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
Purpose
Irreversible electroporation (IRE) is relatively novel method for percutaneous treatment of liver lesions. The major technological advancement is low heat production and independence of ablation shape and volume due to thermal lost. Thus IRE could be safely delivered to proximity of major hepatic vessels and bile ducts. Despite of these benefits there is few information about IRE used endoluminally in biliary tract (1).
Biliary metal stents are recommended only in malignant biliary obstruction with survival expectancy over 3 moths (2), frequently the patients survival exceed 12 months and more if patient is addressed to oncologic treatment. On the other hand patency rate of biliary metal stents is reported between 14 and 321 days (3). Therefore stent obstruction is a serious problem affecting quality of life, morbidity and mortality of patients undergoing palliative biliary procedures. Obstruction of metal stents is associated with epithelial hyperplasia, tumor ingrowth and overgrowth, dislocation, debris formation, and clot accumulation.
There are several methods how to treat and prevent biliary metal stent obstruction, but none of them showed satisfactory long-term results. Brachytherapy can be used for prevention of mucosal hyperplasia and tumor ingrowth before stent placement (4). Mechanical balloon cleaning is the simplest way of recanalization another solutions are stent in stent placement or endoluminal radiofrequency ablation. While metaanalysis did not show difference in survival or patency rate between metal and plastic stent used for treatment of biliary metal stent occlusion (5), balloon dilatation provides only temporary effect for mechanical obstruction by debris and it is unsuitable for other causes of stent obstruction. Endoluminal thermal ablation can be used for debulking and tumor growth deceleration, eventually for biliary metal stent recanalization, but it is unclear whether survival rate compared with plastic or metal stent will be improved (6). The usage of thermal ablation is limited in proximity to major vessels due to heat-sink effect and risk of bile duct injury in case of excessive heating. Endoluminal irreversible electroporation could surpass these drawbacks.
In the literature there are contradictory information, whether irreversible electroporation can or cannot be safely performed in proximity to metal stent (7). It rises a question if IRE could be performed endoluminally for cleaning of occluded bile ducts or biliary metal stent.
The goal of this experiment is to show feasibility of endoluminal IRE in partially obstructed metal stent using tubular IRE catheter. The secondary endpoint of the experiment is to clarify, whether the electrical parameters (impedance and current) measured during IRE procedure could precisely detect the interposed tissue.