Performance evaluation and comparison of two triple-nuclear RF resonators for ¹H/¹⁹F/³¹PMR imaging at 9.4T

Radio frequency (RF) coils are critical devices in magnetic resonance (MR) systems for transmitting and receiving magnetic resonance signals. However, the required high operating frequency at ultrahigh magnetic fields makes the design of highly efficient radio frequency (RF) transmit or receive coils technically challenging. This is particularly true in the double-tuned or triple-tuned RF coils usually required in heteronuclear MRI and MRS where multiple nuclei, such as ¹H, ¹⁹F, and ³¹P, are involved. The performance of RF coils is a critically important factor for realizing the high sensitivity provided by ultrahigh magnetic fields to contribute towards the advancement of a novel human in vivo application at 9.4T. In this work, two different configurations of novel triple-nuclear (¹H/¹⁹F/³¹P) RF resonators were proposed for the ultrahigh field 9.4T applications. We also reported on the design and construction, and a field-circuit co-simulation was used to obtain the S-parameters, B₁⁺ field and specific absorption rate (SAR) distributions to evaluate and compare their performance. And the characteristics and advantages of the proposed two different configurations of triple-nuclear RF resonators in the applications of ¹H/¹⁹F/³¹P at ultrahigh magnetic field were investigated.