Saturated saline enhances the effect of electrochemical therapy

Analytical and numerical solutions of the potential and electric field generated by different electrode arrays in a tumor tissue under electrotherapy

BACKGROUND

Electrotherapy is a relatively well established and efficient method of tumor treatment. In this paper we focus on analytical and numerical calculations of the potential and electric field distributions inside a tumor tissue in a two-dimensional model (2D-model) generated by means of electrode arrays with shapes of different conic sections (ellipse, parabola and hyperbola).

METHODS

Analytical calculations of the potential and electric field distributions based on 2D-models for different electrode arrays are performed by solving the Laplace equation, meanwhile the numerical solution is solved by means of finite element method in two dimensions.

RESULTS

Both analytical and numerical solutions reveal significant differences between the electric field distributions generated by electrode arrays with shapes of circle and different conic sections (elliptic, parabolic and hyperbolic). Electrode arrays with circular, elliptical and hyperbolic shapes have the advantage of concentrating the electric field lines in the tumor.

CONCLUSION

The mathematical approach presented in this study provides a useful tool for the design of electrode arrays with different shapes of conic sections by means of the use of the unifying principle. At the same time, we verify the good correspondence between the analytical and numerical solutions for the potential and electric field distributions generated by the electrode array with different conic sections.

Experimental application of electrolysis in the treatment of liver and pancreatic tumours: principles, preclinical and clinical observations and future perspectives

BACKGROUND

Electrolytic ablation (EA) is a treatment that destroys tissues through electrochemical changes in the local microenvironment. This review examined studies using EA for the treatment of liver and pancreatic tumours, in order to define the characteristics that could endow the technique with specific advantages compared with other ablative modalities.

METHODS

Literature search of all studies focusing on liver and pancreas EA.

RESULTS

A specific advantage of EA is its safety even when conducted close to major vessels, while a disadvantage is the longer ablation times compared to more frequently employed techniques. Bimodal electric tissue ablation modality combines radiofrequency with EA and produced significant larger ablation zones compared to EA or radiofrequency alone, reducing the time required for ablation. Pancreatic EA has been investigated in experimental studies that confirmed similar advantages to those found with liver ablation, but has never been evaluated on patients. Furthermore, few clinical studies examined the results of liver EA in the short-term but there is no appropriate follow-up to confirm any survival advantage.

CONCLUSIONS

EA is a safe technique with the potential to treat lesions close to major vessels. Specific clinical studies are required to confirm the technique's safety and eventually demonstrate a survival advantage.

The use of a “Liquid” electrode in hepatic electrolysis

BACKGROUND

The use of direct current electrolysis as a local nonthermal ablative technique for colorectal liver metastases promises to be a simple, safe, and effective therapy. Under general anesthesia, electrolysis is presently limited to tumors smaller than 5 cm, due to the protracted nature of its administration. In an attempt to enhance the effect of electrolysis, a direct current was passed through a preinjected bolus of acetic acid.

METHODS

The effect of a combination of electrolysis and an injection of acetic acid was tested in the liver of eight normal pigs. The volumes of necrosis caused were analyzed.

RESULTS

Acetic acid independently produced a volume of necrosis but did not provide a volumetric or rate advantage when used in combination with a direct current. Statistically, the only main effect on the volume of necrosis was a result of electrolysis.

CONCLUSION

The use of 50% acetic acid to augment the efficacy of direct current electrolysis cannot be recommended.