BLADE刀锋技术详解

Technical detail of BLADE

磁共振成像中,病人运动会产生相位编码方向明显的伪影。伪影主要因为两次激发之间,组织由于运动导致所处空间位置不同所致。关于运动伪影减轻或者消除方法,目前流行的有一维、二维导航回波等。本文主要介绍一种结合快速自旋回波(TSE)和辐射采集的自导航序列:刀锋序列,又称为螺旋桨序列(PROPELLER)。文章重点介绍其数据采集方式,运动纠正方法以及图像重建方法,最后讨论其扫描时间和优缺点。

The motion of patients induces obvious artifacts or ghosts in phase encoding direction during MR scanning. Artifacts or ghosts are generally considered as the result of different position of tissue between shots due to motion. Techniques like 1D or 2D navigator are widely used to eliminate or alleviate artifacts or ghosts in clinical scanning, while another sequence BLADE or PROPELLER with self navigator is introduced in this work which combines Turbo Spin Echo and radial sampling. This work will firstly introduce the sampling trajectory, motion correction and image reconstruction, and end up with the discussion of scanning time, advantage and disadvantage of BLADE.