Transient changes during microwave ablation simulation : a comparative shape analysis

Area of Science:

• Biomedical Engineering
• Medical Physics
• Computational Modeling

Background:

• Microwave ablation therapy uses heat to destroy cancerous tumors.
• Predictive modeling is crucial for optimizing ablation treatment outcomes.

Purpose of the Study:

• To investigate changes in temperature and specific absorption rate (SAR) fields during simulated microwave ablation.
• To compare the performance of different microwave ablation probe designs.

Main Methods:

• Developed an axisymmetric model of a probe within tissue.
• Solved coupled electromagnetic and bioheat equations using the finite element method (FEM) with hp discretization.
• Utilized the NGSolve library for simulations.

Main Results:

• Observed dynamic changes in temperature and SAR fields across different probe concepts.
• The sleeve probe initially showed a circular SAR pattern (0.81 circularity) but experienced the largest reduction.
• Reflection coefficients varied significantly, with the sleeve probe showing the most sensitivity to tissue dielectric property changes.

Conclusions:

• Different microwave ablation probe designs exhibit unique responses during treatment.
• Changes in tissue dielectric properties significantly influence ablation outcomes.
• Considering probe-specific responses and dielectric property variations is essential during the design phase of microwave ablation probes.