Human Brain Interferometers for Better Blood Flow Monitoring

人脑干涉仪可更好地监测血流

基本信息

批准号：
10541218
负责人：
Vivek Jay Srinivasan
金额：
$ 59.48万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-04-13 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10541218
关键词：
Address Adult Anatomy Blood flow Brain Brain Injuries Brain region Cardiac Surgery procedures Caring Cerebrovascular Circulation Cerebrum Clinical Research Detection Diffuse Dimensions Discrimination Erythrocytes Face Fiber Flowmetry Goals Head Homeostasis Human Hypoxia Individual Industry Injury Interferometry Intervention Intracranial Pressure Light Link Magnetic Resonance Imaging Measurement Measures Methods Modality Monitor Morphologic artifacts Motion Noise Observational Study Optical Instrument Optics Patients Penetration Performance Perfusion Photons Physics Physiological Predisposition Property Research Resolution Scalp structure Source Specificity Spectrum Analysis Speed Stroke Surface TBI Patients Technology Testing Time Tissues Transcranial Doppler Ultrasonography Traumatic Brain Injury X-Ray Computed Tomography blood flow measurement cerebrovascular health cost detector follow-up improved in vivo indexing innovation instrument multimodality non-invasive monitor parallelization photon-counting detector portability quantum sensor tool

项目摘要

Abstract: A major goal in the management of traumatic brain injury (TBI) is to optimize cerebral blood flow (CBF) over the days to weeks following injury. Yet, there is currently no well-established, non-invasive method to continuously monitor CBF in adults. Though diffuse optical flowmetry (DOF) methods for monitoring CBF based on dynamic scattering of near-infrared (NIR) light are used in research, these methods suffer from fundamental limitations. First, they require costly photon counting, which strictly constrains achievable speed, brain specificity, and brain coverage. Second, they lack depth discrimination, leading to contamination from blood flow in superficial tissues. Third, they require assumptions about optical properties, which can vary between individuals or across brain regions. Fourth, they are sensitive to noise from ambient light. To address these limitations, we introduce interferometry to human diffuse optics, creating a new class of NIR light-based monitoring tools, called interferometric Diffuse Optical Spectroscopy (iDOS). First, we show that with interferometry, a CMOS sensor can replace photon counting and parallelize measurements of weak diffuse light fluctuations that reveal CBF. This advance improves light throughput-to-cost ratio by ~100x. We can thus take more measurements (improving brain coverage) with larger source collector separations (improving brain specificity). Then, we show that by rapidly tuning the light source wavelength, we also achieve time-of-flight (TOF) resolution. This extra TOF dimension better distinguishes brain from superficial tissue, and also provides estimates of optical properties, improving quantification. Finally, interferometric methods are essentially unaffected by ambient light. Building on our promising results in adult humans, we will develop, optimize, and validate iDOS for quantitative, rapid, and robust CBF monitoring. We will identify the advantages and weaknesses of iDOS relative to conventional methods. Finally, we will perform observational CBF monitoring in severe TBI patients in the neurointensive care unit (neuro-ICU), testing the ability of our non-invasive CBF measurements to predict periods of hypoxia.

抽象的：治疗创伤性脑损伤 (TBI) 的一个主要目标是优化脑血流 (CBF) 受伤后几天到几周。然而，目前还没有成熟的、非侵入性的方法来持续监测成人 CBF。通过基于动态的漫射光流计 (DOF) 方法监测 CBF 研究中使用了近红外 (NIR) 光的散射，但这些方法存在根本性的局限性。首先，它们需要昂贵的光子计数，这严格限制了可实现的速度、大脑特异性和大脑覆盖范围。其次，它们缺乏深度辨别能力，导致浅表组织血流污染。第三，它们需要对光学特性的假设，这些假设可能因个体或不同大脑而异地区。第四，它们对环境光的噪音很敏感。为了解决这些限制，我们将干涉测量法引入人体漫射光学器件，创建了一类新的近红外光谱基于光的监测工具，称为干涉漫光谱 (iDOS)。首先，我们证明干涉测量法，CMOS 传感器可以取代光子计数并并行测量弱漫射光揭示 CBF 的波动。这一进步将光通量成本比提高了约 100 倍。因此我们可以采取更多的测量（改善大脑覆盖）和更大的源收集器间隔（改善大脑特异性）。然后，我们表明，通过快速调整光源波长，我们还实现了飞行时间（TOF）分辨率。这个额外的 TOF 维度可以更好地区分大脑和浅表组织，并且还提供光学特性的估计，改进量化。最后，干涉测量方法本质上是不受环境光的影响。基于我们在成年人身上取得的有希望的结果，我们将开发、优化和验证 iDOS，以进行定量、快速、稳健的 CBF 监测。我们将确定 iDOS 相对于其他操作系统的优点和缺点常规方法。最后，我们将对严重 TBI 患者进行观察性 CBF 监测神经重症监护病房 (neuro-ICU)，测试我们的无创 CBF 测量预测经期的能力缺氧。