The aim of the course is to give an in-depth introduction to the numerical computation of radio-frequency (RF) fields in magnetic resonance (MR) systems. Main focus will be the application to RF coil design and patient safety. After the course, participants will be able to solve typical MR-related field problems with suitable numerical methods and corresponding models, to interpret the calculated field distributions, and to perform appropriate post-processing procedures to characterise multi-channel RF transmit coils and to assess the RF safety of patients/volunteers under consideration of common exposure scenarios.
The course is intended for MR physicists, engineers, other scientists, and PhD students who either wish to start working in the field of RF coil development and/or RF exposure or who already have basic to intermediate experience in RF simulation.
The course programme includes modules with theoretical lectures, practical exercises as well as hands-on training on commercial simulation platforms. Lectures will prepare the fundamentals for successful application of numerical simulation and will start with selected topics of electromagnetic theory followed by an introduction to numerical methods. To derive appropriate numerical models and implementations of post-processing routines, lectures on RF coil design and characterisation as well as on common approaches to assess the RF exposure and RF safety of implants under consideration of current RF safety guidelines will be given. Further, methods for the validation of the calculated field distributions will be presented. During the practical exercises, the participants will deepen the subject matter of the lectures individually by solving fundamental problems. Under guidance of the faculty, the application of numerical methods and the adjustment of important simulation parameters with respect to the chosen method will be explained. During the course, software vendors will give an introduction to their simulation software and will present advanced application examples. For the practical exercises and hands-on training, desktop PCs will be provided for the participants.
Material properties, biological tissue
Conservation of energy – power balance
Quasi-static approximation (Biot-Savart law)
Basics of the solution in time and frequency domain
Introduction to local methods
Finite-difference method/Finite integration method in time domain
Finite element method
Integral equation methods
RF field measurements
Realistic phantom design and characterisation
Correlating simulations and measurements quantitatively
RF coil design and characterisation
Stripline based elements
Multi-channel transmit arrays
Transmission mode: B1+-efficiency, SAR
Receive mode: SNR, g-factor/-maps
RF safety and guidelines
Exposure aspects and corresponding SAR and temperature limits
SAR evaluation and monitoring for multi-channel transmit