An Optimization Algorithm of Active Shimming Current for Magnetic Resonance Imaging System
The impurities of various harmonic orders in region of MRI magnetic field will depress the qualities of the image. Based on the direct proportional relationship of FID signal of MRI system and magnetic field homogeneity, an efficient optimization algorithm of active shimming is presented to correct the inhomogeneous field. FID intensity is used as feedback information to calculate the shim currents with adaptive theory. It makes the calculation process independent of the coils hardware parameters and the correction function of the coils be put forth furthest. The experiment results show that the optimal shim currents can be quickly worked out in less than 3 minutes. Magnetic field homogeneity and qualities of the image are evidently improved by the novel method.
Active shimming shim coils shim currents homogeneity FID
Haicheng WU Li JING Shiyou YANG
College of electrical engineering, Zhejiang University, Hangzhou, China Anhui electric power researc Ningbo Xingaoyi Magnetic Material Company, Yuyao, China College of electrical engineering, Zhejiang University, Hangzhou, China
国内会议
三亚
英文
727-731
2012-08-11（万方平台首次上网日期，不代表论文的发表时间）