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Abstract #3457

Optimized Transmit Pulses for Excellent Whole-Brain Excitation Homogeneity in High Field MRI

Tingting Shao1, Ling Xia1, Feng Liu2, Stuart Crozier2

1Biomedical Engineering, Zhejiang University, Hangzhou, Zhejiang, China; 2School of Information Technology & Electrical Engineering, University of Queensland, Brisbane, Australia

This work presents a novel approach for designing RF pulses to achieve excellent whole-brain excitation homogeneity in high field MRI. Based on the parallel transmission technology, an optimized 3D tailored RF (TRF) pulse has been proposed to account for the severe RF(B1) inhomogeneity at 11.7T. The pulse is designed with an adaptive stack-spiral trajectory tailored according to the trajectory container, whose interior is mostly responsible for the desired excitation pattern. An iterative RF pulse design method is employed to ensure the excitation accuracy. Test simulations show that the proposed scheme provides homogeneous excitation over the entire brain volume in spite of the inhomogeneous field and insufficient longitudinal coverage.

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Keywords

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