Li Zhiqiang, Graff Christian, Gmitro Arthur F, Squire Scott W, Bilgin Ali, Outwater Eric K, Altbach Maria I
Department of Radiology, University of Arizona, Tucson, Arizona 85724, USA.
Magn Reson Med. 2009 Jun;61(6):1415-24. doi: 10.1002/mrm.21918.
Three-point Dixon methods have been investigated as a means to generate water and fat images without the effects of field inhomogeneities. Recently, an iterative algorithm (IDEAL, iterative decomposition of water and fat with echo asymmetry and least squares estimation) was combined with a gradient and spin-echo acquisition strategy (IDEAL-GRASE) to provide a time-efficient method for lipid-water imaging with correction for the effects of field inhomogeneities. The method presented in this work combines IDEAL-GRASE with radial data acquisition. Radial data sampling offers robustness to motion over Cartesian trajectories as well as the possibility of generating high-resolution T(2) maps in addition to the water and fat images. The radial IDEAL-GRASE technique is demonstrated in phantoms and in vivo for various applications including abdominal, pelvic, and cardiac imaging.
三点 Dixon 方法已被研究作为一种在没有场不均匀性影响的情况下生成水和脂肪图像的手段。最近,一种迭代算法(IDEAL,具有回波不对称性和最小二乘估计的水和脂肪迭代分解)与梯度和自旋回波采集策略(IDEAL-GRASE)相结合,以提供一种时间高效的脂质-水成像方法,并校正场不均匀性的影响。本文提出的方法将 IDEAL-GRASE 与径向数据采集相结合。径向数据采样对笛卡尔轨迹上的运动具有鲁棒性,并且除了水和脂肪图像之外还具有生成高分辨率 T(2) 图的可能性。径向 IDEAL-GRASE 技术在体模和体内进行了演示,用于包括腹部、盆腔和心脏成像在内的各种应用。