Radiofrequency (RF) coils are used to transmit and receive signals in magnetic resonance (MR) systems. Optimized RF coil design has to take into account strategies to maximize the coil performance by choosing coil sizes and geometry for achieving the best signal-to-noise ratio (SNR). In particular, coil conductor and radiative loss contributions strongly affect the SNR value, with the first mainly playing a role in low-field MR systems especially, while the second could be the dominant coil loss mechanism for high-frequency tuned coils.
This paper investigates the accuracy of the finite-difference time-domain (FDTD) method for separately estimating coil conductor and radiative loss contributions. Completing what is described in the literature regarding the sample-induced resistance estimation, it is demonstrated that FDTD is very effective in estimating complete performance of MRI coils. In this work, FDTD results were compared with analytical and FEM ones and with workbench measurements performed on a surface RF coil prototype, demonstrating the accuracy of the FDTD method in separately estimating conductor and radiation losses in RF coils and indicating a great potential to simulate complicated coil designs that lack analytical formulas to model the losses.
Giovannetti G, Wang Y, Jayakumar NKT, Barney J, Tiberi G. Magnetic Resonance Wire Coil Losses Estimation with Finite-Difference Time-Domain Method. Electronics. 2022; 11(12):1872. https://doi.org/10.3390/electronics11121872