Simulation Study of Microwave Ablation Carbonization Regulation Based on Electrical Impedance Detection

Microwave ablation still has the problem of high-temperature carbonization in the central region in clinical application, which directly affects the therapeutic effect. Based on this, this paper proposes an electrical impedance detection and evaluation method, which can detect and regulate the regional tissue state in the ablation process in real-time. To investigate the feasibility of the method, firstly, the mathematical and physical models are investigated, and secondly, the effects of different electrode frequencies, numbers, and positions on the impedance measurements are explored; finally, the current field responses under different ablation state mappings are analyzed. The simulation results show information such as the difference in the strength of the surrounding current field due to the difference in conductivity and dielectric constant, and the optimal electrode parameters are mined according to the distribution law such as the sensitivity, and the effective detection range is determined to be the elliptical area of 46x23.2 mm overlapping with the ablation area. As a result, the impedance can reflect the tissue state in this region, thus avoiding tissue carbonization in the central region. It also lays the foundation for ablation range prediction and other electromagnetic diagnostic techniques.