Wound healing patch with guard electrodes
In one example, the present invention is directed to a wound-healing patch including a flexible substrate, at least one wound electrode, at least one guard electrode and at least one return electrode. The guard electrode is positioned between the wound and return electrodes in the electrical path of current traveling between the return and wound electrodes on the surface of the skin, sinking the surface current and force the wound current to travel deeper into the tissue. In the invention, the wound electrode(s) is positioned on a portion of the flexible substrate designed to be placed over wounded tissue and the return electrode is positioned on a portion of the substrate substantially surrounding the wound and guard electrodes and is designed to be placed over healthy tissue.
1. A wound-healing patch comprising:
a flexible substrate;
at least one wound electrode positioned on a portion of said flexible substrate adapted to be placed over a wounded tissue;
at least one return electrode positioned on said substrate remote from said wound-healing electrode, wherein said return electrode is positioned on a portion of said substrate adapted to be place over healthy tissue; and
at least one guard electrode positioned between said at least one of said wound electrodes and at least one of said return electrodes.
2. A wound-healing patch according to claim 1 further comprising a voltage source connected between at least one of said wound electrodes and at least one of said return electrodes, said voltage source being further connected between said return electrode and said guard electrode.
3. A wound-healing patch according to claim 1 further comprising a current source connected between at least one of said at least one wound electrode and at least one of said at least one return electrodes.
4. A wound-healing patch according to claim 1 further comprising at least one resistor connected to at least one of said at least one wound electrode and said guard electrode.
5. A wound-healing patch according to claim 1 further comprising control electronics adapted to control the flow of current through said at least one wound electrode, guard electrode and return electrode.
6. A wound-healing patch according to claim 1 wherein one of said at least one wound-healing electrode, said guard electrode or said at least one return electrode is electrically isolated from tissue when said patch is attached to said tissue.
7. A wound-healing patch according to claim 1 wherein said at least one wound-healing electrode, said at least one guard electrode and said at least on return electrode are electrically isolated from tissue when said wound-healing patch is attached to said tissue.
8. A wound-healing patch according to claim 7 wherein at least one said wound electrode, said at least one guard electrode or said at least one return electrode are isolated from said tissue by a distributed resistive element.
9. A wound-healing patch according to claim 1 wherein said at least one electrode form a ring substantially surrounding said guard electrodes and said wound healing electrodes.