Department of Experimental Physics 5, University of Wuerzburg, Germany.
J Magn Reson. 2012 Jan;214(1):61-7. doi: 10.1016/j.jmr.2011.10.005. Epub 2011 Oct 13.
Many MRI sequences use non-selective hard pulse excitation in the presence of imaging gradients. In this work, we investigate to which extent the sinc-shaped frequency excitation profiles of the pulse can be used for imaging without the generation of artefacts. A correction algorithm is proposed that eliminates the influence of the excitation profile. Phantom as well as in vivo measurements prove that enhanced image quality can be obtained as long as the first minimum of the excitation profile lies outside the imaged object.
许多 MRI 序列在存在成像梯度的情况下使用非选择性硬脉冲激发。在这项工作中，我们研究了脉冲的 sinc 形频率激发轮廓在不产生伪影的情况下用于成像的程度。提出了一种校正算法，该算法消除了激励轮廓的影响。 体模和体内测量证明，只要激励轮廓的第一最小值位于成像物体之外，就可以获得更高的图像质量。
