MRI aided monitoring of (biodegradable) passively conducting implants is challenged by transmission field inhomogeneities and potential elevation of RF power deposition (SAR) in the vicinity of an implant. Small movements of an implant with respect to the RF transceiver constitute another potential risk factor for clinical MRI. Recognizing this challenge and the opportunities, this work uses a multi-objective genetic algorithm (GA) to examine the feasibility of excitation vector optimized parallel transmission in the presence of small variations in implant position/orientation. The GA approach provided excitation vectors that meet the safety guidelines for SAR in close vicinity of a (biodegradable) passively conducting implant and that are immune to small changes in the relative position between the implant and the RF transceiver. Our findings are not limited to the specific implant configurations and experimental setups used in this study but provide the technical foundation to derive a generalized transfer function.
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