Saline-enhanced RF ablation on a cholangiocarcinoma: a numerical simulation
Purpose - Cholangiocarcinoma is an adenocarcinoma of the bile ducts which drain bile from the liver into the small intestine. Unfortunately, most patients are diagnosed at an advanced stage of the disease with almost no chances for surgery, the only potentially curative treatment. As nitinol stents can be used to reduce stricture problems of the bile duct, these can be also considered as potential electrodes for hyperthermia treatments. Previous works show that, in fact, these metallic stents might be used as part of a feasible solution for delivering radiofrequency (RF) energy into a tumor located in a hollow organ to destroy the tumor tissue. However, the tissue lesion induced is not completely uniform due to convective heat transfer associated to the blood flow in the nearby vessels. The purpose of this paper is to study the use of saline solution for modifying the electrical conductivity of the tissue in order to obtain a more uniform lesion. Design/methodology/approach - A numerical analysis using finite element method on a simplified model of the porta hepatis is performed. The tumor tissue is divided in three sections and simulations were performed considering a higher electrical conductivity in the middle section of the tumor, imitating the presence of a saline solution in this part of the tissue. Findings - Results show that it is possible to obtain a more regular volume, by the way the tumor tissue is preferentially heated, although there are still some risks on exceeding the dimension of the bile duct. Originality/value - This study presents the numerical analysis of a saline-enhanced RF tissue thermoablation of a cholangiocarcinoma considering a stent-based electrode. Results point to the possibility of obtaining a more regular volume of damaged tissue in order to heat and preferentially destroy the tumor tissue.
numerical simulation diseases electrical conductivity stent-based electrodes body systems and organs histology radiofrequency ablation self-expandable metallic stents saline-enhanced rfa hyperthermia therapy