GB2299942A

GB2299942A - Flexible skin contact electrode

Info

Publication number: GB2299942A
Application number: GB9608297A
Authority: GB
Inventors: Mark Brooke-Reid
Original assignee: Face & Body Perfector Ltd
Current assignee: Face & Body Perfector Ltd
Priority date: 1995-04-21
Filing date: 1996-04-22
Publication date: 1996-10-23
Also published as: GB9608297D0

Abstract

An elongate electrode for establishing electrical contact with a patient's body comprises a flexible layer 1 made of an electrically-conductive (carbon-loaded) closed cell foamed plastics material having an exposed lower face 2 for conformal surface contact with the patient's skin. The layer 1 is backed throughout its upper face 3 by a thinner flexible layer 4 of non-conductive foamed plastics material. A thin copper tape 5 is sandwiched between the layers 1 and 4 in electrical surface contact with the face 3 throughout the length of the layer 1. Snapfastener connection of an external lead is made to the electrode via a stud 6 that projects upwardly through the layer 4 from one end of the strip 5.

Description

Electrodes This invention relates to electrodes.

The invention is especially concerned with electrodes for use in establishing electrical contact with the body.

Such electrodes are used for example in cosmetic treatment of the body in which electrical currents are supplied to flow through the skin of the patient into the underlying muscle and tissue. The currents, which are normally of either milli- or micro-ampere magnitude, are supplied via a pair of electrodes that are retained in contact with the skin either side of the region to be treated. Each electrode commonly takes the form of a metal or other electrically-conductive plate which is placed on the body within a fabric envelope so that electrical contact between the electrode and the skin is established through a wall of the envelope, conduction between the electrode and the skin being obtained by soaking the envelope in saline solution.

There are disadvantages associated with using a plate electrode with its fabric envelope, in particular because rigidity of the plate generally limits the area of the skin over which good electrical contact can be achieved.

Furthermore, it is not readily possible, without providing a range of different sizes of electrode, to adjust the electrode-contact area to what is appropriate or desirable for the specific part of the body to be treated and for the individual patient involved.

Moreover, the fabric envelope tends not to retain the saline solution so that it drips unpleasantly, and although the envelope and the plate-electrode can be readily washed and sterilised for re-use, there is a tendency after several uses for the envelope to become stiff and unpleasant to handle.

It is an object of the present invention to provide a form of electrode that may be used in place of a plateelectrode and its fabric envelope, to avoid, or at least reduce, the disadvantages referred to above.

According to the present invention an electrode for establishing electrical contact with the body of a patient, comprises a flexible layer of foam material for making conforming surface-contact with the patient's skin throughout substantially all of one of the major faces of the layer, the layer being of itself electrically conductive, and electrical-conductor means having surface contact with a substantial area of the other major face of the layer for establishing external electrical connection with the electrically-conductive layer throughout said area.

The flexible layer may be of a foamed plastics material, Such material may be carbon-loaded so as to be electrically conductive, and may be of a closed-cell form.

The means for establishing external electrical connection with the electrically-conductive layer may comprise copper tape or other metal strip that is bonded to said other major face of the electrically-conductive layer.

Where the electrically-conductive layer is elongate, the tape or strip preferably extends substantially the full length of that layer.

The electrically-conductive layer may be backed on said other major face by a layer of electrically nonconductive material, and the means for establishing electrical connection with the electrically-conductive layer may in this case be sandwiched between the two layers where it is in surface contact with said other major face. The backing layer may be of a flexible foamed plastics material and may be thinner than the electrically-conductive layer.

An electrode in accordance with the present invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a sectional side view of the electrode; and Figure 2 is a plan view of the electrode of Figure 1 with a backing layer thereof shown partly broken away.

Referring to Figures 1 and 2, the elongate electrode in this case, involves a flexible layer 1 of a foamed plastics material that is carbon loaded so as to be electrically conductive. The layer 1 is exposed throughout a lower, major face 2 for contacting the skin of a patient directly, and is backed throughout the opposite, upper major face 3 by a flexible layer 4 of a foamed plastics material that is electrically nonconductive.

A thin strip 5 of copper tape is sandwiched between the layers 1 and 4 in direct surface contact with the face 3 of the electrically-conductive layer 1 over a substantial area of the face 3. External electrical connection to one end of the strip 5 is made via a metal stud 6 that projects upwardly through the layer 4; the stud 6 forms one part of a two-part snap-fastener connector for attaching an electrical lead to the electrode. The strip 5 extends the length of the electrode from the stud 6 to ensure that distribution of currents supplied to the electrode and flowing via the stud 6, have a reasonably even distribution throughout the layer 1, along the electrode-length.

The flexibility of the layers 1 and 4 enables the electrode to be held in very good conformity and electrical surface-contact with the patient's skin throughout substantially the whole area of the face 2.

Furthermore, it is readily possible to cut the electrode to the shape and size appropriate or desirable for the specific part of the body to be treated and the individual patient involved.

The contact with the patient's skin using the electrode of the invention is direct, and whereas the electrical connection is normally enhanced using a saline solution, the degree to which the saline solution is relied on for a low-resistance electrode-to-skin connection is significantly less than when using a plate-electrode within a fabric envelope. Also, the foam material of the present electrode retains the saline solution without dripping to the extent experienced with the known forms of plate-electrode envelope, and can be readily washed and sterilised without significant deterioration in flexibility and other characteristics. Moreover, the construction is comparatively simple and inexpensive, making it economically possible to use new electrodes for each treatment rather than re-using them.

The use of the non-conductive foam backing provided by the layer 4 has the advantage that the risk of electrical shock to the operator in handling the electrode, is greatly reduced as compared with the known form of electrode.

The layers 1 and 4, which may have thicknesses of 5 mm and 3 mm respectively, may be of closed-cell foam. In this latter regard, for example, the layers 1 and 4 may be fabricated of the foams that are sold under the Trade Mark EVAZOTE as EV45CN and E50 respectively.

Claims

Claims:

1. An electrode for establishing electrical contact with the body of a patient, comprising a flexible layer of foam material for making conforming surface-contact with the patient's skin throughout substantially all of one of the major faces of the layer, the layer being of itself electrically conductive, and electrical-conductor means having surface contact with a substantial area of the other major face of the layer for establishing external electrical connection with the electricallyconductive layer throughout said area.

2. An electrode according to Claim 1 wherein the layer is of a foamed plastics material.

3. An electrode according to Claim 2 wherein the layer is of a carbon-loaded foamed plastics material.

4. An electrode according to Claim 2 or Claim 3 wherein the layer is of a closed-cell foamed plastics material.

5. An electrode according to any one of Claims 1 to 4 wherein the means for establishing external electrical connection with the electrically-conductive layer comprises a strip of metal that is bonded to said other major face of the electrically-conductive layer.

6. An electrode according to Claim 5 wherein the strip of metal is copper tape.

7. An electrode according to Claim 5 or Claim 6 wherein the electrically-conductive layer is elongate and the metal strip extends substantially the full length of the layer.

8. An electrode according to any one of Claims 1 to 7 wherein the electrically-conductive layer is backed on said other major face by a layer of electrically nonconductive material, and the means for establishing external electrical connection with the electricallyconductive layer is sandwiched between the two layers where it is in surface contact with said other major face.

9. An electrode according to Claim 8 wherein the backing layer is of a flexible foamed plastics material.

10. An electrode according to Claim 8 or Claim 9 wherein the backing layer is thinner than the electricallyconductive layer.

11. An electrode for establishing electrical contact with the body of a patient, substantially as hereinbefore described with reference to the accompanying drawings.