【作者】 李会香； 谢德馨； 任自艳；

【Author】 Li Huixiang 1 Xie Dexin1 Ren Ziyan2(1.Liaoning Shenyang Shenyang University of Technology 110870 2.Korea Cheongju Chungbuk National University 361-763)

【机构】 辽宁沈阳沈阳工业大学电气工程学院； 韩国清州忠北国立大学电气工程学院；

【摘要】 磁共振成像(MRI)系统的成像质量与其主磁体的磁场均匀度有密切关系。对于开放式永磁型MRI,无源匀场是当前研究的热点与难点。本文根据匀场极面垫片的分布特点,提出了整体匀场、部分匀场、整体匀场与部分匀场相结合的三种无源匀场方案。为了验证匀场方案的可行性,本文首先利用电磁场分析软件ANSOFT对三种匀场方案分别进行仿真。仿真结果表明,整体匀场与部分匀场相结合的匀场方案优于整体匀场和部分匀场方案。后与MRI磁体生产企业合作,采用最优匀场方案进行了实际的匀场试验。试验结果也证明了匀场方案的有效性。更多还原

【Abstract】 In Magnetic Resonance Imaging(MRI) system,the image quality is closely related to the magnetic field homoginity of the main magnet.For open permanent MRI,passive shimming is a hot and difficult area in current research.In this paper,whole shimming,part shimming,and combination of the whole shimming with part shimming are proposed,based on distributing characteristic of shims on the surface of shimming poles.In order to verify the feasibility of the shimming schemes,simulations of three schemes are implemented separately using electromagnetic field analysis software ANSOFT.The simulation results show that the combination of whole shimming with part shimming is better than the whole shimming and part shimming.And then,shimming test with the best shimming scheme is carried out through cooperation with enterprises producing MRI magnet.The test results also show the validity of this shimming scheme.更多还原