A Prototype Wireless Digital MR Spectrometer on a Single Integrated Circuit

单个集成电路上的无线数字磁共振波谱仪原型

• 批准号: 8710219
• 负责人: ROLAND BAMMER
• 金额: $ 22.84万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8710219
• 关键词: Affect; Anesthesia procedures; Architecture; Back; Brain; Calibration; Callback; Childhood; Clinic; Clinical; Clinical Protocols; Communication; Consumption; Coupling; Data; Dependence; Development; Devices; Diagnosis; Diagnostic; Dimensions; Elderly; Electronics; Feeds; Forehead; Freedom; Future; Head; Health Care Costs; Healthcare; Healthcare Systems; Heating; Housing; Human Resources; Image; Individual; Lead; Left; Lesion; Link; Magnetic Resonance Imaging; Masks; Measurement; Measures; Mechanics; Morphologic artifacts; Motion; Movement; Neurologic; Optics; Pathology; Patients; Pediatrics; Performance; Phase; Philosophy; Photons; Physiologic pulse; Positioning Attribute; Positron-Emission Tomography; Printing; Process; Public Health; RF coil; Reading; Resistance; Risk; Safety; Sampling; Scanning; Sedation procedure; Signal Transduction; Silicon; Solutions; Source; Staging; Stress; Subject Headings; System; Techniques; Technology; Time; Tissues; Translations; Update; Validation; Wireless Technology; Work; analog; base; cost; design; digital; feeding; flexibility; high risk; image processing; improved; innovation; microchip; miniaturize; motor disorder; new technology; novel strategies; operation; patient population; patient safety; portability; prototype; public health relevance; radiologist; skills; tool development; transmission process; trend; wireless fidelity; wireless network

DESCRIPTION (provided by applicant): The final deliverable of this project is a powerful microchip, or system-on-a-chip (SOC), that contains the functionality of a complete digital MR spectrometer and wireless transmitter. The three specific aims present an iterative, three stage strategy for chipset development. With the completion of each specific aim, the deliverables will be fully functional chipsets with decreasing footprint until we reach the dimensions of the final SOC. We begin with a 50x50x20mm prototype on a printed circuit board that will eventually be reduced to a miniature 2x2x1mm complete SOC blueprint. This microchip technology will be the centerpiece of a wireless, digital RF chain that is superior in performance to the traditional wired, analog RF chain, and is a paradigm shift for the entire field of MRI. Integration of this microchip into an RF coil will enable digital processing of the MR signal to be performed directly on the coil, followed by digital wireless signal transmission, thereby improving SNR and removing all mechanical connections between the RF coil and MR scanner. Specifically, we will develop the microchip technology for integration into a miniature RF coil-based "wireless marker", whose position can be tracked inside the MR scanner bore. Motion tracking of the head is performed using three wireless markers that are easily placed on the forehead, which will provide pose information for real-time motion correction of brain MRI. This application fittingly highlights the strengths of the microchip approach (miniature, wireless device), as well as our significant in-house expertise in motion correction. Head motion is still a fundamental problem for brain MRI, which adds to healthcare costs while also reducing diagnostic confidence. A wireless marker based motion correction solution will significantly benefit healthcare by reducing prep/scan time, costs, and stress to patient that are caused by a dependence on anesthesia and repeat scans due to motion. The diagnostic quality of MRI will also be improved, particularly in patient populations who have difficulty keeping still (e.g. pediatrics, elderly). Wireless markers also possess several advantages over alternative techniques, including: (1) improved patient safety by eliminating electrically conducting wires that can cause tissue heating; (2) no additional load is placed on the existing MR receiver hardware since communication occurs within its own wireless network; (3) compatibility with a wide range of clinical scans, as only a short navigator pulse-sequence is needed for position measurement; (4) does not require any cross-calibration routines (e.g. optical camera tracking), since tracking and imaging are performed in the same MR coordinate system; and (5) importantly, a miniature, wireless-marker tracking-device will be easy to use, thereby facilitating their portability to the high-throughput clinic. Looking beyond motion correction (and the scope of this R21), the powerful chipsets are an enabling technology for wireless, digital communication between ALL RF coils and the MR scanner. The chipset digitizes the MR signal directly on the RF coil, digitally modulates, and wirelessly transmits the digital MR signal. SNR i therefore increased by avoiding resistive losses and coupling due to long coaxial cables. In the case of a multi-channel imaging RF coil, each channel would have a matching set of on-coil microchips that perform all MR spectrometer operations. By performing these operations directly on the RF coil, the MR scanner becomes channel independent, and RF channel upgrades a thing of the past. An array of microchips may be deployed in a massively multi-channel coil, thereby facilitating the trend in MRI towards parallel imaging. Finally, the elimination of cables and large oncoil electronics will result in lighter and easier to handle RF coils. Digital wireless links in MRI may also benefit from similar technology that is being rapidly advanced in the field of modern mobile telephony. In summary, the powerful chipsets developed here will not only influence motion correction, but also innovate a fully digital and fully wireless MR scanner in the future. In the current R21, we expect to produce a high-impact motion correction strategy that is, overall, the most comprehensive, robust, and patient friendly solution to date. The technology and preliminary results garnered will then be used for two future R01 proposals. The first R01 will be for clinical validation of an even more refined wireless marker. The second R01 will be to refine and validate a high-fidelity wireless spectrometer IC for imaging RF coils. Another future application would be MR-PET where a small footprint IC spectrometer would eliminate a lot of the current x-ray dense RF electronics, which interacts with 511keV photons and thus perturbs the PET imaging process.

描述（由申请人提供）：该项目的最终交付成果是一个功能强大的微芯片或片上系统（SOC），包含完整的数字MR光谱仪和无线发射器的功能。这三个具体目标为芯片组开发提出了一个迭代的三阶段战略。随着每个具体目标的完成，交付的产品将是功能齐全的芯片组，占用空间越来越小，直到我们达到最终SOC的尺寸。我们开始在印刷电路板上制作50 x 50 x 20 mm的原型，最终将缩小到微型2 x 2 x 1 mm的完整SOC蓝图。这种微芯片技术将成为无线数字RF链的核心，其性能上级传统的有线模拟RF链，是整个MRI领域的范式转变。将该微芯片集成到RF线圈中将使得能够直接在线圈上执行MR信号的数字处理，然后进行数字无线信号传输，从而提高SNR并消除RF线圈和MR扫描仪之间的所有机械连接。具体来说，我们将开发集成到微型RF线圈为基础的“无线标记”，其位置可以在MR扫描仪孔内跟踪的微芯片技术。头部的运动跟踪是使用三个无线标记来执行的，这些标记可以很容易地放置在前额上，这将为大脑MRI的实时运动校正提供姿势信息。该应用恰当地突出了微芯片方法（微型，无线设备）的优势，以及我们在运动校正方面的重要内部专业知识。头部运动仍然是脑部MRI的一个基本问题，这增加了医疗成本，同时也降低了诊断信心。基于无线标记的运动校正解决方案将通过减少准备/扫描时间、成本和对患者的压力而显著有益于医疗保健，所述压力是由依赖于麻醉和由于运动而重复扫描引起的。MRI的诊断质量也将得到改善，特别是在难以保持静止的患者人群中（例如，儿科、老年人）。无线标记物还具有优于替代技术的若干优点，包括：（1）通过消除可能导致组织加热的导电线来提高患者安全性;（2）由于在其自身的无线网络内进行通信，因此不会对现有MR接收器硬件施加额外负载;（3）与广泛的临床扫描兼容，因为位置测量仅需要短的导航脉冲序列;（4）不需要任何交叉校准例程（例如，光学相机跟踪），因为跟踪和成像在相同的MR坐标系中执行;以及（5）重要的是，微型无线标记跟踪设备将易于使用，从而促进了对图像的跟踪。 他们的便携性高通量诊所。除了运动校正（以及R21的范围）之外，功能强大的芯片组是所有RF线圈和MR扫描仪之间无线数字通信的一种实现技术。芯片组直接在RF线圈上数字化MR信号，数字调制并无线传输数字MR信号。因此，通过避免长同轴电缆引起的电阻损耗和耦合，SNR i得以提高。在多通道成像RF线圈的情况下，每个通道将具有执行所有MR光谱仪操作的匹配的一组线圈上微芯片。通过直接在RF线圈上执行这些操作，MR扫描仪变得独立于通道，并且RF通道升级成为过去。微芯片阵列可以部署在大规模多通道线圈中，从而促进MRI朝向并行成像的趋势。最后，取消电缆和大型线圈上的电子器件将使RF线圈更轻，更容易操作。数字无线 MRI中的链路也可以受益于在现代移动的电话领域中快速发展的类似技术。总之，这里开发的功能强大的芯片组不仅会影响运动校正，而且还会在全数字化和全无线MR扫描仪中进行创新。 未来在当前的R21中，我们希望产生一种高影响力的运动校正策略，即迄今为止最全面、最强大、最适合患者的解决方案。所获得的技术和初步结果将用于两个未来的R 01提案。第一个R 01将用于临床验证更精细的无线标记。第二个R 01将改进和验证用于成像RF线圈的高保真无线光谱仪IC。另一个未来的应用将是MR-PET，其中小尺寸IC光谱仪将消除许多当前的X射线密集RF电子器件，这些电子器件与511 keV光子相互作用，从而干扰PET成像过程。