Hybrid TMS/MRI system for regionally tailored causal mapping of human cortical circuits and connectivity

混合 TMS/MRI 系统，用于按区域定制人类皮质回路和连接的因果图谱

• 批准号: 10730783
• 负责人: Berkin Bilgic
• 金额: $ 45.21万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10730783
• 关键词: Acoustics; Amplifiers; Behavior; Benchmarking; Brain; Brain Mapping; Calibration; Cell Density; Cells; Cerebral cortex; Custom; Data; Development; Devices; Diffusion; Diffusion Magnetic Resonance Imaging; Electronics; Elements; Functional Magnetic Resonance Imaging; Geometry; Goals; Head; Heating; Human; Hybrids; Image; Imaging Device; Length; Magnetic Resonance Imaging; Maps; Measurement; Measures; Mechanics; Methods; Microscopic; Motor; Motor Cortex; Neocortex; Nerve Fibers; Neurites; Neuronal Plasticity; Neurons; Neurosciences; Pattern; Performance; Phase; Physiologic pulse; Play; Radial; Resolution; Somatosensory Cortex; Specific qualifier value; Structure; Surface; System; Technology; Testing; Therapeutic; Transcranial magnetic stimulation; data acquisition; density; design; experience; experimental study; feasibility testing; flexibility; human imaging; imaging system; improved; in vivo; millimeter; neocortical; neural; neuroimaging; neuronal cell body; neuroregulation; next generation; non-invasive imaging; novel; prototype; radio frequency; reconstruction; tool

Project Summary. We propose a new coil array that will enable next-generation causal brain mapping with unprecedented flexibility, resolution and precision. The proposed ARES2 hybrid array generates E-fields in the cortex for transcranial mag- netic stimulation (TMS) as well as B-fields for spatial and diffusion encoding applications including high-resolu- tion, high b-value diffusion MRI and fMRI. Multi-channel TMS allows different cortical targets to be probed either sequentially or simultaneously, providing a flexible tool for modulating brain activity that is imaged concurrently with MRI. By virtue of their close proximity to the head, the coil elements will provide a large boost in diffusion MRI encoding in the cortex beyond what is possible with current MRI gradient technology, enabling improved sensitivity to mapping neuronal and dendritic sizes and their distribution following targeted neuromodulation and providing sub-millimeter spatial resolution for BOLD-fMRI in the cortex following stimulation. In Aim1, we will test a 3-channel prototype of the proposed head array, ARES2 (Array for Reception, Encoding, Shimming, and Stimulation) by leveraging our recent developments in MR-compatible transcranial magnetic stimulation (TMS) coils. The coils will be driven by large currents to yield 1000 mT/m max. gradients and high slew rates. The parallel design comprising 48 encoding coils permit B0-shimming capability, while 28 radiofre- quency coils interlaced with the encoding coils provide parallel imaging. Custom drive amplifiers and switching electronics will allow alternation between “stimulation” and “imaging” modes. A comprehensive electronic control system will allow arbitrary waveforms to be played out on all channels in sync with the scanner’s pulse sequence. In Aim2, we will scale the system up to the full 48-ch array. We build a new TMS-compatible 28-ch RF receive array that is mechanically integrated with a TMS probe holder device. The TMS probe holder will allow radial adjustment of the TMS probe to allow it to be placed against the head surface. In Aim3, we will apply the system in vivo to perform next-generation causal brain mapping at submillimeter resolution. We will demonstrate ARES2’s ability to provide regionally specific measures of cell body (soma) and neurite size and density in the motor (M1) and somatosensory cortex (S1). These diffusion MRI experiments will make use of gSlider volumetric diffusion encoding to boost SNR and reach submillimeter resolution. For TMS- fMRI, we will use the 9ch TMS and 48ch MRI gradient system in an interleaved manner for successive stimulation and fMRI recording in M1 and S1.

项目摘要。 我们提出了一种新的线圈阵列，它将以前所未有的灵活性实现下一代因果大脑图谱， 所提出的 ARES2 混合阵列在皮层中产生用于经颅磁力的电场。 网络刺激（TMS）以及用于空间和扩散编码应用的B场，包括高分辨率 高 b 值扩散 MRI 和 fMRI 允许探测不同的皮质目标。 顺序或同时，提供灵活的工具来调节同时成像的大脑活动 凭借 MRI 的优势，线圈元件将极大地促进扩散。 皮质中的 MRI 编码超出了当前 MRI 梯度技术所能实现的范围，从而能够改进 绘制神经和树突大小及其分布的敏感性，遵循有针对性的神经调节和 为刺激后皮质中的 BOLD-fMRI 提供亚毫米空间分辨率。 在目标 1 中，我们将测试所提出的头阵列 ARES2（用于接收、编码、 匀场和刺激）利用我们在 MR 兼容经颅磁方面的最新进展 刺激 (TMS) 线圈将由大电流驱动，产生最大 1000 mT/m 的梯度和高电流。 转换速率包括 48 个编码线圈，允许 B0 匀场功能，同时 28 个射频线圈。 与编码线圈交错的昆西线圈提供并行成像。 电子设备将允许“刺激”和“成像”模式之间的交替。全面的电子控制。 系统将允许在所有通道上与扫描仪的脉冲序列同步播放任意波形。 在 Aim2 中，我们将系统扩展到完整的 48 通道阵列，我们构建了一个新的 TMS 兼容的 28 通道 RF 接收器。 与 TMS 探针支架设备机械集成的阵列将允许径向。 调整 TMS 探头，使其紧贴头部表面放置。 在 Aim3 中，我们将应用该系统在体内进行亚毫米级的下一代因果脑图绘制 我们将展示 ARES2 提供细胞体（体细胞）和区域特定测量的能力。 这些扩散 MRI 实验将测量运动皮层 (M1) 和体感皮层 (S1) 的神经突大小和密度。 利用 gSlider 体积扩散编码来提高 SNR 并达到 TMS 的亚毫米分辨率。 fMRI，我们将使用9ch TMS和48ch MRI梯度系统以交错的方式进行连续刺激 以及 M1 和 S1 中的功能磁共振成像记录。