Butts K, de Crespigny A, Pauly J M, Moseley M
Department of Radiology, Stanford University, CA 94305-5488, USA.
Magn Reson Med. 1996 May;35(5):763-70. doi: 10.1002/mrm.1910350518.
This work describes a diffusion-weighted (DW) interleaved echo-planar imaging (IEPI) method for use on either conventional whole-body scanners or scanners equipped with high-speed gradient and receiver hardware. In combination with cardiac gating and motion correction with a pair of orthogonal navigator echoes, the presented method is time-efficient, compensates for patient motions, and is less sensitive to image distortions than single-shot methods. The motion-correction scheme consists of correction for constant and linear phase terms found from the orthogonal navigator echoes. The correction for the linear phase term in the phase-encode direction includes gridding the data to the Cartesian grid. The DW IEPI was used to image a phantom rotating about the slice-select direction, and motion correction was performed to eliminate ghost artifacts arising from motion in either the readout- or phase-encoding directions. DW IEPI with motion correction was performed on a normal volunteer and on a patient with a 26-day-old region of ischemia over much of the right hemisphere.
这项工作描述了一种扩散加权（DW）交错回波平面成像（IEPI）方法，可用于传统的全身扫描仪或配备高速梯度和接收器硬件的扫描仪。结合心脏门控和利用一对正交导航回波进行运动校正，所提出的方法具有时间效率，可补偿患者运动，并且比单次激发方法对图像畸变的敏感性更低。运动校正方案包括对从正交导航回波中找到的恒定和线性相位项进行校正。在相位编码方向上对线性相位项的校正包括将数据网格化到笛卡尔网格。DW IEPI用于对围绕切片选择方向旋转的体模进行成像，并进行运动校正以消除由读出或相位编码方向上的运动引起的鬼影伪影。对一名正常志愿者和一名右半球大部分区域有26天缺血区域的患者进行了带运动校正的DW IEPI检查。
