高场磁共振并行发射与接收射频系统的关键问题研究

项目名称： 高场磁共振并行发射与接收射频系统的关键问题研究

项目编号： No.51307171

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 电工技术

项目作者： 李烨

作者单位： 中国科学院深圳先进技术研究院

项目金额： 25万元

中文摘要： 高场磁共振系统目前面临的核心问题是激发磁场不均匀产生图像伪影以及人体特异吸收率升高带来的安全问题。并行发射与接收射频系统具有射频匀场能力和高效率的多通道线圈，是解决上述问题的关键。本课题针对高场磁共振并行发射与接收射频系统的多通道线圈设计和发射能量预测与监控的问题，在前期研究基础上，开展多通道线圈性能评估、结构优化和基于能量预测的射频匀场，以及多通道一体化线圈的解耦技术和发射能量实时监测系统的研究，提出综合考虑线圈效率和并行成像能力的多通道线圈性能评估与射频匀场时的能量控制问题的解决方法，阐明多通道一体化线圈的信号耦合与能量耦合机制，验证基于线圈效率上限的结构优化方法和基于能量耦合的射频发射能量预测模型，实现8通道发射，32-64通道接收的射频系统。本项目的成功实施，将促进高场磁共振技术的发展，为自主高端磁共振成像技术与装备的创新和跨越式发展提供理论依据与技术基础。

中文关键词： 磁共振成像；多通道射频线圈；信噪比；特定吸收率；并行技术

英文摘要： The image artifacts and safety issue caused by transmit profile inhomogeneity and specific absorption rate (SAR) raising in subjects are two of the main problems of high field magnetic resonance imaging (MRI). Parallel transmit and receive radio frequency (RF) system is capable to provide the feasibility of utilizing RF shimming and high efficiency multi-channel coil, which are the key solutions for these problems. In this study,we focus on multi-channel coil design and real time transmit power monitoring of parallel transmit and receive system in high field MRI. Based on our preliminary studies, multi-channel coil performance evaluation, structure optimization, coil decoupling techniques, RF shimming strategy with transmit power estimation and RF power monitoring system will be investigated. Additionally, we will present multi-channel coil performance evaluation method, consisting of both coil efficiency and parallel imaging capability, and SAR control method during RF shimming. The signal coupling and power coupling mechanism of multi-channel unitary structure coil will be demonstrated as well. Structure optimization method based on ultimate coil efficiency and transmit power estimation model based on power coupling matrix will be verified. An 8 channel transmit and 32-64 channel receive RF system will be fab

英文关键词： Magnetic Resonance Imaging；Multi-channel radio frequency coil；signal-to-noise ratio；specific absorption rate；parallel transmit