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Bipolar and Multipolar Radio Frequency Ablation With Resistance Controlled Power Output: Standardized Ex Vivo Kidney Tissue Evaluation

2006; Lippincott Williams & Wilkins; Volume: 175; Issue: 3 Linguagem: Inglês

10.1016/s0022-5347(05)00316-2

1527-3792

Axel Häcker, Stefan Vallo, Christel Weiß, Rainer Grobholz, Thomas Stein, Thomas Knoll, Maurice Michel,

Cardiac Arrhythmias and Treatments

No AccessJournal of UrologyInvestigative urology1 Mar 2006Bipolar and Multipolar Radio Frequency Ablation With Resistance Controlled Power Output: Standardized Ex Vivo Kidney Tissue Evaluation Axel Häcker, Stefan Vallo, Christel Weiss, Rainer Grobholz, Thomas Stein, Thomas Knoll, and Maurice Stephan Michel Axel HäckerAxel Häcker Department of Urology, Teltow, Germany , Stefan ValloStefan Vallo Department of Urology, Teltow, Germany , Christel WeissChristel Weiss Department of Biomathematics, Teltow, Germany , Rainer GrobholzRainer Grobholz Department of Pathology, Teltow, Germany , Thomas SteinThomas Stein All University Hospital Mannheim, Ruprecht-Karls University of Heidelberg, Heidelberg and Celon AG Medical Instruments, Teltow, Germany , Thomas KnollThomas Knoll Department of Urology, Teltow, Germany , and Maurice Stephan MichelMaurice Stephan Michel Department of Urology, Teltow, Germany View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)00316-2AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: We investigated a newly developed bipolar and multipolar RF ablation system with an internally cooled electrode and resistance controlled power output in a standardized model of perfused ex vivo kidney tissue. Materials and Methods: RF energy was applied at different power levels (20, 30 and 60 W) for 1, 3, 5 and 9 minutes. Each treatment parameter was repeated 5 times. For the 20/30 W levels a bipolar electrode with an active conducting part of 20/30 mm was selected. At 60 W 2 bipolar electrodes with an active conducting part (30 mm each) were connected. Lesion volumes and shapes were calculated by measuring the maximum vertical, long axis and short axis diameters of the macroscopic lesion. Results: Lesion volume increased significantly with the treatment time and generator power applied (p <0.0001). Lesion size in multipolar ablated zones was larger than that in bipolar ablated zones. A reliable dose-effect relationship existed between the generator power/applied treatment time and ablated tissue lesion size. All lesions were elliptical. Conclusions: Bipolar and multipolar RF ablation with an internally cooled electrode and tissue resistance control represent an interesting advance in RF technology. The development of lesion size and volume is predictable, while a uniform lesion shape can be achieved in perfused ex vivo kidney tissue. Further in vivo trials are required to test whether complete and reliable tumor tissue ablation is possible with this system. References 1 : The uncertainty of radio frequency treatment of renal cell carcinoma: findings at immediate and delayed nephrectomy. J Urol2002; 167: 1587. Link, Google Scholar 2 : Phase II trial of radio frequency ablation of renal cancer: evaluation of the kill zone. J Urol2002; 168: 2401. Link, Google Scholar 3 : Incomplete renal tumor destruction using radio frequency interstitial ablation. J Urol2002; 168: 2406. Link, Google Scholar 4 : Radiofrequency ablation: in vivo comparison of four commercially available devices in pig livers. Radiology2004; 232: 482. 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Google Scholar © 2006 by American Urological AssociationFiguresReferencesRelatedDetails Volume 175 Issue 3 March 2006 Page: 1122-1126 Advertisement Copyright & Permissions© 2006 by American Urological AssociationKeywordskidneysurgical proceduresminimally invasivecarcinomarenal cellcatheter ablationswineMetrics Author Information Axel Häcker Department of Urology, Teltow, Germany More articles by this author Stefan Vallo Department of Urology, Teltow, Germany More articles by this author Christel Weiss Department of Biomathematics, Teltow, Germany More articles by this author Rainer Grobholz Department of Pathology, Teltow, Germany More articles by this author Thomas Stein All University Hospital Mannheim, Ruprecht-Karls University of Heidelberg, Heidelberg and Celon AG Medical Instruments, Teltow, Germany More articles by this author Thomas Knoll Department of Urology, Teltow, Germany More articles by this author Maurice Stephan Michel Department of Urology, Teltow, Germany More articles by this author Expand All Advertisement PDF downloadLoading ...