Massively parallel high-speed 3D functional photoacoustic computed tomography of the adult human brain

成人大脑的大规模并行高速 3D 功能光声计算机断层扫描

• 批准号: 10470400
• 负责人: Danny JJ WANG
• 金额: $ 131.04万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-08 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10470400
• 关键词: 3-Dimensional; Acoustics; Address; Adult; Algorithms; Atlases; Attenuated; BRAIN initiative; Back; Blood Vessels; Blood flow; Brain; Brain imaging; Breast; Complement; Data; Dependence; Detection; Development; Diffusion; Doppler Effect; Electric Stimulation; Electronics; Elements; Environment; Functional Imaging; Functional Magnetic Resonance Imaging; Goals; Head; Hemoglobin; High Resolution Computed Tomography; Human; Image; Imaging Device; Imaging technology; Light; Magnetic Resonance Imaging; Maintenance; Maps; Methods; Microscopic; Modality; Modeling; Mus; Newborn Infant; Noise; Organ; Oxyhemoglobin; Positron-Emission Tomography; Process; Radioactive Tracers; Rattus; Resolution; Rest; Rodent; Running; Sampling; Signal Transduction; Site; Speed; Statistical Data Interpretation; Structure of fontanel of skull; Surface; System; Techniques; Technology; Thalamic structure; Thick; Time; Tissues; Translating; Ultrasonic Transducer; Ultrasonic wave; Ultrasonics; Variant; Vibrissae; X-Ray Computed Tomography; attenuation; base; blood oxygen level dependent; cost; cranium; diffuse optical tomography; frontier; functional near infrared spectroscopy; hemodynamics; human imaging; human subject; image reconstruction; imaging capabilities; imaging modality; imaging platform; in vivo; metabolic imaging; next generation; novel; novel strategies; operation; photoacoustic imaging; portability; public health relevance; reconstruction; recruit; relating to nervous system; response; spatiotemporal; success; temporal measurement; ultrasound

ABSTRACT (30 Lines) The BRAIN initiative (RFA-EB-19-002) has called for the development of entirely new or next-generation noninvasive human brain imaging tools and methods that will lead to transformative advances in our understanding of the human brain. Functional MRI (fMRI) at ultrahigh fields has made tremendous improvements in spatiotemporal resolution, allowing brain function to be studied on the level of cortical layers and columns. However, fMRI is generally considered to have a low sensitivity and strong tissue background for detection of function. Positron emission tomography provides powerful metabolic imaging through radioactive tracers but suffers low spatial resolution, as is diffuse optical tomography despite its advantages in speed, cost, and portability. Ultrasound-only imaging cannot image adult human brains because the ultrasonic waves are attenuated and aberrated twice by the skull due to the round-trip propagation. To address these issues, we propose to develop 3D photoacoustic computed tomography (PACT) for fast and ultrafast large-scale neural activity imaging in human brains. PACT is especially well suited for detecting hemodynamic changes related to neural activities. It offers comparable spatial resolution but can be made much faster than fMRI. It is directly sensitive to both oxy- and deoxy-hemoglobin linearly with a low tissue background. Other potential benefits of PACT over fMRI include open imaging platforms, minimal site requirements, quiet and bedside operation, magnet-free environment, and low system maintenance. In the last two decades, we have developed photoacoustic technology at multiple spatial scales ranging from microscopic (subcellular and cellular) to macroscopic (whole rodent, whole human breast, ex vivo adult human skull, and preliminary single-channel 2D and 64-channel 3D in vivo adult human brain) imaging. We have revealed hemodynamic response in the rodent brain to whisker or electrical stimulation and mapped the resting- state functional connectivity of the rat brain in the deep thalamic region. We have also developed sophisticated numerical methods for simulating photoacoustic wave propagation in heterogeneous media and developed frameworks for image reconstruction in acoustically heterogeneous media. Further, we have successfully demonstrated ex vivo PACT through adult human skulls and acquired preliminary images of human heads in vivo. We propose to translate these advances in PACT to human brain imaging through two specific aims: Aim 1: Develop massively parallel high-speed 3D PACT for in vivo fast and ultrafast functional human brain imaging. Aim 2: Validate functional PACT in adult humans in vivo by comparing with ultrahigh-field 7 T fMRI.

摘要（30 行） BRAIN 计划 (RFA-EB-19-002) 呼吁开发全新或下一代 非侵入性人脑成像工具和方法将导致我们的革命性进步 对人类大脑的了解。超高场功能磁共振成像 (fMRI) 取得了巨大进步 时空分辨率，允许在皮质层和柱的水平上研究大脑功能。 然而，fMRI 通常被认为灵敏度较低且组织背景较强，无法检测 功能。正电子发射断层扫描通过放射性示踪剂提供强大的代谢成像，但 与漫射光学断层扫描一样，尽管其在速度、成本和成像方面具有优势，但其空间分辨率较低。 可移植性。仅超声波成像无法对成人大脑进行成像，因为超声波是 由于往返传播，头骨衰减和畸变两次。 为了解决这些问题，我们建议开发 3D 光声计算机断层扫描 (PACT)，以实现快速 以及人脑中的超快大规模神经活动成像。 PACT 特别适合检测 与神经活动相关的血流动力学变化。它提供了可比的空间分辨率，但可以做得更多 比功能磁共振成像更快。它对氧合血红蛋白和脱氧血红蛋白呈线性直接敏感，组织背景较低。 与 fMRI 相比，PACT 的其他潜在优势包括开放的成像平台、最小的场地要求、安静和 床边操作、无磁环境、系统维护成本低。 在过去的二十年中，我们开发了多个空间尺度的光声技术，从 微观（亚细胞和细胞）到宏观（整个啮齿动物、整个人类乳房、离体成人 头骨，以及初步的单通道 2D 和 64 通道 3D 体内成人大脑）成像。我们有 揭示了啮齿动物大脑对胡须或电刺激的血流动力学反应，并绘制了静息- 状态大鼠大脑丘脑深部区域的功能连接。我们还开发了先进的 模拟异质介质中光声波传播的数值方法并开发 声学异构媒体中的图像重建框架。此外，我们还成功地 通过成人头骨展示了离体 PACT 并获得了人类头部的初步图像 体内。我们建议通过两个具体目标将 PACT 的这些进展转化为人脑成像： 目标 1：为体内快速和超快功能人脑开发大规模并行高速 3D PACT 成像。 目标 2：通过与超高场 7 T fMRI 进行比较，在成年人体内验证 PACT 的功能。