小动物高分辨扩散加权成像在临床MRI上的实现

波谱学杂志 ›› 2012, Vol. 29 ›› Issue (3): 372-378.

小动物高分辨扩散加权成像在临床MRI上的实现

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

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

收稿日期:2011-11-23 修回日期:2011-12-31 出版日期:2012-09-05 发布日期:2012-09-05
通讯作者: 李建奇,jqli@phy.ecnu.edu.cn E-mail:jqli@phy.ecnu.edu.cn
基金资助:
上海市科委基础研究重点资助项目(10JC1414600).

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

WANG Qian-Feng¹, LI Jian-Qi^1*, WU Dong-Mei¹, WANG Xiao-Lou², JIA Jie², ZHANG Min¹, LI Geng-Ying¹ 

1. Shanghai Key Laboratory of Magnetic Resonance Imaging, Department of Physics, East China Normal University, Shanghai 200062, China;
2. Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai 200040, China

Received:2011-11-23 Revised:2011-12-31 Online:2012-09-05 Published:2012-09-05
Contact: LI Jian-Qi,jqli@phy.ecnu.edu.cn E-mail:jqli@phy.ecnu.edu.cn
Supported by:
上海市科委基础研究重点资助项目(10JC1414600).

摘要/Abstract

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3 T 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.

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

Abstract:

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 weighted 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 clinical MRI scanners.

Key words: MRI, diffusion-weighted imaging, navigator echo, high resolution, small animal

中图分类号:

O482.53

王前锋, 李建奇, 吴东梅, 王小楼, 贾杰, 张敏, 李鲠颖. 小动物高分辨扩散加权成像在临床MRI上的实现[J]. 波谱学杂志, 2012, 29(3): 372-378.

WANG Qian-Feng, LI Jian-Qi, WU Dong-Mei, WANG Xiao-Lou, JIA Jie, ZHANG Min, LI Geng-Ying . High-Resolution Diffusion-Weighted Imaging on Small Animals on a Clinical 3 T MRI Scanner[J]. Chinese Journal of Magnetic Resonance, 2012, 29(3): 372-378.

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