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.

项目总结/摘要 该提案的主要目标是开发一种新的方法来设计阵列线圈， 核成像和光谱学。该方法将避免使用谐振电路的阻抗 匹配，并使用专门的低阻抗前置放大器提供“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。在每个线圈上仅设想一个电容性元件，这是相对非线性的。 具体的，但将补偿线圈的电抗。标准技术可以使一个电路 元件，以在多个频率下进行补偿，使得一个阵列线圈元件能够在多个频率下使用。 频率. 广泛地说，这个项目的动机是MRI和MRS的使用迅速增加， 氢原子以外的原子核。在几乎所有非1H收购的情况下，最好还能够 成像氢，并且通常以同时或交错方式。同时进行多核MRI和 MRS从该领域的最早期就被提出，最近由于 超极化MR、高场磁体的发展，以及多通道磁共振成像的日益可用性， 宽带接收器超极化MRI使其他原子核的光谱成像成为可能 提供了大量表征体内代谢事件的新兴机会。然而，短 极化的寿命驱动了对阵列线圈的需要，以提供成像加速。多重 频率阵列线圈使用当前技术是极其复杂的。这里介绍的方法将 降低了阵列线圈设计的成本和复杂性，消除了多核研究的进入障碍， MRI和MRS。 本项目的具体目标是研究和优化射频线圈阵列的接口，以实现低噪声 本文介绍了一种新的多频阵列设计方法。确定了三个目标：第一， 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aim 1中的最佳方法，然后第三次比较使用常规方法构建的线圈阵列 采用目标1和2中的最佳性能方法建立多频阵列的方法。所有 设计程序将被内置到MATLAB脚本中，并与所有细节一起沿着公开提供， 本项目中使用的测试阵列，以帮助其他研究人员设计多频阵列。