Automatic RF Signal Tuning and Matching System for MR Imaging and Spectroscopy

 描述（由申请人提供）：磁共振（MR）成像和光谱用于非侵入性地获取人体的结构、功能和生化信息，并进一步利用这种能力进行诊断。磁共振系统的研究趋势已转向超低频磁场（B 0）强度和多通道射频（RF）线圈。然而，在RF线圈及其接口电路中存在未解决的技术问题：由于可变的受试者负载引起的负载效应，以及RF线圈元件的数量增加。加载效应需要困难且耗时的手动频率调谐和阻抗匹配。能够实现并行MR成像的多通道系统需要线圈元件和接口电路的小型化，以防止RF干扰并能够装配到MR扫描仪的孔中。 为了克服这些挑战，题为“Automatic RF signal tuning and matching system for MR imaging and spectroscopy”的本申请提出了一种电驱动自动化系统，以快速准确地调谐和匹配RF线圈。自动系统将在定制设计的MR兼容微芯片上实现。我们最近提出了在7 T氢质子（1H）成像的多通道RF收发器线圈中应用自动系统的可行性。在指导阶段（K99），候选人将获得MRI的非硬件知识，如MR物理学，RF脉冲，MR序列和MR光谱学，以开发专门的RF脉冲和MR序列，利用嵌入在RF线圈中的电路。通过一套硬件和非硬件知识，候选人将在指导期间开发自动频率调谐和阻抗匹配的多核（1H和31 P）RF线圈。随后，将在R 00期间使用定制设计的MR兼容微芯片实现自动系统的小型化。除了自动化功能（频率调谐和阻抗匹配）外，该微芯片还将具有无线控制能力。专门的RF脉冲和序列将有助于微芯片的操作。这种微芯片解决方案将有显著的好处：应用自动功能 在磁孔内或磁孔外以及在MR实验之前或期间，防止由于在磁场处的短波长引起的RF干扰，减小用于支撑大量线圈元件的自动化系统的尺寸，并且消除RF/电互连线和电缆。此外，这项技术有可能将额外的功能和系统集成到MR兼容的定制设计的微芯片中。这个跨学科项目的成功完成将使候选人成为下一代磁共振技术领域的独立研究者。

 DESCRIPTION (provided by applicant): Magnetic resonance (MR) imaging and spectroscopy are used to non-invasively acquire structural, functional, and biochemical information in humans, and further utilizing this capability for diagnostic purpose. The research trends in MR systems have moved towards ultrahigh magnetic field (B0) strengths and multichannel radiofrequency (RF) coils. There, however, are unsolved technical problems in RF coils and its interface circuits: loading effect due to variable subject loads, and an increasing number of RF coil elements. The loading effect requires the difficult and time-consuming manual frequency tuning and impedance matching. Multichannel systems, which enable parallel MR imaging, require miniaturization of coil elements and interface circuits to prevent RF interference and be able to fit into the bore of MR scanners. To overcome these challenges, this application entitled "Automatic RF signal tuning and matching system for MR imaging and spectroscopy" proposes an electrically driven automation system to tune and match RF coils rapidly and accurately. The automatic system will be implemented on a custom designed MR- compatible microchip. We have recently presented the feasibility of applying the automatic system in a multichannel RF transceiver coil for hydrogen proton (1H) imaging at 7T. During mentored phase (K99), the candidate will gain non-hardware knowledge in MRI, such as MR physics, RF pulse, MR sequence, and MR spectroscopy, to develop specialized RF pulses and MR sequences that take advantage of the electrical circuits embedded in an RF coil. With a set of hardware and non-hardware knowledge, the candidate will develop an automatically frequency tuned and impedance matched multi-nucleus (1H and 31P) RF coil during the mentored period. Subsequently, a miniaturization of the automatic system with a custom- designed MR-compatible microchip will be accomplished during the R00 period. This microchip will have wireless control capability in addition to the automated functions (frequency tune and impedance match). The specialized RF pulse and sequence will assist the operation of the microchip. This microchip solution will have significant benefits: applying the automatic functions in or out of magnet bore and before or during MR experiments, preventing RF interferences due to short wavelength at ultrahigh field, reducing the size of the automated system for supporting a large number of coil elements, and eliminating RF/electrical interconnection wires and cables. Furthermore, this technology has the potential to integrate additional functions and systems into a MR-compatible custom-designed microchip. The successful completion of this interdisciplinary project will enable the candidate to become an independent investigator in the area of next- generation MR technology.