Preechaphonkul W. and Rattanadecho P. , “The effects of dielectric & thermal property functions on the thermal response during the focused microwave ablation treatment in the liver cancer model: numerical investigation“, Engineered Science, 2022, Scopus, Q1 :
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Abstract
Radiofrequency Cardiac Ablation (RFCA) is a common procedure that heats cardiac tissue to destroy abnormal signal
pathways to eliminate arrhythmias. The complex multiphysics phenomena during this procedure need to be better
understood to improve both procedure and device design. A deformable poromechanical model of cardiac tissue
was developed that coupled joule heating from the electrode, heat transfer, and blood flow from normal perfusion
and thermally driven natural convection, which mimics the real tissue structure more closely and provides more realistic
results compared to previous models. The expansion of tissue from temperature rise reduces blood velocity, leading
to increased tissue temperature, thus affecting steam pop occurrence. Detailed temperature velocity, and thermal
expansion of the tissue provided a comprehensive picture of the process. Poromechanical expansion of the tissue
from temperature rise reduces blood velocity, increasing tissue temperature. Tissue properties influence temperatures,
with lower porosity increasing the temperatures slightly, due to lower velocities. Deeper electrode insertion raises
temperature due to increased current flow. The results demonstrate that a 5% increase in porosity leads to a considerable
10% increase in maximum tissue temperature. These insights should greatly help in avoiding undesirable heating
effects that can lead to steam pop and in designing improved electrodes.
