Wireless Resonant Circuits Printed Using Aerosol Jet Deposition for MRI Catheter Tracking

Interventional magnetic resonance imaging could allow for diagnosis and immediate treatment of ischemic stroke; however, such endovascular catheter-based procedures under MRI guidance are inherently difficult. One major challenge is tracking the tip of the catheter, as standard fabrication methods for building inductively coupled coil markers are rigid and bulky. Here, we report a new approach that uses aerosol jet deposition to 3D print an inductively coupled RF coil marker on a polymer catheter. Our approach enables lightweight, conforming markers on polymer catheters and these low-profile markers allow the catheter to be more safely navigated in small caliber vessels. Prototype markers with an inductor with the geometry of a double helix are incorporated on catheters for $in vitro$ studies, and we show that these markers exhibit good signal amplification. We report temperature measurements, and finally demonstrate feasibility in a preliminary $in vivo$ experiment. We provide material properties and electromagnetic simulation performance analysis. This work presents fully aerosol jet-deposited and functional LC circuits on polymer catheters for use in 3T clinical scanners.