FDTD simulation of RF coils for MRI

Magnetic resonance imaging, or MRI, is a valuable diagnostic tool in modern medicine. Among the key elements of the MRI instrumentation are highly resonant LC radio frequency (RF) coils, which consist of conducting wires and capacitors. The coils are used as either stand alone surface coils, or they can be coupled together in a resonant configuration known as a "bird cage." The loop inductance is provided by the wires and depends on the geometry of the loop as well as the cross-section of the wire. This paper describes the use of the finite-difference time-domain (FDTD) method in simulating the RF coils. In particular, we evaluate the ability of the method to correctly determine the inductance provided by the wire.