Feasibility of Active Cable Trap to Attenuate MRI-Induced RF Currents

Marta Gaia Zanchi¹, John Mark Pauly¹, Greig Cameron Scott¹

We present a feasibility of active cancellation of unsafe RF guidewire currents induced during an MRI scan. Toward this goal, we have designed and built a prototype "active cable trap" based on Cartesian feedback and used it to demonstrate over 30 dB attenuation of RF wire currents on the bench. If the wire tip were in contact with tissue, this is equivalent to a 1000x reduction of heating by currents induced by RF fields. In comparison to passive cable traps and Q-spoiling loads, our newly developed active cable trap should not suffer from component loss and tuning interactions with wires.