title: Enlargement of thermal ablation zone by the combination of ethanol injection and radiofrequency ablation in excised bovine liver.
abstract: The efficacy of radiofrequency ablation (RFA) and RFA with concurrent ethanol injection (EI-RFA) was compared. RFA (3-cm-electrode) was applied to bovine liver using three types of RFA equipment; Radionics, RITA and Radio Therapeutics Corporation (RTC). For EI-RFA, 5 ml of 99.5% ethanol was injected around the electrode. A total number of 40 RFA and EI-RFA treatments were performed. We compared RFA with EI-RFA by examining the size, shape of ablation zone, treatment time, power, and needle tip temperature. Liver specimens were examined for pathological changes. EI-RFA produced a larger zone of ablation than RFA alone using Radionics and RITA (Radionics, 35.3+/-7.4 cm(3) vs 23.2+/-7.7 cm(3), p<0.05; RITA, 30.7+/-10.3 cm(3) vs 19.7+/-4.7 cm(3), p<0.05), corresponding to shortest diameters of coagulation zone (Radionics, 3.7+/-0.4 cm vs 3.0+/-0.4 cm, p<0.05; RITA, 3.8+/-0.4 cm vs 3.1+/-0.3 cm, p<0.01). However, a larger ablation zone was not seen with the RTC device. The ablated volume per energy and the ablated volume per current density administered were greater with EI-RFA than with RFA using Radionics (p<0.05). The shape of the ablated zone changed from ellipsoid to spherical with EI-RFA using Radionics. No pathological differences between RFA and EI-RFA samples were detected. For a given amount of energy and current administered, ethanol injection caused a better ablation effect, in terms of the size and shape of the ablated zone, than RFA with Radionics and RITA equipment.
authors.affiliation: Third Department of Internal Medicine, Kagawa University School of Medicine, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
authors.forename: Seishiro
authors.initials: S
authors.lastname: Watanabe
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Kurokohchi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Masaki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Miyauchi
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Funaki
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Inoue
authors.forename: Takashi
authors.initials: T
authors.lastname: Himoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kita
authors.forename: Naohito
authors.initials: N
authors.lastname: Uchida
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Touge
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Tatsukawa
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kuriyama
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D017115:Catheter Ablation / Q000379:methods*; D002417:Cattle; D004566:Electrodes; D000431:Ethanol / Q000494:pharmacology*; D006358:Hot Temperature; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology* / Q000528:radiation effects*; D013696:Temperature; D013997:Time Factors
chemical_list: D000891:Anti-Infective Agents, Local; D000431:Ethanol