Abstract: This document discusses a medical system for coupling to one or more implantable electrodes. The medical system includes a sensing circuit, memory, and processing circuitry. The sensing circuit is configured to sense one or more neural signal representative of neural activity of a subject when connected to an implantable electrode of the one or more implantable electrodes, and the memory is to store a reference signal that is representative of a neural response associated with a state of arousal at or near an anatomical location of the implantable electrode. The processing circuitry is configured to compare the one or more sensed neural signals to the reference signal, and to determine a depth of anesthesia of the subject according to the comparison of the one or more sensed neural signals and the reference signal.

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: A compliance voltage management algorithm is disclosed for managing the compliance voltage, VH, that powers the DAC circuitry in a stimulator device. A user can use a user interface associated with an external programming device to define a time-varying stimulation waveform to be programmed into the stimulator device. The algorithm analyzes the prescribed waveform and determines a number of groups of pulses that will be treated similarly from a VH management standpoint. Optimal compliance voltages are determined for each group, as are the rise and fall rates at which VH is able to change at transitions between groups. These rise or fall rates in VH are then used to set when the compliance voltage should increase or decrease. For example, the algorithm will automatically set VH to start rising in advance of a transition so that it is at the proper higher value when the transition occurs.

Abstract: Methods and systems for using sensed evoked neural responses for informing aspects of neurostimulation therapy are disclosed. Electrical signals may be recorded during the provision of electrical stimulation to a patient's neural tissue. The electrical signals may be processed and analyzed using one or more classification criteria to determine if the electrical signals contain a neural response of interest. Examples of such neural responses include evoked neural responses that are oscillatory and/or resonant in nature. If the electrical signals include such responses of interest, one or more features may be extracted from the signals and used as biomarkers for informing aspects of neurostimulation therapy, such as directing lead placement, optimizing stimulation parameters, closed-loop feedback control of stimulation, and the like. Various methods and systems described herein are particularly relevant in the context of multi-site stimulation paradigms, such as coordinated reset neuromodulation.

Abstract: A system for estimating a volume of activation around an implanted electrical stimulation lead for a set of stimulation parameters includes a display; and a processor coupled to the display and configured to: receive a set of stimulation parameters including a stimulation amplitude and a selection of one of more electrodes of the implanted electrical stimulation lead for delivery of the stimulation amplitude; determine an estimate of the volume of activation based on the set of stimulation parameters using the stimulation amplitude and a database including a plurality of planar distributions of stimulation threshold values and a map relating the planar distributions to spatial locations based on the one or more electrodes of the implanted electrical stimulation lead selected for delivery of the stimulation amplitude; and output on the display a graphical representation of the estimate of the volume of activation.

Abstract: An example of a system for delivering neurostimulation using a stimulation device and controlling the delivery of the neurostimulation may include a programming control circuit and a stimulation control circuit. The programming control circuit may be configured to program the stimulation device for delivering the neurostimulation according to a pattern of neurostimulation pulses defined by one or more stimulation waveforms. The stimulation control circuit may be configured to determine the pattern of neurostimulation pulses with the one or more stimulation waveforms constrained by one or more thresholds, and may include threshold circuitry that may be configured to receive one or more known values of the one or more thresholds and to determine needed values of the one or more thresholds by executing an algorithm allowing for prediction of the needed values of the one or more thresholds based on the one or more known values.

Abstract: A system for estimating a volume of activation around an implanted electrical stimulation lead for a set of stimulation parameters includes a display; and a processor coupled to the display and configured to: receive a set of stimulation parameters including a stimulation amplitude and a selection of one of more electrodes of the implanted electrical stimulation lead for delivery of the stimulation amplitude; determine an estimate of the volume of activation based on the set of stimulation parameters using the stimulation amplitude and a database including a plurality of planar distributions of stimulation threshold values and a map relating the planar distributions to spatial locations based on the one or more electrodes of the implanted electrical stimulation lead selected for delivery of the stimulation amplitude; and output on the display a graphical representation of the estimate of the volume of activation.

Abstract: An example of a system for delivering neurostimulation using a stimulation device and controlling the delivery of the neurostimulation may include a programming control circuit and a stimulation control circuit. The programming control circuit may be configured to program the stimulation device for delivering the neurostimulation according to a pattern of neurostimulation pulses defined by one or more stimulation waveforms. The stimulation control circuit may be configured to determine the pattern of neurostimulation pulses with the one or more stimulation waveforms constrained by one or more thresholds, and may include threshold circuitry that may be configured to receive one or more known values of the one or more thresholds and to determine needed values of the one or more thresholds by executing an algorithm allowing for prediction of the needed values of the one or more thresholds based on the one or more known values.

Abstract: Systems and methods for determining a parameter set and programming a neuromodulation system with the parameter set are disclosed. The system includes a user interface having a display screen to display simplified graphical representations (SGRs) of the lead with at least one virtual electrode (VE) that represents one or more electrodes, and control elements. The SGRs of the lead can provide longitudinal and circumferential representations of the VE, respectively representing longitudinal or circumferential position, size, shape, or spread of the VE. The control elements may include longitudinal and circumferential control elements to enable the user to respectively adjust the longitudinal or circumferential position, size, shape, or spread of the VE. The system may generate the neuromodulation parameter set using the longitudinal and circumferential representations of the VE, and program the neuromodulation system with the neuromodulation parameter set.

Abstract: This document discusses, among other things, systems and methods for delivering electrostimulation to specific tissue of a patient. An example of a system can receive a three-dimensional voxelized model representing a plurality of regions each specified as a target region or an avoidance region. The system includes control circuitry to determine a metric value using the voxelized model. The metric value indicates a clinical effect of electrostimulation on the plurality of regions according to a stimulation current and a current fractionalization. The control circuitry can determine a desired stimulation current that results in a first metric value satisfying a clinical effect condition. The system can generate a stimulation configuration including the desired stimulation current and the current fractionalization corresponding to the first metric value, and deliver tissue stimulation according to the stimulation configuration.

Abstract: A system or method for identifying sets of stimulation parameters can include receiving at least one image of a region of a patient; registering the at least one image with an anatomical or physiological atlas that identifies different anatomical or physiological structures; identifying a desired stimulation region using the at least one image; comparing the desired stimulation region with each of a plurality of predetermined estimated stimulation regions, where each of the estimated stimulation regions is a calculated estimate of a stimulation volume for a corresponding set of electrical stimulation parameters; selecting one of the predetermined estimated stimulation regions based on the comparing; and providing the corresponding set of electrical stimulation parameters for the selected one of the predetermined estimated stimulation regions to a user or an electrical stimulation device.

Abstract: Methods and systems for selecting stimulation parameters using targeting and steering techniques are presented. For example, a method or system (via actions performed by a processor) can include receiving a name of an anatomical or physiological target or a name of a disease or disorder; receiving a clinical goal; and using at least 1) the anatomical or physiological target or disease or disorder and 2) the clinical goal, selecting a set of stimulation parameters. Another method or system (via actions performed by its processor) can include receiving a first set of stimulation parameters; receiving a command to alter the first set of stimulation parameters that does not include, or is not composed exclusively of, a numerical value for any of the stimulation parameters; and modifying the first set of stimulation parameters to create a second set of stimulation parameters based on the command.

Abstract: Implantable medical devices (IMD) such as those used in Deep Brain Stimulation application are commonly replaced when the device's useful life expires. At the time of replacement, the electrodes that were connected to the initial IMD are typically reused with the replacement IMD. It is desirable for the replacement IMD to utilize the stimulation parameters that were being utilized to provide stimulation in the initial IMD, but it is important that the electrodes be connected to the replacement IMD in a similar manner as they were connected to the initial IMD if stimulation parameters are reused. A connected electrode profile that includes measurements of electrical parameters associated with the electrodes can be generated in the initial IMD and the replacement IMD, and the profiles can be compared to determine whether the electrodes are connected in a similar manner in the replacement IMD as they were in the initial IMD.

Abstract: Incorrect connection or mapping of leads' proximal terminals to the ports of an Implantable Stimulator Device (ISD), such as an implantable pulse generator or an external trial stimulator, is a concern, and this disclosure is directed to use of measurement and identification algorithms to either determine that leads are properly connected to their assigned ISD ports, or to determine which leads are connected to the ports even if the leads are not preassigned to the ports. Particular focus is given in the disclosed technique to assessing leads that comprise larger number of electrodes than are supported at each port, and thus have more than one proximal terminal that connect to more than one port of the ISD.

Abstract: A system or method for identifying sets of stimulation parameters can include receiving at least one image of a region of a patient; registering the at least one image with an anatomical or physiological atlas that identifies different anatomical or physiological structures; identifying a desired stimulation region using the at least one image; comparing the desired stimulation region with each of a plurality of predetermined estimated stimulation regions, where each of the estimated stimulation regions is a calculated estimate of a stimulation volume for a corresponding set of electrical stimulation parameters; selecting one of the predetermined estimated stimulation regions based on the comparing; and providing the corresponding set of electrical stimulation parameters for the selected one of the predetermined estimated stimulation regions to a user or an electrical stimulation device.

Abstract: Methods and systems for selecting stimulation parameters using targeting and steering techniques are presented. For example, a method or system (via actions performed by a processor) can include receiving a name of an anatomical or physiological target or a name of a disease or disorder; receiving a clinical goal; and using at least 1) the anatomical or physiological target or disease or disorder and 2) the clinical goal, selecting a set of stimulation parameters. Another method or system (via actions performed by its processor) can include receiving a first set of stimulation parameters; receiving a command to alter the first set of stimulation parameters that does not include, or is not composed exclusively of, a numerical value for any of the stimulation parameters; and modifying the first set of stimulation parameters to create a second set of stimulation parameters based on the command.

Abstract: Implantable medical devices (IMD) such as those used in Deep Brain Stimulation application are commonly replaced when the device's useful life expires. At the time of replacement, the electrodes that were connected to the initial IMD are typically reused with the replacement IMD. It is desirable for the replacement IMD to utilize the stimulation parameters that were being utilized to provide stimulation in the initial IMD, but it is important that the electrodes be connected to the replacement IMD in a similar manner as they were connected to the initial IMD if stimulation parameters are reused. A connected electrode profile that includes measurements of electrical parameters associated with the electrodes can be generated in the initial IMD and the replacement IMD, and the profiles can be compared to determine whether the electrodes are connected in a similar manner in the replacement IMD as they were in the initial IMD.

Abstract: Incorrect connection or mapping of leads' proximal terminals to the ports of an Implantable Stimulator Device (ISD), such as an implantable pulse generator or an external trial stimulator, is a concern, and this disclosure is directed to use of measurement and identification algorithms to either determine that leads are properly connected to their assigned ISD ports, or to determine which leads are connected to the ports even if the leads are not preassigned to the ports. Particular focus is given in the disclosed technique to assessing leads that comprise larger number of electrodes than are supported at each port, and thus have more than one proximal terminal that connect to more than one port of the ISD.

Abstract: An example of a system for delivering neurostimulation may include a display and an interface control circuit. The interface control circuit may be configured to define a stimulation waveform according to which the neurostimulation is delivered. The stimulation waveform is defined by waveform parameters including one or more user-adjustable parameters. The interface control circuit may include a parameter selector, an effect analyzer, and a parameter generator. The parameter selector may be configured to present values for each user-adjustable parameter on the display and allow the user to select a value for each user-adjustable parameter from the presented values. The effect analyzer may be configured to estimate an interactive effect of different stimuli of the neurostimulation. The parameter generator may be configured to select a rate rule based on the estimated interactive effect and to generate the values for each user-adjustable parameter according to the selected rate rule.

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.