Combined use of the intravascular blood-pool agent, gadomer, and carbon dioxide: A novel type of double-contrast magnetic resonance angiography (MRA)

Purpose To evaluate the combined use of carbon dioxide (CO2) and a gadolinium‐based blood‐pool agent for magnetic resonance angiography (MRA). Materials and Methods After an initial intravenous injection of the blood‐pool agent Gadomer (Schering AG, Germany), repeated transcatheter CO2 injections were performed in the aorta and the renal arteries of two fully‐anesthetized pigs. Real‐time images were acquired using a true fast imaging with steady‐state precession (FISP) sequence. Results During the CO2 injections, the Gadomer‐enhanced blood was totally replaced, resulting in an immediate, temporary, total signal loss in the vessel lumen. Susceptibility artifacts during the injections or catheter manipulations rarely occurred. Conclusion Due to T1‐shortening, the circulating blood‐pool agent prevents flow artifacts during catheter manipulations because the steady‐state is reached much earlier. Therefore, this double‐contrast MRA method improves catheter conspicuity and might be helpful for guiding and controlling intravascular procedures during interventional MRI. J. Magn. Reson. Imaging 2005;21:645–649. © 2005 Wiley‐Liss, Inc.