Multimode intravascular RF coil for MRI‐guided interventions

Purpose: To demonstrate the feasibility of using a single intravascular radiofrequency (RF) probe connected to the external magnetic resonance imaging (MRI) system via a single coaxial cable to perform active tip tracking and catheter visualization and high signal‐to‐noise ratio (SNR) intravascular imaging. Materials and Methods: A multimode intravascular RF coil was constructed on a 6F balloon catheter and interfaced to a 1.5T MRI scanner via a decoupling circuit. Bench measurements of coil impedances were followed by imaging experiments in saline and phantoms. Results: The multimode coil behaves as an inductively coupled transmit coil. The forward‐looking capability of 6 mm was measured. A greater than 3‐fold increase in SNR compared to conventional imaging using optimized external coil was demonstrated. Simultaneous active tip tracking and catheter visualization was demonstrated. Conclusion: It is feasible to perform 1) active tip tracking, 2) catheter visualization, and 3) high SNR imaging using a single multimode intravascular RF coil that is connected to the external system via a single coaxial cable. J. Magn. Reson. Imaging 2011;33:995–1002. © 2011 Wiley‐Liss, Inc.