Keywords:
Not applicable, Experimental, Obstruction / Occlusion, Technical aspects, Recanalisation, Percutaneous, Oncology, Interventional non-vascular, Biliary Tract / Gallbladder, Interventional Radiology
Authors:
T. Rohan, T. Andrasina, T. Juza, P. Matkulcik, D. červinka, I. svobodova, V. Valek; Brno/CZ
DOI:
10.26044/ecr2020/C-05880
Results
Ex vivo part
Totally 72 IRE procedures in all scenarios were performed (10 in scenario A, 10 in scenario B, 31 in scenario C, 21 in scenario D). All scenarios with 300 a 650 V were successfully performed in the whole extent. Short circuit occurred at 1000 V in all cases in scenario B (both electrodes directly in contact with the metal stent, no inserted liver tissue) and in two of ten cases in scenario C (one active electrode in contact with the stent and the other with inserted liver tissue), because the current limit of the IRE generator was reached. The experiment was fully performed in only one case with 1300 V in scenario D, in this case macroscopic coagulation changes were observed. No macroscopic changes were visible during and after the procedure with voltages 300, 650 and 1000 V.
In scenario B stable resistance of 23 Ohm in 300 and 650 volts was observed, which represents resistance of the stent and electrodes, because no inserted liver tissue was present. Interposed tissue can be proved in the event of measured impedance over 50 Ohms.
Significant difference values of impedance and electric current between scenarios C and D were observed at 300, 650 and 1000 V (Mann-Whitney and Kruskal-Wallis ANOVA test).
Temperature changes are visualised in Fig. 3
In vivo part
In total 14 IRE (8 in scenario C and 6 in scenario D) procedures were performed and 13 liver tissue bands were left as controls. No complications during and on following CT examinations were observed.
Ten IRE procedures were successful in the whole extent. Detailed results are summarised in the table. Histopathological analyses revealed necrotic changes in 9 of 14 samples, where the most extensive necrotic areas were observed in scenario C at 650 V and in scenario D at 1000 V ( Fig. 4 ).
No necrosis was visible in control samples.