Ex vivo evaluation of a bipolar application concept for radiofrequency ablation.
BACKGROUND
Bipolar radiofrequency ablation (RFA) can avoid complications such as thermal tissue damage, a possible consequence of monopolar RFA. However, basic studies about the dosage/effect relationship of bipolar systems are missing. This is systematic research on ex vivo beef livers to find which capacity parameters produce high energy in the tissue and achieve large lesion volumes.


METHODS
The active lengths 20, 30 and 40 mm of a bipolar, internally cooled applicator were studied. The tissue was fresh ex vivo beef liver. Five measurements each for each active applicator with a power between 10 and 50 W were conducted.


RESULTS
The best power for the 20 mm applicator was 15 W, since the highest achieved volume was 5,599+/-1,760 mm(3) and the highest amount of energy introduced to the tissue was 15+/-3 kJ. The best power for the 30 mm applicator was 20 W (volume 14,538+/-1,220 mm(3), energy 24+/-1 kJ). For the 40 mm applicator, the best power was 20 W, (volume 20,562+/-896 mm(3), energy 24+/-0 kJ).


CONCLUSIONS
The results of this study help clinicians determine which active length is required for the applicator and which presetting should be selected to achieve a defined coagulation volume size.
Department of General, Vascular and Thoracic Surgery, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany. urte.zurbuchen@charite.de
Urte
U
Zurbuchen
Bernd
B
Frericks
André
A
Roggan
Kai
K
Lehmann
Daniela
D
Bössenroth
Heinz-J
HJ
Buhr
Jörg-Peter
JP
Ritz
D000818:Animals; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D002417:Cattle; D003080:Cold Temperature; D004566:Electrodes; D008099:Liver / Q000473:pathology / Q000601:surgery*; D008102:Liver Circulation; D011846:Radio Waves