Abstract: A method of applying a neural stimulus with an implanted electrode array involves applying a sequence of stimuli configured to yield a therapeutic effect while suppressing psychophysical side effects. The stimuli sequence is configured such that a first stimulus recruits a portion of the fibre population, and a second stimulus is delivered within the refractory period following the first stimulus and the second stimulus being configured to recruit a further portion of the fibre population. Using an electrode array and suitable relative timing of the stimuli, ascending or descending volleys of evoked responses can be selectively synchronised or desynchronised to give directional control over responses evoked.

Abstract: Disclosed is a method of adapting the operation of an implantable device for delivering neurostimulation therapy to a patient. The method comprises: delivering the neurostimulation therapy to electrically excitable tissue of the patient according to at least one therapy parameter; measuring a physiological characteristic of the patient; adjusting the at least one therapy parameter according to a schedule of adjustment and the measured physiological characteristic; and repeating the delivering, measuring, and adjusting.

Abstract: A method of evaluating spinal cord stimulation (SCS), comprising obtaining neural response data generated by a spinal cord stimulator, where the neural response data describes one or more neural signals evoked in the spinal cord of a patient by applying diagnostic stimuli. One or more evoked compound action potentials (ECAPs) associated with the respective one or more neural signals are detected. The one or more detected ECAPs are processed to generate one or more evaluation metrics, and the one or more evaluation metrics are used to generate a confidence score indicating a degree of effectiveness of SCS on the patient.

Abstract: A method for measuring a neural response to a stimulus. Measurement circuitry is settled prior to a stimulus, by connecting a sense electrode to the measurement circuitry to allow the measurement circuitry to settle towards a bio-electrically defined steady state. Charge is recovered on stimulus electrodes by short circuiting the stimulus electrodes to each other. An electrical stimulus is then applied from the stimulus electrodes to neural tissue, while keeping the sense electrode disconnected from the measurement circuitry. After the stimulus, a delay is imposed during which the stimulus electrodes are open circuited and the sense electrode is disconnected from the measurement circuitry and from the stimulus electrodes. After the delay, a neural response signal present at the sense electrode is measured by connecting the sense electrode to the measurement circuitry.

Abstract: Disclosed is an automated programming system for a neuromodulation device that is configured to assist a clinician to efficiently program the neuromodulation device for a particular patient. In particular, the assisted programming system comprises a stimulation user interface control that is configured to cause the intensity of the neural stimulus to ramp up with time as long as the patient continues to interact with the control. The value of stimulus intensity at which the patient ceases to interact with the control is recorded as a significant perceptual marker upon which subsequent steps in the assisted programming workflow are based. This user interface design takes advantage of the human withdrawal reflex, whereby the patient is likely to instinctively release the button upon receiving uncomfortable stimulation. The design therefore minimises the training burden placed on the patient in using the assisted programming system.

Abstract: A method for measuring a neural response to a stimulus. Measurement circuitry is settled prior to a stimulus, by connecting a sense electrode to the measurement circuitry to allow the measurement circuitry to settle towards a bio-electrically defined steady state. Charge is recovered on stimulus electrodes by short circuiting the stimulus electrodes to each other. An electrical stimulus is then applied from the stimulus electrodes to neural tissue, while keeping the sense electrode disconnected from the measurement circuitry. After the stimulus, a delay is imposed during which the stimulus electrodes are open circuited and the sense electrode is disconnected from the measurement circuitry and from the stimulus electrodes. After the delay, a neural response signal present at the sense electrode is measured by connecting the sense electrode to the measurement circuitry.

Abstract: Disclosed are methods and devices for analysing signal windows captured subsequent to delivered neural stimuli and for providing a quality score for each signal window. The quality score is indicative of how closely the captured signal window resembles, or how likely that the captured signal window contains, an ECAP. The quality score may be provided to a process supervising a feedback loop of the closed-loop neural stimulation device delivering the stimuli and capturing the signal windows to ensure the delivered stimuli are appropriate. For example, if the score falls below a predetermined threshold, the supervisor may take a mitigation action to prevent inappropriate adjustment to the intensity of the delivered stimuli by the feedback loop, such as suspending operation of the feedback loop.

Abstract: An implantable device for estimating neural recruitment arising from a stimulus, has a plurality of electrodes. A stimulus source provides stimuli to be delivered from the electrodes to neural tissue. Measurement circuitry obtains a measurement of a neural signal sensed at the electrodes. A control unit is configured to control application of a selected stimulus to neural tissue using the stimulus electrodes; and after the selected neural stimulus, apply a probe stimulus having a short pulse width. A remnant neural response evoked by the probe stimulus is measured; and the control unit estimates from the remnant neural response a neural recruitment caused by the selected neural stimulus.

Abstract: A method of controlling a neural stimulus by use of feedback. The neural stimulus is applied to a neural pathway in order to give rise to an evoked action potential on the neural pathway. The stimulus is defined by at least one stimulus parameter. A neural compound action potential response evoked by the stimulus is measured. From the measured evoked response a feedback variable is derived. A feedback loop is completed by using the feedback variable to control the at least one stimulus parameter value. The feedback loop adaptively compensates for changes in a gain of the feedback loop caused by electrode movement relative to the neural pathway.

Abstract: A method for processing a neural measurement obtained in the presence of artifact, in order to detect whether a neural response is present in the neural measurement. A neural measurement is obtained from one or more sense electrodes. The neural measurement is correlated against a filter template, the filter template comprising at least three half cycles of an alternating waveform, amplitude modulated by a window. From an output of the correlating, it is determined whether a neural response is present in the neural measurement.

Abstract: A neural stimulus comprises at least three stimulus components, each comprising at least one of a temporal stimulus phase and a spatial stimulus pole. A first stimulus component delivers a first charge which is unequal to a third charge delivered by a third stimulus component, and the first charge and third charge are selected so as to give rise to reduced artefact at recording electrodes. In turn this may be exploited to independently control a correlation delay of a vector detector and an artefact vector to be non-parallel or orthogonal.

Abstract: An implantable device for estimating neural recruitment arising from a stimulus, has a plurality of electrodes. A stimulus source provides stimuli to be delivered from the electrodes to neural tissue. Measurement circuitry obtains a measurement of a neural signal sensed at the electrodes. A control unit is configured to control application of a selected stimulus to neural tissue using the stimulus electrodes; and after the selected neural stimulus, apply a probe stimulus having a short pulse width. A remnant neural response evoked by the probe stimulus is measured; and the control unit estimates from the remnant neural response a neural recruitment caused by the selected neural stimulus.

Abstract: A method for processing a neural measurement obtained in the presence of artifact, in order to detect whether a neural response is present in the neural measurement. A neural measurement is obtained from one or more sense electrodes. The neural measurement is correlated against a filter template, the filter template comprising at least three half cycles of an alternating waveform, amplitude modulated by a window. From an output of the correlating, it is determined whether a neural response is present in the neural measurement.

Abstract: Recording evoked neural responses comprises delivering a stimulus from one or more stimulus electrodes to a neural pathway in order to give rise to an evoked compound action potential (ECAP) on the neural pathway. And, recording with measurement circuitry, during delivery of at least part of the stimulus, a neural compound action potential signal sensed at one or more sense electrodes. And, processing the recording of the neural compound action potential signal to determine at least one characteristic of the ECAP. At least one characteristic of the stimulus is then defined based on the determined at least one characteristic of the ECAP.

Abstract: Disclosed is a neurostimulation system comprising: a neuromodulation device for controllably delivering neural stimuli; a headset configured to be worn by the patient and to display images of a virtual object to the patient; one or more sensors configured to perceive a gesture of the patient; and an external computing device. The neuromodulation device comprises: a plurality of implantable electrodes; a stimulus source configured to deliver neural stimuli via selected ones of the implantable electrodes to a neural pathway of a patient; and a control unit configured to control the stimulus source to deliver each neural stimulus according to one or more stimulus parameters. The external computing device comprises a processor in communication with the neuromodulation device, the headset, and the one or more sensors.

Abstract: An implantable device comprising: stimulus electrodes and measurement electrodes; a stimulus source to provide a neural stimulus to be delivered to a neural pathway of a patient to evoke a neural response; measurement circuitry configured to capture a signal window sensed on the neural pathway; and a control unit configured to implement closed-loop neurostimulation therapy by: controlling the stimulus source to provide the neural stimulus according to a stimulus intensity parameter; measuring a characteristic of the signal window; computing a feedback variable from an intensity of an evoked neural response in the signal window; adjusting the stimulus intensity parameter using the feedback variable; and repeating the controlling, measuring, computing, and adjusting to maintain the feedback variable at a target, thereby obtaining multiple measured intensities of neural responses; and computing one or more quantitative indicators of efficacy of the closed-loop neurostimulation therapy using the measured characte

Abstract: A method for determining a desired location at which to apply a neural therapy. An array of electrodes is positioned proximal to neural tissue. A stimulus is applied from the array which evokes a neural compound action potential response in the neural tissue proximal to the array. A plurality of electrodes of the array simultaneously obtain respective measurements of the neural compound action potential response. From the measurements of the neural compound action potential response a desired location for a neural therapy is determined.

Abstract: A neural stimulus comprises at least three stimulus components, each comprising at least one of a temporal stimulus phase and a spatial stimulus pole. A first stimulus component delivers a first charge which is unequal to a third charge delivered by a third stimulus component, and the first charge and third charge are selected so as to give rise to reduced artefact at recording electrodes. In turn this may be exploited to independently control a correlation delay of a vector detector and an artefact vector to be non-parallel or orthogonal.

Abstract: A method for determining a desired location at which to apply a neural therapy. An array of electrodes is positioned proximal to neural tissue. A stimulus is applied from the array which evokes a neural compound action potential response in the neural tissue proximal to the array. A plurality of electrodes of the array simultaneously obtain respective measurements of the neural compound action potential response. From the measurements of the neural compound action potential response a desired location for a neural therapy is determined.

Abstract: There is provided a method and implantable device for controlling a neural stimulus, the neural stimulus being defined by an artefact mitigation status. The method comprises generating a first neural stimulus for delivery to neural tissue, sensing a first signal subsequent to the first neural stimulus, generating a second neural stimulus for delivery to the neural tissue, and sensing a second signal subsequent to the second neural stimulus. The method further comprises determining an artefact mitigation measure (AMM) effect level based on the first sensed signal and the second sensed signal, and setting, in response to comparing the AMM effect level with an AMM effect threshold, the artefact mitigation status of a third neural stimulus to active.