WO2016055154A1

WO2016055154A1 - Device for applying a stimulus for transcutaneous electrical stimulation

Info

Publication number: WO2016055154A1
Application number: PCT/EP2015/001958
Authority: WO
Inventors: Andreas HARTLEB
Original assignee: Cerbomed Gmbh
Priority date: 2014-10-11
Filing date: 2015-10-06
Publication date: 2016-04-14
Also published as: DE102014015079A1; DE102014015079B4

Abstract

The invention relates to a device (1) for applying a stimulus for transcutaneous electrical stimulation to the surface of a portion of the human ear (2), said device having a number of electrodes (3, 4), which are arranged at or in an electrode support (5), wherein the device (1) comprises a control apparatus (6), which controls or regulates the establishment of a potential difference between the electrodes (3, 4), wherein the device (1) comprises signalling means (7), which are able to indicate or specify a signal which is dependent on the prevailing resistance between the electrodes (3, 4) when a potential difference is applied and when the device (1) is attached onto or into the ear (3), wherein the signalling means (7) comprises a sound generator (7') and a loudspeaker element (7''), wherein the signalling means (7) is embodied in such a way that it can convert a signal dependent on the measured resistance into an associated sound signal by means of the sound generator (7'), wherein the sound signal can be output by way of the loudspeaker element (7''). In order to be able to find the best possible contact quality for the stimulation in a simple manner, the invention provides for the sound generator (7') to be embodied in such a way that it generates a sound signal in a manner dependent on a change in the measured resistance within a predetermined time.

Description

Device for applying a transcutaneous electrical stimulation stimulus

The invention relates to an apparatus for applying a transcutaneous electrical stimulation stimulus to the surface of a portion of the human ear having a number of electrodes disposed on or in an electrode carrier, the apparatus comprising a controller which controls the production of a potential difference between the electrodes the device comprising signal means which can indicate or indicate a signal which depends on the resistance between the electrodes when the potential difference is present and in the device placed on or in the ear, the signal means comprising a tone generator and a loudspeaker element, wherein the signal means is adapted to convert a dependent of the measured resistance signal by means of the tone generator into an associated audio signal, wherein the audio signal is outputable via the speaker element. A device of the generic type disclosed in DE 10 2013 021 175 AI. Similar and other solutions are described in US 5 514 175 A and US 2009/0082831 Al.

CONFIRMATION COPY It is generally known to influence the neurophysiological and neuroelectric quality and thus the function of the stimulated nerves by invasive and non-invasive stimulation of the nerves. As a result, various disease states can be treated. There are numerous devices for both invasive and non-invasive stimulation.

The present invention focuses on the method of transcutaneous electrical nerve stimulation. In this method, pulse currents of different current forms, amplitudes, pulse durations and frequencies are applied through the skin to different nerves and change their status parameters in an advantageous manner.

The measurement of the prevailing resistance between the electrodes is limited in the US 2009/0082831 AI, however, to check whether a meaningful transcutaneous stimulation is possible at all and to prevent it in the given case.

Furthermore, a device for transcutaneous stimulation of the vagus nerve from DE 10 2010 054 165 B3 is known. Here is described a device whose electrode head is arranged with two electrodes in the area of the cymbal conchae; Such positioning of the electrodes has proved to be advantageous. The area of the cymba conchae is the area of the concha of the ear, which lies above the crus helicis; it is also called Hemiconcha superior. Below the crus helicis downwards extends the area of the cavum conchae.

It has proven to be difficult in this case to arrange the electrode head with the electrodes in the ear in such a way that optimal contact quality for the transcutaneous stimulation is provided. As optimal is not just one to address such contacting of the electrodes that does not cause too high a resistance between the electrodes; Similarly, a too small resistance (corresponding to a short circuit transversal to the skin) between the electrodes is disadvantageous and thus not optimal.

The present invention is based on the object of providing a device of the type mentioned, with which it is possible for the patient or user of the device in a simple manner to position the stimulation device in the ear in such a way that the best possible contact quality for the stimulation is achieved can. Accordingly, the optimal position of the device for efficient transcutaneous stimulation should be easily found.

The solution to this problem by the invention is characterized in that the tone generator is designed such that it generates a sound signal as a function of a change in the measured resistance within a predetermined time (resistance gradient).

The loudspeaker element can be arranged on the device in such a way that it comes to lie near the auditory canal in the case of a device attached to or in the ear, or even protrudes into it.

The tone generator can be designed to generate a tone signal which generates a tone of defined frequency as a function of the measured resistance gradient.

But it is also possible that the tone generator is designed to generate a sound signal that generates a tone of defined amplitude (volume) as a function of the measured resistance gradient. Finally, it can also be provided that the tone generator is designed to generate a tone signal which generates a defined speech output as a function of the measured resistance gradient.

It can also be provided that the tone generator is designed to generate a tone signal which generates a tone sequence with a predetermined sequence of individual tone signals as a function of the measured resistance gradient; the individual audio signals then have the same frequency and the same volume (but not necessarily).

As a further possibility, the tone generator can accordingly generate a tone signal which generates a sequence of tones with different rapid succession of the individual tone signals as a function of the measured resistance gradient, for example in such a way that the speed with which the tone signals follow one another slows down as the contact quality deteriorates and accelerated as the contact quality improves.

The signaling means are preferably firmly connected to the device.

The speaker element may comprise a speaker diaphragm. But it is also possible that the speaker element is or comprises a piezoelectric crystal. Furthermore, it is possible for the loudspeaker element to be designed to output particularly low-frequency tones or to comprise such an element, ie in this case it is a vibrating or oscillating element, the vibration or oscillation not being (only) acoustically, but also on the vibration sense of the skin (father-Pacini body / Corpusculum lamellosum) is perceptible. The electrode carrier is preferably designed such that it comes to rest with the electrodes in the cymbal conchae when the device is attached to or in the ear. According to the invention, it is therefore generally about the optimization of the stimulation quality, which is to be achieved in that the user or patient of the device feedback (feedback) is given by the device on the contact quality. This is done by means of acoustic signals. Thus, the same information is given to the user as to how he may need to change the position of the electrodes on the skin surface in order to achieve a better result.

Depending on the acoustic signal - this is preferably a tone with a defined volume or pitch - the device thus gives the user an indication of how it is ordered to the contact quality of the electrodes. It can then be moved by the user, for example, by "trial and error" of the electrode head on the skin surface until an improved contact quality has set, which is signaled by the sound and in particular its volume or frequency.

With regard to finding an improved position of the electrodes on the skin surface, the user may, inter alia, take the following measures: the change in position of the electrode pair relative to the skin, in particular in the area of the cymbal conchae, may include a translational movement of the electrode head; this movement can generally be provided in all directions on the skin surface and parallel to it. The Stimulationsort can then also by circular pivoting of the Electrode or the electrode carrier can be changed in one place. It can also be made a pivoting of the electrode formed by the plane of the electrodes relative to the skin level in order to achieve a higher degree of parallelism to the skin surface. It can also be a change - usually in the form of an increase - the contact pressure of the electrodes on the skin are envisaged.

If resistance is too low (corresponding to a short circuit along the skin surface from electrode to electrode), the audible signal may indicate that the skin under the electrode and / or the electrode itself must be cleaned.

If the resistance is too high overall, a degreasing of the skin surface can be recommended or carried out as an accompanying measure. On the other hand, the application of a contact medium in a suitably chosen way in question (it is in this case a sufficient amount of contact medium to choose to achieve a contact improvement), but on the other hand, too much contact medium is to be avoided to a "short circuit" (s. above) between the electrodes across the skin surface, which would undermine the intended therapeutic effect).

It can also be provided that the electrodes are provided with structural means for increasing or equalizing the contact conditions (eg a "shell" for the electrode carrier).

The information by means of the signal means provided according to the invention in this case provides an indicator with regard to the electrical Resistance between the electrodes of the stimulation device (or for its reciprocal, ie for the electrical conductivity).

In this case, it is also possible to provide information about the voltage - which, in turn, amounts to the magnitude of the resistance between the electrodes via Ohm's law - which must be applied between the electrodes in order to generate a defined current (that is to say a test current).

Thus, for example, a test current of 100 .mu.Α can be used as the basis and the signal means the voltage required to achieve said test current. Ohm's law (U = R x I) can then be used to make a statement about the existing resistance or the impedance. If too high a voltage is required (above a predetermined limit), the signal means provide the information "no contact" (ie, too high resistance) - represented, for example, by a tone of certain pitch or of a particular kind (eg periodically interrupted tone). However, the device would output even said sound when the current and thus the resistance are too low, ie if "short circuit" is present.

In the case of a suitable test current, however, the audio signal changes, so that the user of the device knows that now a position of the stimulation device and, in particular, its electrodes is found, which is suitable for transcutaneous stimulation.

As explained above, however, the optimal stimulation range must be delimited not only upwards (in the direction of high voltages) but also downwards, for which purpose the above-mentioned "short circuit" is referenced. If the contact quality is too good, possibly even before contact with the ear (for example, if too much contact gel has been applied, which establishes an electrically conductive connection between the electrodes before insertion into the ear), the user of the device should also be audible References to the optimization, analogous to the high voltage, but then also at too low voltage.

It can therefore be said that the production of favorable conditions for efficient transcutaneous stimulation can be clearly defined on the one hand. For this purpose, a defined voltage can be specified, which must be applied for the achievement of a test current. In this case, the resistance, defined by the required voltage for achieving the desired current, is within the therapeutically effective range up to a permissible limit value.

In the presence of unfavorable conditions for efficient transcutaneous stimulation, two cases must be distinguished. On the one hand, the resistance (corresponding to the required voltage to reach a desired current) may be too high because the contact quality between the skin and the electrode is insufficient.

On the other hand, however, the resistance may be too low; There is then a short circuit across the skin surface from the stimulation to the reference electrode, without the skin and thus the receptive fields of the nerves are flowed through by the current. Accordingly, according to the proposed concept, it may be provided that the current status of the contact quality is signaled by characteristic sounds by means of the loudspeaker element to the user of the device. In this connection, the following should be mentioned: The measured resistance values may vary depending on the specific circumstances and on the individual user, so that it is sometimes difficult to determine values ranges for the resistance or the contact voltage in advance, ie before a concrete application be signaled to the user via loudspeaker element. Accordingly, a development provides that the ranges for the measured values and the resulting characteristic tones are individually determined or at least adapted, ie set. So the system would be able to learn so far or it can adapt itself to concrete circumstances in the sense of self-learning software. In this case, it can therefore be provided that a software is used for the operation of the stimulation device, which is "self-learning" and automatically carries out corresponding adaptation.

Since the output sound changes in real time, the user of the device would be constantly informed if he is on the right track in the search for optimal positioning of the electrodes.

Attention should be drawn to the following: Up to now, there has always been talk of a measured resistance, which according to the invention is converted into a sound signal in order to assess the position or contact quality of the electrodes. Of course, Ohm's law also applies analogously to the fact that said contact quality is determined by means of a current measurement - at a given (test) voltage - and converted into corresponding tones. However, as a result, at least indirectly, the electrical resistance or the electrical conductivity (as inverse of the specific resistance) between the electrodes is again determined. In the drawing, an embodiment of the invention is shown. The single figure shows the view of a pinna (auricle), in which a device for applying a transcutaneous stimulation stimulus is inserted. In the figure, a device 1 for transcutaneous stimulation of a portion of the human ear 2 is sketched. The device 1 has a holding rod 8, which is longitudinally displaceable in a base part, which also comprises a control device 6. At the base part, a support part 9 is arranged. The general positioning of the device 1 in the ear 2 results from the marking of the essential regions of the ear 2, namely the pinna P with the cavum conchae Ca, the cymbal conchae Cy, the tragus T and the crus helicis Cr.

At one end of the support rod 8, an electrode support 5 is arranged, which has two electrodes 2 and 4, between which a potential difference is established for the purpose of transcutaneous stimulation.

In that regard, the device 1 initially corresponds to previously known solutions, reference being particularly and expressly made to DE 10 2010 054 165 B3 of the patentee, where such a device is explained in more detail.

The device 1 is accordingly designed to be attached to the ear 2 of the person using the device in the region of the vagus nerve. This can be done a transcutaneous stimulation of the vagus nerve.

It is essential that the device 1 in the present case comprises signal means 7 which indicate or indicate the electrical resistance prevailing between the electrodes 3 and 4 when the device is attached to or into the ear 2. These signal means 7 comprise a tone generator 7 'and a loudspeaker element 7 "which, depending on the measured resistance, emit a sound signal into the auditory canal of the user of the device Accordingly, the signal means 7 comprises a tone generator 7' and a loudspeaker element 7"; The signal means 7 is designed so that it can convert the measured resistance between the electrodes 3, 4 by means of the tone generator 7 'in a sound signal, which is assigned to the measured resistance. The sound signal is then output via the loudspeaker element 7 "directly into the auditory canal of the ear 2.

When moving the electrode carrier 5 with the electrodes 3 and 4, the measured electrical resistance changes, so that depending on this - in the sense of the above explanations - by means of the tone generator 7 'a tone defined pitch (frequency) is generated. The user hears this sound via the loudspeaker element 7 "and thus experiences immediately whether there are good or at least suitable conditions for carrying out a transcutaneous stimulation If, for example, the pitch is in a conspicuously high (or low) range (eg higher than 1,000 Hz), this can signal to the user that the contact quality is not good and a repositioning of the electrode carrier 5 with the electrodes 3, 4 is required Frequency below 200 Hz), the user knows that the contact quality is now good or good. If the resistance is too high, a contact gel can provide a remedy; if the resistance is too low, it may be necessary to clean / degrease the electrodes or the electrode carrier (contact gel) or the skin surface.

By moving the electrode carrier 5 with the electrodes 3 and 4 over the skin surface of the cymbal conchae Cy, the optimum position for the stimulation can be found by observing the sound output from the speaker element 7 ".

Accordingly, the stimulation device 1, and in particular its electrode carrier 5, is displaced over the surface of the skin until the user hears a characteristic sound via the loudspeaker element 7 "(for example a tone with a frequency below 200 Hz), which signals to him that the contact quality is now good. By moving the electrode carrier 5 over the skin surface, the user can thus easily "seek" the optimum position of the electrode carrier. For this purpose, the tone generator 7 'may advantageously be designed such that it generates a tone signal as a function of a change in the measured resistance within a predetermined time (ie a resistance gradient corresponding to a change in resistance per time).

Accordingly, it is thus provided, for example, that the signal means 7 and in particular the tone generator 7 'monitors the prevailing resistance between the electrodes 3, 4 and determines the difference between two measured resistance values which occur at the beginning and at the end of a predetermined time interval (e.g. 0.5 seconds). From this, the resistance gradient (AR / At) can then be determined and a tone signal generated therefrom In the case of a high resistance gradient, an assigned high-frequency sound can be generated, with a low resistance gradient a low-frequency sound can be generated Alternatively, or possibly also additively, it can be provided that, instead of merely outputting a tone, a speech output takes place in plain text, that is to say, for example, to place the stimulation device optimally in the ear, successfully or unsuccessfully or to improve or worsen the contact quality. As "poor contact quality" or "good contact quality" as soon as the right or at least one useful for the stimulation position of the electrode carrier is found.

REFERENCE LIST;

1 device for transcutaneous stimulation

2 ears

3 electrode

4 electrode

5 electrode carrier

6 control device

7 signal means

7 'tone generator

7 "speaker element

8 handrail

9 support part

Ca Cavum conchae

Cy Cymba conchae

T tragus

Cr crus helicis

P Pinna

Claims

claims;

A device (1) for applying a transcutaneous electrical stimulation stimulus to the surface of a portion of the human ear (2) having a number of electrodes (3, 4) disposed on or in an electrode carrier (5), the device (1) comprises a control device (6) which controls the production of a potential difference between the electrodes (3, 4), the device (1) comprising signal means (7) capable of indicating or indicating a signal coming from the between the electrodes (3, 4) prevailing resistance at applied potential difference and at or to the ear (2) attached device (1) is dependent, wherein the signal means (7) comprises a tone generator (7 ') and a speaker element (7 ") , wherein the signal means (7) is designed so that it can implement a signal dependent on the measured resistance by means of the tone generator (7 ') in an associated sound signal, wherein the sound signal via the loudspeaker echerelement (7 ") can be output, characterized in that the tone generator (7 ') is designed to generate a sound signal as a function of a change in the measured resistance within a predetermined time.

Device according to Claim 1, characterized in that the loudspeaker element (7 ") is arranged on the device (1) in such a way that it lies near the auditory canal when the device (1) is attached to or in the ear (2).

Apparatus according to claim 1 or 2, characterized in that the tone generator (7 ') is adapted to generate a sound signal which generates a tone of defined frequency as a function of the measured resistance gradient.

Apparatus according to claim 1 or 2, characterized in that the tone generator (7 ') is adapted to generate a sound signal which generates a tone of defined amplitude (volume) as a function of the measured resistance gradient.

5. Apparatus according to claim 1 or 2, characterized in that the tone generator (V) is adapted to generate a tone signal which generates a defined speech output as a function of the measured resistance gradient.

Apparatus according to claim 1 or 2, characterized in that the tone generator (7 ') is adapted to generate a tone signal which generates a tone sequence with a predetermined sequence of individual tone signals as a function of the measured resistance gradient.

Device according to one of claims 1 to 6, characterized in that the signal means (7) with the device (1) are firmly connected.

Device according to one of claims 1 to 7, characterized in that the loudspeaker element (7 ") comprises a loudspeaker diaphragm.

9. Device according to one of claims 1 to 7, characterized in that the loudspeaker element (7 ") is or comprises a piezoelectric crystal.

10. Device according to one of claims 1 to 9, characterized in that the electrode carrier (5) is formed so that it with the electrodes (3, 4) at or in the ear (2) attached device (1) in the Cymba conchae (Cy) comes to rest.