| Autor: |
H. J. Buhr, Andrea Schenk, P. Hoffmann, J. P. Ritz, Bernd Frericks, K. S. Lehmann, Verena Knappe, S. Valdeig |
| Rok vydání: |
2009 |
| Předmět: |
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| Zdroj: |
Deutsche Gesellschaft für Chirurgie ISBN: 9783642006241 |
| DOI: |
10.1007/978-3-642-00625-8_35 |
| Popis: |
Objective: During RF ablation of liver tumours it is a risk of incomplete tumor areas along the liver vessels. Up to now, there is no systematically analysis of the influence of vessel diameter and flow velocity on the intensity of heat dissipation during therapy available. The objective of this study was to quantify this cooling effect in an ex vivo model. Methods: In our experimental setup with fresh porcine liver we used a bipolar applicator with 30W output power and 15 kJ energy. For the simulation of different vessel diameters, glass tubes with different diameters (di=1.0–8.0 mm) were inserted. The distance between RF applicator and glass tubes was 5 mm. For the simulation of different flow velocities, for the glass tube with diameter di=3,4 mm we varied the flow velocity from 0–917.35 mms−1. After the ablation, the dimensions of the resulting lesion were digitally measured. Results: 144 lesions were induced in 48 porcine livers with 6 repetitions for each parameter setting. In the results for the different vessel diameters, there is no significant difference between the lesion sizes. But the flow velocities are clearly influencing the lesion size. Already with a flow of 1.84mms−1 we could measure a significant area reduction of 16.2% compared to zero flow, which stepped up to 33.6% area reduction for 917.35 mms−1 flow velocity. Conclusion: In a standardised ex vivo model could be shown, that the main influence is not the vessel diameter but rather the blood flow. Even for low flow rates, the heat reduction is enough to significantly reduce the lesion size. These results could be helpful for clinical therapy planning when the tumor is close to liver vessels with significant blood flow. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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