Numerical Prediction of Temperature Elevation Induced Around Metallic Hip Prostheses by Traditional, Split and Uniplanar Gradient Coils

Purpose: 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. Methods: 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. Results: Several exposure situations obtained by changing the patient’s position are analyzed, finding temperature elevations on the order of some degrees. Conclusion: 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.