Thermal ablation of liver tumors

Thermal ablation uses radio-frequency current to heat up tissue. The electrode is inserted transcutaneously in a minimally invasive way and can be guided through common imaging modalities. Current flows between the electrode and a dispersive electrode or between two or multiple (bipolar) electrodes. Ionic agitation in the tissue results in frictional heat. In order to have an effective treatment, the temperature needs to be between 70°C and 100°C. Above ~50°C, the tissue is irreversibly damaged and above ~70°C, coagulation occurs which is preferred. Above ~100°C, water vapour develops and is undesirable.  Tumor sizes with high volumetric dimensions (larger than 2-3 cm) are difficult to treat with thermal ablation. Advances are necessary in the numerical modelling of the RFA treatment so that the treatment efficiency can be increased. We focus on the development of efficient stochastic thermo-electrical coupled forward models that need to be mathematically developed. Until now, the treatment device is only controlled through this single temperature measurement. More intelligent and accurate numerical inverse procedures are developed for the on-line assessment of the temperature distribution so that the RFA treatment device can be controlled in a more efficient way so to have complete tumor necrosis.