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是可视化人脑组织中铁沉积的首选方法 易感加权成像（SWI），用回声 - 平面成像（EPI）绘制功能活性并评估 具有稳态自由进动（SSFP）MRI的颅神经疾病。但是，它对 B0磁场不均匀构成严重挑战。特别强大的局部B0偏差是 在前额叶皮层（PFC）中观察到的鼻窦腔高于鼻腔腔，这是一个涉及许多高阶的大脑区域 认知功能以及轨道包括眼睛和颅神经。空间图像 不均匀的B0条件引起的变形和信号脱落可以严重限制梯度回波MRI 质量甚至使结果毫无用处，从而从根本上限制了其诊断潜力。我们有 最近，在整个大脑中获得高水平的B0同质性的能力取得了重大进步， 包括难以使用新型的多线油硬件与快速B0结合使用的难以舒适的区域，例如PFC 优化方法和动态杂似乎。 B0使用这种动态的多线圈技术 （炸药）与标准方法相比，B0的均匀性非常好，将来应该 接近完全消除B0不均匀性的问题。我们在此提案中的目标是结合 Dynamite B0使用临床RF技术建立了第一个集成的多型线圈B0和Radio- 用于临床诊断和工作流程的频率（MC/RF）设置。特定目标1：电磁场 （EMF）模拟将用于比较和优化生成炸药B0垫片场的潜力 通过驱动RF分阶段的元素，使用专用的多圈B0设置与所使用的RF线圈分开 带有直流电流的阵列或混合方法中的组合，考虑电磁耦合 和安全。特定目的2：计算机辅助设计（CAD）方法，包括电磁，热和热力 机械建模将用于实现临床3T 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性MRI能力。而且， 根据常规临床MRI方案量身定制的炸药B0光滑旋转有望改善整体图像 与传统的基于球形谐波的B0垫技术相比，整个人脑的质量。 特定目标3：炸药B0光滑将应用于视神经疾病的诊断成像 与医务人员完全自动化的时尚透明时尚中的常规协议和工作流程的测试 由于MRI伪像缓解了增强的诊断潜力和真正的临床益处的假设。这 方法是创新的，因为最好的B0杂似乎和RF技术合并了 空前的临床MRI功能。这项研究很重要，因为它有望从根本上 利用腹侧PFC和轨道中梯度回声MRI的诊断潜力，为 最先进的B0垫片技术以及从长凳到床边的真实翻译的广泛临床使用。