Combination of optimized transmit arrays and some receive array reconstruction methods can yield homogeneous images at very high frequencies
Combination of optimized transmit arrays and some receive array reconstruction methods can yield homogeneous images at very high frequencies
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DOI：
10.1002/mrm.20729
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发表时间：
2005-12-01
影响因子：
3.3
通讯作者：
Smith, MB
中科院分区：
文献类型：
--
作者：
Collins, CM;Liu, W;Smith, MB
与高频辐射相关的图像不均匀性是高场成像的主要挑战之一。这种不均匀性可以被认为有两个与射频场相关的因素：发射场分布和接收场分布。调整发射阵列单元中电流的大小和相位可以显著改善高场下的翻转角的均匀性。一些众所周知的并行成像和其他接收阵列后处理方法的有效应用从最终图像中的强度分布中去除了感受性图案，尽管噪声随后成为最终图像中位置的函数。仿真结果表明，在高信噪比的情况下，利用发射阵列和某些接收阵列重建方法相结合，可以在600 MHz的频率下获得非常均匀的人头图像。Magn Reson Med 54：1327-1332,2005.(C)2005年Wiley-Liss，Inc.
Image inhomogeneity related to high radiofrequencies is one of the major challenges for high field imaging. This inhomogeneity can be thought of as having 2 radiofrequency-field related contributors: the transmit field distribution and the reception field distribution. Adjusting magnitude and phase of currents in elements of a transmit array can significantly improve flip angle homogeneity at high field. Effective application of some well-known parallel imaging and other receive array post-processing methods removes receptivity patterns from the intensity distribution in the final image, though noise then becomes a function of position in the final image. Here simulations are used to show that, assuming high signal-to-noise ratio, very homogeneous images in the human head can be acquired with the combination of transmit arrays and some receive array reconstruction methods at frequencies as high as 600 MHz. Magn Reson Med 54:1327-1332,2005. (c) 2005 Wiley-Liss, Inc.