OBJECTIVES: A standardized perfused ex vivo bovine liver model was used to evaluate the effect of organ perfusion on coagulation size and energy deposition during radiofrequency ablation (RFA) procedures. MATERIALS AND METHODS: Bovine livers were perfused in a tank after rinsing the prepared liver vessels with anticoagulants. Tyrode's solution, oxygenated and heated to 36.5 degrees C, was used as perfusion medium. A flow and pressure controlled pump regulated Portal vein circulation; a dialysis machine provided pulsatile arterial circulation. Impedance-guided radiofrequency ablations were performed with 4-cm LeVeen electrodes with and without underlying liver perfusion. Two-dimensional diameters (Dv, Dh) of each ablation area were measured after dissecting the livers. RESULTS: In 4 bovine livers weighing 8.85 +/- 0.83 kg per organ (min, 7.7 kg; max, 9.7 kg) altogether 40 RF ablations were performed. A total of 20 ablations were generated with underlying liver perfusion (group 1) and 20 ablations with no liver perfusion (group 2). In group 1, Dv was 28.4 +/- 5.3 mm, Dh 38.6 +/- 7.8 mm, and energy deposition 36.9 +/- 18.0 kJ. The 20 ablation areas generated without liver perfusion displayed statistically significant differences, with Dv being 35.7 +/- 6.5 mm (P = 0.001), Dh 49.5 +/- 9.4 mm (P = 0.001), and energy deposition 25.5 +/- 13.0 kJ (P = 0.018). CONCLUSION: The model reproduced the cooling effect of perfused tissue during RFA. The ablation areas produced under perfusion conditions had smaller diameters despite longer exposure times and higher energy deposition.
OBJECTIVES: A standardized perfused ex vivo bovine liver model was used to evaluate the effect of organ perfusion on coagulation size and energy deposition during radiofrequency ablation (RFA) procedures. MATERIALS AND METHODS:Bovine livers were perfused in a tank after rinsing the prepared liver vessels with anticoagulants. Tyrode's solution, oxygenated and heated to 36.5 degrees C, was used as perfusion medium. A flow and pressure controlled pump regulated Portal vein circulation; a dialysis machine provided pulsatile arterial circulation. Impedance-guided radiofrequency ablations were performed with 4-cm LeVeen electrodes with and without underlying liver perfusion. Two-dimensional diameters (Dv, Dh) of each ablation area were measured after dissecting the livers. RESULTS: In 4 bovine livers weighing 8.85 +/- 0.83 kg per organ (min, 7.7 kg; max, 9.7 kg) altogether 40 RF ablations were performed. A total of 20 ablations were generated with underlying liver perfusion (group 1) and 20 ablations with no liver perfusion (group 2). In group 1, Dv was 28.4 +/- 5.3 mm, Dh 38.6 +/- 7.8 mm, and energy deposition 36.9 +/- 18.0 kJ. The 20 ablation areas generated without liver perfusion displayed statistically significant differences, with Dv being 35.7 +/- 6.5 mm (P = 0.001), Dh 49.5 +/- 9.4 mm (P = 0.001), and energy deposition 25.5 +/- 13.0 kJ (P = 0.018). CONCLUSION: The model reproduced the cooling effect of perfused tissue during RFA. The ablation areas produced under perfusion conditions had smaller diameters despite longer exposure times and higher energy deposition.
Authors: K S Lehmann; J P Ritz; S Valdeig; V Knappe; A Schenk; A Weihusen; C Rieder; C Holmer; U Zurbuchen; P Hoffmann; H O Peitgen; H J Buhr; B B Frericks Journal: Langenbecks Arch Surg Date: 2009-03-10 Impact factor: 3.445
Authors: Kai Siegfried Lehmann; Bernd Benedikt Frericks; Christoph Holmer; Andrea Schenk; Andreas Weihusen; Verena Knappe; Urte Zurbuchen; Heinz Otto Peitgen; Heinz Johannes Buhr; Jörg Peter Ritz Journal: Int J Colorectal Dis Date: 2011-03-15 Impact factor: 2.571
Authors: R Wahba; C Bangard; R Kleinert; S Rösgen; J-H Fischer; K-J Lackner; A H Hölscher; D L Stippel Journal: Langenbecks Arch Surg Date: 2009-03-14 Impact factor: 3.445
Authors: Krishna Pillai; Javid Akhter; Terence C Chua; Mena Shehata; Nayef Alzahrani; Issan Al-Alem; David L Morris Journal: Medicine (Baltimore) Date: 2015-03 Impact factor: 1.889