磁共振成像系统的一种快速涡流补偿方法  

A Rapid Method of Eddy Current Compensation in Magnetic Resonance Imaging Systems

作　　者：刘正敏[1] 周荷琴[1] 武海澄[1] 

机构地区：[1]中国科学技术大学自动化系,安徽合肥230027

出　　处：《中国医疗器械杂志》2005年第6期410-413,共4页Chinese Journal of Medical Instrumentation

基　　金：宁波市科技创新项目(2003D 10057)

摘　　要：在磁共振成像系统中，梯度磁场用来对成像物体进行空间编码。梯度磁场的快速切换会导致涡流的产生，影响磁场的变化， 造成图像伪影。基于梯度电流预补偿技术，提出了一种利用电磁感应原理以及数据拟合方法快速获得涡流补偿参数的方法。 实验证明该方法显著地缩短了调试时间，对涡流进行了有效的补偿，明显提高了图像质量。Imaging objects are spatially encoded by gradient magnetic fields in magnetic resonance imaging systems. The eddy current caused by rapid switches of gradient fields will result in artifacts in the images. A method of eddy current compensation based on pre-emphasis of gradient current is presented inthis thesis. The compensation parameters are acquired rapidly utilizing Faraday＇s induction theorem and data fitting method. The experiments prove that the method is efficient for reduction of the debugging time and for the improvement of the image quality.

关 键 词：涡流 梯度磁场 磁共振成像 

分 类 号：R445.2[医药卫生—影像医学与核医学]