A Simulation Study on the Effect of the High Permittivity Materials Geometrical Structure on the Transmit Field B+1 at 1.5 T

Recent studies show that high permittivity materials (HPMs) have great application prospects in improving the performance of RF coils and enhancing magnetic resonance image signal to noise ratio (SNR) in high and ultra-high field magnetic resonance imaging (MRI). So far the research about HPMs mainly focuses on its benefit for MRI image SNR, while investigation on how its geometrical structure affects the homogeneity of transmit field (B+1) is insufficient. In this study the effect of the geometrical structure of HPMs on the average transmit efficiency and B+1 inhomogeneity at 1.5 T was quantitatively analyzed through electromagnetic simulation. The results indicated that for the four investigated geometrical structures of HPMs the quartered cylinder is the optimum solution, which would be valuable for the application of HPMs in MRI.