Towards MRI-Safe Implanted Leads: A Comparative Evaluation of Four Designs

Paul A. Bottomley¹, William A. Edelstein¹, Ananda Kumar¹, Justin M. Allen¹, Perry Karmarkar¹

Implanted leads and devices are a contraindication for MRI, denying many patients its potential benefits. Here, the MRI safety of four passive implantable lead designs that minimize the hazards of induced currents and heating, is investigated as a function of geometry. Continuously coiled leads, leads incorporating RF traps, and single and multi-layer billabong leads with reversed sections wherein the current opposes the induced RF, are compared in a model phantom at 1.5T and 4W/kg exposure. In coil and trap designs factors that maximize impedance limited heating below 1-2C, but folded lead configurations can be problematic. The billabong designs heated <1C.