Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
505145 | Computers in Biology and Medicine | 2013 | 9 Pages |
In radiofrequency ablation (RFA), saline infusion is beneficial for enhancing electrical conductivity, which allows more energy dissipation into target tissue, resulting in increased lesion size. Computational simulation has been a popular method to estimate lesion size from RFA treatment, but it has not been used effectively for saline-infused RFA, for lack of methods to address the conductivity properties of saline–tissue mixtures. To fill this gap, we propose a microscopic mixture model to derive the effective temperature-dependent conductivities of a saline–tissue mixture. We modeled a small block of 6% hypertonic saline-infused liver tissue as a 1×1×1 cm cube, which was divided into 64–1000 elements, with each element representing either liver tissue or saline. A 1:1 mixing of saline and liver tissue was assumed to calculate the effective conductivities at 30, 50, 70, and 90 °C. Different mixing conditions (2:1 and 1:2 of saline to liver tissue) were also tested to observe the effect of mixing ratio on the resulting data. Then, the derived conductivities were applied for 3D hypertonic saline-infused RFA simulation. The results matched our previous experimental measurements within 13%. The proposed model is customizable in constructing mixtures of multiple components, and can thus be expanded to include the effects of various anatomical microstructures and materials.