Use of Saline Coolant and Alumina to Facilitate Heat Transfer from Conductive Wires in Interventional MRI

Fabio Settecase¹, Anthony F. Bernhardt², Lee Evans², Vincent Malba², Alistair J. Martin¹, Mark Wilson¹, Steven Hetts¹

Microcoils can be used to steer catheter tips in the interventional MRI setting. Resistive heating due to currents necessary to achieve tip deflections, however, in addition to RF heating of conductive wires, can cause clinically significant temperature increases. This study investigates the use of alumina at the catheter tip to facilitate heat transfer to saline coolant flowing in the catheter lumen to mitigate temperature increases. The use of saline coolant and high heat conductivity material to facilitate heat dissipation are feasible strategies for other microcoil-catheter devices using nonferromagnetic conductive wires designed for interventional MRI.