@conference {133, title = {Selective Electroporation of Liver Tumor Nodules by Means of Hypersaline Infusion: A Feasibility Study}, booktitle = {6th European Conference of the International Federation for Medical and Biological Engineering}, series = {IFMBE Proceedings}, volume = {45}, year = {2015}, pages = {821-824}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, abstract = {

Spread tumors in liver are not suitable to be treated with local treatments, such as conventional surgery or radiofrequency ablation, thus entailing a poor prognosis. Electroporation-based therapies imply the delivery of pulsed high electric fields and currently are performed in a local fashion using needle or plate electrodes. Here, however, it is proposed a novel electroporation paradigm in which field delivery is not local. All the tumor nodules will be selectively treated using large plate electrodes at both sides of the liver. By infusing an hypersaline solution of high electrical conductivity through the portal vein, the electrical conductivity of healthy tissues and tumor nodules will be made significantly different so that the electric field will be focused on the undesirable tissues. Numerical simulations were used to evaluate the feasibility of the proposed technique. In addition, an in vivo procedure was carried out to assess whether it is possible and practical to significantly modify the conductivity of the liver tissue by hypersaline infusion. Both the numerical simulations and the in vivo procedure provided encouraging results.

}, keywords = {Disseminated nodules, Electroporation, Hypersaline, Liver, Spread tumors}, isbn = {978-3-319-11127-8}, doi = {10.1007/978-3-319-11128-5_204}, url = {http://dx.doi.org/10.1007/978-3-319-11128-5_204}, author = {Q. Castellv{\'\i} and Patricia S{\'a}nchez-Vel{\'a}zquez and Berjano, Enrique and Burd{\'\i}o, Fernando and Antoni Ivorra} } @article {Trujillo2013, title = {{Can electroporation previous to radiofrequency hepatic ablation enlarge thermal lesion size? A feasibility study based on theoretical modelling and in vivo experiments.}}, journal = {International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group}, volume = {29}, number = {3}, year = {2013}, pages = {211{\textendash}8. {\textcopyright} 2013 Informa UK Ltd.}, abstract = {

PURPOSE: The aim of this study was to assess the feasibility of a hybrid ablative technique based on applying electroporation (EP) pulses just before conducting radiofrequency ablation (RFA). The rationale was that the EP-induced reduction in blood perfusion could be sufficient to reduce the thermal sink effect and hence to increase the coagulation volume in comparison to that created exclusively by RFA. MATERIALS AND METHODS: A modelling study and in vivo experimental study were used. A Cool-tip RF applicator was used both for EP and RFA. RESULTS: Overall, the results did not show any synergy effect from using the hybrid technique. Applying EP pulses prior to RFA did not increase the coagulation zone obtained and the lesions were almost identical. Additional computer simulations provided an explanation for this; the effect of reducing blood perfusion by thermal damage during RFA completely masks the effect of reducing blood perfusion by EP. This is because both thermal damage and EP affect the same zone, i.e. the tissue around the electrode. CONCLUSIONS: Our computer modelling and in vivo experimental findings suggest that the combination of EP and RFA with monopolar applicators does not provide an additional benefit over the use of RFA alone.

}, keywords = {Animals, Catheter Ablation, Combined Modality Therapy, Computer Simulation, Electroporation, Feasibility Studies, Female, Liver, Liver: surgery, Models, Swine, Theoretical}, issn = {1464-5157}, doi = {10.3109/02656736.2013.777854}, url = {http://www.ncbi.nlm.nih.gov/pubmed/23573935}, author = {Trujillo, Macarena and Q. Castellv{\'\i} and Burd{\'\i}o, Fernando and Patricia S{\'a}nchez-Vel{\'a}zquez and Antoni Ivorra and Andaluz, Anna and Berjano, Enrique} } @article {Laufer2010, title = {{Electrical impedance characterization of normal and cancerous human hepatic tissue.}}, journal = {Physiological measurement}, volume = {31}, number = {7}, year = {2010}, pages = {995{\textendash}1009. {\textcopyright} 2010 Institute of Physics and IOP Publishing Limited.}, abstract = {

The four-electrode method was used to measure the ex vivo complex electrical impedance of tissues from 14 hepatic tumors and the surrounding normal liver from six patients. Measurements were done in the frequency range 1-400 kHz. It was found that the conductivity of the tumor tissue was much higher than that of the normal liver tissue in this frequency range (from 0.14 +/- 0.06 S m(-1) versus 0.03 +/- 0.01 S m(-1) at 1 kHz to 0.25 +/- 0.06 S m(-1) versus 0.15 +/- 0.03 S m(-1) at 400 kHz). The Cole-Cole models were estimated from the experimental data and the four parameters (rho(0), rho(infinity), alpha, f(c)) were obtained using a least-squares fit algorithm. The Cole-Cole parameters for the cancerous and normal liver are 9 +/- 4 Omega m(-1), 2.2 +/- 0.7 Omega m(-1), 0.5 +/- 0.2, 140 +/- 103 kHz and 50 +/- 28 Omega m(-1), 3.2 +/- 0.6 Omega m(-1), 0.64 +/- 0.04, 10 +/- 7 kHz, respectively. These data can contribute to developing bioelectric applications for tissue diagnostics and in tissue treatment planning with electrical fields such as radiofrequency tissue ablation, electrochemotherapy and gene therapy with reversible electroporation, nanoscale pulsing and irreversible electroporation.

}, keywords = {80 and over, Adult, Aged, Electric Impedance, Electrodes, Female, Humans, Liver, Liver Cirrhosis, Liver Cirrhosis: pathology, Liver Neoplasms, Liver Neoplasms: pathology, Liver: pathology, Male, Middle Aged}, issn = {1361-6579}, doi = {10.1088/0967-3334/31/7/009}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20577035}, author = {Laufer, Shlomi and Antoni Ivorra and Reuter, Victor E and Boris Rubinsky and Solomon, Stephen B} }