Translational Excitation Strategy for Scaled Transfer Function Measurement of Medical Implants

The transfer function (TF) of a medical implant is critical for radio frequency (RF)-induced heating evaluation during MRI scans. Conventionally, the calibration and validation of the TF are intertwined processes that rely on RF exposure experiments. This coupling can result in unvalidated scale factors and raise safety concerns for patients. To address this issue, we introduce the translational excitation strategy (TES), a method for independently measuring the scaled TF based on the principles of the induction and reciprocity theorems. TES allows the RF exposure experiment to serve as an independent validation step for the TF. We present both numerical simulations and experimental results to demonstrate the validity of this method. Moreover, TES enhances the efficiency of TF acquisition, offering a pioneering platform for advancing studies on the electromagnetic (EM) models of implants.