Numerical prediction of temperature elevation induced around metallic hip prostheses by traditional, split, and uniplanar gradient coils.

Abstract

The paper presents a computational study for the estimation of the temperature elevation occurring in a human subject carrying metallic hip prostheses when exposed to the magnetic field produced by gradient coils. The simulations are performed through validated numerical codes, which solve the electromagnetic and thermal equations applied to a high-resolution anatomical human model. Three different sets of gradient coils (traditional, split and uniplanar) are considered to evaluate the maximum steady-state temperature elevation in the human body. This result is then rescaled to take into account the waveform of the signal, the duty-cycle and the duration of the scan. Several exposure situations obtained by changing the patient's position are analyzed, finding temperature elevations on the order of some degrees. The results are of possible concern and provide evidence of the need for further specific investigations aimed at assuring the safety of potential patients carrying metallic hip implants. Magn Reson Med 74:272-279, 2015. © 2014 Wiley Periodicals, Inc.