Abstract：The multi-channel array coil has been widely applied in MRI to improve the quality of images in recent years. Aimed at optimizing the radio frequency (RF) field in the local region of interest (ROI), we proposed a model of a 6-channel array coil consisting of elements of different dimensions, which was proved to be able to optimize the RF field in the local region of interest in the pelvic cavity. The model was made up of coils with two different widths (10 cm and 20 cm). In this paper, geometry overlapping and capacitive network methods were adopted to decouple coils, and the finite difference time domain (FDTD) method was applied to simulation and calculation. The RF field in ROI produced by the proposed array coil was analyzed and evaluated. The simulation results showed that the decoupling levels S12 and S13 of the proposed array coil combined with the elliptic cylinder electromagnetic model were -27.19 dB and -33.46 dB, respectively. Additionally, the RF field B+1 mean value in ROI was approximately 5.21% larger than a conventional array coil made up of same elements with width of 15 cm. In conclusion, the array coil made up of elements with different dimensions improved the RF field in ROI, thereby providing inspiration for the design of RF coils for MRI.
李华勇, 曹双亮, 王沛沛, 陈美玲, 路利军, 陈武凡. 磁共振六通道线圈阵列的数字化仿真与设计[J]. 中国生物医学工程学报, 2017, 36(6): 711-717.
Li Huayong, Cao Shuangliang, Wang Peipei, Chen Meiling, Lu Lijun, Chen Wufan. The Numerical Simulation and Design of a 6-Channel Array Coil for MRI. Chinese Journal of Biomedical Engineering, 2017, 36(6): 711-717.
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