title: An ex vivo study on radiofrequency tissue ablation: increased lesion size by using an "expandable-wet" electrode.
abstract: The present comparative study was conducted to validate a newly developed "expandable-wet" electrode for an increased lesion size of radiofrequency ablation (RFA) on excised beef liver. The expandable-wet electrode, which allows interstitial hypertonic saline infusion through retractable curved needles, was compared with "expanded-dry" and "unexpanded-wet" electrodes for RFA lesion size and other parameters. A total of 120 lesions were created under 50 W (groups A-C) and 90 W (groups A'-C') power control mode for 10 min at each ablation site with the following groups: group A and A' of expanded-dry electrode (needles deployed but saline uninfused); group B and B' of unexpanded-wet electrode (saline infused but needle undeployed); and group C and C' of expanded-wet electrode (needles deployed and saline infused). Together with lower impedance and higher power output, the lesion size in group C (5.3+/-0.4 cm) and C' (6.0+/-1.0 cm) were significantly larger (P<0.01) than that in group A (3.3+/-0.3 cm) and A' (2.0+/-0.2 cm), and group B (3.8+/-1.0 cm) and B' (2.6+/-0.4 cm). The RFA lesion size can be significantly enlarged when the expandable electrode is complemented with interstitial hypertonic saline infusion. This design may improve the efficacy of RF tumor ablation.
authors.affiliation: Department of General Surgery, First Affiliated Hospital, Nanjing Medical University, Guangzhou Road 300, 210029 Nanjing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Miao
authors.forename: Y
authors.initials: Y
authors.lastname: Ni
authors.forename: J
authors.initials: J
authors.lastname: Yu
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: A
authors.initials: A
authors.lastname: Baert
authors.forename: G
authors.initials: G
authors.lastname: Marchal
mesh_terms: D000818:Animals; D002417:Cattle; D004566:Electrodes; D004867:Equipment Design; D006979:Hyperthermia, Induced / Q000295:instrumentation*; D066298:In Vitro Techniques; D008099:Liver / Q000473:pathology*