RF ablation thermal simulation model: Parameter sensitivity analysis.

Area of Science:

• Biomedical Engineering
• Medical Physics
• Computational Modeling

Background:

• Temperature-controlled radiofrequency ablation (RFA) is a key treatment for liver tumors.
• Understanding the impact of tissue electro-thermal properties is crucial for optimizing RFA efficacy.
• Parameter sensitivity analysis can elucidate critical factors influencing RFA outcomes.

Purpose of the Study:

• To quantify the relative influences of key electro-thermal parameters on ablation temperature and lesion volume during RFA of liver tumors.
• To provide a basis for specificity analysis in RFA computational models.

Main Methods:

• A finite element method (FEM) model was developed to simulate the RFA temperature field.
• Sensitivity analysis was performed on six tissue parameters: thermal specific capacity (Cp), thermal conductivity (k), electrical conductivity (Sigma), density (rho), dielectric constant (Epsilon), and resistance (R).
• Simulations were executed using Comsol Multiphysics, with sensitivity determined by variance contribution rate (SS%) or main effects.

Main Results:

• Increased electrical conductivity (Sigma) and resistance (R) led to higher ablation temperatures and larger lesion volumes.
• Elevated thermal specific capacity (Cp) and density (rho) resulted in decreased ablation temperature and lesion volume.
• Thermal conductivity (k) had a minor effect on lesion volume, while the dielectric constant (Epsilon) showed a negligible impact on ablation temperature.

Conclusions:

• The study identified critical electro-thermal parameters significantly affecting RFA outcomes in liver tumors.
• These findings offer a reliable reference for enhancing the specificity and accuracy of RFA computational models.
• Sensitivity analysis is a valuable tool for understanding complex interactions in RFA simulations.