volume | PIER Journals

Abstract

Numerical methods based on solutions of Maxwell's equations are usually adopted for the electromagnetic characterization of Magnetic Resonance (MR) Radiofrequency (RF) coils. In this context, many different numerical methods can be employed, including time domain methods, e.g. the Finite-Difference Time-Domain (FDTD), and frequency domain methods, e.g. the Finite Element Methods (FEM) and the Method of Moments (MoM). We provide a quantitative comparison of performances and a detailed evaluation of advantages and limitations of the aforementioned methods in the context of RF coil design for MR applications. Specifically, we analyzed three RF coils which are representative of current geometries for clinical applications: a 1.5 T proton surface coil; a 7 T dual tuned surface coil; a 7 T proton volume coil. The numerical simulation results have been compared with measurements, with excellent agreement in almost every case. However, the three methods differ in terms of required computing resources (memory and simulation time) as well as their ability to handle a realistic phantom model. For this reason, this work could provide "a guide to select the most suitable method for each specific research and clinical applications at low and high field".

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Dr. Riccardo Stara

Dr. Nunzia Fontana

Dr. Gianluigi Tiberi

Dr. Agostino Monorchio

Dr. Giuliano Manara

Dr. Maria Alfonsetti

Dr. Angelo Galante

Dr. Assunta Vitacolonna

Dr. Marcello Alecci

Dr. Alessandra Retico

Dr. Michela Tosetti