis; Speed; Surface; System; Technology; Testing; Time; Ultrasonography; Update; Visual; Visual Cortex; absorption; advanced system; base; blood flow measurement; blood oxygen level dependent; cost; density; design; diffuse optical tomography; improved; instrument; light weight; neurovascular; novel; portability; prototype; response; scale up; temporal measurement; transmission process; uptake

Abstract Optical monitoring of brain activities is intrinsically associated with a range of operational advantages: a. non-ionizing and safe radiation, b. simple and relatively lightweight apparatus, c. readily available commercial optical advanced systems that can be cross adapted for our usage. While the prevalent optical brain monitoring methods are based on measuring blood oxygenation level dependent (BOLD) signal associated with the absorption spectral shift of blood to oxygen level changes, optical methods based on measuring cerebral blood flow (CBF) signal associated with scattering dynamics that scale with the blood flow in the brain may provide a promising alternative with certain advantages. Some of these advantages include: 1) Provide neurovascular information that is complementary to BOLD information – the combination of which can reveal a more complete picture of the neurovascular interactions. For example, the combination of BOLD and CBF measurements may be used to compute metabolic oxygen uptake rate in the brain. 2) As CBF measurements do not depend on the absorption spectrum of hemoglobin, there is a potential that CBF methods can penetrate deeper into the brain by using longer wavelengths. 3) Optical CBF methods are relatively simple to implement. We envision that a high-density full brain surface coverage CBF instrument can be implemented in a portable fashion. For this R21 project, we propose to develop and evaluate a novel CBF measurement method, known as interferometric speckle visibility spectroscopy (iSVS), for the task of high sensitivity and multi-point brain monitoring. The iSVS method is substantially different from the current optical CBF method of choice – diffuse correlation spectroscopy (DCS). Whereas DCS requires sampling of the speckle fluctuations at a rate much faster than the decorrelation time (typically ~ 100 microseconds), iSVS can perform measurements at a much slower rate of ~ 100 Hz and still provide superior measurement SNR by exploiting the multiple pixels available on commercial cameras. We propose to implement and test a parallel CBF monitoring prototype that can monitor 50 locations simultaneously with an update rate of 100 Hz. We will then compare sensitivity and specificity of the developed iSVS to relative CBF changes evoked by simple motor and visual tasks in the primary motor and visual cortex of the human brain. If successful, the technology will fill a vital measurement gap that existing optical, MRI, ultrasound and PET methods have not been able to address.

抽象的 对大脑活动的光学监测与一系列操作优势本质上相关： 一个。非电离和安全辐射，b。简单且相对轻巧的设备，c。随时可用 可以用于使用我们的使用的商业光学高级系统。而流行的光学 大脑监测方法基于测量血液氧合水平依赖性（粗体）信号 与血液向氧气水平变化的抽象光谱相关，基于光学方法 测量与散射动力学相关的脑血流（CBF）信号，该动力学随着血流而扩展 在大脑中，可以提供某些优势的承诺替代方案。其中一些优点包括： 1）提供完整的大胆信息的神经血管信息 - 该信息的组合 可以揭示更完整的神经血管相互作用的图片。例如，大胆的组合 CBF测量值可用于计算大脑中的代谢氧摄取速率。 2）作为CBF 测量不取决于血红蛋白的抽象光谱，而CBF的潜力 方法可以使用更长的波长深入大脑。 3）光学CBF方法是 相对简单实现。我们设想高密度的全脑表面覆盖CBF仪器 可以以便携式方式实现。 对于这个R21项目，我们建议开发和评估一种新颖的CBF测量方法，即已知 作为干涉式斑点可见度光谱（ISV），用于高灵敏度和多点大脑的任务 监视。 ISVS方法与当前的光学CBF选择方法大不相同 - 分散 相关光谱（DC）。而DC需要以多数的速度进行斑点波动采样 ISV比去相关时间（通常约100微秒）快的速度更快，可以在很多方面进行测量 〜100 Hz的速度较慢，并且通过利用可用的多个像素来提供出色的测量SNR 在商用摄像机上。 我们建议实现和测试可以监视50个位置的平行CBF监视原型 同样，更新速率为100 Hz。然后，我们将比较开发的灵敏度和特异性 ISV与主电动机和视觉皮层中的简单电机和视觉任务引起的相对CBF变化 人类大脑。如果成功，该技术将填补现有光学MRI的重要测量空白 超声和宠物方法无法解决。