Electroporation to interrupt blood flow

Abstract

A method for disrupting blood flow to undesirable tissue such as cells of a cancerous or non-cancerous tumor is disclosed. It involves the placement of electrodes into or near the vicinity of vessels supplying blood to the undesirable tissue and through the application of electrical pulses causing blood flow disruption. The electric pulses irreversibly permeate the cell membranes, thereby invoking cell death. The irreversibly permeabilized cells are left in situ and are removed by the body immune system. The process may further comprise monitoring blood flow and / or infusion of a material such as a chemotherapeutic agent or marker into the blood.

Description

CROSS-REFERENCE [0001] This application claims the benefit of U.S. Provisional Application No. 60 / 532,588, filed Dec. 24, 2003, which application is incorporated herein by reference.FIELD OF THE INVENTION [0002] This invention relates to the field of electrode devices useful to disrupt blood flow in order to carry out treatments. BACKGROUND OF THE INVENTION [0003] In many medical procedures, such as the treatment of benign or malignant tumors, it is important to be able to ablate the undesirable tissue in a controlled and focused way without affecting the surrounding desirable tissue. Over the years, a large number of minimally invasive methods have been developed to selectively destroy specific areas of undesirable tissues as an alternative to resection surgery. There are a variety of techniques with specific advantages and disadvantages, which are indicated and contraindicated for various applications. For example, cryosurgery is a low temperature minimally invasive technique in w...

AI Technical Summary

Benefits of technology

[0023] In contrast, irreversible electroporation to disrupt blood flow can provide useful treatments. The method is carried out using electrical pulses to serve as the active means for tissue destruction by a specific means, i.e. by fatally disrupting the cell membrane. Electrochemotherapy may be selective, but it does require the combination of chemical agents with the electrical field. Irreversible electroporation to disrupt blood flow, although non-selective, may be used to stop bleeding or for the ablation of undesirable tissue (such as a tumor) as a minimally invasive surgical procedure with or without the use of adjuvant drugs. Its non-selective mode of tissue ablation is acceptable in the field of minimally invasive surgery and provides results which in some ways are comparable to cryosurgery, non-selective chemical ablation and high temperature thermal ablation.

[0026] The invention provides the simultaneous irreversible electroporation of multitudes of cells providing a direct indication of the actual occurrence of electroporation and an indication of the degree of electroporation averaged over the multitude sufficient to disrupt blood flow. The discovery is likewise useful in the irreversible electroporation of cells which make-up vessels and of cells in blood. The benefits of this process include a high level of control over the beginning point of irreversible electroporation and the control of blood flow to and out of very specific areas.

[0027] A feature of the invention is that the magnitude of electrical current during electroporation of the tissue becomes dependent on the degree of electroporation so that current and pulse length are adjusted within a range predetermined to obtain irreversible electroporation of targeted cells of the blood and blood vessels while minimizing cellular damage to surrounding cells and tissue.

[0028] An aspect of the invention is that pulse length and current are precisely adjusted within ranges to provide more than mere intracellular electro-manipulation which results in cell death and less than that which would cause thermal damages to the surrounding tissues.

Problems solved by technology

Others have generally considered irreversible electroporation of tissue to be undesirable due to the possibility of instantaneous necrosis of the entire tissue affected by the electrical field, regardless of its diseased or healthy state.

Images