Low-complexity decoupling of multi-frequency arrays for magnetic resonance imaging and spectroscopy using operational amplifiers

使用运算放大器对磁共振成像和光谱学的多频阵列进行低复杂度解耦

• 批准号: 9809911
• 负责人: Steven M Wright
• 金额: $ 21.17万
• 依托单位: TEXAS ENGINEERING EXPERIMENT STATION
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9809911
• 关键词: Acceleration; Amplifiers; Automobile Driving; Cell Nucleus; Clinical; Complex; Custom; Data; Development; Disease; Dose; Echo-Planar Imaging; Elements; Emerging Technologies; Event; Frequencies; Goals; Hydrogen; Image; Imaging Techniques; Liquid substance; Magnetic Resonance; Magnetic Resonance Imaging; Metabolic; Methodology; Methods; Monitor; Motivation; Movement; Noise; Nuclear; Output; Paper; Performance; Procedures; Process; Protons; Publishing; RF coil; Research; Research Personnel; Seminal; Series; Signal Transduction; Spectrum Analysis; Speed; System; Techniques; Technology; Testing; Time; Vision; Work; cost; design; electric impedance; flexibility; in vivo; in vivo imaging; instrumentation; magnetic field; metabolic abnormality assessment; metabolic imaging; novel strategies; procedure cost; sensor; spectroscopic imaging; temporal measurement; tool; virtual; web site

PROJECT SUMMARY/ABSTRACT The broad objective of this proposal is to develop a new approach to the design of array coils for multi- nuclear imaging and spectroscopy. The approach will avoid the use of resonant circuits for impedance matching and for providing ‘preamplifier decoupling’ using specialized low-impedance preamplfiiers. Instead, the proposal uses high-impedance, low-noise, operational amplifiers to operate series tuned coils at multiple frequencies. Only one capacitive element is envisioned on each coil, which is relatively non- specific, but will compensate for the reactance of the coil. Standard techniques can enable that one circuit element to compensate at multiple frequencies, enabling one array coil element to be used at multiple frequencies. The motivation for this project, broadly speaking, is the rapidly increasing utilization of MRI and MRS of nuclei other than hydrogen. In virtually every case of non-1H acquisitions, it is desirable to also be able to image hydrogen, and often in simultaneous or interleaved fashion. Simultaneous multi-nuclear MRI and MRS has been suggested since the earliest days of the field, and is recently reemerging due to the development of hyperpolarized MR, high-field magnets, and the increasing availability of multi-channel broadband receivers. Hyperpolarized MRI is enabling spectroscopic imaging of other nuclei, in turn providing a wealth of emerging opportunities to characterize in vivo metabolic events. However, the short lifetime of the polarization is driving the need for array coils to provide imaging acceleration. Multi- frequency array coils are extremely complex using current technology. The approach presented here will lower the cost and complexity of array coil design, removing an entry barrier to research in multi-nuclear MRI and MRS. The specific goal of this project is to investigate and optimize the interface of RF coil arrays to low-noise preamps to implement this new multi-frequency array design method. Three aims are defined; first to evaluate the noise figure of each of several interface approach, second to assess the decoupling provided by the best approaches from aim 1, and then third to compare coil arrays built using conventional approaches to a multi-frequency array built using the best performing approach from aims 1 and 2. All design procedures will be built into MATLAB scripts and made publicly available, along with all specifics of the test arrays used in this project to assist other researchers to design multi-frequency arrays.

项目概要/摘要 该提案的主要目标是开发一种新的阵列线圈设计方法，用于多用途 该方法将避免使用谐振电路进行阻抗。 匹配并使用专门的低阻抗前置放大器提供“前置放大器去耦”。 相反，该提案使用高阻抗、低噪声运算放大器来操作串联调谐线圈 在多个频率下，每个线圈上只设想一个电容元件，这是相对非 特定的，但会补偿线圈的反应 标准技术可以实现该电路。 元件在多个频率下进行补偿，使一个阵列线圈元件能够在多个频率下使用 频率。 从广义上讲，该项目的动机是 MRI 和 MRS 的利用迅速增加 在几乎所有非 1H 收购的情况下，也希望能够 对氢进行成像，并且通常以同时或交错的方式进行多核 MRI 和 MRS 自该领域最早出现以来就已被提出，并且最近由于以下原因重新出现： 超极化 MR、高场磁体的发展以及多通道可用性的不断提高 宽带接收器反过来又可以对其他核进行光谱成像。 为表征体内代谢事件提供了大量新兴机会。 偏振的寿命推动了对阵列线圈提供成像加速的需求。 使用当前技术，频率阵列线圈极其复杂。 降低阵列线圈设计的成本和复杂性，消除多核研究的进入壁垒 MRI 和 MRS。 该项目的具体目标是研究和优化射频线圈阵列与低噪声的接口 首先定义了实现这种新的多频率阵列设计方法的三个目标； 评估几种接口方法中每种方法的噪声系数，其次评估所提供的解耦 通过目标 1 的最佳方法，然后第三个比较使用传统方法构建的线圈阵列 使用目标 1 和 2 中的最佳性能方法构建多频阵列的方法。全部 设计程序将被内置到 MATLAB 脚本中并公开发布，以及所有细节 该项目中使用的测试阵列是为了协助其他研究人员设计多频阵列。