基于多通道并行采集的部分可分离函数高分辨动态磁共振成像

High Spatiotemporal Resolution Magnetic Resonance Imaging Based on Parallel Sampling and Partial Separability Model

部分可分离函数(Partial Separability,PS)是一种高分辨动态磁共振稀疏成像模型,可以对心脏等运动目标实现高分辨动态成像,然而该模型需要充足的扫描数据才能进行图像重建,因此存在扫描时间较长的缺点。文章在PS模型基础上,利用并行成像原理对磁共振数据进行降采样,从而缩短PS模型的扫描时间。数学仿真和载体实验结果表明,该方法可以准确重建出高时空分辨率磁共振图像并且将扫描速度提高2~3倍。

Partially separability(PS) model is a sparse sampling imaging model which can achieve high spatiotemporal resolution for dynamic magnetic resonance imaging. However, the PS model needs a long scan time to collect enough data for image reconstruction, which hinders its applications in clinic. To address this issue, a novel approach based on parallel sampling and image reconstruction algorithm was introduced to shorten the PS scan time in this paper. Numerical simulation and in vivo cardiac experiment results demonstrate that the proposed method can accelerate the PS sampling speed by 2-3 times without any penalty of the reconstructed image quality.