Stenger V Andrew, Giurgi Marius S, Boada Fernando E, Noll Douglas C
Department of Medicine, University of Hawaii, Honolulu, Hawaii 96813, USA.
Magn Reson Med. 2006 Sep;56(3):692-7. doi: 10.1002/mrm.21000.
An extension of the "UNaliasing by Fourier encoding the Overlaps using the temporaL Dimension" (UNFOLD) method to the excitation domain (XUNFOLD) is presented to improve the temporal resolution of multishot tailored RF (TRF) pulses. Multishot three-dimensional TRF pulses were designed to produce a time series of images with periodically aliased excitation profiles. The XUNFOLD method is shown to remove the excitation profile aliasing from the dynamic imaging data by filtering in the temporal frequency dimension. The technique is demonstrated to improve the temporal resolution of simulated functional MRI (fMRI) activation in a time series of brain images.
本文提出了一种将“利用时间维度对重叠区域进行傅里叶编码去伪影”（UNFOLD）方法扩展到激发域的方法（XUNFOLD），以提高多激发定制射频（TRF）脉冲的时间分辨率。设计多激发三维TRF脉冲以生成具有周期性伪影激发轮廓的时间序列图像。结果表明，XUNFOLD方法通过在时间频率维度上进行滤波，可从动态成像数据中消除激发轮廓伪影。该技术在一系列脑图像中提高了模拟功能磁共振成像（fMRI）激活的时间分辨率。
