Development of an intraoperative monitoring system for microwave ablations

Microwave ablation therapy is frequently used totreat liver malignancies. To ensure proper tumor treatment, intraoperative feedback regarding ablation performance and lesion size is required. By employing an electrode array aroundthe ablation needle, changes in electrical impedance of ex vivoliver are measured in real time. Timeseries trends of magnitude and phase are measured for 90 °C and 110 °C ablation temperatures. A finite element model is additionally configured to simulate the underlying biological processes. Gradients in the magnitude and phase trends can indicate the growthof the ablation zone. In combination with a preoperative simulation, impedance-based ablation monitoring can be a possibletool to improve future treatments.