Optimized ultra-fast imaging sequence (OUFIS).
Optimized ultra-fast imaging sequence (OUFIS).
复制标题
优化的超快成像序列 (OUFIS)。
DOI：
10.1002/mrm.1910330311
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发表时间：
1995
影响因子：
3.3
通讯作者：
Lowe,IJ
中科院分区：
文献类型：
--
作者：
Zha,L;Lowe,IJ
DUFIS序列可以在不使用快速切换梯度的情况下制作超快图像（<10 ms）。RF激励序列是空间选择性的，使得仅使用每个成像像素中的磁化的一小部分，这产生差的成像信噪比（SNR）。我们已经开发了几种替代RF序列，这些序列使用具有多个相位的RF脉冲，并且仅具有0°和180°相位，以激发像素中的几乎所有磁化，并大大提高SNR。这些脉冲序列（现在称为OUFIS）的优化已经进行了分析和数值搜索，与各种线性和非线性模型。文中详细介绍了优化过程中所采用的理论和计算方法。初步的实验结果简要介绍了几种可能的应用OUFIS激发序列的建议。
The DUFIS sequence can make ultra‐fast images (˜10 ms) without the use of rapidly switched gradients. The RF excitation sequence is spatially selective so that only a small fraction of the magnetization in each imaging pixel is used which produces a poor imaging signal to noise ratio (SNR). We have developed several alternative RF sequences that use RF pulses with multiple phases, and also with just 0° and 180° phases to excite almost all the magnetization in a pixel and greatly improve the SNR. The optimization of these pulse sequences (now called OUFIS) have been conducted both analytically and by numerical searches, with various linear and nonlinear models. Both theoretical and computational methods used in the optimizations are described in detail. Preliminary experimental results are briefly presented with several possible applications of the OUFIS excitation sequences suggested.