Abstract: Methods and systems for programming stimulation parameters for an implantable medical device for neuromodulation, such as spinal cord stimulation (SCS) are disclosed. The stimulation parameters define user-configured waveforms having at least a first phase having a first polarity and a second phase having a second polarity, wherein the first and second phases are separated by an interphase interval (IPI). By delivering user-configured waveforms with different IPIs, stimulation geometry, and other waveform settings, therapeutic asynchronous activation of dorsal column fibers can be obtained.

Abstract: Methods and systems for proving spinal cord stimulation (SCS) for treating pain in a patient are described. Embodiments of the described methods and systems can provide sub-perception SCS that has a fast wash-in time by using stimulation parameters that activate surround inhibition in the patient. Measuring retrograde potentials evoked by the stimulation can be performed to facilitate choosing the best stimulation parameters, in particular, the best stimulating electrode contact configurations for activating surround inhibition. For example, peripheral electrodes may be placed at the center of the patient's pain (within a local receptive field (LRF), with respect to the patient's pain center) and within an area surrounding the patient's pain center (within a surrounding receptive field (SRF), with respect to the patient's pain center). Retrograde evoked potentials measured and the SRF and/or the LRF can be used to guide the selection of the stimulation parameters.

Abstract: 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.

Abstract: An example of a system for delivering neurostimulation may include a programming control circuit and a stimulation control circuit. The programming control circuit may be configured to generate stimulation parameters controlling delivery of the neurostimulation according to a stimulation configuration. The stimulation control circuit may be configured to specify the stimulation configuration, and may include volume definition circuitry and stimulation configuration circuitry. The volume definition circuitry may be configured to determine one or more test volumes, determine a clinical effect resulting from the one or more test volumes each being activated by the neurostimulation, and determine a target volume using the determined clinical effect. The stimulation configuration circuitry may be configured to generate the specified stimulation configuration for activating the target volume.

Abstract: A system and method for extracting a cardiac signal from a spinal signal include measuring a spinal signal at one or more electrodes that are connected to a neurostimulator and implanted within a patient's spinal canal and processing the spinal signal to extract the cardiac signal, which includes features that are representative of the patient's cardiac activity. Processing the spinal signal to extract the cardiac signal can include filtering the spinal signal, or use of model reduction schemes such as independent component analysis. The extracted cardiac signal can include a number of features that correspond to an electrocardiogram and can be used to determine the patient's heart rate and/or to detect a cardiac anomaly. Cardiac features that are determined from the cardiac signal can additionally be used to adjust parameters of the stimulation that is provided by the neurostimulator.

Abstract: An example of a system for delivering neurostimulation energy may include a programming control circuit and a user interface. The programming control circuit may be configured to generate stimulation parameters according to a neurostimulation program including a pattern of interferential stimulation configured to effect asynchronous and/or non-regular activation of nerve fibers by simultaneously delivering a first stimulation current having a first waveform with a first frequency using a first electrode configuration and a second stimulation current having a second waveform with a second frequency using a second electrode configuration.

Abstract: A method for estimating neural activation arising from stimulation by a stimulation system includes identifying different neural elements stimulated by the stimulation; obtaining a neural response signal resulting from the stimulation by the stimulation system; and decomposing the neural response signal to estimate neural activation of each of the different neural elements.

Abstract: An example of a system for delivering neurostimulation may include a programming control circuit and a stimulation control circuit. The programming control circuit may be configured to generate stimulation parameters controlling delivery of the neurostimulation according to a stimulation configuration. The stimulation control circuit may be configured to specify the stimulation configuration, and may include volume definition circuitry and stimulation configuration circuitry. The volume definition circuitry may be configured to determine one or more test volumes, determine a clinical effect resulting from the one or more test volumes each being activated by the neurostimulation, and determine a target volume using the determined clinical effect. The stimulation configuration circuitry may be configured to generate the specified stimulation configuration for activating the target volume.

Abstract: An example of a neurostimulation system may include a storage device for storing data representing physiological signals and a user interface including a user input, a display screen, and a presentation control circuit. The user input may be configured to receive a selection of signal(s) from the physiological signals and a selection of viewing mode from viewing modes including a metric mode and/or a presence mode. The metric mode allows for visualization of a signal property indicated by a parameter measured from the selected signal(s). The presence mode allows for viewing presence of a feature in the selected signal(s). The presentation control circuit may be configured to allow for the selection of the signal(s) and the viewing mode, to determine a segment of each of the selected signal(s) for presentation according to the selected viewing mode, and to present the determined segment on the display screen.

Abstract: A system may include a stimulator, sensing circuitry and a controller. The stimulator may be operably connected to at least one stimulation electrode, and configured to deliver an electrical waveform for an electrical therapy using the at least one stimulation electrode. The sensing circuitry may be operably connected to at least one sensing electrode, and configured to sense electrical potentials that are evoked by the electrical waveform to provide sensed evoked signals. The controller may be operably connected to the stimulator and the sensing circuitry. The controller may be configured to automatically define a sampling window, sample the sensed evoked potentials during the sampling window to provide sampled values, detect at least one feature from the sampled values, and automatically provide feedback for closed-loop control of the electrical therapy based on the at least one feature.

Abstract: A fitting algorithm for a spinal cord stimulator is disclosed, which is preferably implemented in a clinician programmer having a graphical user interface. In one example, coupling parameters indicative of coupling to neural structures are determined for each electrode in an implanted electrode array. The user interface associates different pole configurations with different anatomical targets and with different measurement techniques (subjective or objective) to gauge the effectiveness of the pole configuration at different positions in the electrode array. The pole configuration, perhaps as modified by the coupling parameters, is then steered in the array, and effectiveness is measured along with a paresthesia threshold at each position. Using at least this data, the fitting algorithm can determine one or more candidate positions in the electrode array at which a therapeutic stimulation program can be centered.

Abstract: An example of a neurostimulation system may include a programming control circuit, a sensing circuit, and a stimulation control circuit. The programming control circuit may be configured to generate stimulation parameters controlling delivery of neurostimulation according to stimulation waveform(s) and stimulation field(s). The sensing circuit may be configured to sense signals. The stimulation control circuit may be configured to determine the stimulation waveform(s) and the stimulation field(s) based on a lead configuration and may be configured to determine first and second electrodes of respective first and second leads, receive first and second signals sensed using the first and second electrodes, detect corresponding signal features from the first and second signals, determine a feature delay between the detected signal features, and determine a need for adjusting the lead configuration using the feature delay. The signal features are associated with a response of the patient to the neurostimulation.

Abstract: A system may include electrodes on at least one lead configured to be operationally positioned for use in modulating a volume of neural tissue, a neural modulation generator configured to deliver energy using at least some electrodes to modulate the volume of neural tissue, a programming system configured to program the programmed modulation parameter set, including determine electrode fractionalizations for the electrodes based on a target multipole. The programmed parameter set may include the determined electrode fractionalizations. The target multipole may be used to determine electrode fractionalizations having at least three target poles that directionally and progressively stack fractionalizations of target poles to provide a linear electric field over the volume of tissue. The neural modulation generator may be configured to use the programmed modulation parameter set to provide the linear electric field over the volume of tissue.

Abstract: Methods and systems are described for detecting if a stimulation lead implanted in a patient's brain has moved. Lead movement occurring between a first time and a second time may be determined by comparing features extracted from evoked potentials recorded at the two times. The disclosed methods and systems are particularly useful for determining if a stimulation lead has moved between the time it was implanted in the patient's brain and the time that stimulation parameters are being optimized. Lead movement during implantation, during parameter optimization, and during or between other lead optimization processes may be determined as well.

Abstract: Methods and systems for using sensed neural responses for informing aspects of stimulation therapy are disclosed. For example, features of evoked neural responses, such as evoked compound action potentials (ECAPs) can be used for closed-loop feedback control of stimulation parameters. Aspects of the disclosed methods and systems can differentiate between changes in the sensed neural responses that are caused by the environment at stimulating electrodes and changes in the neural responses that are caused by the environment at sensing electrodes. Embodiments determine changes in the morphology of the neural responses, which morphology changes indicate a degree of change in the stimulating environment. Algorithms and systems for assigning and tracking likelihoods for underlying electrode-tissue changes based on sensed neural responses are disclosed. The feedback control modality may be updated based on such likelihoods.

Abstract: A fitting algorithm for a spinal cord stimulator is disclosed, which is preferably implemented in a clinician programmer having a graphical user interface. In one example, coupling parameters indicative of coupling to neural structures are determined for each electrode in an implanted electrode array. The user interface associates different pole configurations with different anatomical targets and with different measurement techniques (subjective or objective) to gauge the effectiveness of the pole configuration at different positions in the electrode array. The pole configuration, perhaps as modified by the coupling parameters, is then steered in the array, and effectiveness is measured along with a paresthesia threshold at each position. Using at least this data, the fitting algorithm can determine one or more candidate positions in the electrode array at which a therapeutic stimulation program can be centered.

Abstract: Systems and methods for optimizing neuromodulation field design for pain therapy are discussed. An exemplary neuromodulation system includes an electrostimulator to stimulate target tissue to induce paresthesia, a data receiver to receive pain data including pain sites experiencing pain, and to receive patient feedback on the induced paresthesia including paresthesia sites experiencing paresthesia. The neuromodulation system includes a processor circuit configured to generate a spatial correspondence indication between the pain sites and the paresthesia sites over one or more dermatomes, determine an anodic weight and a cathodic weight for each of multiple electrode locations using the spatial correspondence indication, and generate a stimulation field definition for neuromodulation pain therapy.

Abstract: A system may include electrodes on at least one lead configured to be operationally positioned for use in modulating a volume of neural tissue, a neural modulation generator configured to deliver energy using at least some electrodes to modulate the volume of neural tissue, a programming system configured to program the programmed modulation parameter set, including determine electrode fractionalizations for the electrodes based on a target multipole. The programmed parameter set may include the determined electrode fractionalizations. The target multipole may be used to determine electrode fractionalizations having at least three target poles that directionally and progressively stack fractionalizations of target poles to provide a linear electric field over the volume of tissue. The neural modulation generator may be configured to use the programmed modulation parameter set to provide the linear electric field over the volume of tissue.

Abstract: Systems and methods for providing stimulation and neural response sensing in an implantable stimulation device are disclosed. A neural response database records baseline neural response information from one or more sensing electrodes for a given pole configuration that provides stimulation to a patient. The stimulation device can then take neural response measurements at the sensing electrode(s) and the system (possibly with the assistance of an external device in communication with the stimulation device) can compare the neural response measurements with the baselines. If they differ, as they might if the electrode array has moved in the patient's tissue, an algorithm can be used to move the position of the pole configuration in the electrode array to cause the neural response measurements to equal, or at least come closer to, the neural response baselines.

Abstract: Systems and methods for applying electrical stimulation to different sub-populations of targeted neurological tissue for optimizing spinal cord stimulation are disclosed. According to an aspect, a method includes applying a first pattern of electrical stimulation to a first sub-population of targeted neurological tissue of a subject. The method also includes applying a second pattern of electrical stimulation to a second sub-population of targeted neurological tissue of the subject, the second pattern of electrical stimulation being applied at a different frequency than the first pattern of electrical stimulation.