A counterpoise design for RF-induced heating reduction

This paper presents a novel lead body design for active implantable medical devices (AIMD) to reduce Radio-frequency (RF) induced heating during magnetic resonance imaging (MRI) scanning. By introducing a counterpoise electrode to the original lead construct, part of the RF-induced energy can be decoyed into the surrounding tissues while the therapy signal is intact. The numerical simulation studies of three leads with different configurations are presented to demonstrate the effectiveness of this technique. From simulation results at 1.5 T, the peak 1g average SAR value can be reduced by a factor of 3 when the length of the counterpoise electrode is properly designed.