Christian Rosenberg MD, Presenter: Nothing to Disclose

Christiane Weigel MD, Abstract Co-Author: Nothing to Disclose

Norbert Hosten MD, Abstract Co-Author: Nothing to Disclose

To evaluate efficacy and advantages of a new MRI-compatible probe for radiofrequency ablation (RFA) of primary and secondary liver malignancies. CT for needle placement can not be used if lesions are not seen on plain CT.

RFA was performed using a 17 G saline-cooled single probe (Cool-tip©, Radionics). Optimal conditions for cooling, energy and ablation time were retrieved testing the system in porcine liver. Patients were strictly evaluated for insufficient CT imaging. 19 Patients received ablative therapy in a standardized manner. Percutaneous insertion and therapy monitoring were performed in a closed high-field scanner using breath-hold T1-weighted GRE sequences.

Lesions were well visualized on plain or contrast-enhanced MRI. Ablation time of 15 minutes and energy elevation to a maximum 200 W were found suitable to achieve safe and sufficient ablation of targeted malignant tissue. Maximal induced coagulative necrosis was 15.7 ccm in a single application. Lesion ablation was technically and clinically successful. Miniaturized design and surface profile of the application probe benifited its handling. The needle was well visualized in TRUEFISP and 2dFLASH sequences with minimal imaging artifacts not limiting the intervention.

MRI-guided RFA of liver malignancies is a safe and feasible procedure in an interdisciplinary multimodal cancer therapy. Advantages are evident for lesions not seen on plain CT. Probe insertion and therapy can be performed in one setting using a single imaging modality. Safety and feasibility of critical positioning maneuvers are increased using multiplanar imaging.

Rosenberg, C, Weigel, C, Hosten, N, Percutaneous Ablation of Hepatic Malignancies: Insertion of an MRI-compatible Radiofrequency Probe.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4417127.html