Hamilton C A
Department of Radiology, Bowman Gray School of Medicine, Winston-Salem, NC 27157-1022.
Magn Reson Imaging. 1994;12(7):1127-30. doi: 10.1016/0730-725x(94)91245-r.
The phase difference method of phase contrast MR angiography provides a means of measuring the average velocity in each voxel of an MR scan. When static tissue is present in a voxel containing flow, the measured velocity is not the average velocity of the flow alone, but is lower due to the partial volume effect of the static tissue. We present a preprocessing technique that removes the contribution of static tissue in each voxel prior to calculation of average velocity, resulting in more accurate velocity measurements and better lumen definition. Results of flow tube experiments are presented which confirm the improvement in measurement accuracy.
相位对比磁共振血管造影的相位差方法提供了一种测量磁共振扫描中每个体素平均速度的手段。当包含血流的体素中存在静态组织时，所测量的速度并非仅为血流的平均速度，而是由于静态组织的部分容积效应而降低。我们提出一种预处理技术，该技术在计算平均速度之前去除每个体素中静态组织的贡献，从而实现更准确的速度测量和更好的管腔定义。文中给出了流管实验的结果，证实了测量准确性的提高。
