MULTICHANNEL TRANSMIT FRONTEND FOR 7 TESLA

说明书(由申请人提供)：本申请所需的具体采集是一种八通道射频(RF)发射前端，能够产生特定于通道的、用户定义的RF脉冲模式，以驱动多通道发射或发射/接收7特斯拉的RF阵列线圈中的独立发射元件。拟议的硬件将被整合到位于明尼苏达大学磁共振研究中心(CMRR)的现有7Tesla仪器中。这7特斯拉是位于CMRR的NIH资助的生物技术研究资源中心(P41 RR08079)和神经科学蓝图中心核心(P30 NS057091)的中心仪器，并以此身份支持明尼苏达大学内外的大量NIH资助的研究人员和项目。因此，拟议的升级将影响大量用户。这一要求是基于这样一个事实，即一般的成像，特别是磁共振成像，已经发展成为当代基础和临床生物医学研究不可或缺的一部分，是许多学科发现的核心。在这一发展中，最近的工作已经确定，超强磁场(7特斯拉)提供了许多优势，并出现在这一方法的前沿。然而，传统的激发磁共振信号的方法在大脑中是次优的，在7特斯拉的人体中根本不起作用，因为质子共振频率的RF波长是~12厘米，因此小于人头或身体的尺寸。在这种情况下，由传统的单通道发射系统产生的射频(RF)场对于大多数生物医学应用来说是高度不均匀和耗电的。这个问题的解决方案取决于在多个自由度上动态控制RF激励场的能力。拟议的仪器能够实现这一点，并且对于优化使用7个特斯拉人体研究平台是不可或缺的。 公共卫生相关性：磁共振成像(MRI)是用于研究人体在健康和疾病方面的生物医学复杂性的技术中最强大的工具之一。这项提议要求为仪器提供资金，这些仪器将通过使用更高的磁场来显著增强磁共振成像，而更高的磁场可以提供显著的收益，前提是与它们相关的挑战能够得到解决。

DESCRIPTION (provided by applicant): The specific acquisition desired in this application is a eight-channel radiofrequency (RF) transmit front-end capable of generating channel-specific, user- defined RF pulse patterns to drive independent transmit elements in a multichannel transmit or transmit/receive RF array-coil at 7Tesla. The proposed hardware will be incorporated into an existing 7Tesla instrument located within the University of Minnesota's Center for Magnetic Resonance Research (CMRR). This 7 Tesla is the central instrument in the NIH-funded Biotechnology Research Resource Center (P41 RR08079) and the Neuroscience Blueprint Center Core (P30 NS057091) located at the CMRR, and, in this capacity, supports a large number of NIH funded investigators and projects both within and outside of the University of Minnesota. As such, the proposed upgrade will impact a large number of users. This request is based on the fact that imaging in general and magnetic resonance (MR) imaging in particular has evolved to become an indispensible part of contemporary basic and clinical biomedical research, central to discoveries in a large number of disciplines. In this development, recent work has established that ultrahigh magnetic fields (7 Tesla) provide numerous advantages and are emerging at the forefront of this methodology. However, conventional means of exciting MR signals are suboptimal in the brain and simply do not work in the human body at 7 Tesla where the RF wavelength at the proton resonance frequency is ~12 cm and, thus, smaller than the dimensions of the human head or body. In this regime, the radiofrequency (RF) field generated by conventional single, channel transmit systems, is highly non-uniform and power consumptive for most biomedical applications. Solutions to this problem depend on the ability to dynamically control the RF excitation field over a number of degrees of freedom. The proposed instrument is capable of achieving this and is indispensible in the optimal use of the 7 Tesla platforms on human studies. PUBLIC HEALTH RELEVANCE: Magnetic resonance imaging (MRI) is one of the most powerful tools in the armamentarium of techniques employed to investigate the biomedical complexities of the human body in health and disease. This proposal requests funds for instrumentation that will provide a significant enhancement in MRI by enabling the use of higher magnetic fields, which provide significant gains provided that challenges associated with them, can be solved.