Accurate FDTD Simulation of RF Coils for MRI Using the Thin-Rod Approximation

The finite-difference time-domain (FDTD) method is being used in the design and analysis of highly resonant radio frequency (RF) coils often used for magnetic resonance imaging (MRI). It is shown that by using the thin-rod approximation (TRA) for accurate wire radius calculation, the FDTD method can model the inductance of the metal wires for different radii at radio frequencies, as well as the capacitance of discrete elements. FDTD can also model human bodies in the near field of the loop in order to determine the influence of the body on the loop, as well as the heating patterns produced in the body by the electromagnetic radiation.