From Low-Field to High Risk: Analyzing RF Heating of Neuromodulation and Cardiac Devices during MRI at 0.55T relative to 1.5T

Motivation: Radiofrequency-induced heating of elongated medical implants during MR imaging on newly introduced commercial 0.55T systems has not been thoroughly investigated. Goal(s): We aim to evaluate and compare the RF heating of elongated medical implants during MRI at 0.55T and 1.5T scanners. Approach: Neurological and cardiac implant leads were routed along different trajectories inside a tissue mimicking gel phantom, and the temperature increase during MRI at 0.55T and 1.5T was measured at the lead tip. Results: For certain implant configurations, RF heating at 0.55T MRI can be an order of magnitude higher than that at 1.5T. Impact: Our findings show that unsafe levels of RF heating, exceeding those at higher field strengths, are possible on commercial 0.55T MRI systems for certain implant configurations. Therefore, extra caution should be taken during low-field MRI of patients with long implants.