Experimental radiofrequency ablation near the portal and the hepatic veins in pigs: differences in efficacy of a monopolar ablation system

BACKGROUND: We sought to compare the efficacy of a monopolar radiofrequency ablation system in vivo near the portal vein and the hepatic veins in porcine liver. MATERIALS AND METHODS: Radiofrequency ablation of healthy livers near the portal vein and the hepatic veins was performed in 10 pigs with a multitined expandable electrode. Volumes and diameters of zones of ablation were assessed by magnetic resonance imaging. RESULTS: Volumes (16.0 +/- 5.5 mL, P = 0.001) and diameters (4.0 +/- 0.7 cm, 3.3 +/- 0.7 cm, 3.0 +/- 0.6 cm, P