Accurate multislice gradient echo T1 measurement in the presence of non-ideal RF pulse shape and RF field nonuniformity
Accurate multislice gradient echo T1 measurement in the presence of non-ideal RF pulse shape and RF field nonuniformity
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DOI：
10.1002/mrm.1112
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发表时间：
2001-05-01
影响因子：
3.3
通讯作者：
Tofts, PS
中科院分区：
文献类型：
--
作者：
Parker, GJM;Barker, GJ;Tofts, PS
提出了一种使用两点技术和标准多层梯度回波序列来估计 T 的方法。该方法明确地校正射频脉冲的形状和发射的射频场强度的空间变化。在 T 的计算中包含这些因素，可以显着提高两点梯度回波 T 的准确度和精度，以及在存在 RF 不均匀性和非理想脉冲轮廓的情况下的测量。该技术的平均准确度为 1.4%，平均精度为 3.0%，沿头部线圈轴的平均变化为 2.3%，(C) 2001 Wiley-Liss, Inc.。
A methodology is presented for estimating T, using a two-point technique with a standard multislice gradient echo sequence. The method explicitly corrects for the shape of the RF pulse and for spatial variations in transmitted RF field intensity. Including these factors in the calculation of T, gives a substantial improvement in accuracy and precision of two-point gradient echo T, measurements in the presence of RF nonuniformity and non-ideal pulse profiles. The mean accuracy of the technique was found to be 1.4%, The mean precision was found to be 3.0%, The mean variation along the axis of a head coil was found to be 2.3%, (C) 2001 Wiley-Liss, Inc.