Fully MR‐guided hepatic artery catheterization for selective drug delivery: A feasibility study in pigs

Purpose To demonstrate the feasibility of hepatic catheterization for selective delivery of therapeutic agents using a clinical MRI scanner for real‐time image guidance. Materials and Methods Experiments were performed in three domestic pigs (70–80 kg) using a clinical 1.5‐T MR scanner. After abdominal three‐dimensional contrast‐enhanced MR angiography (3D‐CE‐MRA) was performed, endovascular devices with susceptibility markers were tracked with passive tracking techniques. Catheters were maneuvered into the primary and secondary hepatic arteries. Selective catheterization was verified using selective time‐resolved CE angiography. Paramagnetic microspheres were administered to a different region for each liver. The resulting biodistributions were investigated using MR images. Results Successful selective hepatic catheterization was repeatedly demonstrated using passive tracking techniques. 3D‐CE‐MRA significantly aided the interventional procedure by showing the vascular anatomy, and maximum‐intensity projections (MIPs) were used as roadmaps during the interventions. In all cases, microspheres were successfully delivered to the selected regions. The catheters were visualized at a maximum frame rate of five frames per second, allowing a good depiction of the devices and a reliable catheterization of the hepatic arteries. Conclusion Fully MR‐guided real‐time navigation of endovascular devices permits complex procedures such as selective intra‐arterial delivery of therapeutic agents to parts of the liver. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.