小动物高分辨扩散加权成像在临床MRI上的实现  

High-Resolution Diffusion-Weighted Imaging on Small Animals on a Clinical 3 T MRI Scanner

作　　者：王前锋[1] 李建奇[1] 吴东梅[1] 王小楼[2] 贾杰[2] 张敏[1] 李鲠颖[1] 

机构地区：[1]上海市磁共振重点实验室,华东师范大学物理系,上海200062 [2]复旦大学附属华山医院,康复科,上海200040

出　　处：《波谱学杂志》2012年第3期372-378,共7页Chinese Journal of Magnetic Resonance

基　　金：上海市科委基础研究重点资助项目(10JC1414600)

摘　　要：在临床用MRI系统上对小动物扩散加权成像一般采用回波平面成像序列,但是回波平面成像易受偏共振效应的影响,得到的图像伪影大、几何变形严重、图像分辨率低,无法探究微小的生物组织结构.该文报道了在临床用3T MRI系统上采用自旋回波序列实现了高分辨扩散加权成像.为减少运动伪影,序列中整合了导航回波矫正技术.对脑缺血模型大鼠脑部的扫描结果显示,自旋回波扩散加权序列获得的图像基本没有发生形变,并且具有较高的分辨率和较好的信噪比.The most commonly used pulse sequence for small animal diffusion-weighted imaging on clinical MRI scanners is the single shot echo planar imaging （EPI） sequence. However, EPI is susceptible to off-resonance artifacts arising from the inhomogeneity of main field, local susceptibility gradients, and chemical shift, leading to image quality degradation. In this study, we implemented a high-resolution spin-echo diffusion weigh- ted imaging （SE-DWI） on a clinical 3 T MRI scanner. To reduce the motion artifacts, navigator echoes were acquired to correct the phase errors. The results from ischemic rat brain demonstrated that SE-DWI was feasible for imaging small animals on 3 T clini cal MRI scanners.

关 键 词：磁共振成像(MRI) 扩散加权成像 导航回波 高分辨 小动物 

分 类 号：O482.53[理学—固体物理]