Disposable Electrodes For Electrical Stimulation Of Muscles And Nerves Of The Head

Abstract

Disposable electrodes capable of conforming to irregular skin surfaces comprise a flexible, electrically nonconductive planar sheet material having one surface thereof coated with a skin adhesive adapted to be applied directly to the skin of the patient, the nonconductive planar body having a projecting tab to which an electrical connection can be made. A conductive foil sheet is adhered to the adhesive coating of the planar sheet, the foil being contiguous with the tab. A nonconductive planar spacing sheet having a surface area smaller than that of the planar sheet is adhered to the adhesive coated surface of the sheet material to overlap a portion of the foil sheet extending from the tab and leave an exposed area of adhesive around the circumference of the spacing sheet for adhering the electrode to the skin of the patient. The overlapped portion of the spacing sheet and foil creates an opening into the interior of the electrode for injection of a liquid electrolyte after the electrode is applied to the skin. The spacing sheet is preferably a non-conductive fine mesh screen. The electrodes are primarily useful in electrically stimulating the muscle complex that works synergistically to close the human mandible.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to disposable electrodes for electrical stimulation of muscles and nerves and to a disposable electrode assembly for electrically stimulating the facial and mandibular nerves which work synergistically to close the human mandible.

2. Prior Art Relating to the Disclosure

Various means of making electrical contact by means of electrodes placed in contact with the skin of an individual are known. Most frequently electrodes are taped to desired areas of the skin so they will remain in continuous contact. Taping of multiple electrodes has not been entirely satisfactory in many instances because of the lack of continuous electrical contact of the electrically conductive material of the electrode with the skin of the patient. The present invention is primarily useful in conjunction with a method for electrically stimulating the muscle complex that works synergisticaly to close the human mandible. Such a method is useful to dentists in fitting dentures, in correcting occlusal difficulties of patients, in reduction of swelling or discoloration after surgical operations or accidental injury, and in treatment of various nerve and/or muscle disorders associated with the facial muscles. As the device is used clinically it is desirable to have a way of quickly and accurately placing electrodes in the correct positions on the patient's face without causing the patient discomfort or inconvenience and yet have the electrodes conform to the skin of the individual and maintain continuous electrical contact. For simultaneous and even stimulation the multiplicity of muscles enervated by the fifth and seventh cranial nerves, it is necessary that the input electrodes be carefully located directly over the mandibular notch on each side of the face and contiguous to the lower lobe of the ear. When so located the fifth and seventh cranial nerves are stimulated by electrical current flowing through the input electrodes and out to a common dispersal electrode placed, preferably, over the cervical spine. There is considerable variation of compressibility of the skin tissues in the area around the mandibular notch. In some areas, such as the zygomatic arch, bone closely underlies the skin and soft tissue while in other areas, such as the mandibular notch, there is an absence of bony support. In general the thickness and compressibility of tissues of the input area vary considerably, and for that reason, flat metal electrodes do not conform to the variations in contour. Therefore, electrical contact is hard to maintain with metal electrodes adhered to the skin.

SUMMARY OF THE INVENTION

This invention relates to disposable electrodes used in electrical stimulation of muscles and nerves and to an electrode assembly for electrically stimulating the multiplicity of muscles enervated by the fifth and seventh cranial nerves with a pulsing electrical current generated by a pulse generating apparatus. Each of the electrodes comprises an electrically non-conductive planar sheet material, such as a vinyl plastic of 1-3 mils thickness having a skin adhesive coating on one side thereof, the planar sheet material having a projecting tab to which is adhered an electrically conductive foil sheet. The foil sheet also covers a portion of the non-conductive planar sheet material. A spacing sheet, preferably an electrically non-conductive fine mesh screen, having a surface area smaller than the surface area of the non-conductive sheet material is adhered to the adhesive coating of the sheet material to overlap the portion of the foil extending from the tab and leave an exposed area of adhesive around the circumference of the spacing sheet for adhering the electrodes to the skin of the patient. The overlapped portion of the spacing sheet and foil creates an opening into the interior of the electrode after it is placed on the skin for injection of a liquid electrolyte. The electrode assembly for electrical stimulation of the muscle complex includes two input electrodes placed on each side of the face and a dispersal electrode. The planar sheet material of the two input electrodes each has a notch adjacent the projecting tab adapted to fit under the respective earlobes of the patient. The notch is located so that the electrode is correctly placed for electrical stimulation of the fifth and seventh cranial nerves. Conductive means leading from a pulse generating apparatus are electrically connected to each of the electrodes by means of clips attached to the respective tabs.

It is the primary objection of this invention to provide disposable electrodes for electrical stimulation of nerves and muscles through the skin.

It is a further object of this invention to provide a disposable electrode assembly for electrical stimulation of the facial muscles with a pulsing electrical current from a pulse generating apparatus.

It is a further object of this invention to provide a disposable electrode assembly which does not have restraining bands or straps.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating the position of the input electrodes on the sides of the face of a patient and a dispersal electrode on the cervical spine of the patient, each of the electrodes being connected through electrical conductive means to a pulse generating apparatus;

FIG. 2 is a front elevation of the adhesive coated surface of one of the input electrodes of this invention;

FIG. 3 is a cross-sectional view of the disposable electrode of FIG. 2 prior to its separation from a backing sheet;

FIG. 4 is a cross-sectional view of the disposable electrode of FIG. 2 adhered to the skin of the patient;

FIG. 5 is a cross-sectional view of the disposable electrode of FIG. 2 illustrating the electrode adhered to the skin of the patient and an electrolyte being injected into the interior pocket formed by the spacing sheet; and

FIG. 6 is a cross-sectional view of the disposable electrode of FIG. 2 showing electrically conductive means secured to the tab extending from the upper end of the electrode.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The disposable electrode assembly of this invention is primarily useful in electrical stimulation of the muscle complex through the fifth and seventh cranial nerves with resultant involuntary closure of the human mandible. The method of producing a muscularly balanced closure of the human mandible through electrical stimulation of the masticatory and facial muscles is described in detail in copending application Ser. No. 855,480, filed Sept. 5, 1970, now U.S. Pat. No. 3,593,422, and entitled "Method of Producing a Muscularly Balanced Closure of the Human Mandible." The copending application describes a method of involuntarily closing the human mandible for various clinical objectives by electrically stimulating the muscles enervated by the fifth and seventh cranial nerves on both sides of the face. Stimulation results in coordinated contraction of the masticatory and facial muscles controlling opening and closing of the mandible. In practicing the method described for various clinical objectives, it is essential that the input electrodes placed on each side of the face be in continuous electrical contact so that the current flow through the skin is not interrupted at any time. If the current flow through the skin varies, it gives rise to unequal stimulation of the muscles on either side of the face and is unacceptable.

FIG. 1 of the drawings shows a disposable input electrode 10 and common dispersal electrode 20, secured in specified locations to the head of a patient. The input electrodes are adhesively secured to the skin of the patient, one on each side of the face in a position for electrical stimulation of the fifth and seventh nerves through the mandibular notch. This is done most effectively if the electrodes are located over the opening in the bones of the face called the mandibular notch. In order to correctly position the input electrodes on the face of the patient, the input electrodes are formed with a shoulder portion or notch which is positioned directly under the respective earlobe of the patient. The notch locates the correct position of the electrode on the side of the patient's face.

Each of the input electrodes comprises a flexible, planar sheet material of vinyl plastic or other suitable non-conductive material 12 having a tab portion 14 extending outwardly from the circumference of the sheet. Although the input and dispersal electrodes are illustrated as being generally rectangular or square, the particular shape is not of any significance. Preferably, however, the input electrodes are formed with a notch or shoulder portion 16 to correctly locate the position of the input electrodes on each side of the patient's face. The notch should be located under the lobe of the ear such that the central portion of the electrode is directly over the mandibular notch of the patient on each side of the face for electrical stimulation of the fifth and seventh cranial nerves. One side of each of the electrodes is coated with a commercially available and conventional skin adhesive. The entire surface is coated with the adhesive.

A strip of electrically conductive foil 18 is adhered to the adhesive-coated tabular surface 14 of the non-conductive sheet material and extends past the tab toward the central portion of the sheet material. A planar, flexible, spacing sheet 19 is adhered to the adhesive-coated surface of the electrode so that it overlaps the foil extending from the tab 14. The surface area of the spacing sheet 19 is smaller than that of sheet material 12 to leave an exposed area of adhesive around the outer circumference of the sheet 19 for adhering the electrode to the skin of the patient. The spacing sheet should be porous for absorption of a liquid electrolyte. A material which has been found to work satisfactorily and which is economical is a fine mesh screen of glass fiber which is both electrically nonconductive and capable of holding the electrolyte satisfactorily.

For shipping and storage a set of electrodes which includes two input electrodes 10 and a dispersal electrode 20 is adhered to a backing sheet 30 of conventional character. When it is desired to use the electrodes, the facial skin is scrubbed with alcohol or other material around the earlobes and the nape of the neck to remove skin oils and makeup. The electrodes are peeled from the backing sheet 30 by holding the tab portion 14 and peeling it away from the backing sheet. The input electrodes which are marked right and left are applied on each side of the face of the patient with the notch portion 16 directly under the earlobe. The adhesive coated sheet 12 is pressed firmly against the skin to adhere it. The dispersal electrode is applied similarly and is preferably centered at the nape of the neck directly under the hairline. The tab portion of each of the input electrodes is then bent back to reveal an opening or pocket in the interior of the electrode where the spacing sheet is located. An electrolyte, preferably in gel form, is injected, as illustrated in FIG. 5, into the pocket. The electrolyte is held by the porous spacing sheet. The opening is partially filled and, after filling, is gently pressed to spread the gel so that good electrical contact between the skin and the metallic tab extending from the tab portion is insured. Clips connected to electrically conductive wires are attached to the tab portion of each of the electrodes and to the pulse generating apparatus. When the clips are attached, the apparatus is ready for use. After use the electrodes are removed by detaching the clips, stripping them from the skin and disposing of them.

The electrodes described are economically manufactured, easy to use, and have many advantages over those in common use. Although described with particular reference to electrical stimulation of the facial and mandibular muscles, the electrodes may be used in any application where electrical stimulation through the skin is necessary or where electrical pickup through the skin of the patient is needed.

Claims

The embodiments of the invention in which a particular property or privilege is claimed are defined as follows: 1Disposable electrodes for application directly to the skin of a patient comprising:

a flexible, electrically non-conductive, planar, synthetic plastic sheet having a thickness ranging from 1 to 3 mils. coated with a skin adhesive on one side thereof, the plastic sheet having a projecting tab extending from one edge of the sheet for connection to a flexible lead wire and a shoulder portion extending outwardly from an adjacent edge of the planar sheet for fitting under the earlobe of the patient to correctly place the electrode on the face of the patient for electrical stimulation of the fifth and seventh cranial nerves through the mandibular notch region,

an electrically conductive foil sheet adhered to the adhesive-coated projecting tab and extending part way across the central area of the planar sheet, and

a flexible, fine mesh, electrically non-conductive screen material adhered to the adhesive-coated surface thereof having a surface area smaller than the surface area of the non-conductive planar sheet and overlapping the portion of the foil sheet extending across the central area of the planar sheet from the tab and leaving an exposed area of adhesive-coated surface around the remaining edges thereof for adhering the adhesive-coated sheet to the skin of the patient, the overlapped portion of the screen material and foil creating a pocket when the electrode assembly is adhered to the

skin of the patient for injection of a gel electrolyte. 2. A disposable electrode assembly for electrical stimulation of facial muscles with a pulsing electrical current from a pulse generating apparatus comprising:

a pair of input electrodes, each of the input electrodes comprising: (1) a flexible, electrically non-conductive, planar, synthetic plastic sheet having a thickness ranging from 1 to 3 mils. and having an adhesive coating on one side thereof, the sheet having a projecting tab extending from one edge of the sheet for connection to a flexible lead wire and a shoulder portion extending outwardly from an adjacent edge of the sheet for fitting under the earlobe of the patient to correctly place the electrode on the face of the patient for electrical stimulation of the fifth and seventh cranial nerves through the mandibular notch region; (2) an electrically conductive foil sheet adhered to the adhesive coated surface of the projecting tab and extending part way across the central area of the plastic sheet; (3) a flexbile, fine mesh, electrically nonconductive screen material having a surface area smaller than the surface area of the nonconductive plastic sheet and overlapping the portion of the foil sheet extending across the central area of the planar sheet from the tab and leaving an exposed area of the adhesive coated surface around the remaining edges thereof for adhering the adhesive-coated planar sheet to the skin of the patient, the overlapped portion of the screen material and foil creating a pocket when the electrode is adhered to the skin of the patient for injection of a gel electrolyte:

a common dispersal electrode comprising: (1) a flexible, electrically nonconductive, planar plastic sheet having an adhesive coating on one side thereof adapted to be secured to the skin of the patient, the sheet having a projecting tab extending from one edge thereof for connection to a flexible lead wire, (2) an electrically conductive foil sheet adhered to the adhesive coated surface of the projecting tab and extending part way across the central area of the planar sheet, (3) a planar, flexible, fine mesh, electrically non-conductive screen material having a surface area smaller than the surface area of the planar sheet and overlapping the portion of the foil sheet extending across the central area of the planar sheet to leave an exposed area of adhesive around the remaining edges thereof for adhering the electrode to the skin of the patient, the overlapped portion of the screen material and the foil creating a pocket when the electrode is adhered to the skin of the patient for injection of a liquid gel electrolyte therein, and

flexible lead wires connected to the dispersal electrode and the input electrodes for receiving current from a pulse generating apparatus.