结构化的低级重建为无导航器水/脂肪分离的多射击扩散权重的EPI
Yiming Dong1, Kirsten Koolstra2, Ziyu Li3
1C.J. Gorter MRI Center, Department of Radiology, LUMC, Leiden, The Netherlands.
Magnetic resonance in medicine
|September 27, 2023
概括
这项研究引入了一种新的无导航器算法,用于多次射击扩散加权MRI. 该方法有效地纠正运动诱导的相位变化,并分离水/脂肪信号,改善各种解剖学的图像质量.
科学领域:
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 医学物理 医学物理
- 图像重建 图像的重建
背景情况:
- 多射击回声平面成像 (EPI) 增强了MRI分辨率,但容易受到运动诱导的相位变化.
- 将EPI与化学转移编码 (Dixon) 结合起来,可以分离水/脂肪信号,但会加剧运动工件.
- 现有的方法往往需要导航员或与同时运动校正和水/脂肪分离作斗争.
研究的目的:
- 开发一个无导航器算法,同时进行水/脂肪分离和运动校正,以多次射击扩散权重EPI.
- 为了应对混合EPI-DixonMRI序列中射击到射击相位变化的挑战.
- 为了提高扩散权重MRI的稳定性和适用性.
主要方法:
- 一个代的,基于模型的重建管道,利用结构化的低级规范化.
- 数据驱动的估计和消除射击到射击相位变化.
- 同时分离水和脂肪图像使用化学转移编码.
主要成果:
- 拟议的算法有效地纠正相位变化,并在模拟和体外实验中分离水/脂肪信号.
- 与额外导航和自导航方法相比,证明了卓越的性能.
- 实现了采样不足的数据集的重建,并促进了部分里埃重建.
结论:
- 开发的算法为消除相位变化和分离水/脂肪图像提供了强大的解决方案.
- 它显示了在不同解剖区域推进扩散加权MRI的重大前景.
- 无导航器的方法简化了扫描协议,并提高了临床适用性.
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