DE10294019B4 - Neurostimulator and data transmission method - Google Patents

Abstract

Neurostimulator (1) comprising: an application device (2) comprising at least one application electrode (3), the application device being a brush electrode consisting of a cannula (40) and wires (41), the cannula (40) at least partially implantable in the body of a patient and having an end (46) to be implanted and an end (47) leading out of the body, the wires being slid over the end of the cannula to be implanted into the nerve tissue to be stimulated and the tissue end the wires forming application electrodes, with the wires in the cannula insulated against each other so that the electronic circuit can supply a different electrical signal to each wire, an electronic circuit (4), characterized in that the cannula (40) consists of an electrically conductive material and connected to the electronic circuit (4) and as an additional Applicable electrode is usable.

Description

This invention relates to neurostimulators according to the preambles of claims 1, 6, 7, 9 and 16. Further, this invention relates to a data transmission method according to the preambles of claims 17 and 19.

A neurostimulator according to the preamble of claim 1 is known from EP 1 048 319 A2 known. A neurostimulator according to the preamble of claim 6 is known from US 5,824,027 known. A neurostimulator according to the preamble of claims 7 and 9 is known from DE 197 58 110 A1 known.

Data transmission methods according to the preambles of claims 17 and 19 are known from the patent US 5,683,422 known. This document describes a method and apparatus for treating neurodegenerative diseases by electrical stimulation of the brain.

Scientists are investigating the phenomenon of excitotoxicity, which refers to the poisoning of nerves due to the excessive excitement of nerve cells. Research has focused on the nerve cells that have glutamate neurotransmitter receptors and are particularly susceptible to persistent arousal (Rothman, S.M., Olney, J.W. (1987) Trends Neurosci., 10, 299-302). When nerve cells are overly active-hyperactive-because they are exposed to many action potentials, they are thought to release excess glutamate or other excitatory amino acids (EAA) at their synapses. This leads to the poisoning of nerve cells that follow hyperactive nerve cells.

Benabid et al. (The Lancet, Vol. 337: 16 Feb. 1991, pp 403-406) have shown that the stimulation of the vim nucleus of the thalamus tremor (tremor of the patient, see Roche Lexicon Medicine, 4th edition, published by the Hoffmann La Roche AG and Urban & Fischer, Urban & Fischer, Munich, 1998). In this case, stimulation frequencies of 100 to 185 pulses per second led to the same physiological response as a violation of this brain area.

Parkinson's disease is the result of degeneration of the substantia nigra pars compactia. It has been shown that subthalamic nerve cells use glutamate as a neurotransmitter to transfer information to their target cells in the basal ganglia. Hyperexcitation, which occurs in Parkinson's disease, releases excess glutamate, which theoretically leads to further degeneration.

The US 5,683,422 suggests stimulating a brain region with a lead implanted into the head. Preferably, a rod with four annular, successively arranged, mutually insulated electrodes is used to stimulate certain brain regions with electrical pulses. In addition, a "housing connection" is provided on the conductive shaft of the rod, so that a total of five application electrodes are available. At least two of these electrodes are driven by a possibly implemented pulse generator.

Further, a sensor may be provided with two electrodes also implemented in the subthalamus region, the substantia nigra, or other brain region whose electrical activity reflects the activity of the degenerate neurons. The sensor electrodes may also be arranged on the line with the stimulating electrodes. The sensor electrodes are connected via electrical lines to an analog-to-digital converter. Alternatively, the signals provided by an external sensor may be transmitted via a telemetric downlink to the implemented pulse generator.

Alternatively, an electrochemical sensor may be provided which measures the amount of glutamate, another neurotransmitter, or a degradation product thereof in the substantia nigra. Such a sensor could consist of an electrode coated with an ion-selective membrane. An example of this type of sensor is described in "Multichannel semiconductor-based electrodes for in vivo electrochemical and electrophysiological studies in rat CNS" by Craig G. van Home et al. (Neuroscience Letters, 120 (1990), pp. 249-252).

The output of the analog-to-digital converter is connected via a bus to a microprocessor, which evaluates the sensor signals depending on the type of sensor used. If the sensor signal exceeds a physician programmed value, stimulation via the stimulating electrodes is increased.

The stimulation pulse rate is generated via a frequency generator programmable via the bus. The amplitude of the stimulation pulse is programmed via the bus and a digital-to-analog converter. Finally, the microprocessor also programs a pulse width control module over the bus to adjust the pulse width of the stimulation pulses.

During implantation, the physician programs certain key parameters into a memory of the stimulation device by telemetry. These parameters may be required. to be updated. To the Key parameters include information on whether to reduce or increase nerve activity, whether an increase in nerve activity at the sensor site corresponds to an increase in nerve activity at the stimulation target or vice versa, pulse width, amplitude, and pacing pulse rate. The doctor may also set upper and lower limits for the key parameters. To increase the stimulation, the stimulation frequency is first increased to its upper limit. Subsequently, the pulse width is increased to its upper limit. Finally, the pulse amplitude is increased to its upper limit. Now an increase of the stimulation within the given limits is no longer possible and an error message via telemetry is sent to the doctor

Superimposed on this algorithm is an additional algorithm to set the stimulation as low as possible but as high as necessary to achieve an adequate level of nerve activity in the subthalamus nucleus. When the pacing parameters are changed, a timer is started. Unless it is necessary to increase the stimulation before the time set in the timer, it may be possible to reduce the stimulation and still maintain an adequate level of nerve activity. Therefore the stimulation is reduced on a trial basis. If the nerve activity remains sufficiently high, the stimulation can be further gradually reduced.

The following companies are active in the market for neurostimulation: Medtronic Inc. (www.medtronic.co.uk) Cyberonics Inc. (www.cyberonics.com), Cochlear Inc. (www.cochlear.com) with system "Nucleus" and EMPI Inc (www.empi.com).

Various measuring methods for determining parameters of the body of a patient are known in medicine. First, the electroencephalography (EEG) should be mentioned here. Here, bioelectric potential fluctuations in the brain, ie the brain electrical activity, are recorded. The measurement is routinely carried out by surface electrodes, but can also be taken from the scalp, for example in unconscious patients with fine needle electrodes. The recording is done by means of 12, 16 or 20 differential amplifiers ("channels") simultaneously.

Electromyography (EMG) refers to the registration of the bioelectrical activity of the musculature. In this method, the electrical potentials are tapped by the insertion of needle electrodes. The potentials can also be tapped from the body surface, but this leads to smaller signals.

A special form of EMG is the electrocardiogram (ECG), in which the bioelectrical potentials or potential differences arising during the excitation propagation and regression of the heart are recorded. The measurement of the potentials is bipolar or unipolar by electrodes from the body surface or directly from the heart, for example during cardiac surgery.

Electrooculography (EOG) records the resting potential of the eye based on the changes in the bioelectrical potential difference between the anterior and posterior poles of the eye. The eye forms an electric dipole, with the Korea positive and the retina negatively charged. The potential changes are reflected in the voltage change of the environment, which in turn can be derived by means of periocular electrodes (Roche Lexikon Medizin a.a.O.).

Cochlear implants stimulate the inner ear with up to 32 channels to help deaf people overcome their disability.

For wireless transmission of data, among other things, the Bluetooth standard has been set, which can be downloaded from the Bluetooth website http: \\ www.bluetooth.com. The Bluetooth standard operates in the frequency band from 2.400 to 2.4835 GHz in most countries except Spain and France. Bluetooth works in the ISM band (ISM = Industrial Scientific Medicine). In this frequency band, 79 channels are set on the frequencies 2'402 + n MHz (n = 0, 1, 2, ..., 78). The transmission is digital. The modulation type is GSSK (Gaussian Frequency Shift Keying). There are three power classes, which are fixed depending on the maximum transmission power. The maximum output power for class 1, 2 and 3 is 100 mW, 2.5 mW or 1 mW. For devices of performance class 1, a power control is provided which limits the transmission power over 1 mW. The step size for the power control should be between 8 and 2 dB.

To ensure user security and confidentiality, the Bluetooth system provides an application layer and a link layer. Four different parameters are used to maintain security at the link layer: a public address (called BD_ADDR) that is different for each Bluetooth device, two secret keys, and a random number that is different for each new transaction. The public address is 48 bits long. The private key used for the authentication is 128 bits long, the private key used for the encryption has a configurable length of 8-128 bits, and the Random number (RAND) also has a length of 128 bits.

The EP 1 048 319 A2 discloses a neural tissue treatment therapy disposed within a brain volume, spinal cord or peripheral nerve. A patient was implanted with a neurological stimulation system to stimulate the patient's subthalamic nucleus. The system includes an implantable therapy delivery device or a pulse generator for generating a number of independent stimulation pulses that are sent to a portion of the brain parenchyma, such as the subthalamic nucleus, by insulated lead wires coupled to electrodes. Each cable is inserted in a cannula. Alternatively, two or more electrodes may be attached to separate conductors which are inserted into a single cable. A lead cable includes six electrodes at its distal end that define the sides of a cube.

Another lead wire shows how five electrodes are arranged at their distal ends in a planar configuration. The electrodes may be driven by an implantable pulse generator coupled to a telemetry antenna. The system allows the selection of different pulse output options after implantation using telemetry communication. Systems with partially implanted generators and high frequency coupling can also be used.

The DE 100 44 115 A1 relates to a method for brain stimulation. A brain stimulation line includes, for example, a macro-segment having an opening located therein in front and a micro-segment movably disposed in the macro-segment. The micro-segment may be moved between a retracted position in which the micro-segment is enclosed within the macro-segment and an extended position in which the micro-segment extends through the opening of the macro-segment. The macro segment has a z. B. made of polyurethane pipe housing in a cannula. The macro-electrode is preferably positioned at the far end of the housing, adjacent to the opening. The macro-electrode may take the form of a conventional DBS (Deep Brain Stimulation) electrode. The size of the surface is in the range of 1 to 20 square millimeters. The microelectrode has an electrode surface at its active tip for single cell cell imaging applications of less than 1 square micrometer. The length of the micro-segment is in the extended position is in the range of about 0 mm to about 25 mm and can be extended by a single cell.

The DE 197 58 114 A1 relates to an electrode arrangement for spinal cord stimulation, in particular for stimulating the thick afferent nerve fibers in the dorsal column. An electrode assembly is implanted in the posterior region of the spinal canal between the spinal cord and the posterior vertebral member and oriented substantially parallel to the spinal canal with one side surface of the stripe-shaped electrode assembly facing the spinal cord, while the other side surface of the electrode assembly faces rearwardly toward the posterior vertebral member , The electrode arrangement has a strip-shaped carrier element, which consists of electrically insulating material. On the side facing away from the spinal cord of the support member a total of eight strip-shaped electrodes are fixed, which act as anodes, while the associated cathodes are mounted on the spinal cord side facing the support member. As a result of this distribution of the electrodes on the two sides of the carrier element, the lateral space requirement of the electrode arrangement is substantially reduced compared to only one-sided arrangement of the electrodes, since the electrodes mounted on opposite sides are insulated from one another by the carrier element and thus no lateral distance between the anodes and cathodes is required. The electrode arrangement has four tripolar electrode configurations arranged one above the other, which can be controlled separately and for this purpose each have separate electrical supply lines which are led to a stimulation device by means of a cable leaving the underside of the carrier element. Stimulation of the spinal cord selectively acts on the thick afferent nerve fibers in the dorsal column as the electrical field is laterally restricted by the external anodes. On the other hand, it is possible in this way to vary the electric field distribution in the stimulation in the lateral direction by the outer anodes of the individual tripolar electrode configurations are subjected to different stimulation amplitudes. As a result, the demands on the lateral positioning accuracy during implantation of the electrode arrangement are reduced, since a slight lateral malposition of the electrode arrangement and an asymmetrical formation of connective tissue on the electrode impedance can be compensated by a correspondingly asymmetrical activation of the external anodes.

The US 5,824,027 and the German family member DE 698 21 114 T2 disclose implantable nerve cuffs for stimulating nerves and / or recording electrical activity in nerves. A nerve cuff has a tubular cuff body with an inner surface surrounding a cylindrical opening for receiving a nerve. A closure allows that the cuff body is opened, placed around a nerve and sealed, with the nerve passing through the opening.

The DE 197 58 110 A1 discloses a stimulation device for spinal cord stimulation. The main goal of the stimulation is to activate the thick afferent nerve fibers in the area of the spinal cord known as the "Dorsal Column". On the one hand, the stimulation voltage must exceed a certain threshold in this case, in order to lead to an activation of the thick afferent nerve fibers. On the other hand, the stimulation voltage must not be increased arbitrarily, otherwise other nerve fibers, such as efferent motor fibers are activated, which is perceived by the patient as unpleasant. In a variant, the epidural impedance is measured, which reflects the thickness of the liquid layer between the electrode and spinal cord and the thickness of the connective tissue layer around the electrode. The thickness of the liquid layer depends on the body position of the patient and is subject to relatively rapid fluctuations in everyday life. It is known to set the stimulation amplitude via an external programming device, which in everyday operation, however, only allows the compensation of slow changes, which usually result from connective tissue formation around the electrode, whereas caused by a change in body position rapid changes in the threshold on this Way can not be considered.

According to the DE 197 58 110 A1 is from the U.S. Patents 5,031,618 and 5,342,409 to solve this problem known to provide in a implantable stimulation device for spinal cord stimulation, a position sensor that detects the body position of the patient and adjusts the stimulation amplitude accordingly to compensate for the changes in body position thickness change of the electrode and spinal fluid layer and regardless of the body position to ensure effective stimulation.

It is the object of this invention to provide a neurostimulator and a data transmission method in order to improve the therapeutic success of the neurostimulator and thus to expand its field of application.

This object is achieved by the teaching of the independent claims.

Preferred embodiments of the invention are subject of the dependent claims.

The following section discusses the diseases that can be treated with neurostimulators. Here Parkinson's disease with the symptoms tremor (trembling of the limbs), Rigor (increased skeletal muscle tension) and akinesia (sedentary lifestyle) should be mentioned. It is to be treated by deep, possibly multichannel brain stimulation of the subthalamus. The deep possibly multi-channel stimulation of the subthalamus is also used for the treatment of essential tremors (dominant hereditary tense tremor), dystonia (disturbance of the natural state of tension of the muscles), dyskinesias (disorder or painful malfunction of the motor process) and epilepsy. Pain patients can get through. Stimulation of the spinal system, especially the spinal cord, can be helped. By stimulating the left vagus nerve epilepsy is treated. Furthermore, a functional electrical stimulation, ie the stimulation of efferent pathways or muscle tissue, for example in paraplegia can be performed. By stimulating the vestibular system with bipolar carbon electrodes, which are placed behind the ears, balance disorders can be treated, for example, based on Kleinhirnerkrankungen or disorders of the vestibular system (organ of balance).

An advantage of using a brush electrode is that a high electrode density is achieved for stimulating tissue.

An advantage of a mesh electrode is that the mesh electrode can be very finely structured by modern etching methods and, like the brush electrode, makes it possible to achieve a high electrode density. By placing a mesh electrode on the cortex or the thalamus, the risk of destruction of nerve tissue is less than when inserting rod-shaped electrodes.

The integration of the electronic circuit on the network electrode has the advantage that the connecting wires between the electronic circuit and the individual electrodes can be kept optimally short and so space is saved in the body of the patient, in the body no unnecessary electrosmog is generated and the implantation is simplified.

Since a mesh electrode by the large number of individual electrodes compared to other neurostimulators has a relatively high energy demand, be led out of the body of the patient by the implanted electronic circuit wires, so that serving as an energy source batteries can be easily changed.

The transmission of data across the wires to the power source reduces exposure of the patient to electromagnetic radiation as compared to a wireless interface.

The control of electrical stimulation in response to different sensor signals provides the opportunity to set the stimulation as low as possible, but as high as necessary, to achieve a certain therapeutic success. EMG and EEG signals can be easily tapped from the patient's body by implanted electrodes, needle electrodes, or surface electrodes glued to the skin. The use of a microphone offers the possibility to consider both body noise and ambient noise in the selection and intensity of stimulation signals. For example, the microphone can take into account noises of the blood, ie flow noise and the pulse beat as well as breathing noises of the patient when choosing the stimulation pulses and their intensity. In addition, a microphone can provide additional information about the patient's environment. Finally, the patient can give acoustic commands to the neurostimulator via the microphone.

The capture of electrical signals on the organ of balance and the stimulation of the right nerves or muscles can be used to treat the sense of balance. In another disease, the sense of balance can be improved by stimulating the organ of balance to avoid falls of the patient.

An advantage of the use of the Bluetooth standard is that the transmission power is controlled above 1 mW to the lowest possible values and so the patient is exposed to only a weak electromagnetic radiation despite wireless connection.

The implantation of an antenna as close to the skin as possible allows the use of a low transmission power and thus reduces the effect of electrosmog on the patient.

An advantage of an optical, in particular an infrared interface is that the patient is spared from radio frequencies. An infrared interface can be implanted under the skin (subcutaneously) because the absorption of infrared radiation by tissue is relatively low. If the neurostimulator is able to transmit measured sensor data via a transmitting device to a control device, then these can be evaluated there in an advantageous manner, because a greater computing power is available in the control device.

The use of a portion of the application electrodes as sensor electrodes leads to a more flexible use of the neurostimulator. In this way it can still be determined after the implantation which electrode is used as a stimulation electrode or as a sensor electrode.

An advantage of the possibility of entering a periodic waveform with more than one pulse per period is that this flexible experimentation with multiple pulses is possible. An advantage of storing the various pulses in a linked list of data structures, each of which may include a reference to another data structure, is the flexible programming of the pulses in a period without limitation to a certain number of pulses. Advantageous in that the pulse width and pulse height of the first pulse is interpreted as a standard pulse width or height, is that input, storage in the controller, and transfer of controller to a neurostimulator requires fewer values if further pulses have the same width and / or or the same height as the first impulse. In particular, the less expensive and thus more ergonomic input is advantageous.

An advantage of the use of an aperiodic waveform is that the signals naturally generated by the nerve cells are only approximately periodic and thus an aperiodic waveform is particularly close to the natural conditions.

The advantage of using any pulse shape instead of a simple rectangular pulse is that this natural pulse shapes can be used.

An advantage of using the same data structures for transmission from the control unit to a neurostimulator, as used for storing a pulse period in the control unit, is that these data structures already efficiently store pulse sequences. The fact that the reference in one data packet or data structure to another data packet or data structure indicates the amount of data transferred between the beginning of the reference and the further data packet represents an adaptation of the reference to a data transmission method.

Hereinafter, preferred embodiments of the invention will be explained in more detail with reference to the accompanying drawings. Showing:

1 a neurostimulator according to the invention with various sensor transmission devices and application electrodes,

2 a neurostimulator according to the invention, which is supplied with electrical power via a supply and communication line, wherein data can also be exchanged with the neurostimulator via this line,

3 an inventive control device with a radio and infrared interface,

4 a brush electrode,

5 a stimulation device according to the invention with a mesh electrode,

6 the representation of a pulse sequence in the display of a control unit,

7 various data structures for storing and transmitting periodic and aperiodic pulse sequences,

8th an input dialog for programming a further pulse in a pulse train as well

9 a menu bar with a drop-down menu for selecting a waveform.

1 shows a neurostimulator according to the invention 1 , The housing of the neurostimulator encapsulates an electronic circuit. The housing can be designed to be tissue-compatible on the outside, so that it can be implanted in the human body. In another embodiment, however, the housing is accommodated outside the body, so that the serving as a power supply battery 23 easy to change. For stimulation of nerve tissue are application or stimulation electrodes 3 intended.

As below with reference to 4 is explained, the application electrodes can be implemented as insulated wires, which are stripped at the end and thus produces an electrically conductive contact with the nerve tissue to be stimulated. The leads to the application electrodes 3 are in a preferred embodiment of a cannula 40 mechanically fixed and electrically shielded. That's why the cannula is 40 preferably made of electrically conductive material and can therefore be used as an additional electrode. The application or stimulation device 2 in one embodiment comprises application electrodes 3 as well as cannula 40 ,

In another embodiment, the application electrodes can be designed as mutually insulated rings on a rod similar to a jack, as in the in the US 5,683,422 Itrel II device is the case. In the preferred embodiment, 20 rings are used. In addition, the rings may be divided into sectors isolated from each other. In this way, the area of a single electrode becomes smaller, so that nerve cells can be more accurately stimulated. In a further embodiment, the application electrodes can be designed as network electrodes. This is related to 5 described. It is advantageous in the use of ring electrodes or sector electrodes that, when the rod-shaped support slips or turns, other rings and / or sectors can be addressed so that the slipping or turning is compensated.

In addition, surface electrodes can also be used as application electrodes. In particular, for the therapy of the equilibrium organ behind the ears attached carbon electrodes are used.

In further embodiments, the electrodes may be isolated from the tissue to be excited so that the stimulation is capacitive. In another embodiment, the stimulation of nerve cells may be magnetic.

In electrical, capacitive or magnetic coupling, the stimulation of nerve cells can be done mainly by increasing the pulse frequency, increasing the pulse width or increasing the pulse height. The pulse height is preferably indicated as voltage in volts. However, it can also be specified as current in ampere, charge in coulomb or magnetic field in Tesla.

In yet another embodiment, tissue may be mechanically stimulated by pressure. For this purpose, piezoelectric elements can be used, alternatively, the use of components that use the effect of magnetostriction, possible. In a further embodiment, the stimulation can be done chemically. By micromechanically produced valves neurotransmitters can be released in the nerve tissue, so that synapses are stimulated.

Finally, thermal stimulation is provided in some embodiments of the invention. A thermal stimulation device can be realized by applying metallic strips on a flexible plastic film. The structuring is preferably carried out by photolithographic methods, by which very fine structures can be etched. At certain points, the thickness and / or width of the metal strips is reduced.

As a result, an increase in the electrical resistance occurs locally, as a result of which, when the current flows, the area reduced in width and / or thickness is heated.

Instead of a reduction of the metal layer in its thickness and / or width may also be other, less conductive material can be used. It may be a metal with higher resistivity or even amorphous or polycrystalline silicon whose resistivity can be adjusted by doping.

The metal tracks are isolated either by a lacquer layer or another film, so that an electrical stimulation of the tissue is prevented. As related to 5 below, an electronic circuit integrated on a silicon chip is preferably integrated on the plastic film. The electronic circuit preferably implements a multiplexer, but may also include a central processing device and a memory.

In preferred embodiments of this invention, various wireless interfaces may be provided. This is particularly advantageous when the housing of the neurostimulator 1 implanted in the body of the patient so that it is difficult to access. In one embodiment, an antenna is 10 provided over which the electrical circuit 4 Can send and receive data.

The antenna 10 For example, it can be embodied as a dipole antenna, with the wires forming the dipole being implanted as close as possible under the skin in order to minimize the load on the patient at radio frequency. By implanting just below the skin, the radio frequency is only weakly absorbed by the body, ensuring low power transmission and good reception.

In a further embodiment, the antenna 10 be designed as a ring antenna. The near field of a loop antenna consists mainly of magnetic field. This affects nerves less than an electric near field, because the information transmission in nerve cells is mainly due to electrical potential differences.

In another embodiment, the electronic circuit 4 via LED (LED) 8th Send data as well as via photodiode 9 receive. If only the transmission or the reception of data is required, then only the light-emitting diode or the photodiode can be provided. Human skin as well as human muscle tissue only weakly absorb red and especially infrared light, so that both light-emitting diode and photodiode can be implanted under the skin (subcutaneously). Instead of a light emitting diode 8th also a laser diode can be used. A laser diode has the advantage that it provides a higher light intensity, so that the reception of the light signals is easier.

Furthermore, the data exchange between circuit 4 and the environment is capacitive or acoustic.

Furthermore, one or more sensors may be connected to the neurostimulator. As sensors, one or more sensor electrodes 11 serve. In 1 are exemplary two sensor electrodes 11 shown similar to the application electrodes 3 through a cannula 40 mechanically guided and electrically shielded. With the sensor electrodes electrical signals can be tapped at different body locations. In particular, EEG and EMG signals can be measured. It is also possible to generate EOG and ECG signals via sensor electrodes 11 to eat. Finally, through sensor electrodes 11 electrical signals are tapped by the equilibrium organ and / or the equilibrium organ may preferably be by application electrodes 3 For example, be stimulated by behind the ears arranged carbon electrodes. This allows for therapy if the part of the brain responsible for the organ of balance has been damaged, for example, by a stroke.

Furthermore, a microphone 12 as another sensor to the neurostimulator 1 be connected. For example, sounds from the patient's body can be evaluated by the microphone. These include blood flow noise, such as the noise or pulsation of the blood and breath sounds. In another embodiment, the microphone 12 Record external sounds that provide additional information about the patient's environment. In another embodiment, the patient may issue voice commands to the neurostimulator 1 to transfer. This can be particularly advantageous in the case of functional stimulation, that is to say the stimulation of muscles or nerves which lead directly to muscles, because the patient can verbally explain what he wants to do and the stimulator ensures that the patient's body behaves accordingly ,

In addition, electrochemical sensors can be provided which measure the blood or lymph composition. In particular, in diabetes patients, the blood sugar content can be determined.

Furthermore, initial sensors, ie acceleration sensors (accelerometers) 14 or yaw rate sensors, such as a gyroscope 15 , be provided. Through these sensors, the movement of the patient including the movement of his limbs can be monitored. If the initial sensors detect the movement of the trunk and limbs of the patient with sufficient accuracy, it is possible to read from the signals of the patient Initial sensors to filter out signals across the patient's tremor or a fall of the patient. However, the difficulty arises in distinguishing desired accelerations and rotations, which arise, for example, when the patient is walking, from the tremor or a fall. For this purpose, for example, offers the frequency analysis of the sensor signals. In order to avoid a fall, the functional electrical stimulation of muscles is useful.

The detection of body movements can be done not only by initial sensors, but in addition to or instead of initial sensors by goniometer. A goniometer is a device to measure connected angles. For example, with a goniometer, the angle between the right upper arm and the upper body of the patient can be measured. Frequency filtering and further analysis methods can also be used to determine the tremor or a rudder or support movement from goniometer signals before or after a fall of the patient. Furthermore, with functional stimulation, it can be monitored to what extent the stimulation of a muscle causes movement, and the stimulation is controlled via this feedback.

In another embodiment, the pressure of at least one foot of the patient is measured against the ground. This can be done for example by piezoelectric or piezoresistive shoe inserts. It has been found that it is the signals of such insoles that are particularly suitable for determining a measure of the state of equilibrium of Parkinson's patients. Furthermore, the rigor of Parkinson's patients can be determined by evaluating such signals.

By piezoelectric or -resistive shoe inserts, the pressure distribution is measured depending on the location of one or both soles. In one embodiment, such an insert may consist of four piezosensors, over which a fixed platform is mounted, on which the patient is supported with one foot.

The electrical circuit 4 consists essentially of one or more analog-to-digital converters 7 that digitize the signal (s) provided by one or more sensors to a central processing unit 5 and one or more digital-to-analog converters 6 containing the application electrodes 3 float. The central processing unit 5 includes a processor and a memory unit. It evaluates the available transmission signals, for example, by frequency filtering and determines, for example, a tremor signal. If the tremor signal is too high, the central processing unit varies 5 the stimulation of one or more application electrodes or application devices accordingly. Depending on the brain region in which an application electrode or device has been implanted, the stimulation must be increased or decreased, for example, to reduce the tremor of the patient. It is known, for example, that the neurons of the basal ganglia have an inhibitory effect, so that excitation of the basal ganglia leads to a lower activity of the thalamus and the motor cortex fields. Thus, if an application electrode were implanted in one of the basal ganglia, it is to be expected that the stimulation of this electrode must be increased in order to reduce the tremor.

In a further embodiment of the invention, the central processing unit 5 filter out various tremor signals from the sensor signals. In this way, implanted in different brain regions application electrodes 3 grounded according to the different tremor signals and thus selectively stimulate certain brain regions more or less. This makes a more targeted therapy possible.

In the electronic circuit 4 Furthermore, switches can be provided to read a larger number of sensors with a small number of analog-to-digital converters. If the sensor signal of a sensor changes slowly in comparison with a possible switching frequency, which is usually the case with electrochemical sensors, then several sensors can be read out in the multiplex method. Further, various modes of operation of the central processing unit may be defined, with each mode of operation determining the reading of particular sensors. Each operating mode can be assigned to a state of the patient. For example, a first mode of operation may be set when the patient is awake and a second mode of operation is set when the patient is asleep. In other embodiments, this rough classification can be further refined.

The determination of the patient's condition can be made on the basis of a suitable analysis of the sensor signals. In particular, a microphone can be used to distinguish between the two patient states. Similarly, a switching device between the digital-to-analog converters 6 and the electrical leads to the application electrodes 3 be provided. Since an application electrode is excited in a preferred embodiment with pulses between which - compared to the pulse width - longer time no excitation occurs, in this way a digital-to-analog converter several application electrodes in a time division multiplex method, ie in temporal succession, control. Is there a large number of electrodes, such as a mesh electrode 50 so can by such Switching the electrodes are selected, which have a great therapeutic effect by their particularly intimate coupling to important nerve cells.

In the storage unit of the central processing unit 5 Furthermore, sensor signals and / or trend data of the sensor signals (see 101 16 361.4) can be stored. Trend data are data obtained from the sensor signals whose information content has been reduced by 2 to 5 orders of magnitude compared to the sensor signals themselves. Furthermore, periods of occurrence of symptoms or abnormalities could be stored. For diagnosis, they can be transmitted to a control unit, which will be described below.

Is the neurostimulator 1 with antenna 10 equipped and can via antenna 10 For example, sensor data can also be received wirelessly via antenna 10 transmitted to the neurostimulator. For therapy monitoring, therefore, the existing sensors can be supplemented by other sensors, as in the German patent application with the official file number 101 16 361.4 is described.

The use of the Bluetooth standard for such an application is particularly advantageous because each radio module is assigned a unique number, thereby simplifying the interaction of multiple devices, as described in application no. 101 16 361.4.

As an energy source for the electronic circuit 4 serves battery 23 , Due to their long life, a lithium battery is predestined for this purpose. In another embodiment, however, electrical energy can also be generated due to substances present in the body, so that a battery is not required. Alternatively, a rechargeable battery such as a lithium ion battery may be used. Charging may be via a coil implanted in the body, preferably near the skin. For energy transmission, a ring antenna described above can also be used. Due to the low absorption of the skin in the red and especially in the infrared spectral range, a suitable solar cell can also be implanted for charging the battery.

In principle, all in 1 shown parts are implanted in the body of the patient. Instead of the piezoelectric shoe inserts, smaller piezoelectric or -resistive sensors can be implanted in the soles of the patient's feet. However, it is only necessary that the stimulation devices, in particular the application electrodes, be implanted in the correct parts of the nerve tissue, in particular of the brain. For all other parts, practicality considerations for or against implantation may be made.

Piezo buzzer and LEDs are used to control the operation of the neurostimulator and alert the patient to critical conditions. Will the neurostimulator 1 not implanted in the body of the patient, it may for example consist of a transparent housing in which various LEDs, including a red and piezo buzzer are housed. Furthermore, controls such. B. an on-off switch may be provided.

2 shows an embodiment of a neurostimulator via the supply and communication line 16 is energized. A supply of electrical energy via electrical lines is particularly advantageous when the electronic circuit 4 relatively many application electrodes 3 which leads to high energy consumption The electronic circuit 4 in 2 contains like the electronic circuit 4 in 1 preferably analog-to-digital converter 7 , a central processing unit 5 as well as digital-to-analog converter 6 ,

In this embodiment, the stimulation device and the electronic circuit 4 preferably housed in the body of the patient with the housing. In such an embodiment, the supply line 16 also be used for communication. The power supply takes place in the low-frequency part of the signal on line 16 and the data communication in the higher-frequency.

In the electronic circuit 4 are coil 21 and capacitor 22 provided to the high-frequency AC voltage component of the line 16 sift out the voltage supplied to the electronic circuit 4 to deliver as constant a DC voltage as possible. About capacitor 20 become the bustle 19 coded data on the voltage on line 16 modulated. The driver acts as a sender. With capacitor 18 The AC component containing the data sent to the neurostimulator is filtered out and from the analog-to-digital converter 17 digitized. The analog-to-digital converter acts as a receiver.

The transmission and reception of data can be time-division multiplexed, so that data is either sent or received at one time. On the other hand, the transmitted data are known in the electronic circuit, so that they can be calculated out of the signal received by the analog-to-digital converter. This way is simultaneous sending and Receiving possible. In another embodiment, the data to be transmitted and received may be from the electronic circuit 4 or a remote station to different carrier frequencies modulated and thus distinguished due to the different carrier frequencies. In this embodiment, capacitors 18 and 20 replaced by bandpass filter.

In a further embodiment, the coil 21 be replaced by a resistor, which usually has a smaller design. If the data is binary-coded, so that a zero corresponds to a slightly lower one and one corresponds to a slightly higher voltage, then the analog-to-digital converter 17 also be replaced by a comparator. At the in 2 open drawn end of the line 16 a similar circuit is provided, as in the electronic circuit 4 in 2 is shown schematically. The capacitor 22 However, it is replaced by a battery as an energy source.

In a further embodiment, the supply and communication line 16 include more than two conductors. If the supply and communication line comprises three conductors, it is preferable to use two conductors for power supply and the third conductor for data communication. The transmission and reception of data preferably takes place in a time division multiplex method. In this embodiment, coil 21 as well as capacitors 18 and 20 omitted. The capacitor 22 can either be omitted or - if necessary for filtering by the central processing unit 5 or through the DA converter 6 generated disturbances on the supply voltage is necessary - at least in its capacity and thus its size be reduced.

The supply and communication line 16 may also include four conductors, in this case two conductors for power supply, one conductor for sending data, and one conductor for receiving data through the electronic circuit 4 is used. Other conductors may be provided for transmitting synchronization signals.

In a further preferred embodiment, the electronic circuit 4 instead of a central processing unit 5 and analog-to-digital converters 7 contain only one multiplexer. In this embodiment, the supply and communication line preferably contains three conductors, namely two for power transmission and one for data transmission to the multiplexer. In this embodiment, a large number of 20 to 50 and more electrodes, in the vicinity of the electronic circuit 4 housing is implanted, by a handy, ie thin and flexible cable 16 to be controlled. For data transmission via cable 16 can also be used advantageously a CAN bus (CAN: Controller Area Network). The CAN bus was developed for the automotive industry and is used there. Due to the large numbers of CAN bus controllers are relatively cheap available.

3 shows the preferred embodiment of a control device according to the invention for the neurostimulators of the invention 24 , In the preferred embodiment, the heart of the controller is a computer, preferably a laptop. The laptop is equipped with a suitable interface for data communication with one or more neurostimulators.

This can be, for example, a radio module for the Bluetooth standard, which is provided by antenna 25 is indicated. The interface can also be through communication line 16 be formed. On the laptop runs a suitable software whose essential characteristics are based on 6 to 9 be explained. When using the Bluetooth standard for communication between neurostimulators and controllers, multiple controllers may monitor a neurostimulator, or a controller may also monitor multiple neurostimulators, as described in Application No. 101 16 361.4 in the context of CPAP devices. This application is incorporated by reference for all purposes.

The controller can also be used to monitor the patient in his home. In this case, it is preferably connected via a modem to a hospital or medical supply, so that the control unit can automatically make an emergency call (see 101 16 361.4).

Furthermore, the control unit can also be equipped with software for diagnosis. This diagnostic software can either evaluate only the data that is currently being measured by the stimulator or that includes the data recorded in the stimulator, if available. In the latter case, the diagnostic quality is improved because the doctor can make his diagnosis due to a much larger database. The stimulator can monitor the patient around the clock.

In a further embodiment, the interface between neurostimulator and control device may be an optical interface, in particular an infrared interface. For this reason are schematically light emitting diode 26 and photodiode 27 in 3 shown. Nowadays, most laptops are equipped with infrared interfaces. However, this has to be done by the light emitting diode 26 generated light at least partially on the photodiode 9 to meet. The same applies to light emitting diode 8th and photodiode 27 , Therefore, LED must 8th and photodiode 27 as well as light emitting diode 26 and photodiode 9 be arranged in spatial proximity and aligned. That is why it is advantageous if LED 26 and photodiode 27 are mounted in an external housing and are connected, for example via cables to the laptop. Thus, the external housing with respect to the patient-side LED 8th and the patient-side photodiode 9 be optimally arranged independently of the laptop. The laptop can stand where it can be comfortably operated.

As mentioned above, the data transmission can also be done by capacitive, magnetic or acoustic coupling.

4 describes a brush electrode as an embodiment of an application device 2 , This is a cannula 40 implanted in the body of the patient so that the end to be implanted 46 the cannula is in or near nerve tissue to be stimulated. In most cases, stimulation of certain brain regions is sought. Therefore, for illustration purposes, the skull bone 44 and the scalp 45 located. Through the cannula 40 Insulated wires are pushed into the nerve tissue to be stimulated. The wires 41 are insulated from each other, but have stripped ends which are the application electrodes 44 form.

To achieve a capacitive coupling, the application electrodes can 44 also be covered with a thin insulation. In particular, this insulation should be thinner than the insulation of the wires in the cannula 40 on the one hand, to stimulate a localized area of the nerve tissue and, on the other hand, to keep the crosstalk between the individual wires acceptably low.

Since the application electrodes are insulated from each other, they can individually as electrodes through the electronic circuit 4 a neurostimulator 1 be controlled. The cannula 40 is made in a preferred embodiment of metal, so an electrically conductive material. That's why it can also be done through the electronic circuit 4 controlled and preferably used as a ground electrode. The leading end 47 the cannula 40 can actually lead out of the scalp or lead in the scalp to an implanted neurostimulator, with its electronic circuit 4 the wires 41 are connected. In a further embodiment, the cannula 40 and wires 41 a distance in the scalp are guided to be led out at a mechanically under-stressed area of the scalp and connected to a body-worn neurostimulator.

Furthermore, the wires 41 at any point, preferably near the application electrodes 44 or near the skull bone 44 , with a multiplexer to a supply and communication line 16 be summarized.

The sensor electrodes 11 can also be performed as a brush electrode. Here are the wires 41 instead of digital-to-analog converters 6 with analog-digital converters 7 connected.

Another embodiment of the stimulation device 2 represents the In 5 illustrated network electrode 50 Here are on an electrically non-conductive support 52 , which is preferably made of a tissue-compatible plastic, a large number of electrodes 51 arranged. The carrier 52 Also includes wires for connection between the individual electrodes and an integrated circuit 52 ,

To the connecting wires between the individual electrodes 51 and the integrated circuit 52 To keep as short as possible, the integrated circuit is integrated into the network electrode. This means that the integrated circuit is arranged in the immediate vicinity of the network electrode. For contacting the integrated circuit with the network electrode, the integrated circuit has bonding points. On the carrier 52 the network electrode corresponding bonding points are provided. In a preferred embodiment, the bond points on the integrated circuit and the corresponding bond points on the carrier 52 connected by electrically conductive epoxy resin adhesive. In another embodiment, the corresponding bonding points are soldered.

The net electrode is placed directly on the cortex (the brain) after opening the skull. Alternatively, it may also be placed on the thalamus or parts of the basal ganglia as far as they can be surgically accessed.

The carrier of the mesh electrode is elastic and has approximately the shape of the brain part, which he should contact. Due to the large number of individual electrodes, a network electrode ensures a relatively high power consumption. Therefore, the integrated circuit is preferably connected to a power source external to the body via a supply and communication line as described in connection with FIG 2 was explained. The integrated circuit thus operates as a multiplexer. However, it can also be a central processing unit 5 so that it can also perform logically more complicated operations than multiplexing.

In order to expand the field of application of the neurostimulators according to the invention, it is advantageous to be able to experiment with different pulse sequences. This requires the central processing unit 5 The electrical circuit of the neurostimulator can be appropriately programmed and stored in the memory of the central processing unit 5 the data for a pulse sequence are stored in a suitable manner. The input of the pulse train typically follows via in 3 represented control unit. Preferably, the software of the controller and the neurostimulator uses similar data structures to effectively store a pulse train, that is, in the smallest possible memory area.

To display the programmed pulse sequence is preferably on a monitor or a display of the controller, the shape of the programmed pulses 62 displayed. The time axis runs from left to right. On her preferably a period of periodic signals and the period corresponding frequency is entered. The period is preferably in the range of 5 ms to 200 s, which corresponds to a frequency of 0.01 Hz to 200 Hz. On the Y axis, the pulse height is plotted as either voltage or current. The aim is to produce pulse heights of ± 250 mV in the nerve tissue. In particular, with capacitive coupling can from the electrical circuit 4 be issued voltages far higher and reach to about ± 20V.

One period begins with a pulse when working with a pair of electrodes. Then a large number of further pulses can be programmed, the number of which is limited only by the memory available in the neurostimulator. Although the memory available in the control unit also limits the number of pulses, a memory that is orders of magnitude larger is available in the control unit, so that this is not the limiting factor. For stimulation periodic and non-periodic pulse sequences can be used. For this purpose, preferably in 7 used data structures shown. These can also be advantageously implemented in an object-oriented programming language such as C ++.

Each of the data structures 70 to 78 has a field named "Type". This is a unique identifier of the data structure - without the string "type:" - stored. However, the identifier does not have to be unique on its own. Rather, the uniqueness can arise only if, for example, the place where the data structure is in memory or the place where there is a reference to this data structure is added.

So are the data structure for describing a pulse train 70 with the identifier 0 and the data structure 78 provided with the identifier 3. The data structures 71 to 74 with the designators 0 to 3 are merely for the description of further pulses, that is, with the exception of the first pulse in connection with the data structure 70 intended.

In the preferred embodiment, the data structure 70 a storage location for the frequency or the period, for the pulse height, for the pulse width, for a reference to other data structures and for a reference to the shape of the pulse. The frequency results as a sweep from the pulse duration, so that either one or the other value can be stored. The frequency or pulse duration, pulse height and pulse width need not be stored as SI units. Rather, they can be suitably scaled, that is, multiplied by a factor so that their values comprise only a small memory area, such as 1 or 2 bytes. With regard to the lower limit of the frequency range of 0.01 Hz, the frequency can be stored in units of 0.01 Hz. To save memory, further, a function value such as the logarithm of frequency, pulse duration or pulse height may be stored.

The reference "more?" May have a reference to one of the data structures 71 to 76 contain. It should be noted here that the identifiers 0 to 5 unambiguously specify a data structure at this point, since references to the data structures 70 and 78 are not provided.

The data structures 71 to 74 describe further rectangular pulses within one pulse cycle. Another rectangular pulse is described by its start time, pulse height, and pulse width. All of this information, however, can only be found in the data structure 74 be made. The missing information in the data structures 71 to 73 are taken from the corresponding data structure data 70 supplemented, so that the pulse height and the pulse width in the data structure 70 have the meaning of a standard pulse height and a standard pulse width. The data structures 71 to 76 each have a field labeled "more?" in which another reference to one of the data structures 71 to 76 can be stored. In this way, an arbitrarily long chain of pulses can be generated.

The "more?" Field of the data structure describing the last pulse contains a value that is known not to refer to another data structure. This value will be in some Programming languages referred to as NULL and preferably has the value 0.

The data structures 75 and 76 are intended to describe non-rectangular pulses. Preferably, signals are used which are naturally generated by nerves. Such signals are non-linear, polyphasic, ie containing multiple phases and spikeartig. Both data structures 75 and 76 include the field "start time". There are as in the data structures 71 to 74 the time at which the impulse begins. In the "Duration" field of the data structure 75 The length of the pulse is given in seconds or any other units. The course of the pulse is indicated by pulse code modulation. In this case, the pulse is composed of n partial pulses. The value n is given in the next field "Number of partial pulses". In the next n fields (then n heights for the respective pulse heights of the partial pulses are given.) In another data structure the duration of the pulse may also be indicated in the field "Duration" instead of the duration of the pulse or the reciprocal of the duration of the pulse or the partial pulses ,

The data structure 76 is similar to the data structure 75 built up. However, the reciprocal of the duration of a partial pulse is specified in the field "Sampling frequency". In addition, the number of partial pulses is not specified. Rather, a particular height, preferably the largest or lowest height or height 0 is excluded as the pulse height of the partial pulses. This particular height completes the list of pulse heights.

In another preferred embodiment, the number of sub-pulses is preferably set to 100 or 1000. In this embodiment, the field "number of partial pulses" in data structure is omitted 75 and the field "special height" in data structure 76 ,

In the data structure 70 is finally a field "form?" Provided. It may be a reference to the data structure 75 or 76 contain. If it contains such a reference, then the fields "pulse height" and "pulse width" of the data structure do not match 70 but rather the data structures 75 and 76 the shape of the corresponding pulse. The field "Form?" Contains the value NULL to indicate that it contains no reference to another data structure.

The data structure 78 is intended to determine a random pulse train with few parameters. Here, in the field "average frequency", the average frequency of the pulses or the sweeping rate thereof, namely the average time interval between the beginnings of the pulses is determined. The actual distance between the beginning of the pulses is determined by a random function, which may for example be based on the evaluation of white noise. A strict randomness is usually not required, so that the random function can also be based on mathematical series that produce only seemingly random values. It may be another data structure similar to the data structure 78 be provided, which additionally defines a lower limit and / or an upper limit for the distance between the beginnings of the pulses. If the random function returns an inappropriate value, this value is discarded and instead another value is generated by the random function. The meaning of the fields "pulse height", "pulse width" and "shape?" Corresponds to that of the respective fields in the data structure 70 ,

The input of the data structure 70 can, for example, through input dialog 80 or a similar input dialog. In the input fields to the right of the words "Repeat Frequency", "Pulse Width" and "Pulse Height", you can enter values for the fields "Frequency", "Pulse Height" or "Pulse Width" of the data structure 70 be entered. The buttons with the inscriptions "Import", "OK, more", "OK, End" and "Cancel" can be clicked on. Clicking on "Import" opens a common file dialog with which, for example, a wave file (* .wav) is imported and into one of the data structures 75 or 76 can be read. A reference to the latter data structure is made when closing the input dialog 80 entered in the field "Form?".

Click on the "Cancel" button to open the input dialog 80 closed without changing the values entered in a data structure 70 get saved. If the "OK, End" button is clicked, the input dialog will be closed and the entered parameters in the corresponding fields of a data structure 70 saved. These steps are also carried out by clicking the "OK, more" button. In addition, a new input dialog opens. It is used to enter one of the data structures 70 to 74 and is different from the input dialog 80 preferably in that the word "repetition frequency" is replaced by "start time".

In this input dialog no pulse width or the same pulse width as in the data structure 70 When entering this input dialog, preferably one of the data structures is entered 72 or 73 created. Does not have a pulse height or the identical pulse height as in the data structure 70 is input, so preferably one of the data structures 71 or 72 created. If a pulse form is read in via the "Import" button, then one of the data structures will be read 75 or 76 instead of the data structures 71 or 74 created when closing the dialog.

Through this operation, the operator is not forced to enter the pulses in their chronological order. Therefore, a sorting function is preferably provided in the control unit which sorts the data structures in such a way that a reference in the field "further?" Of a data structure points to a data structure having a later start time. In this way, when evaluating the data structures, the neurostimulator is not forced to search the remaining list for the next pulse after each pulse. Before the sorting step, it is checked whether the start times of the pulses are still within a period. If a longer start time has been specified than the period duration, then the period duration is subtracted from the start time until the start time lies between 0 and the period duration. This can be realized by a module function.

If two pulses overlap, the pulse height of the pulse is output with the later start time. In another embodiment, the pulse heights of the overlapping pulses are added in the overlap area. However, this requires a higher computing power, which in turn leads to a higher power consumption.

A pulse train may be used instead of the data structure 70 also only by a data structure 75 or a data structure 76 be determined. This corresponds to the in the data structure 75 specified duration of the period. The period duration results with data structure 76 from the number of partial pulses divided by the sampling frequency. If you want to work here with a constant number of partial pulses or interpolation points, a number of 1000 is preferred.

If the control unit is to control a plurality of electrodes via a neurostimulator, the data structure becomes 70 supplemented by a field "Start time". The first impulse no longer starts at the beginning of a pulse period, but at the beginning time. In this way, pulse sequences with a different phase position can be defined for a plurality of electrodes. Each pulse train becomes a data structure 70 or 78 created. Preferably, a selection of the periodic data structures in the display of the control device 24 are displayed. In this case, the individual pulse sequences are displayed in height-offset diagrams with a common time axis and / or in different colors. A function is provided to compress and stretch all or selected pulse trains in height and / or on the time axis.

The input dialog 80 can click on a menu item of a drop-down menu 91 The drop-down menu is for selecting a menu item in a menu bar 91 is opened.

The data structures 70 to 78 are also used to transmit the information about the pulses to be generated from the controller to the neurostimulator. When programming the controller, a reference is implemented, preferably by a pointer or by a handle.

In this case, a pointer specifies a fixed address in the main memory, while a handle (German: handle) is an identifier for a movable memory area. In the data transfer from the controller to the neurostimulator, the reference preferably indicates the amount of data indicating between the beginning of the reference and the data packet having the data structure pointed to by the reference. The amount of data is preferably given in bits, bytes or integer multiples thereof.

LIST OF REFERENCE NUMBERS

1

neurostimulator

2

application device

3

application electrodes

4

electronic switch

5

central processing unit

6

Digital to analog converter

7

Analog-to-digial converter

8th

LED (LED)

9

photodiode

10

antenna

11

sensor electrodes

12

microphone

13

piezoresistive shoe inserts

14

accelerometer

15

gyroscope

16

Supply and communication line

17

Analog to digital converter

18

capacitor

19

driver

20

capacitor

21

Kitchen sink

22

capacitor

23

battery

24

Laptop

25

antenna

26

LED (LED)

27

photodiode

40

cannula

41

wires

43

nerve tissue

44

application electrodes

45

scalp

46

end to be implanted

47

leading end

50

mesh electrode

51

electrodes

52

carrier

53

contact points

54

integrated circuit

60

time analysis

61

voltage axis

62

pulse

70-78

data structures

80

input dialog

90

menu bar

91

Drop-down menu

Claims (20)

Neurostimulator ( 1 ) with: an application device ( 2 ), the at least one application electrode ( 3 ), wherein the application device is a brush electrode which consists of a cannula ( 40 ) and wires ( 41 ), whereby the cannula ( 40 ) is at least partially implantable in the body of a patient and an end to be implanted ( 46 ) and an end leading out of the body ( 47 ), wherein the wires can be pushed beyond the end of the cannula to be implanted into the nerve tissue to be stimulated and the tissue-side end of the wires forming application electrodes, the wires in the cannula are insulated from each other, so that the electronic circuit each wire a different electrical Signal, an electronic circuit ( 4 ), characterized in that the cannula ( 40 ) consists of an electrically conductive material and with the electronic circuit ( 4 ) is connected and can be used as an additional application electrode. Neurostimulator according to claim 1, characterized in that the application device ( 2 ) from a mesh electrode ( 50 ), wherein the network electrode is formed flat and a plurality of individual, mutually insulated and thus separated from the electronic circuit ( 4 . 54 ) controllable application electrodes ( 51 ) electrically connected to the electronic circuit. Neurostimulator according to claim 2, characterized in that the electronic circuit ( 4 . 54 ) into the mesh electrode ( 50 ) is integrated. Neurostimulator according to claim 3, characterized in that the electronic circuit via wires ( 16 ) is connectable with an energy source outside the body and can be powered by the energy source with energy. Neurostimulator according to claim 4, characterized in that the electronic circuit comprises a transmitter ( 19 ) and / or recipients ( 17 ) so that they pass over the wires ( 16 ) can also send or receive data on the energy source. Neurostimulator with: an application device ( 2 ), the two application electrodes ( 3 ), and an electronic circuit ( 4 ), the application electrodes ( 3 ) the application device with electrical signals, characterized in that the application electrodes are carbon electrodes, which are determined and adapted to be mounted behind the ears. Neurostimulator with: an application device ( 2 ), the at least one electrode ( 3 ), and an electronic circuit ( 4 ), the electrode ( 3 ) the application device supplies electrical signals, signals of a sensor ( 11 . 12 . 13 . 14 . 15 ) and controls the electrical signals in dependence on the sensor signals, characterized in that the sensor ( 13 ) picks up a signal that is monotonically related to the force transmitted to the ground via the feet of a patient. Neurostimulator according to claim 7, characterized in that the force is generated by piezoelectric or piezoresistive shoe inserts ( 13 ) is measured. Neurostimulator with: an application device ( 2 ), the at least one electrode ( 3 ), and an electronic circuit ( 4 ), the electrode ( 3 ) the application device supplies electrical signals, signals of a sensor ( 11 . 12 . 13 . 14 . 15 ) and controls the electrical signals in dependence on the sensor signals, characterized in that the sensor is a rotation rate sensor ( 15 ). Neurostimulator according to claim 9, characterized in that the sensor is a gyroscope ( 15 ). Neurostimulator according to one of the preceding claims, characterized in that the electrical circuit is connected via a radio link ( 10 . 25 ) Receives control commands, the radio connection operating in accordance with the Bluetooth standard. Neurostimulator according to claim 11, characterized in that the antenna for the radio connection as close to the body surface, but under the skin, is implanted. Neurostimulator according to one of the preceding claims, characterized in that the electronic circuit via an optical Interface ( 9 . 26 ), preferably an infrared interface, receives control commands. Neurostimulator according to one of Claims 7 to 10 and 11 to 13, insofar as they relate to Claims 7 to 10, characterized in that the neurostimulator has a transmitting device for transmitting measured sensor data via radio ( 10 . 25 ) or light ( 8th . 27 ), preferably infrared. Neurostimulator according to one of claims 1 to 6 and claim 14, characterized in that the electrical circuit has an operating mode in which a part of the application electrodes ( 3 ) is used as sensor electrodes. Neurostimulator, characterized in that it generates a stimulus by mechanical coupling, magnetic coupling, chemical coupling or thermal coupling of a stimulation signal. Data transmission method from a control unit ( 24 ) to a neurostimulator ( 1 ) comprising the steps of: transmitting the period or a corresponding frequency, transmitting data defining a standard pulse shape, such as the width or height of the pulses, characterized by the step of: transmitting a reference to a data packet containing information about the beginning of another one Pulse contains, or transmitting the information that no further data packet follows. A method according to claim 17, characterized in that the reference to another data packet indicates the amount of data transmitted between the beginning of the reference and the further data packet. Data transfer method from a controller to a neurostimulator, comprising the step of: transmitting data ( 78 ), which define an aperiodic pulse shape. A method according to claim 19, characterized in that an average pulse frequency is transmitted.

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