Magland Jeremy, Epstein Charles L
LSNI, Department of Radiology, HUP, University of Pennsylvania, USA.
J Magn Reson. 2004 Dec;171(2):305-13. doi: 10.1016/j.jmr.2004.09.004.
In a paper of Nielson et al. it is shown, using the linear approximation, that it might be possible to create a pair of RF-pulses, which, after summation of the unrephased signals achieve a specified transverse magnetization. Such pulses, designed using the linear approximation, show rather poor slice selectivity. Using the inverse scattering transform formalism we give an algorithm to exactly achieve a specified "summed" transverse magnetization profile. Indeed for a constant phase transverse profile, our algorithm produces infinitely many solutions.
在尼尔森等人的一篇论文中表明，利用线性近似，有可能创建一对射频脉冲，在对未重聚信号求和后可实现特定的横向磁化强度。使用线性近似设计的此类脉冲，其切片选择性相当差。利用逆散射变换形式，我们给出一种算法，以精确实现特定的“求和”横向磁化强度分布。实际上，对于恒定相位的横向分布，我们的算法会产生无穷多个解。
