4 Tesla MR Spectroscopy Console Upgrade

描述（由申请人提供）：本提案旨在资助对McLean医院4台特斯拉瓦里安全身多核磁共振成像系统进行全面翻新。该仪器自2001年5月首次安装以来，既作为新光谱技术的开发平台，又作为将这些技术应用于NIH资助项目的数千个主题的手段，一直具有极高的生产力。然而，磁共振领域的快速技术发展意味着该领域的最新进展很难或不可能在当前的硬件上实现。这一点尤其重要，因为我们正在麦克林建立一个转化项目，将4T与新的9.4T瓦里安动物扫描仪（目前正在安装）合作，我们希望在那里开发可能对人类有用的技术。我们目前的4T扫描仪，特别是控制台硬件和用户界面，曾经处于技术的前沿，已经过时了。这表现在越来越多的不可靠性和停机时间，继续需要广泛的用户培训，以及工作人员物理学家为维修和维护系统而进行耗时的干预。拟议的升级将取代光谱仪的心脏；由信号产生、测量、处理和接口组成。磁铁，梯度，垫片供应和功率放大器，保持良好的工作秩序，并将保留。这提供了一个独特的机会，通过利用现有磁铁和坐式基础设施的价值，以新设备成本的一小部分获得最先进的磁共振光谱仪。自2001年以来，瓦里安MR控制台硬件的各个方面都取得了重大技术进步；数字射频接收机硬件对稀有化合物具有更高的检测灵敏度，在长时间采集中具有更好的时间稳定性，并且以最小的相位滚动进行更清晰的滤波，从而显着提高了光谱定量。新的射频前端改善了噪声系数，实现了更灵活的发射接收配置。并行射频传输和接收改善射频均匀性，可以减少功率沉积，并可以通过使用相控阵和传感技术提高信噪比和速度图像和核磁共振成像采集。修改后的接地拓扑进一步提高了信噪比。最后，新的、更快的工作站提高了采集和处理效率。相关性：麦克林4T扫描仪是美国在人类中进行多核磁共振光谱的领先站点之一；我们经常使用1H， 31P, 7Li, 23Na， 19F和13C光谱来研究广泛的精神和药物滥用障碍。多核磁共振光谱是评估这些疾病的新疗法的极其重要的工具；这一升级将使该扫描仪保持在该领域的前沿，并将为快速将其他动物的发现转化为人类提供新的机会。

DESCRIPTION (provided by applicant): This proposal is to fund a complete refurbishment of the McLean Hospital 4 Tesla Varian Whole Body Multinuclear Magnetic Resonance Imaging system. This instrument has been extremely productive since it was first installed in May, 2001 both as a development platform for new spectroscopy techniques, and as the means for applying these techniques in several thousand subjects for NIH funded projects. However, the rapid pace of technical development in the MR field means that recent advances in the field are difficult or impossible to implement on the current hardware. This is especially relevant as we are building a translational program at McLean that will partner the 4T with a new, 9.4T Varian animal scanner (currently being installed), where we expect to develop techniques that may be useful in humans. Our current 4T scanner, particularly the console hardware and user interface, once at the forefront of technology, has become dated. This has manifested itself in increasing unreliability and downtime, continued requirements for both extensive user training, and time-consuming interventions from staff physicists to repair and maintain the system. The proposed upgrade will replace the heart of the spectrometer; the signal generation, measurement, processing and interface components. The magnet, gradients, shim supply and power amplifiers, remain in excellent working order and will be retained. This offers a unique opportunity to acquire a state of the art MR spectrometer at a fraction of the cost of a new unit, by leveraging the value of the existing magnet and sitting infrastructure. Since 2001, there have been significant technical advances in all aspects of Varian's MR console hardware; digital radiofrequency receiver hardware gives much higher detection sensitivity of rare compounds, better time stability in long acquisitions, and sharper filtering with minimal phase roll, which significantly improves spectral quantitation. A new RF front end improves noise figure and enables more flexible transmit receive configurations. Parallel RF transmission and reception improves RF homogeneity, can reduce power deposition, and can increase SNR and speed image and MRSI acquisition through the use of phased array and SENSE techniques. Revised grounding topology further improves SNR. Finally, the new, faster workstation improves acquisition and processing efficiency. Relevance: The McLean 4T scanner is one of the leading sites in the US for performing multinuclear MR spectroscopy in humans; we routinely employ 1H, 31P, 7Li, 23Na, 19F and 13C spectroscopy to study a wide range of psychiatric and substance abuse disorders. Multinuclear MR spectroscopy is an extremely important tool for evaluating new therapies for these disorders; this upgrade will keep this scanner at the forefront of the field, and will open up new opportunities for rapidly translating discoveries made in other animals to humans. PUBLIC HEALTH RELEVANCE This proposal is to fund a complete refurbishment of the McLean Hospital 4 Tesla Varian Whole Body Multinuclear Magnetic Resonance Imaging system. This scanner is one of the leading sites in the United States for performing multinuclear MR spectroscopy in humans; we routinely employ 1H, 31P, 7Li, 23Na, 19F and 13C spectroscopy to study a wide range of psychiatric and substance abuse disorders. Multinuclear MR spectroscopy is an extremely important tool for evaluating new therapies for these disorders; this upgrade will keep this scanner at the forefront of the field, and will open up new opportunities for rapidly translating discoveries made in other animals to humans.