反演法设计磁共振射频阵列线圈的研究

doi:10.3969/j.issn.0258-8021.2012.06.004

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摘要磁共振射频阵列线圈技术的出现进一步提高了磁共振成像的质量，但现有的阵列线圈无法凸显局部感兴趣区域(ROI)。为了满足术中磁共振发展的需求，研究反演法在磁共振射频阵列发射线圈设计与优化中的应用。首先根据临床需求确定ROI，设计目标函数，应用反演法计算阵列线圈的电流密度，采用正则化技术优化计算中出现的高病态问题，采用流函数技术求解线圈绕组。根据临床不同需求设计了3种ROI位置的阵列发射线圈，ROI内的磁场强度达到 0.957 4 A/m以上，与目标磁场强度的误差在5%以内，10 cm ROI内磁场均匀度达到5×10^-8以内，满足理论设计要求。实验结果表明，基于反演法设计的射频阵列发射线圈在ROI内的磁场分布符合理论要求，证明反演法在射频阵列发射线圈设计中的适用性。

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	张战胜辛学刚^*

关键词 ：磁共振成像, 阵列线圈, 反演法, 正则化技术

Abstract：Advancement of the magnetic resonance radio frequency (RF) phased array coil technology further can improve the MRI quality. However, the commercial RF phased arrays are not organ-oriented, not able to highlight the located ROI. In this paper, an inverse method is presented for designing RF phased array transmit coil in MRI. First, the ROI was set according to the clinical need, and a target field function was created based on the inverse technology. Next, the current density of the phased array coil was calculated accordingly. The highly ill-posed problem was solved using regularization strategy. Last, the contour charts of the RF phased array coil were obtained by using the stream function technology. In this paper, we designed three kinds of phased array transmit coil with different ROI based on different clinical needs. The magnetic field intensity within the ROI reached higher than 0.957 4 A/m， the magnetic field homogeneity of 10 cm ROI was under 5×10^-8. The experimental results showed that the RF phased array coil designed using the inverse method met theory demands and was capable of used in MRI.
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Key words： MRI phased array coil inverse method regularization technology

基金资助:国家自然科学基金（61172034）

引用本文:

张战胜辛学刚^*. 反演法设计磁共振射频阵列线圈的研究[J]. 中国生物医学工程学报, 2012, 31(6): 822-830.
ZHANG ZhanSheng XIN XueGang^*. The Study on the Design of MR RF Phased Array Coil using Inverse Method. journal1, 2012, 31(6): 822-830.

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http://cjbme.csbme.org/CN/10.3969/j.issn.0258-8021.2012.06.004 或 http://cjbme.csbme.org/CN/Y2012/V31/I6/822

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