Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
  • A61N1/00—Electrotherapy; Circuits therefor
  • A61N1/18—Applying electric currents by contact electrodes
  • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
  • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
  • A61N1/3605—Implantable neurostimulators for stimulating central or peripheral nerve system
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
  • A61N1/00—Electrotherapy; Circuits therefor
  • A61N1/18—Applying electric currents by contact electrodes
  • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
  • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
  • A61N1/3605—Implantable neurostimulators for stimulating central or peripheral nerve system
  • A61N1/3606—Implantable neurostimulators for stimulating central or peripheral nerve system adapted for a particular treatment
  • A61N1/36082—Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease

Definitions

• the invention relates to a device for treating patients by means of brain stimulation according to the preamble of claim 1, an electronic component and the use of the device and the electronic component in medicine.
• nerve cell clusters are located in defined areas of the brain, e.g. B. the thalamus and basal ganglia, pathologically active, for example, exaggerated synchronously.
• a large number of neurons form action potentials synchronously, ie the neurons involved fire excessively synchronously.
• the neurons fire differently in these brain areas, for example in an uncorrelated manner.
• the pathologically synchronous activity changes the neuronal activity in areas of the cerebral cortex, such as, for example, in the primary motor cortex, for example by forcing their rhythm on them, so that the muscles controlled by these areas ultimately have pathological activity, e.g. B. a rhythmic tremor.
• a depth electrode is implanted.
• a cable leads from the head to the so-called generator, which comprises a control unit with a battery and is implanted under the skin, for example in the region of the clavicle.
• the aim of this method is to suppress the firing of the neurons in the target areas.
• This standard deep stimulation acts like a reversible lesion - that is, like a reversible switch-off of the tissue.
• the mechanisms of action, ie how exactly the standard irritation works, has not yet been sufficiently clarified.
• the high-frequency continuous stimulation as an unphysiological, ie unnatural input in the area of the brain, for example the thalamus or the basal ganglia
• stimulation with a higher stimulus amplitude must then take place as a result of this adaptation.
• the greater the amplitude of the stimulus the greater the likelihood that it will result from the Irritation of neighboring areas leads to side effects - such as dysarthria (speech disorders), dysaesthesia (sometimes very painful sensations), cerebellar ataxia (inability to stand without outside help) or schizophrenia-like symptoms etc.
• side effects cannot be tolerated by the patient.
• the treatment therefore loses its effectiveness in these cases after a few years.
• the activity of the affected nerve cell associations should not simply be suppressed, but should be brought closer to the healthy functional state.
• the side effects such as dysarthria, dysaesthesia, cerebellar ataxia or schizophrenia-like symptoms, etc., which result from the methods according to the prior art, are to be eliminated or at least reduced.
• the device according to the invention it is now possible to treat patients without adaptation to the non-physiological permanent stimulus taking place, the above-mentioned side effects being reduced or prevented.
• the battery or power consumption can be drastically reduced, which is why the batteries need to be replaced or recharged less frequently.
• the drawing shows an exemplary embodiment of the device according to the invention.
• Fig. 1 A block diagram of the device
• the device according to the invention shown in FIG. 1 comprises an isolation amplifier (1) to which at least one electrode (2) and sensors (3) for detecting physiological measurement signals are connected.
• the isolation amplifier is also connected to a unit (4) for signal processing and control, which is connected to an optical transmitter for stimulation (5).
• the optical transmitter (5) is connected via optical fibers (6) to an optical receiver (7) which is connected to a simulator unit (8) for signal generation.
• the simulator unit (8) for signal generation is connected to the electrode (2).
• a relay (9) or transistor is located at the input area of the electrode (2) into the isolation amplifier (1).
• the unit (4) is connected via a line (10) to a telemetry transmitter (11) which is connected to a telemetry receiver (12) which is located outside the device to be implanted and to which a means for visualization, processing and Storage of the data (13) is connected.
• a telemetry transmitter (11) which is connected to a telemetry receiver (12) which is located outside the device to be implanted and to which a means for visualization, processing and Storage of the data (13) is connected.
• a telemetry transmitter which is connected to a telemetry receiver (12) which is located outside the device to be implanted and to which a means for visualization, processing and Storage of the data (13) is connected.
• a means for visualization, processing and Storage of the data (13) is connected.
• epicortical electrodes, depth electrodes, brain electrodes or peripheral electrodes can be used as sensors (3).
• the electrode (2) is at least two wires, at the ends of which a potential difference is applied for the purpose of stimulation. It can be macro or microelectrodes. In addition, but not necessarily, a potential difference can be measured via the electrode (2) in order to determine a pathological activity. In a further embodiment, the electrode (2) can also consist of more than two individual wires, which can be used both for determining a measurement signal in the brain and for stimulation. For example, four wires can be accommodated in one conductor cable, it being possible to apply or measure a potential difference between different ends. This allows the size of the derived or stimulated target area to be varied.
• the number of wires from which the electrode is built is limited according to the upper values only by the thickness of the cable to be inserted into the brain, so that as little brain material as possible is to be damaged.
• Commercially available electrodes comprise four wires, but five, six or more wires, but also only three wires can also be included.
• the electrode (2) comprises more than two wires
• at least two of these wires can also function as a sensor (3), so that in this special case there is an embodiment in which the electrode (2) and the sensor (3 ) are combined in a single component.
• the wires of the electrode (2) can have different lengths, so that they can penetrate into different brain depths. If the electrode (2) consists of n wires, then stimulation can take place via at least one pair of wires, any sub-combination of wires being possible during pair formation.
• sensors (3) that are not structurally combined with the electrode (2) can also be present.
• the unit for signal processing and control 4 includes means for univariate and bivariate data processing, as described, for example, in "Detection of n: m Phase Locking from noisysy Data: Application to Magnetocephalography" by P. Tass, et. Al. In Physical Review Letters, 81,3291 (1998).
• the device is equipped with means which recognize the signals of the electrode (2) and or of the sensors (3) as pathological and, in the presence of a pathological pattern, emit stimuli via the electrode (2) which cause the pathological neuronal activity either suppressed briefly or modified so that it comes closer to natural, physiological activity.
• the pathological activity differs from the healthy activity by a characteristic change in its pattern and / or its amplitude.
• the means for recognizing the pathological pattern are a computer which processes the measured signals of the electrode (2) and / or the sensor (3) and compares them with data stored in the computer.
• the computer has a data carrier that stores data that were determined in the course of a calibration procedure.
• this data can be determined by systematically varying the stimulation parameters in a series of test stimuli and the success of the stimulation via the electrode (2) and / or the sensor (3) by means of the Control unit (4) is determined.
• the determination may be by uni-, bi - and multivariate data analysis to identify the frequency characteristics and the interaction (.
• the device therefore comprises a computer which contains a data carrier which bears the data of the clinical picture, compares it with the measurement data and, in the event of pathological activity, emits a stimulus signal to the electrode (2) so that brain tissue is stimulated.
• the data of the clinical picture stored in the data carrier can either be person-specific, optimal stimulation parameters determined by calibration, or a data pattern that has been determined from a patient collective and typically represents optimal stimulation parameters that occur.
• the computer recognizes the pathological pattern and / or the pathological amplitude.
• the types of stimuli used for the treatment of the pathological findings are known to the person skilled in the art.
• longer periodic sequences of individual stimuli or more complex stimulus sequences can be used as described below under 1. and 2.
• these complex stimuli are on the one hand a double pulse, which consists of two qualitatively different pulses, for example a strong and a weak pulse, and on the other hand a high-frequency (more than 100 Hz) or low-frequency (between 5 and 20 Hz) pulse sequence, followed by one single pulse.
• the pathological activity in the case of using longer periodic
• the consequences of individual stimuli are typically briefly suppressed and, in the case of more complex stimulus sequences, typically brought back to natural, non-pathological activity or completely adjusted to it.
• the device according to the invention is designed such that in the event that the electrode (2) and / or the sensor (3) determines that the pathological activity has ceased after the stimulation, the stimulation is interrupted.
• the computer determines whether the pathologically increased amplitude or the pathologically increased pronounced pattern is present. This is done using the data analysis implemented by the electronics. As soon as these pathological features are detected again, the next stimulation begins in the same way.
• the stimulation is switched on and off either by a control unit or by two control units communicating with one another, which are combined in FIG. 1 as control unit (4).
• the control unit (4) can comprise, for example, a chip or another electronic device with comparable computing power.
• the control unit (4) preferably controls the electrode (2) in the following manner.
• the control data are forwarded by the control unit (4) to an optical transmitter for stimulation (5), which controls the optical receiver (7) via the light guide (6).
• the stimulation control is galvanically decoupled from the electrode (2). This means that interference signals from the unit for signal processing and control (4) into the electrode (2) are prevented.
• a photo cell can be used as the optical receiver (7).
• the Optical receiver (7) forwards the signals entered via the optical transmitter for stimulation (5) to stimulator unit (8). Targeted stimuli are then passed on via the electrodes (2) to the target region in the brain via the stimulator unit (8).
• a relay (9) is also triggered, starting from the optical transmitter for stimulation (5), via the optical receiver (7), which prevents the interference of interference signals.
• the relay (9) or the transistor ensures that the neural activity can be measured again immediately after each stimulus without the isolating amplifier overdriving.
• the galvanic decoupling does not necessarily have to be done by optically coupling the control signals; rather, other alternative controls can also be used. These can be acoustic couplings, for example in the ultrasound range. Trouble-free control can also be implemented, for example, with the aid of suitable analog or digital filters.
• the device according to the invention is preferably connected to means for visualizing and processing the signals and for data backup (13) via the telemetry receiver (12).
• the unit (13) can have the above-mentioned methods for uni-, bi- and multivariate data analysis.
• the device according to the invention can be connected to an additional reference database via the telemetry receiver (13), for example in order to accelerate the calibration process.
• an electrode (2) such as a) brain electrode, z. B. a depth electrode, a b) epicortocal electrode or via c) a muscle electrode and serves as a feedback signal, ie control signal, for demand-controlled stimulation B).
• the feedback signal from the sensor (3) is transmitted to the isolation amplifier (1) via a line.
• the feedback signal can also be transmitted telemetrically - without using an isolation amplifier.
• sensor (3) is connected to an amplifier via a cable.
• the amplifier is connected to a telemetry transmitter via a cable.
• sensor (3) and amplifier and telemetry transmitter are implanted, for example, in the area of an affected limb, while the telemetry receiver is connected to the control unit (4) via a cable.
• Electrode (2) which in this case also take on the function of a sensor (3), which is also used for stimulation. If the electrode (2) consists of more than three wires, at least two of these wires can act as sensors (3), in which case there is no stimulation via these wires.
• the pathological neuronal activity can also occur in different neuron populations. For this reason, several signals measured via the electrode (2) and / or sensors (3) can also be used to control the stimulation. Whenever a pathological characteristic of the activity is detected in at least one of the neuron polulations, an irritation is triggered.
• the electrode (2) can also act as a sensor (3). This makes it possible to derive the activity of the neuron population at the treatment point of the electrode (2).
• the measurement signal or the measurement signals serve or serve as feedback signals. This means that stimulation takes place as a function of the activity detected via the measurement signal. Whenever a pathological characteristic of neuronal activity (that is, pathologically increased amplitude or pathologically increased pronounced activity pattern) begins and increases, stimulation takes place.
• the stimulation B) can take place in different ways.
• a synchronized neuron population can be desynchronized by applying an electrical stimulus of the correct intensity and duration, provided the stimulus is administered in a vulnerable phase of pathological rhythmic activity, these optimal stimulation parameters (Intensity, duration and vulnerable phase) are determined as part of the calibration procedure, for example by systematically varying these parameters and comparing them with the success of the stimulation (e.g. damping the amplitude of the bandpass-filtered feedback signal).
• the calibration can be accelerated by using so-called phase resetting curves.
• Single pulse stimulation is only efficient if the stimulus is applied at or close enough to the vulnerable phase of the activity to be stimulated. Alternatively, complex forms of stimulation can be used.
• control unit (4) must predict the occurrence of the vulnerable phase in advance if the threshold value determined by the calibration is exceeded by means of standard prediction algorithms implemented by the electronics (control unit (4)) in order to hit it precisely enough Using complex stimuli, the control unit (4) only has to cause a new complex stimulus of the same type when the threshold value determined by the calibration is exceeded.
• Simple stimuli are, for example, a) single pulse stimulations.
• Complex stimuli are, for example, b) double pulse stimulation, c) stimulation with a resetting high-frequency pulse train (> 100 Hz pulse train), followed by a desynchronizing single pulse, d) stimulation with a resetting low-frequency pulse train - in the range of the pathological frequency, e.g. Parkinson's disease approx. 5 Hz -, followed by a desynchronizing single pulse.
• a resetting high-frequency pulse train > 100 Hz pulse train
• d stimulation with a resetting low-frequency pulse train - in the range of the pathological frequency, e.g. Parkinson's disease approx. 5 Hz -, followed by a desynchronizing single pulse.
• the device is equipped with means for wireless transmission of data, such as the measurement signals and stimulation control signals, so that data can be transmitted from the patient to an external receiver, for example for the purpose of therapy monitoring and optimization. In this way it can be recognized at an early stage whether the stimulation parameters used are no longer optimal.
• data can be transferred wirelessly to a reference database and early reactions to typical changes in irritability in the target tissue can be made
• an electronic component is made available which recognizes and eliminates the occurrence and elimination of a pathological feature of the electrical signal, which is measured by the sensor (3, 2) emits at least one pulse on the electrode (2) when the pathological feature occurs and switches off the pulse when the pathological feature disappears.
• the sensor (3, 2) emits at least one pulse on the electrode (2) when the pathological feature occurs and switches off the pulse when the pathological feature disappears.
• it comprises univariate data processing and furthermore multivariate and / or bivariate data processing.
• the electronic component is preferably designed such that at least one of the univariate, bivariate and multivariate data processing works with methods of statistical physics, the method of statistical physics being able to come from the area of the stochastic phase setting.
• the device according to the invention and the electronic component according to the invention can be used in medicine, preferably in neurology and psychiatry.

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• Health & Medical Sciences (AREA)
• Neurology (AREA)
• Neurosurgery (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Radiology & Medical Imaging (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Electrotherapy Devices (AREA)
• Measuring And Recording Apparatus For Diagnosis (AREA)

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• 2002
  • 2002-03-14 DE DE10211766A patent/DE10211766B4/de not_active Expired - Fee Related
• 2003
  • 2003-02-19 MX MXPA04008876A patent/MXPA04008876A/es unknown
  • 2003-02-19 US US10/507,959 patent/US20050125043A1/en not_active Abandoned
  • 2003-02-19 IL IL16400903A patent/IL164009A0/xx unknown
  • 2003-02-19 WO PCT/DE2003/000497 patent/WO2003077985A1/de not_active Ceased
  • 2003-02-19 AU AU2003214006A patent/AU2003214006B2/en not_active Ceased
  • 2003-02-19 DE DE10390950T patent/DE10390950D2/de not_active Expired - Lifetime
  • 2003-02-19 BR BR0308002-1A patent/BR0308002A/pt not_active IP Right Cessation
  • 2003-02-19 JP JP2003576036A patent/JP2005526553A/ja active Pending
  • 2003-02-19 EP EP03709629A patent/EP1483016A1/de not_active Withdrawn
  • 2003-02-19 CA CA002479046A patent/CA2479046A1/en not_active Abandoned

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