排除磁共振成像中交流干扰的方法探讨  

Study with a method of excluding AC disturbances in MRI

作　　者：王洪[1] 

机构地区：[1]泰山医学院放射学系,泰安271000

出　　处：《中华放射学杂志》2001年第11期865-866,共2页Chinese Journal of Radiology

摘　　要：目的　排除周围环境给磁共振成像造成的交流干扰伪影。方法　通过安装永磁型低磁场强度MR仪 10台 ,对出现的交流干扰图像进行了分析 ,并分别对伪影最严重的 1台和无伪影的 2台进行了环境测量对比 ,通过移开供电线、加隔离变压器、清除金属管道等 ,总结出具体排除干扰方法。结果　交流干扰造成的磁场强度为 2～ 4mGs ,超出允许值 1mGs,形成连套环状伪影。经处理 ,使交流干扰场强降为 1mGs以下 ,图像干扰消逝。结论　安装MRI设备时 ,必须将干扰源移至 10m以外。Objective To exclude AC disturbances resulted from ambient condition in the process of magnetic resonance imaging. Methods study ten low field MRI systems and analysis the images with AC disturbance, then compare measured data of ambience, one of which is disturbed seriously, the other is no disturbance. By removing the power lines and adding isolating transformers and eliminating metal pipes and so on, the useful method is summarized. Results Magnetic field strength giving rise to AC disturbances ranges from 2 mGs to 4 mGs (the standard is less 1 mGs). It will produce circle artifacts. The artifacts pass away when magnetic field strength was decreased to 1 mGs. Conclusion installing MRI sets, disturbing resources must be 10 m far away from them.

关 键 词：磁共振成像 放射学工艺学 质量控制 交流干扰 

分 类 号：R445.2[医药卫生—影像医学与核医学]