Lithography based resonant marker design for MRI catheter visualization

Background The unavailability of safe, conspicuous devices remains the chief barrier to wider clinical adoption of interventional cardiovascular magnetic resonance imaging. Active catheter receiver coils are conspicuous but their metallic transmission lines risk heating and their manufacture requires excessive device size. We have designed a clinical grade 5 Fr radio frequency (RF) resonator marker embedded directly into the catheter shaft using novel lithography techniques. We developed special manufacturing techniques to impart these circuits onto non-planar catheter surfaces. This approach eliminates (1) the bulky circuit components such as wire-wound coils and rigid capacitors as well as (2) long conductive cables, required for receiver coil-based visualization, that are subject to heating.