Dynamic Multi-Coil B0 Shimming for Diagnostic MRI of Frontal Brain

用于额叶诊断 MRI 的动态多线圈 B0 匀场

• 批准号: 10592875
• 负责人: Christoph Juchem
• 金额: $ 8.88万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-13 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10592875
• 关键词: Area; Automobile Driving; Brain; Brain imaging; Clinical; Complex; Computer-Aided Design; Coupling; Cranial Nerves; Cranial nerve diseases; Deposition; Development; Diagnostic; Diagnostic Imaging; Dropout; Echo-Planar Imaging; Electromagnetic Fields; Electromagnetics; Elements; Engineering; Environment; Eye; Future; Generations; Human; Hybrids; Image; Image Analysis; Iron; Magnetic Resonance Imaging; Maps; Mechanics; Medical Staff; Methods; Mission; Modeling; Morphologic artifacts; National Institute of Biomedical Imaging and Bioengineering; Ocular orbit; Optic Nerve; Optic Neuritis; Pathology; Patients; Performance; Phase; Predisposition; Prefrontal Cortex; Protocols documentation; Public Health; RF coil; Research; Safety; Shapes; Signal Transduction; Sinus; Slice; System; Techniques; Technology; Testing; Training; Translations; base; bench-to-bedside translation; brain magnetic resonance imaging; brain tissue; clinical diagnostics; clinical imaging; cognitive function; design; diagnostic value; healthy volunteer; imaging capabilities; improved; innovation; magnetic field; neuroimaging; novel; optic nerve disorder; radio frequency; safety assessment; simulation; tool; translational approach

PROJECT SUMMARY Fast gradient-echo MRI is the preferred method to visualize iron deposition in human brain tissue with susceptibility-weighted imaging (SWI), to map functional activity with echo-planar imaging (EPI) and to assess cranial nerve disorders with steady-state free precession (SSFP) MRI. However, its high susceptibility towards B0 magnetic field inhomogeneity poses serious challenges. Particularly strong and localized B0 deviations are observed above the sinus cavities in the prefrontal cortex (PFC), a brain area involved in many higher order cognitive functions, and the orbits comprising, among others, eyes and cranial nerves. Spatial image deformation and signal dropout induced by inhomogeneous B0 conditions can severely limit gradient-echo MRI quality and even render results useless, thereby fundamentally limiting its diagnostic potential. We have recently made major advances in the ability to obtain high levels of B0 homogeneity throughout the brain, including difficult-to-shim areas such as the PFC using a novel multi-coil hardware in combination with rapid B0 optimization methods and dynamic shimming. B0 shimming with this Dynamic Multi-Coil Technique (DYNAMITE) provides dramatically better B0 homogeneity than standard methods and in the future should close to completely eliminate B0 inhomogeneity as a problem. Our objective in this proposal is to combine DYNAMITE B0 shim with clinical RF technology to establish the first integrated multi-coil B0 and radio- frequency (MC/RF) setup dedicated to clinical diagnostics and workflow. Specific Aim 1: Electromagnetic field (EMF) simulations will be used to compare and optimize the potential of generating DYNAMITE B0 shim fields with a dedicated multi-coil B0 setup separate from the employed RF coil, by driving elements of an RF phased array with DC currents or a combination thereof in a hybrid approach, considering electromagnetic coupling and safety. Specific Aim 2: Computer-aided design (CAD) methods comprising electromagnetic, thermal and mechanical modeling will be used to realize the optimized MC/RF constellation for a clinical 3T MR scanner environment, providing diagnostic MRI capability in an efficient, reliable and safe fashion. Moreover, DYNAMITE B0 shimming tailored to routine clinical MRI protocols is expected to improve the overall image quality throughout the human brain compared to conventional spherical harmonic-based B0 shim technology. Specific Aim 3: DYNAMITE B0 shimming will be applied to diagnostic imaging of optic nerve diseases as part of routine protocols and workflow in a fully automated fashion transparent to the medical staff to test the hypothesis of enhanced diagnostic potential and a true clinical benefit due to MRI artifact mitigation. The approach is innovative because the best available B0 shimming and RF technologies are combined to provide unprecedented clinical MRI capabilities. The research is significant because it is expected to fundamentally leverage the diagnostic potential of gradient-echo MRI in the ventral PFC and orbits, setting the stage for widespread clinical use of state-of-the-art B0 shim technology and true translation from bench to bedside.

项目摘要 快速梯度回波MRI是显示人脑组织铁沉积的首选方法， 磁共振加权成像（SWI），用回波平面成像（EPI）绘制功能活动，并评估 颅神经疾病伴稳态自由旋进（SSFP）MRI。然而，它对 B 0磁场的不均匀性带来了严重的挑战。特别强烈且局部化的B 0偏差是 在前额叶皮层（PFC）的窦腔上方观察到，这是一个涉及许多高级秩序的大脑区域。 认知功能，以及包括眼睛和颅神经等的眼眶。空间图像 由不均匀B 0条件引起的变形和信号丢失会严重限制梯度回波MRI 质量，甚至使结果无用，从而从根本上限制了其诊断潜力。我们有 最近在获得整个大脑高水平B 0同质性的能力方面取得了重大进展， 包括难以匀场的区域，例如PFC，使用新型多线圈硬件结合快速B 0 优化方法和动态匀场。采用动态多线圈技术的B 0匀场 （ANOITE）提供了比标准方法更好的B 0均匀性，未来应 几乎完全消除了B 0不均匀性这一问题。我们在这个提案中的目标是将联合收割机 B 0垫片采用临床射频技术，建立了第一个集成多线圈B 0和无线电- 频率（MC/RF）设置，专用于临床诊断和工作流程。具体目标1：电磁场 (EMF)将使用模拟来比较和优化产生高性能B 0匀场的潜力 通过驱动RF相控的元件，使用与所采用的RF线圈分开的专用多线圈B 0设置 考虑到电磁耦合，在混合方法中具有DC电流或其组合的阵列 和安全性具体目标2：计算机辅助设计（CAD）方法，包括电磁、热、 机械建模将用于实现临床3 T MR扫描仪的优化MC/RF星座 环境，以高效、可靠和安全的方式提供诊断MRI能力。此外，委员会认为， 根据常规临床MRI方案定制的EQUITE B 0匀场预计将改善整体图像 与传统的基于球面谐波的B 0匀场技术相比， 具体目标3：DYNAMITE B 0匀场将应用于视神经疾病的诊断成像，作为其一部分 以完全自动化的方式对医务人员透明的常规协议和工作流程， 增强诊断潜力的假设和MRI伪影缓解带来的真正临床受益。的 这种方法是创新的，因为最好的B 0匀场和RF技术相结合， 前所未有的临床MRI功能。这项研究意义重大，因为它有望从根本上 利用梯度回波MRI在腹侧PFC和眼眶中的诊断潜力，为 最先进的B 0 shim技术在临床上的广泛应用，以及从实验室到床边的真正转换。