A hybrid 2D-FDTD/3D-MoM method used for the analysis of MRI RF coils

Yang Liu; Qiuliang Wang; Feng Liu

doi:10.1016/j.mri.2023.11.005

A hybrid 2D-FDTD/3D-MoM method used for the analysis of MRI RF coils

Magn Reson Imaging. 2024 Feb:106:77-84. doi: 10.1016/j.mri.2023.11.005. Epub 2023 Nov 7.

Authors

Yang Liu¹, Qiuliang Wang², Feng Liu³

Affiliations

¹ Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
² Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: qiuliang@mail.iee.ac.cn.
³ School of Information Technology and Electrical Engineering, The University of Queensland, St. Lucia, Brisbane, Qld. 4072, Australia.

PMID: 37939971
DOI: 10.1016/j.mri.2023.11.005

Abstract

The design of radiofrequency (RF) coils is crucial for ultra-high field (UHF) magnetic resonance imaging (MRI) systems. To analyze RF coils, various numerical methods, such as finite-difference time-domain (FDTD) and method of moments (MoM), are usually adopted. In this paper, we present a novel hybrid approach that combines a two-dimensional (2D) FDTD with a three-dimensional (3D) MoM to analyze MRI RF problems. In our algorithm, the MoM is utilized for calculating the coil current, and FDTD is assigned for solving the electromagnetic (EM) fields in the imaging region. The hybrid method achieves superior efficiency and acceptable accuracy than using either method individually. To validate the hybrid method, we analyze an ellipse coil loaded with a uniform phantom and a realistic human head model, with the objective of tailoring the magnetic field intensity by adding a multilayer dielectric pad (DP). The results show an improvement in the magnetic field after optimizing the DP configuration. These simulation studies indicate the potential of the new numerical method for the design and analysis of RF systems for ultra-high field applications.

Keywords: Hybrid method; MRI; MoM; RF coil; Two-dimensional FDTD.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Algorithms*
Computer Simulation
Electromagnetic Fields
Equipment Design
Humans
Magnetic Resonance Imaging* / methods
Phantoms, Imaging
Radio Waves