Patent classifications
A61N1/36125
Pulsed passive charge recovery circuitry for an implantable medical device
The problem of a potentially high amount of supra-threshold charge passing through the patient's tissue at the end of an Implantable Pulse Generator (IPG) program is addressed by circuitry that periodically dissipates only small amount of the charge stored on capacitances (e.g., DC-blocking capacitors) during a pulsed post-program recovery period. This occurs by periodically activating control signals to turn on passive recovery switches to form a series of discharge pulses each dissipating a sub-threshold amount of charge. Such periodic pulsed dissipation may extend the duration of post-program recovery, but is not likely to be noticeable by the patient when the programming in the IPG changes from a first to a second program. Periodic pulsed dissipation of charge may also be used during a program, such as between stimulation pulses.
Use of charge imbalanced pulses in an implantable stimulator to effect a pseudo-constant DC current bias
Techniques are described for providing a therapeutic pseudo-constant DC current in an implantable stimulator using pulses whose positive and negative phases are not charge balanced. Such charge imbalanced pulses act to charge any capacitance in the current path between selected electrode nodes, such as the DC-blocking capacitors and/or any inherent capacitance such as those present at the electrode/tissue interface. These charged capacitances act during quiet periods between the pulses to induce a pseudo-constant DC current. Beneficially, these DC currents can be small enough to stay within charge density limits and hence not corrode the electrode or cause tissue damage, and further can be controlled to stay within such limits or for other reasons. Graphical user interface (GUI) aspects for generating the charge imbalanced pulses and for determining and/or controlling the pseudo-constant DC current are also provided.
ACTIVE IMPLANTABLE STIMULATING DEVICE FOR ON-DEMAND STIMULATION OF A VAGUS NERVE
An active implantable stimulating device (10) includes: (a) a tissue coupling unit (40) for being implanted directly onto a vagus nerve (Vn) of a patient, (b) an EEG-unit (70) for measuring an electroencephalogram of the patient, (c) an encapsulation unit (50) configured for being subcutaneously implanted, (d) an energy transfer lead (30) for transferring pulses of electrical and/or optical energy, (e) a signal transfer lead (60) for transferring signals between the EEG unit and the encapsulation unit. EEG electrodes (70a-70d) monitor the electric activity of the brain of a patient. The EEG signal is conveyed to the electronic circuit (53) in the form of EEG conditioned data. The electronic circuit analyses the EEG conditioned data to yield analysis results. The electronic circuit takes a decision to trigger energy pulses to stimulate the vagus nerve (VN).
Implantable pulse generator carrier used to interface with multiple lead sizes
An apparatus and method of electrically coupling a previously implanted stimulation lead with a replacement neurostimulator device. The apparatus and method configured to operably couple a proximal portion of a neuromodulation adapter including a plurality of electrical conductors spaced apart at a first pitch spacing to a corresponding plurality of electrical terminals of a replacement neurostimulator device, and operably couple a distal end of the neuromodulation adapter including a plurality of conductor elements and an electrically active set screw spaced part of a second pitch spacing to a corresponding plurality of electrical connectors of a previously implanted stimulation lead.
Current generation architecture for an implantable medical device
An implantable pulse generator (IPG) is disclosed having a plurality of electrode nodes, each electrode node configured to be coupled to an electrode to provide stimulation pulses to a patient's tissue. The IPG includes a digital-to-analog converter configured to amplify a reference current to a first current specified by first control signals; a first resistance configured to receive the first current, wherein a voltage across the first resistance is held to a reference voltage at a first node; a plurality of branches each comprising a second resistance and configured to produce a branch current, wherein a voltage across each second resistance is held to the reference voltage at second nodes; and a switch matrix configurable to selectively couple any branch current to any of the electrode nodes via the second nodes.
Implantable Electro-Medical Device Programmable for Improved Operational Life
A device for electrically stimulating one or more anatomical target sites in a patient and for use in the treatment of a plurality of biological conditions of the patient. The device has a pulse generator providing electrical stimulation to the anatomical target sites; a power source for powering the pulse generator; stimulator electrodes connected to the pulse generator for stimulating the anatomical target sites; one or more optional sensing electrodes for monitoring physiological parameters with reference to the anatomical target sites; and a microprocessor programmed to vary a plurality of therapy protocol parameters governing the electrical stimulation to thereby modify operational life parameters of the power source.
Methods and systems for treating cardiovascular disease using an implantable electroacupuncture device
A method of treating cardiovascular disease in a patient includes generating, by an implantable stimulator configured to be implanted beneath a skin surface of the patient, stimulation sessions at a duty cycle that is less than 0.05 and applying, by the implantable stimulator in accordance with the duty cycle, the stimulation sessions to a location, within the patient, that is associated with the cardiovascular disease. The duty cycle is a ratio of T3 to T4. Each stimulation session included in the stimulation sessions has a duration of T3 minutes and occurs at a rate of once every T4 minutes.
Spinal cord stimulation with interferential current using multiple beat signals
A method for spinal cord stimulation treatment includes positioning eight implantable electrodes to a dura matter in an epidural space proximate to a subject's spinal cord so that (i) a first circuit is created between a first and second electrode on a first channel, (ii) a second circuit is created between a third and fourth electrode on a second channel, (iii) a third circuit is created between a fifth and sixth electrode on a third channel, and (iv) a fourth circuit is created between a seventh and eighth electrode on a fourth channel, transmitting signals through the first and second circuits that interfere to produce a first beat signal, transmitting signals through the third and fourth circuits that interfere to produce a second beat signal, and interaction of the first and second beat signals results in a combined beat signal proximate to the subject's spinal cord.
Analyzing ECAP signals
Systems, devices, and techniques are configured for analyzing evoked compound action potentials (ECAP) signals to assess the effect of a delivered electrical stimulation signal. In one example, a system includes processing circuitry configured to receive ECAP information representative of an ECAP signal sensed by sensing circuitry, and determine, based on the ECAP information, that the ECAP signal includes at least one of an N2 peak, P3 peak, or N3 peak. The processing circuitry may then control delivery of electrical stimulation based on at least one of the N2 peak, P3 peak, or N3 peak.
Power Efficient Stimulators
This disclosure relates to a device for applying a neural stimulus. A battery supplies electrical energy at a battery voltage and an electrode applies the electrical energy to neural tissue. A circuit measures the nervous response of the tissue and a voltage converter receives the electrical energy from the battery and controls a voltage applied to the electrode based on the measured nervous response of the tissue. This direct voltage control is energy efficient because losses across a typical current mirror are avoided. Further, the control based on the measured nervous response leads to automatic compensation of impedance variation due to in-growth or change in posture. As a result, the stimulation results in a desired neural response.