The Effect of Thermal and Electrical Conductivities on the Ablation Volume during Radiofrequency Ablation Process

Abstract

Radiofrequency ablation (RFA) is the treatment of choice for certain types of cancers, especially liver cancer. However, the main issue with RFA is that the larger the tumor volume, the longer the ablation period. That causes more pain for the patient, so the surgeons perform a larger number of ablation sessions or surgeries. The current commonly used electrode material, nickel-titanium alloy, used in RFA is characterized by low thermal and electrical conductivities. Using an electrode material with higher electrical conductivity and thermal conductivity provides more thermal energy to tumors. In this paper, we design two models: a cool-tip RF electrode and a multihook RF electrode, which aim to study the effect of the thermal and electrical conductivities of the electrode material on ablation volume. Gold, silver, and platinum have higher thermal and electrical conductivity than nickel and titanium alloy, and therefore we studied the effect of these materials on the ablation volume using two different designs, which are the RF cooling tip electrode and the multi-hook electrode. The proposed model reduces the ablation time and damages healthy tissue while increasing the ablation volume with values ranging from 2.6 cm 3 to 15.4 cm 3 . The results show ablation volume increasing with materials characterized by higher thermal and electrical conductivities and thus reducing patient pain.

Numerical analysis of microwave and radiofrequency ablations: A novel design for electrode-based radiofrequency ablation

“…Consequently, an approximation treats the electromagnetic field as a quasistatic field. This approximation effectively describes the behavior using the Maxwell equations 34 :…”

“…Their results indicated that the volume of ablation increases with materials having higher electrical and thermal conductivities, leading to a reduction in ablation time and consequently minimizing patient discomfort. Metals such as gold, silver, platinum, and nickel-titanium have suitable thermal and electrical conductivities 34 . Today, nickel-titanium is used in RF electrodes 35 .…”