NMR Even Echo Rephasing in Slow Laminar Flow
NMR Even Echo Rephasing in Slow Laminar Flow
复制标题
慢层流中的 NMR 均匀回波重定相
DOI：
10.1097/00004728-198408000-00003
复制
发表时间：
1984
影响因子：
1.3
通讯作者：
W. Bradley
中科院分区：
文献类型：
--
作者：
V. Waluch;W. Bradley
在核磁共振成像中，流动的流体具有固定材料所没有的一些不寻常的性质。其中之一是由刚刚进入成像体积的不饱和质子在缓慢流动过程中发出的强烈信号。另一种是观察到，即使是多个自旋-回声列车的回声也比奇数的回声强度更高。这两种现象以前在核磁共振成像文献中没有被区分，术语“矛盾增强”被应用于这两种现象。在这篇交流中，我们考虑了这种现象发生的条件，推导出一般的数学关系，并展示了理解自旋回波再相化特别有用的临床例子。
In nuclear magnetic resonance (NMR) imaging, flowing fluids possess several unusual properties not found in stationary materials. One of these is the strong signal emitted during slow flow by unsaturated protons just entering the imaging volume. Another is the observation that even echoes of a multiple spin-echo train have higher intensity than the odd. The two phenomena have not previously been distinguished in the NMR imaging literature and the term “paradoxical enhancement” has been applied to both. In this communication we consider the conditions under which such a phenomenon occurs, derive general mathematical relationships, and show clinical examples in which an understanding of spin-echo rephasing is especially useful.