Systems and methods for delivering sub-threshold therapy to a patient

Abstract

Systems and methods for delivering sub-threshold therapy to a patient are provided, in which an external control device for programming an implantable neurostimulator coupled to an electrode array implanted within a patient is provided, comprising: a user interface; a telemetry circuit configured to communicate with the neurostimulator; and a controller / processor circuit configured to, in response to input to the user interface, direct the neurostimulator via the telemetry circuit to deliver super-threshold electrical modulation energy according to a set of super-threshold modulation parameters and to deliver sub-threshold electrical modulation energy according to a set of sub-threshold modulation parameters, wherein the super-threshold modulation program and the sub-threshold modulation program are contained in a hybrid modulation program. A neurostimulation system is also provided.

Description

[0001] This application is a divisional application of the application filed on March 15, 2014, with application number 201480026970.7 and invention title "System and Method for Delivering Subthreshold Therapy to a Patient". Technical Field

[0002] This invention relates to tissue modulation systems, and more particularly to programmable neural modulation systems. Background Technology

[0003] Implantable neuromodulation systems have proven effective for a variety of conditions and discomforts. Pacemakers and implantable cardioverter-defibrillators (ICDs) have proven highly effective in treating some cardiac conditions, such as arrhythmias. Spinal cord stimulation (SCS) systems have long been accepted as a treatment for chronic pain syndromes, and the application of tissue stimulation is beginning to expand to additional uses, such as angina and incontinence. Deep brain stimulation (DBS) has been used to treat refractory chronic pain syndromes for over a decade, and DBS has recently been applied to additional areas, such as movement disorders and epilepsy. Furthermore, in recent investigations, peripheral nerve stimulation (PNS) systems have proven effective in treating chronic pain syndromes and incontinence, and several additional applications are currently under investigation. In addition, functional electrical stimulation (FES) systems, such as NeuroControl's "Freehand" system (located in Cleveland, Ohio), have been used to restore some function to paralyzed limbs in patients with spinal cord injuries.

[0004] These implantable neuromodulation systems typically include one or more electrodes carrying modulation leads implanted at the desired modulation site, and a neuromodulator (e.g., an implantable pulse generator (IPG)) implanted remotely from the modulation site but directly coupled to one or more modulation leads or indirectly coupled to one or more modulation leads via lead extensions. The neuromodulation system may also include a handheld external control device (e.g., remote control (RC)) to remotely guide the neuromodulator to generate electrically modulated pulses according to selected modulation parameters.

[0005] Implantable neuromodulation devices are active devices that require energy to operate, and therefore, neuromodulation systems often include an external charger to recharge the neuromodulation device, thus avoiding the need for surgery to replace the device when it is depleted of power. To wirelessly transfer energy between the external charger and the implanted neuromodulation device, the charger typically includes an AC charging coil that powers a similar charging coil placed in or on the neuromodulation device. The energy received by the charging coil on the neuromodulation device can then be stored in a rechargeable battery within the device, which can then be used to power electronic components as needed. Depending on the setup, the neuromodulation device may require recharging every 1 to 30 days.

[0006] Electrically modulated energy can be delivered from a neurostimulator to electrodes in the form of electrical pulse waveforms. Therefore, electrically modulated energy can be controllably delivered to electrodes to modulate neural tissue. The configuration of electrodes used to deliver electrical pulses to the target tissue constitutes an electrode configuration, which can be selectively programmed to function as an anode (positive), cathode (negative), or off (zero). In other words, the electrode configuration represents polarity as positive, negative, or zero. Other parameters that can be controlled or varied include the amplitude, width, and rate of the electrical pulses provided by the electrode array. Each electrode configuration, along with the electrical pulse parameters, can be referred to as a "modulation parameter set."

[0007] For some neural modulation systems, especially those with independently controlled current or voltage sources, the distribution of current to electrodes (including in the case of neural modulators, which can be used as electrodes) can be altered so that current is provided through a large number of different electrode configurations. In different configurations, electrodes can provide current or voltage at different relative percentages of positive current or voltage and negative current or voltage to create different current distributions (i.e., subdivided electrode configurations).

[0008] As discussed in the simplified manner above, an external control device can be used to instruct the neuromodulation device to generate electrical pulses according to selected modulation parameters. Typically, the modulation parameters programmed into the neuromodulation device can be adjusted by manipulating controls on the external control device to modify the electrical modulated energy delivered to the patient by the neuromodulation device system. Therefore, based on the modulation parameters programmed by the external control device, electrical pulses can be delivered from the neuromodulation device to one or more electrodes to modulate tissue volume according to a set of modulation parameters and provide the desired effective treatment to the patient. The optimal set of modulation parameters will typically be one that delivers electrical energy to the tissue volume that must be modulated to provide therapeutic benefits (e.g., pain management) while minimizing the amount of non-target tissue volume modulated.

[0009] However, the combination of the number of available electrodes and the ability to generate a wide variety of complex electrical pulses presents clinicians or patients with a vast selection of modulation parameter sets. For example, if a neural modulation system to be programmed has a sixteen-electrode array, millions of modulation parameter sets can be used to program the neural modulation system. Today, neural modulation systems can have up to thirty-two electrodes, thus exponentially increasing the number of modulation parameter sets available for programming.

[0010] To facilitate this choice, clinicians typically program neural modulation devices using computerized programming systems. These systems can be self-contained hardware / software systems or primarily defined by software running on a standard personal computer (PC). The PC or client hardware can actively control the characteristics of the electrical impulses generated by the neural modulation device, allowing optimal modulation parameters to be determined based on patient feedback or other means, and subsequently used to program the neural modulation device using this optimal set of modulation parameters. Computerized programming systems can be operated by clinicians caring for patients in several scenarios.

[0011] For example, to achieve effective results from a traditional SCS, one or more leads must be positioned so that electrical modulation (and in this case, electrical stimulation) will induce a sensory abnormality. The sensory abnormality induced by the stimulation and perceived by the patient should be located approximately in the same location within the patient's body as the pain being treated. If the leads are not positioned accurately, the patient may receive less or no benefit from the implanted SCS system. Therefore, accurate lead placement can mean the difference between effective and ineffective pain management. When the leads are implanted in the patient, a computerized programming system within the context of an operating room (OR) mapping procedure can be used to instruct the neuromodulation device to apply electrical stimulation to test the placement of the leads and / or electrodes, thereby ensuring the effective positioning of the leads and / or electrodes within the patient.

[0012] Once the lead has been accurately positioned, a computerized programming system can be used to execute a fitting procedure (which may be called a navigation session) to program the external control device and (if applicable) the neuromodulation device using the set of modulation parameters best suited to address the pain location. Thus, the navigation session can be used to identify the amount of activation (VOA) or region associated with pain. These programming capabilities are particularly advantageous when targeting the tissue during or after implantation, where the lead should be gradually or undesirably moved away from the target location to reposition the stimulation energy. By reprogramming the neuromodulation device (typically by independently changing the stimulation energy on the electrodes), the amount of activation (VOA) can typically be moved back to the effective pain location without necessarily requiring reoperation with the patient to reposition the lead and its electrode array. When adjusting the amount of activation (VOA) relative to the tissue, it is desirable to make small changes proportional to the current, allowing the patient to perceive changes in the spatial recruitment of nerve fibers as smooth, continuous, and with an increasing targeting ability.

[0013] A known computerized programming system for SCS is called a bionic system that can be purchased from Boston Scientific Neuromodulation. (Bionic Bionics The software package operates on a suitable PC and allows clinicians to program modulation parameters to an external handheld programmer (referred to as remote control). Each set of modulation parameters, including the subdivided current distribution to the electrodes (as percentage cathode current, percentage anode current, or off), can be stored in the bionic... And in remote control, and combined into a stimulation program, which can then be used to stimulate multiple areas within the patient.

[0014] In order to determine the modulation parameters to be programmed, bionics The procedure can be operated by the clinician in one of three modes: (a) a manual programming mode that allows manual selection of the cathode and anodic currents flowing through the electrodes; (b) an electronic troll mode that uses a limited number of electrode configurations to rapidly scan the electrode array to progressively move the cathode under bipolar stimulation; and (c) a navigation programming mode that uses a larger number of electrode configurations to fine-tune and optimize stimulation coverage for patient comfort. These three modes allow the clinician to determine the most effective set of modulation parameters for a given patient.

[0015] In manual programming mode, clinicians directly select individual electrodes and the current amplitude and polarity to be applied to each selected electrode. In e-troll mode and navigation programming mode, the bionic... Semi-automatic switching between different electrode configurations allows for the systematic, real-time "guiding" of current along the implanted electrodes (e.g., using joystick or similar control). This enables clinicians to determine the most effective set of modulation parameters, which can then be stored and ultimately combined into a stimulation program. In the context of SCS, current guidance is typically performed in the apical direction (i.e., along the axis of the spinal cord) or the medial-lateral direction (i.e., perpendicular to the axis of the spinal cord).

[0016] E-troll and navigation programming modes differ in part in how clinicians change electrode configurations from one to another. E-troll programming utilizes a technique called "panning," which cycles through a predefined electrode configuration along the electrode sequence without altering the basic form of the configuration. Navigation programming utilizes a technique called "weaving," which moves one or more anodes around the cathode while simultaneously moving the cathode slowly along the electrode sequence. E-troll and navigation programming modes can have different clinical uses (e.g., finding the "sweet spot" in panning or shaping an electric field around the cathode in weaving).

[0017] In a novel current-guiding method described in U.S. Patent Application Serial No. 12 / 938,282 entitled “System and Method for Mapping Arbitrary Electric Fields to Pre-existing Lead Electrodes” (which is explicitly stated by reference and is also herein), stimulation targets in the form of dummy poles (e.g., dummy bipolar or tripolar poles) are defined, and modulation parameters, including subdivided current values ​​on each electrode, are computationally determined in a manner simulating these dummy poles. It will be understood that current guidance can be achieved by moving the dummy poles around the lead, such that an appropriate subdivided current value for the electrode is calculated for each of the locations of the dummy poles. Therefore, current guidance can be achieved using any number and arrangement of electrodes, thereby solving the aforementioned problem.

[0018] A simplified virtual tripole can be used to determine a virtual bipolar or tripolar structure, consisting of a cathode and an upper (or head) anode and a lower (or tail) electrode positioned along the longitudinal axis from the cathode. The virtual tripole can be defined using three values: (1) the position of the cathode relative to the electrodes; (2) the focal length, which is the distance between the anode and the cathode; and (3) the percentage of current on the upper cathode. This technique is described in U.S. Provisional Patent Application Serial No. 61 / 452,965, entitled “Neurostimulation System for Defining a Generalized Virtual Multipole,” which is explicitly cited and is also incorporated herein by reference.

[0019] While patients typically tolerate substitute or artificial sensations relative to the pain sensation, they sometimes report these sensations as uncomfortable, and therefore, in some cases, they can be considered adverse side effects of neuromodulation therapy. Because the perception of paresthesia has been used as an indicator that the applied electrical energy actually alleviates the pain experienced by the patient, the amplitude of the applied electrical energy is usually tuned to the level that induces the paresthesia. Delivery of sub-threshold electrical energy (e.g., high-rate pulsed energy and / or low-pulse-width energy) can be effective in providing neuromodulation for chronic pain without inducing paresthesia.

[0020] However, due to the lack of sensory abnormalities, which could otherwise indicate that the activated electrodes are properly positioned relative to the target tissue location, it is difficult to immediately determine whether the delivered subthreshold neuromodulation therapy has been optimized in terms of providing effective treatment and minimizing energy consumption. Furthermore, if one or more implanted neuromodulation leads migrate relative to the target tissue location, subthreshold neuromodulation may exceed the effective treatment range (either if the coupling efficiency between one or more neuromodulation leads and the target tissue location decreases, resulting in a lack of effective treatment; or if the coupling efficiency between one or more neuromodulation leads and the target tissue location increases, resulting in a sensory abnormality or ineffective energy consumption).

[0021] Therefore, there is still a need for a neural modulation system that can compensate for the migration of one or more neural modulation leads during subthreshold neural modulation therapy.

[0022] Another issue is that patients receiving subthreshold therapy may not notice when the battery of the implanted neuromodulation device runs out, and because subthreshold therapy is not accompanied by sensory abnormalities, patients may not immediately realize that they are no longer receiving treatment. Therefore, it is still necessary to inform patients when the battery of the implanted neuromodulation device is almost depleted.

[0023] Traditional computerized programming systems typically have one or more programming modes designed to achieve a single therapeutic effect (e.g., superthreshold neuromodulation therapy (e.g., treatment accompanied by sensory abnormalities) or subthreshold neuromodulation therapy (e.g., treatment without sensory abnormalities)). To this end, a particular computer programming system typically restricts the modulation parameters that the neuromodulation device can be programmed with. For example, a computerized programming system designed for superthreshold neuromodulation may restrict the modulation parameters to those known to result in superthreshold neuromodulation therapy, while a computerized programming system designed for subthreshold neuromodulation may restrict the modulation parameters to those known to result in subthreshold neuromodulation therapy. There is no known computer programming system that, to the extent that a particular computer programming system has one or more programming modes capable of providing multiple therapeutic effects (e.g., both superthreshold and subthreshold neuromodulation therapy), transitions between multiple programming modes that have been optimized to separately achieve multiple therapeutic effects.

[0024] Therefore, there is still a need for a computer programming system that can switch between multiple programming modes designed to achieve different therapeutic outcomes, such as superthreshold therapy and subthreshold therapy.

[0025] Furthermore, while it is possible to program neural modulators using traditional computerized programming systems, with both overthreshold and subthreshold modulation programs, this requires extensive programming or reprogramming to fit the session and determine the optimal modulation program, typically requiring the presence of a clinician. Moreover, assuming the neural modulator and accompanying handheld external controls are programmed to selectively deliver overthreshold or subthreshold neural modulation therapy, the user may still need to navigate through a series of steps (e.g., via menus) to switch between the overthreshold and subthreshold modulation programs. Therefore, there remains a need to provide users with more efficient devices for switching between overthreshold and subthreshold modulation therapy.

[0026] Furthermore, while overthreshold and subthreshold neural modulation can provide different mechanisms for delivering treatment to a patient, under the assumption that the patient requires only one or the other of these treatments, neural modulation systems are typically programmed to utilize only one of these treatments at any given time. Therefore, the need for synergistic delivery of overthreshold and subthreshold modulated energy remains. Summary of the Invention

[0027] According to one aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array. The external control device includes a user interface comprising a programming selection control element configured to allow a user to select one of a first programming mode (e.g., a semi-automatic programming mode) having a first constraint on modulation parameters and a second programming mode (e.g., a semi-automatic programming mode) having a second constraint on modulation parameters different from the first constraint. In one embodiment, the modulation parameter is a pulse rate, in which case the first constraint may be, for example, an upper limit less than 1500 Hz, and the second constraint may be, for example, a lower limit greater than 1500 Hz. In another embodiment, the modulation parameter is a pulse width, in which case the first constraint may be, for example, a lower limit greater than 100 μs, and the second constraint may be, for example, an upper limit less than 100 μs. In another embodiment, the modulation parameter is an electrode combination (e.g., a subdivided electrode combination), in which case the first limitation may be, for example, a range of electrode combinations having only an anode electrode as a primary modulation electrode, and the second limitation may be, for example, a range of electrode combinations having only a cathode electrode as a primary modulation electrode, or the first limitation may be, for example, a range of unipolar electrode combinations, and the second limitation may be, for example, a range of multipolar electrode combinations.

[0028] The external control device also includes controller / processor circuitry configured to allow a user to program the neural modulator in a first programming mode and in a second programming mode in response to actuation of a programming selection control element. The external control device may also include telemetry circuitry, in which case the controller / processor is configured to program the neural modulator via the telemetry circuitry. The external control device may also include a housing containing the user interface and the controller / processor circuitry.

[0029] In one embodiment, the controller / processor circuitry is configured to define a virtual multipole relative to the electrode array and calculate the amplitude values ​​of the electrode array simulating the virtual multipole when programming the neural modulator in a first programming mode, wherein the first set of modulation parameters includes the calculated amplitude values. Each of the first and second programming modes can be a semi-automatic programming mode configured to obtain a virtual multipole on the electrode array.

[0030] In another embodiment, the controller / processor circuitry is configured to define a set of modulation parameters during programming of the neural modulator in a first programming mode, and to instruct the neural modulator to transfer electrical energy to the electrode array according to the set of modulation parameters in a manner that follows the trajectory of the electric field synthesized relative to the electrode array shift. In this case, in response to actuation of the programming selection control element, the controller / processor circuitry can be configured to obtain another set of modulation parameters from the last set of the set of modulation parameters, and to instruct the neural modulator to transfer electrical energy to the electrode array according to another set of modulation parameters during neural modulator-to-device programming in a second programming mode. The controller / processor circuitry can also be configured to obtain other sets of modulation parameters such that the electric field resulting from the transfer of electrical energy to the electrode array according to the other set of modulation parameters has a trajectory identical to the trajectory of the electric field resulting from the transfer of electrical energy to the electrode array according to the last set of modulation parameters.

[0031] According to a second aspect of the invention, a method is provided for an implantable neuromodulator operatively coupled to an electrode array implanted in adjacent tissue (e.g., spinal cord tissue) of a patient with a medical condition (e.g., chronic pain). The neuromodulator can be implanted within the patient. The method includes: delivering electrically modulated energy to the patient's tissue according to a set of modulation parameters, thereby progressively shifting the trajectory of a synthesized electric field relative to said tissue, such that multiple different trajectories of the synthesized electric field can be associated with the set of modulation parameters, respectively. The method further includes: causing the patient to perceive a sensory abnormality according to at least one of the modulation parameters in response to the delivery of the electrically modulated energy to the tissue; identifying one of the at least one set of modulation parameters based on the perceived sensory abnormality; and obtaining another set of modulation parameters from the identified set of modulation parameters.

[0032] In one method, the identified set of modulation parameters and other sets of modulation parameters define different electrode combinations. In this case, the identified set of modulation parameters may, for example, define a pulse rate less than 1500 Hz, and the other sets of modulation parameters may define a pulse rate greater than 1500 Hz. In another method, the identified set of modulation parameters and other sets of modulation parameters define different pulse widths. In this case, the identified set of modulation parameters may, for example, define a pulse width greater than 100 μs, and the other sets of modulation parameters may, for example, define a pulse width less than 100 μs. In yet another method, the identified set of modulation parameters and other sets of modulation parameters define different electrode combinations (e.g., different subdivided electrode combinations). In this case, the identified set of modulation parameters may, for example, be a unipolar electrode combination, and the other sets of modulation parameters may, for example, be a multipolar electrode combination.

[0033] The method further includes delivering electrically modulated energy to the patient's tissue according to another set of modulation parameters, thereby creating an electric field with a trajectory relative to the tissue without causing sensory abnormalities in the patient, the trajectory being identical to the trajectory of the electric field associated with the identified set of modulation parameters. The neural modulator can be programmed using other sets of modulation parameters. In one method, the medical condition affects a region of the patient's body, in which case the electrically modulated energy delivered to the tissue according to the identified set of modulation parameters could cause the patient to perceive sensory abnormalities in that region of the body.

[0034] The method may optionally include: (e.g., by selecting virtual poles on the electrode array) defining a series of virtual poles relative to the electrode array; calculating the amplitude values ​​of electrode combinations that are simulated for the series of virtual poles, such that a series of modulation parameter sets define the electrode combinations respectively; defining another virtual pole relative to the electrode array; and calculating the amplitude values ​​of another electrode combination that is simulated for other virtual poles, such that other modulation parameter sets define other electrode combinations.

[0035] According to a third aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array implanted within a patient. The external control device includes: a user interface including control elements; and telemetry circuitry configured to communicate with the neural modulator. The external control device further includes controller / processor circuitry configured to, in response to an event (a user actuation of a second control element on the user interface, a signal indicating migration of the implanted electrode array within the patient, or a time-occurring event), direct the neural modulator via the telemetry circuitry to deliver electrically modulated energy to the electrode array with incrementally increasing amplitude values. In another embodiment, the user interface includes a second control element, and the event is a user actuation of the second control element.

[0036] The controller / processor circuitry is also configured to automatically calculate a decreasing amplitude value as a function of an incrementing amplitude value in response to actuation of the control element, and to direct the neural modulator via telemetry circuitry to deliver electrically modulated energy to the electrode array at the calculated amplitude value (e.g., the last incrementing amplitude value). In one embodiment, the calculated function is a percentage of an incrementing amplitude value (e.g., in the range of 30% to 70%, and more specifically, in the range of 40% to 60%). In another embodiment, the calculated function is the difference between an incrementing amplitude value and a constant. The external control device may also include a housing containing the user interface, telemetry circuitry, and controller / processor circuitry. If the electrically modulated energy comprises an electrical pulse train, each of the incrementing amplitude value and the calculated amplitude value can be a pulse amplitude value.

[0037] According to a fourth aspect of the invention, a neural modulation system is provided. The neural modulation system includes: an electrode array; and an implantable neural modulator (which may be implantable) coupled to the electrode array. The neural modulation system further includes an external control device configured to, in response to an event (another user input, detection of migration of the electrode array relative to a patient, or a time-occurring event), instruct the neural modulator to deliver electrically modulated energy to the electrode array at incrementally increasing amplitude values, automatically calculate a decreasing amplitude value as a function of one of the incrementally increasing amplitude values ​​(e.g., the last incrementally increasing amplitude value), and instruct the neural modulator to deliver electrically modulated energy to the electrode array at the calculated amplitude value. In one embodiment, the calculated function is a percentage of an incrementally increasing amplitude value (e.g., in the range of 30% to 70%, and more specifically, in the range of 40% to 60%). In another embodiment, the calculated function is the difference between an incrementally increasing amplitude value and a constant. In an optional embodiment, the neural modulation system further includes a sensor configured to measure physiological parameters indicating superthreshold stimulation of neural tissue. If the electrical modulation energy includes an electrical pulse train, each of the incrementally increasing amplitude value and the calculated amplitude value can be a pulse amplitude value.

[0038] According to a fifth aspect of the invention, a method of providing treatment to a patient is provided. The method includes: delivering electrically modulated energy to a target tissue location of the patient at a programmed amplitude value, thereby providing treatment to the patient without the perception of sensory abnormalities. The method further includes: delivering electrically modulated energy to the patient at a series of progressively increasing amplitude values ​​relative to the programmed amplitude value until the patient perceives sensory abnormalities. If the patient experiences chronic pain in a body area, the patient may perceive sensory abnormalities in that body area.

[0039] The method further includes: automatically calculating a reduced amplitude value as a function of a series of incrementally increasing amplitude values ​​(e.g., the last incrementally increasing amplitude value), causing the patient to perceive a sensory abnormality, and delivering electrically modulated energy to a target tissue location of the patient at the calculated amplitude value, thereby providing treatment to the patient without the perception of a sensory abnormality. In one method, the calculated function is a percentage of an incrementally increasing amplitude value (e.g., in the range of 30% to 70%, and more specifically, in the range of 40% to 60%). In another method, the calculated function is the difference between an incrementally increasing amplitude value and a constant.

[0040] If the delivered electrically modulated energy comprises a train of electrical pulses, then each of the programmed amplitude value, the incrementally increasing amplitude value, and the calculated amplitude value can be a pulse amplitude value. In one method, electrically modulated energy is delivered from at least one electrode implanted in a patient to a target tissue location at programmed amplitude values, one or more electrodes migrate relative to the target tissue location as the electrically modulated energy is delivered to the target tissue location at programmed amplitude values, and a series of amplitude values ​​are generated after at least one electrode has migrated relative to the target tissue location.

[0041] According to a sixth aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array implanted in a patient. The neural modulator is configured to operate in a superthreshold delivery mode such that the neural modulator (e.g., with a pulse rate of less than 1500 Hz, and more specifically less than 500 Hz; or with a pulse width of greater than 100 μs, and more specifically greater than 200 μs) delivers electrically modulated energy configured to provide superthreshold therapeutic effects to the patient. In a subthreshold delivery mode, the neural modulator (e.g., with a pulse rate of less than 1500 Hz, and more specifically greater than 2500 Hz; or with a pulse width of less than 100 μs, and more specifically less than 50 μs) delivers electrically modulated energy configured to provide subthreshold therapeutic effects to the patient. The neural modulator may optionally be configured to operate in a hybrid delivery mode such that the neural modulator delivery is configured to provide electrically modulated energy for both superthreshold and subthreshold therapeutic effects to the patient.

[0042] The external control device includes: a user interface comprising control elements, telemetry circuitry configured to communicate with the neural modulator, and controller / processor circuitry configured to, in response to a single actuation of the control elements, direct the neural modulator via the telemetry circuitry to switch between an overthreshold delivery mode and a subthreshold delivery mode. If the neural modulator is configured to operate in a hybrid delivery mode, the controller / processor circuitry can also be configured to, in response to another single actuation of the control elements, direct the neural modulator via the telemetry circuitry to switch between one or both of the overthreshold delivery mode and the subthreshold delivery mode, and between the hybrid delivery mode. The external control device may also include a housing containing the user interface, the telemetry circuitry, and the controller / processor circuitry.

[0043] In one embodiment, the controller / processor circuitry is configured to direct the neural modulator to switch back and forth between a superthreshold delivery mode and a subthreshold delivery mode in response to a rotating actuation of a control element. In another embodiment, the controller / processor is configured to select between a pre-existing superthreshold modulation program and a pre-existing subthreshold modulation program in response to a single actuation of a control element, for directing the neural modulator to operate in a superthreshold delivery mode to deliver electrically modulated energy according to the superthreshold modulation program, and for directing the neural modulator to operate in a subthreshold delivery mode to deliver electrically modulated energy according to the subthreshold modulation program. In yet another embodiment, the controller / processor is configured to obtain a new modulation program from a pre-existing modulation program in response to a single actuation of a control element, for directing the neural modulator to operate in a superthreshold delivery mode to deliver electrically modulated energy according to one of the new modulation program and the pre-existing modulation program, and for directing the neural modulator to operate in a subthreshold delivery mode to deliver electrically modulated energy according to the other of the new modulation program and the pre-existing modulation program.

[0044] According to a seventh aspect of the invention, a neural modulation system is provided. The neural modulation system includes: an electrode array; and an implantable neural modulator coupled to the electrode array. The neural modulator is configured to be selectively positioned between a superthreshold delivery mode (e.g., delivering electrically modulated energy to the electrode array at a pulse rate less than 1500 Hz and more specifically, at a pulse rate less than 500 Hz; or at a pulse width greater than 100 μs and more specifically, at a pulse width greater than 200 μs) for providing superthreshold therapy to a patient, and a subthreshold delivery mode (e.g., delivering electrically modulated energy to the electrode array at a pulse rate less than 1500 Hz and more specifically, at a pulse rate greater than 2500 Hz; or at a pulse width less than 100 μs and more specifically, at a pulse width less than 50 μs) for providing subthreshold therapy to a patient. The neural modulator may optionally be configured to operate in a hybrid delivery mode, such that the neural modulator delivery is configured to provide electrically modulated energy for both superthreshold and subthreshold therapy to the patient.

[0045] The neural modulation system further includes an external control device configured to direct the neural modulator to switch between a superthreshold delivery mode and a subthreshold delivery mode in response to a single actuation of a control element. If the neural modulator is configured to operate in a hybrid delivery mode, the external control device may also be configured to direct the neural modulator to switch between one or both of the superthreshold delivery mode and the subthreshold delivery mode, and a hybrid delivery mode, in response to another single actuation of a control element.

[0046] In one embodiment, the external control device is configured to direct the neural modulator to switch back and forth between a superthreshold delivery mode and a subthreshold delivery mode in response to a rotating actuation of the control element. In another embodiment, the external control device is configured to select between a pre-existing superthreshold modulation program and a pre-existing subthreshold modulation program in response to a single actuation of the control element, for directing the neural modulator to operate in the superthreshold delivery mode to deliver electrically modulated energy according to the superthreshold modulation program, and for directing the neural modulator to operate in the subthreshold delivery mode to deliver electrically modulated energy according to the subthreshold modulation program. In yet another embodiment, the external control device is configured to obtain a new modulation program from a pre-existing modulation program in response to a single actuation of the control element, for directing the neural modulator to operate in the superthreshold delivery mode to deliver electrically modulated energy according to one of the new modulation program and the pre-existing modulation program, and for directing the neural modulator to operate in the subthreshold delivery mode to deliver electrically modulated energy according to the other of the new modulation program and the pre-existing modulation program.

[0047] According to an eighth aspect of the invention, a method of providing treatment to a patient using a patient-implanted neural modulator and an external control device is provided. The method includes: operating the neural modulator in one of a superthreshold delivery mode and a subthreshold delivery mode, and switching the operation of the neural modulator to the other of the superthreshold delivery mode and the subthreshold delivery mode. When in the superthreshold delivery mode for providing superthreshold treatment to the patient, the neural modulator delivers electrically modulated energy to the patient (e.g., with a pulse rate of less than 1500 Hz, and more specifically, with a pulse rate of less than 500 Hz; or with a pulse width of greater than 100 μs, and more specifically, with a pulse width of greater than 200 μs); and when in the subthreshold delivery mode for providing subthreshold treatment to the patient, the neural modulator delivers electrically modulated energy to the patient (e.g., with a pulse rate of less than 1500 Hz, and more specifically, with a pulse rate of greater than 2500 Hz; or with a pulse width of less than 100 μs, and more specifically, with a pulse width of less than 50 μs). If a patient experiences chronic pain in a body area, and when the neural modulator is in overthreshold delivery mode, the patient perceives sensory abnormalities in the body area when modulated energy is delivered to the patient, the method may optionally include switching the operation of the neural modulator to a hybrid delivery mode. In this case, when in a hybrid delivery mode providing both overthreshold and subthreshold therapy to the patient, the neural modulator delivers electrically modulated energy to the patient.

[0048] One method further includes switching the operation of the neural modulator back and forth between a superthreshold delivery mode and a subthreshold delivery mode. Another method further includes obtaining a new modulation program from a pre-existing modulation program, wherein, when in one of the superthreshold and subthreshold delivery modes, the neural modulator delivers electrically modulated energy to the patient according to the pre-existing modulation program, and when in the other of the superthreshold and subthreshold delivery modes, the neural modulator delivers electrically modulated energy to the patient according to the new modulation program.

[0049] According to a ninth aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array implanted in a patient. The external control device includes: a user interface configured to receive input from a user; telemetry circuitry configured to communicate with the neural modulator; and a controller / processor circuitry configured to obtain a new modulation program from a pre-existing modulation program in response to user input and to instruct the neural modulator to deliver modulated energy according to the new modulation program. The pre-existing modulation program is one of a superthreshold modulation program (e.g., with a pulse rate less than 1500 Hz, more specifically less than 500 Hz; or with a pulse width greater than 100 μs, more specifically greater than 200 μs) and a subthreshold modulation program (e.g., with a pulse rate less than 1500 Hz, more specifically greater than 2500 Hz; or with a pulse width less than 100 μs, more specifically less than 50 μs), and the new modulation program is the other of the superthreshold and subthreshold modulation programs. The external control device may further include a housing containing a user interface, telemetry circuitry, and controller / processor circuitry. In an alternative embodiment, the controller / processor is configured to obtain a new modulation program from a pre-existing modulation program in response to another user input and to instruct the neural modulator to deliver modulation energy according to the new modulation program. The new modulation program includes a hybrid modulation program.

[0050] In one embodiment, the controller / processor is configured to obtain a new modulation scheme from a pre-existing modulation scheme by calculating a pulse amplitude value as a function of the pulse amplitude value of the pre-existing modulation scheme, and to include the calculated pulse amplitude value in the new modulation scheme. The function of the pulse amplitude value can be a percentage of the pulse amplitude value. For example, if the new modulation scheme is a subthreshold modulation scheme, the percentage is in the range of 30% to 70%, and if the new modulation scheme is a superthreshold modulation scheme, the percentage is in the range of 150% to 300%. More specifically, if the new modulation scheme is a subthreshold modulation scheme, the percentage is in the range of 40% to 60%, and if the new modulation scheme is a superthreshold modulation scheme, the percentage is in the range of 175% to 250%. As another example, the function of the pulse amplitude value can be one of the difference between the pulse amplitude and a constant, or the sum between the pulse amplitude and the constant.

[0051] According to a tenth aspect of the invention, a neural modulation system is provided. The neural modulation system includes: an electrode array and an implantable neural modulator coupled to the electrode array. The neural modulator is configured to be selectively positioned between a superthreshold delivery mode (e.g., delivering electrically modulated energy to the electrode array at a pulse rate of less than 1500 Hz and more specifically at a pulse rate of less than 500 Hz; or at a pulse width of more than 100 μs and more specifically at a pulse width of more than 200 μs) for providing superthreshold therapy to a patient, and a subthreshold delivery mode (e.g., delivering electrically modulated energy to the electrode array at a pulse rate of less than 1500 Hz and more specifically at a pulse rate of more than 2500 Hz; or at a pulse width of less than 100 μs and more specifically at a pulse width of less than 50 μs) for providing subthreshold therapy to a patient.

[0052] The neural modulation system also includes an external control device configured to obtain a new modulation program from a pre-existing modulation program in response to user input and to instruct the neural modulator to deliver modulation energy according to the new modulation program. The pre-existing modulation program is one of a superthreshold modulation program and a subthreshold modulation program, and the new modulation program is the other of the superthreshold and subthreshold modulation programs. In an alternative embodiment, the external control device is configured to obtain another new modulation program from a pre-existing modulation program in response to another user input and to instruct the neural modulator to deliver modulation energy according to the other new modulation program. The other new modulation program includes a hybrid modulation program.

[0053] In one embodiment, the external control device is configured to obtain a new modulation program from a pre-existing modulation program by calculating a pulse amplitude value as a function of the pulse amplitude value of the pre-existing modulation program, and to include the calculated pulse amplitude value in the new modulation program. The function of the pulse amplitude value is a percentage of the pulse amplitude value. For example, if the new modulation program is a subthreshold modulation program, the percentage may be in the range of 30% to 70%, and if the new modulation program is a superthreshold modulation program, the percentage may be in the range of 150% to 300%. More specifically, if the new modulation program is a subthreshold modulation program, the percentage may be in the range of 40% to 60%, and if the new modulation program is a superthreshold modulation program, the percentage may be in the range of 175% to 250%. As another example, the function of the pulse amplitude value may be one of the difference between the pulse amplitude and a constant, or the sum between the pulse amplitude and the constant.

[0054] According to an eleventh aspect of the invention, a method of providing treatment to a patient is provided. The method includes: delivering modulated energy to the patient according to a pre-existing modulation program, thereby providing the patient with one of overthreshold treatment (e.g., with a pulse rate of less than 1500 Hz and more specifically, less than 500 Hz; or with a pulse width of greater than 100 μs and more specifically, greater than 200 μs) and subthreshold treatment (e.g., with a pulse rate of less than 1500 Hz and more specifically, greater than 2500 Hz; or with a pulse width of less than 100 μs and more specifically, less than 50 μs); obtaining a new modulation program from the pre-existing modulation program; and delivering modulated energy to the patient according to the new modulation program, thereby providing the patient with the other of the overthreshold treatment and subthreshold treatment. If the patient experiences chronic pain in a body area, the patient may perceive sensory abnormalities in the body area when modulated energy is delivered to the patient to provide overthreshold treatment. An alternative method includes: obtaining another new modulation program from the pre-existing modulation program and directing a neural modulator to deliver modulated energy according to the other new modulation program. This other new modulation program includes a hybrid modulation program.

[0055] In one method, a new modulation scheme is obtained from a pre-existing modulation scheme by calculating a pulse amplitude value as a function of the pulse amplitude value of the pre-existing modulation scheme, and the calculated pulse amplitude value is included in the new modulation scheme. The function of the pulse amplitude value can be a percentage of the pulse amplitude value. For example, if the new modulation scheme is a subthreshold modulation scheme, the percentage can be in the range of 30% to 70%, and if the new modulation scheme is a superthreshold modulation scheme, the percentage can be in the range of 150% to 300%. More specifically, if the new modulation scheme is a subthreshold modulation scheme, the percentage can be in the range of 40% to 60%, and if the new modulation scheme is a superthreshold modulation scheme, the percentage can be in the range of 175% to 250%. As another example, the function of the pulse amplitude value can be one of the difference between the pulse amplitude and a constant, or the sum between the pulse amplitude and the constant.

[0056] According to a twelfth aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array implanted in a patient. The external control device includes: a user interface, telemetry circuitry configured to communicate with the neural modulator, and a controller / processor circuitry configured to, in response to input to the user interface, instruct the neural modulator via the telemetry circuitry to deliver overthreshold electrical modulation energy according to a set of overthreshold modulation parameters (e.g., defining a pulse rate less than 1500 Hz and more specifically less than 500 Hz; or defining a pulse width greater than 100 μs and more specifically greater than 200 μs) and to deliver subthreshold electrical modulation energy according to a set of subthreshold modulation parameters (e.g., defining a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or defining a pulse width less than 100 μs and more specifically less than 50 μs). The overthreshold modulation program and the subthreshold modulation program are included in a hybrid modulation program. The overthreshold modulation parameter set may define a first amplitude value, and the subthreshold modulation parameter set may define a second amplitude value less than the first amplitude value. For example, the second amplitude value is in the range of 30% to 70% of the first amplitude value, and more specifically, in the range of 40% to 60% of the first amplitude value. The external control device may also include a housing containing a user interface, telemetry circuitry, and controller / processor circuitry.

[0057] In one embodiment, the controller / processor is configured to direct the neural modulator to simultaneously deliver overthreshold electrical modulation energy to a first set of electrodes and subthreshold electrical modulation energy to a second set of electrodes different from the first set of electrodes. In another embodiment, the controller / processor circuitry is configured to direct the neural modulator to simultaneously deliver overthreshold electrical modulation energy as an overthreshold electrical pulse train in a first timing channel and subthreshold electrical modulation energy as a subthreshold electrical pulse train in a second timing channel, such that the pulses of the corresponding electrical pulse trains do not overlap. In yet another embodiment, the controller / processor is configured to direct the neural modulator to alternately burst on and off overthreshold electrical modulation energy, and alternately burst on and off subthreshold electrical modulation energy, such that the bursts of overthreshold electrical modulation energy and the bursts of subthreshold electrical modulation energy are interleaved.

[0058] According to a thirteenth aspect of the invention, a neural modulation system includes: an electrode array, an implantable neural modulator coupled to the electrode array, and an external control device configured to instruct the neural modulator to deliver overthreshold electrical modulation energy according to a set of overthreshold modulation parameters (e.g., defining a pulse rate less than 1500 Hz and more specifically less than 500 Hz; or defining a pulse width greater than 100 μs and more specifically greater than 200 μs) and to deliver subthreshold electrical modulation energy according to a set of subthreshold modulation parameters (e.g., defining a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or defining a pulse width less than 100 μs and more specifically less than 50 μs). The overthreshold modulation parameter set and the subthreshold modulation parameter set are included in a hybrid modulation procedure. The overthreshold modulation parameter set may define a first amplitude value, and the subthreshold modulation parameter set may define a second amplitude value less than the first amplitude value. For example, the second amplitude value may be in the range of 30% to 70% of the first amplitude value, and more specifically, may be in the range of 40% to 60% of the first amplitude value.

[0059] In one embodiment, the external control device is configured to instruct the neural modulator to simultaneously deliver overthreshold electrical modulation energy to a first set of electrodes and subthreshold electrical modulation energy to a second set of electrodes different from the first set of electrodes. In another embodiment, the external control device is configured to instruct the neural modulator to simultaneously deliver overthreshold electrical modulation energy as an overthreshold electrical pulse train in a first timing channel and subthreshold electrical modulation energy as a subthreshold electrical pulse train in a second timing channel, such that the pulses of the corresponding electrical pulse trains do not overlap. In yet another embodiment, the external control device is configured to instruct the neural modulator to alternately burst on and off overthreshold electrical modulation energy, and alternately burst on and off subthreshold electrical modulation energy, such that the bursts of overthreshold electrical modulation energy and the bursts of subthreshold electrical modulation energy are interleaved.

[0060] According to a fourteenth aspect of the invention, a method of providing treatment to a patient is provided. The method includes: delivering superthreshold electrical modulation energy to the patient's tissue according to a superthreshold modulation parameter set, thereby providing the patient with superthreshold treatment (e.g., by defining a pulse rate less than 1500 Hz and more specifically less than 500 Hz; or defining a pulse width greater than 100 μs and more specifically greater than 200 μs); and delivering subthreshold electrical modulation energy to the patient's tissue according to a subthreshold modulation parameter set, thereby providing the patient with subthreshold treatment (e.g., by defining a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or defining a pulse width less than 100 μs and more specifically less than 50 μs). The superthreshold modulation parameter set and the subthreshold modulation parameter set are included in a hybrid modulation procedure. The superthreshold modulation parameter set may define a first amplitude value, and the subthreshold modulation parameter set may define a second amplitude value less than the first amplitude value. For example, the second amplitude value may be in the range of 30% to 70% of the first amplitude value, and more specifically, may be in the range of 40% to 60% of the first amplitude value. If a patient experiences chronic pain in a body area, the patient may perceive sensory abnormalities in the body area in response to the delivery of overthreshold modulated energy to the tissue, and the patient may not perceive sensory abnormalities in the body area in response to the delivery of subthreshold modulated energy to the tissue.

[0061] In one method, overthreshold electromodulation energy and subthreshold electromodulation energy are simultaneously delivered to a corresponding first electrode set and a second electrode set different from the first electrode set. In another method, overthreshold electromodulation energy and subthreshold electromodulation energy are simultaneously delivered in corresponding first and second timing channels, such that the pulses of the corresponding electrical pulse trains do not overlap. In yet another method, overthreshold electromodulation energy is alternately bursted on and off, and subthreshold electromodulation energy is alternately bursted on and off, such that the bursts of overthreshold electromodulation energy and the bursts of subthreshold electromodulation energy are interleaved.

[0062] According to a fifteenth aspect of the invention, an implantable, rechargeable neural modulator for use with a patient is provided. The neural modulator includes: a plurality of electrical terminals configured to be coupled to an electrode array; and a modulation output circuit coupled to the plurality of electrical terminals. The modulation output circuit is configured to selectively operate in a subthreshold delivery mode for delivering electrically modulated energy to the electrode array to provide subthreshold therapy to the patient and in a superthreshold delivery mode for delivering electrically modulated energy to the electrode array to provide superthreshold therapy to the patient.

[0063] The neural modulator also includes: a battery configured to store energy for the modulation output circuitry; a monitoring circuit configured to monitor the battery capacity level; and a controller / processor circuit configured to: operate the modulation output circuitry in a subthreshold delivery mode (e.g., by directing the modulation output circuitry to deliver electrically modulated energy at a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or by directing the modulation output circuitry to deliver electrically modulated energy at a pulse width less than 100 μs and more specifically less than 50 μs), compare the battery capacity level with a threshold (e.g., 50% or 25% of the total battery capacity), and if the battery capacity level is less than the threshold, switch the modulation output circuitry from the subthreshold delivery mode to a superthreshold delivery mode (e.g., by directing the modulation output circuitry to deliver electrically modulated energy at a pulse rate less than 1500 Hz and more specifically less than 500 Hz; or by directing the modulation output circuitry to deliver electrically modulated energy at a pulse width greater than 100 μs and more specifically greater than 200 μs).

[0064] In one embodiment, the controller / processor circuitry is configured to: instruct the modulation output circuitry to deliver electrically modulated energy at a first pulse amplitude value during a subthreshold delivery mode, and instruct the modulation output circuitry to deliver electrically modulated energy at a second pulse amplitude value greater than the first pulse amplitude value (e.g., within the range of 150% to 300% of the first pulse amplitude value, and more specifically within the range of 175% to 250% of the first pulse amplitude value) during a superthreshold delivery mode. In another embodiment, if the battery capacity level is not less than the threshold, the controller / processor is configured to instruct the modulation output circuitry to continue operating in the subthreshold delivery mode. The neural modulator may also include a housing comprising telemetry circuitry and the controller / processor circuitry.

[0065] According to a sixteenth aspect of the invention, a neural modulation system includes: an electrode array and an implantable rechargeable neural modulator coupled to the electrode array. The neural modulator is configured to operate in a subthreshold delivery mode (e.g., by delivering electrically modulated energy to the electrode array to provide subthreshold therapy to a patient via a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or by delivering electrically modulated energy with a pulse width less than 100 μs and more specifically less than 50 μs) and in a superthreshold delivery mode (e.g., by delivering electrically modulated energy to the electrode array to provide superthreshold therapy to a patient via a pulse rate less than 1500 Hz and more specifically less than 500 Hz; or by delivering electrically modulated energy with a pulse width greater than 100 μs and more specifically greater than 200 μs) for delivering electrically modulated energy to the electrode array to provide superthreshold therapy to a patient via a pulse rate greater than 1500 Hz and more specifically less than 500 Hz; or by delivering electrically modulated energy with a pulse width greater than 100 μs and more specifically greater than 200 μs).

[0066] The neural modulation system also includes controller / processor circuitry configured to: instruct the neural modulator to operate in a subthreshold delivery mode, compare a battery capacity level with a threshold (e.g., 50% or 25% of the full battery capacity), and instruct the neural modulator to switch from the subthreshold delivery mode to a superthreshold delivery mode if the battery capacity level is less than the threshold.

[0067] In one embodiment, the controller / processor circuitry is configured to: instruct the neural modulator to deliver electrically modulated energy at a first pulse amplitude value during a subthreshold delivery mode, and instruct the neural modulator to deliver electrically modulated energy at a second pulse amplitude value greater than the first pulse amplitude value (e.g., within the range of 150% to 300% of the first pulse amplitude value, and more specifically within the range of 175% to 250% of the first pulse amplitude value) during a superthreshold delivery mode. In another embodiment, if the battery capacity level is not less than the threshold, the controller / processor is configured to instruct the neural modulator to continue operating in the subthreshold delivery mode.

[0068] According to a seventeenth aspect of the invention, a method of providing treatment to a patient using a rechargeable neural modulator implanted in the patient is provided. The method includes: delivering subthreshold electrical modulated energy from the neural modulator to the patient's tissue, thereby providing subthreshold treatment to the patient, for example by delivering electrically modulated energy at a pulse rate greater than 1500 Hz and more specifically greater than 2500 Hz; or by delivering a pulse width less than 100 μs and more specifically less than 50 μs; measuring the battery capacity level of the neural modulator; and comparing the measured battery capacity level with a threshold (e.g., 50% or 25% of the full battery capacity).

[0069] The method further includes: delivering overthreshold electrical modulation energy from the neural modulator to the tissue if the battery capacity level is less than the threshold, thereby providing overthreshold therapy to the patient, and recharging the neural modulator in response to the delivery of overthreshold electrical modulation energy (e.g., by delivering electrical modulation energy at a pulse rate of less than 1500 Hz and more specifically less than 500 Hz; or by delivering electrical modulation energy at a pulse width of greater than 100 μs and more specifically greater than 200 μs) from the neural modulator to the tissue. If the patient experiences chronic pain in a body area, the patient may perceive sensory abnormalities in the body area in response to the delivery of overthreshold modulation energy to the tissue, and the patient may not perceive sensory abnormalities in the body area in response to the delivery of subthreshold modulation energy to the tissue.

[0070] In one method, subthreshold electrical modulation energy is delivered at a first pulse amplitude value, and overthreshold electrical modulation energy is delivered at a second pulse amplitude value greater than the first pulse amplitude value (e.g., within the range of 150% to 300% of the first pulse amplitude value, and more specifically within the range of 175% to 250% of the first pulse amplitude value).

[0071] According to an eighteenth aspect of the invention, an external control device is provided for programming an implantable neural modulator coupled to an electrode array implanted in a patient. The external control device includes: a user interface including control elements; and telemetry circuitry configured to communicate with the neural modulator. The external control device further includes: a controller / processor circuitry configured to direct the neural modulator via the telemetry circuitry to deliver superthreshold electrical modulation energy to the electrode array according to a superthreshold modulation parameter set and to deliver subthreshold electrical modulation energy to the electrode array according to a subthreshold modulation parameter set. The superthreshold modulation parameter set and the subthreshold modulation parameter set are included in a hybrid modulation program.

[0072] The controller / processor circuitry is also configured to automatically direct a neural modulator via telemetry circuitry to deliver electrically modulated energy to the electrode array at progressively increasing amplitude values ​​in response to events such as user actuation of a second control element on the user interface, signals indicating migration of the implanted electrode array within the patient, or time-occurring events. In one embodiment, the user interface includes a second control element, and the event is user actuation of the second control element.

[0073] The controller / processor is also configured to automatically calculate a decreased amplitude value as a function of an incrementally increasing amplitude value (e.g., the last incrementally increasing amplitude value) in response to actuation of the control element, and to direct the neural modulator via telemetry circuitry to deliver electrically modulated energy to the electrode array at the calculated amplitude value. In one embodiment, the calculated function is a percentage of an incrementally increasing amplitude value (e.g., in the range of 30% to 70%, and more specifically in the range of 40% to 60%). In another embodiment, the calculated function is the difference between an incrementally increasing amplitude value and a constant.

[0074] In one embodiment, the controller / processor is configured to instruct the neural modulator via telemetry circuitry to restart the delivery of overthreshold electrical modulation energy to the electrode array based on a set of overthreshold modulation parameters. The set of overthreshold modulation parameters with calculated amplitude values ​​and the set of subthreshold modulation parameters are included in the new hybrid modulation procedure.

[0075] In another embodiment, the user interface is further configured to receive user input when the patient perceives a sensory abnormality in response to the delivery of subthreshold electromodulated energy with incrementally adjusted amplitude values. In this case, the controller / processing circuitry is configured to select one of the incrementally adjusted amplitude values ​​as the perception threshold based on the received user input. In yet another embodiment, the neural modulator is further configured to sense at least one evoked compound action potential (eCAP) in a neuronal population at a target tissue location in response to the delivery of subthreshold electromodulated energy with incrementally adjusted amplitude values. In this case, the controller / processing circuitry is configured to select one of the incrementally adjusted amplitude values ​​as the perception threshold based on at least one sensed eCAP.

[0076] The external control device may further include a housing containing a user interface, telemetry circuitry, and controller / processor circuitry. If the electrical modulation energy comprises an electrical pulse train, each of the incrementally increasing amplitude value and the calculated amplitude value can be a pulse amplitude value.

[0077] According to a nineteenth aspect of the present invention, a neural modulation system is provided. The neural modulation system includes: an electrode array; and an implantable neural modulator (which may be implantable) coupled to the electrode array. The neural modulation system further includes an external control device configured to: instruct the neural modulator to deliver superthreshold electrical modulation energy to the electrode array according to a superthreshold modulation parameter set, and to deliver subthreshold electrical modulation energy to the electrode array according to a subthreshold modulation parameter set. The superthreshold modulation parameter set and the subthreshold modulation parameter set are included in a hybrid modulation procedure.

[0078] The external control device is also configured to, in response to an event (e.g., another user input, a signal indicating migration of the implanted electrode array in the patient, or a time-occurring event), direct the neural modulator to deliver subthreshold electrically modulated energy to the electrode array with incrementally increasing amplitude values, automatically calculate a decreasing amplitude value as a function of one of the incrementally increasing amplitude values ​​(e.g., the last incrementally increasing amplitude value), and direct the neural modulator to deliver electrically modulated energy to the electrode array with the calculated amplitude value. In one embodiment, the calculated function is a percentage of an incrementally increasing amplitude value (e.g., in the range of 30% to 70%, and more specifically, in the range of 40% to 60%). In another embodiment, the calculated function is the difference between an incrementally increasing amplitude value and a constant. If the electrically modulated energy comprises a train of electrical pulses, each of the incrementally increasing amplitude value and the calculated amplitude value can be a pulse amplitude value.

[0079] In one embodiment, the external control device is further configured to receive user input when the patient perceives a sensory abnormality in response to the delivery of subthreshold electrically modulated energy with incrementally adjusted amplitude values, and to select one of the incrementally adjusted amplitude values ​​as a perception threshold based on the received user input. In another embodiment, the neural modulation system further includes a monitoring circuit configured to sense at least one evoked compound action potential (eCAP) in a neuronal population at a target tissue location in response to the delivery of subthreshold electrically modulated energy with incrementally adjusted amplitude values. In this case, the external control device may be configured to select one of the incrementally adjusted amplitude values ​​as a perception threshold based on at least one sensed eCAP.

[0080] According to a twentieth aspect of the invention, a method for providing treatment to a patient is provided. The method includes: delivering superthreshold electrical modulation energy to the patient's tissue according to a superthreshold modulation parameter set, thereby providing superthreshold treatment to the patient; and delivering subthreshold electrical modulation energy to the patient's tissue according to a subthreshold modulation parameter set, thereby providing subthreshold treatment to the patient. The superthreshold modulation parameter set and the subthreshold modulation parameter set are included in a hybrid modulation procedure. The method further includes: automatically stopping the delivery of superthreshold electrical modulation energy to the tissue in response to an event.

[0081] The method further includes delivering electrically modulated energy to the patient at a series of incrementally increasing amplitude values ​​relative to a programmed amplitude value until the patient perceives sensory abnormalities. If the patient experiences chronic pain in a body area, the patient may perceive sensory abnormalities in that body area.

[0082] The method further includes: automatically calculating a reduced amplitude value as a function of one of a series of incrementally increasing amplitude values ​​(e.g., the last incrementally increasing amplitude value), based on the delivered electrical modulation causing the patient to perceive a sensory abnormality, and delivering electrically modulated energy to a target tissue location of the patient at the calculated amplitude value, thereby providing treatment to the patient without the perception of a sensory abnormality. In one method, the calculated function is a percentage of an incrementally increasing amplitude value (e.g., in the range of 30% to 70%, and more specifically in the range of 40% to 60%). In another method, the calculated function is the difference between an incrementally increasing amplitude value and a constant.

[0083] If the delivered electrically modulated energy comprises an electrical pulse train, each of the programmed amplitude value, the incrementally increasing amplitude value, and the calculated amplitude value can be a pulse amplitude value. One method further includes restarting the delivery of superthreshold electrically modulated energy to the tissue based on a set of superthreshold modulation parameters. The set of superthreshold modulation parameters and the set of subthreshold modulation parameters with calculated amplitude values ​​are included in the new hybrid modulation procedure. Another method further includes sensing at least one evoked compound action potential (eCAP) in a neuronal population at the target tissue location in response to a subthreshold electrical pulse train delivered with incrementally adjusted amplitude values. One of the incrementally adjusted amplitude values ​​is selected as the sensing threshold based on one or more sensed eCAPs. In another method, electrically modulated energy is delivered from at least one electrode implanted in the patient to the target tissue location with a programmed amplitude value, one or more electrodes migrating relative to the target tissue location as the electrically modulated energy is delivered with the programmed amplitude value, and a series of amplitude values ​​is generated after the at least one electrode has migrated relative to the target tissue location. Attached Figure Description

[0084] The accompanying drawings illustrate the design and practicality of preferred embodiments of the invention, wherein similar elements are indicated by common reference numerals. To better understand how the above and other advantages and objects of the invention are obtained, a more particular description of the invention, briefly described above, will be provided with reference to specific embodiments thereof, which are illustrated in the accompanying drawings. It is to be understood that these drawings depict only exemplary embodiments of the invention and are therefore not intended to limit its scope, and that the invention will be described and explained using additional specificity and detail through the use of the drawings, wherein:

[0085] Figure 1 This is a plan view of a spinal cord modulation (SCM) system constructed according to an embodiment of the present invention;

[0086] Figure 2 It is for use with patients. Figure 1 A floor plan of the SCM system;

[0087] Figure 3 yes Figure 1 Cross-sectional views of the implantable pulse generator (IPG) and percutaneous leads used in the SCM system;

[0088] Figure 4 This is a diagram of single-phase cathode electrical modulation energy;

[0089] Figure 5a It is a diagram of biphase electrical modulation energy with cathode modulation pulse and active charge recovery pulse;

[0090] Figure 5b It is a diagram of biphase electrical modulation energy with cathode modulation pulse and passive charge recovery pulse;

[0091] Figure 6a It is by Figure 3 Timing diagram of the subthreshold pulse train delivered by the IPG to the electrode;

[0092] Figure 6b It is by Figure 3 Timing diagram of the overthreshold pulse train delivered by the IPG to the electrode;

[0093] Figure 6c It is by Figure 3 Timing diagrams of subthreshold and overthreshold pulse trains delivered by IPG to different electrodes;

[0094] Figure 6d During the two timing channels, by Figure 3 Timing diagrams of IPG delivery to two different electrodes for subthreshold and overthreshold pulse trains;

[0095] Figure 6e It is by Figure 3 Timing diagram of IPG delivery to pulse trains with alternating overthreshold bursts and subthreshold bursts;

[0096] Figure 6f During the two timing channels, by Figure 3 Timing diagrams of bursts of overthreshold pulses and bursts of subthreshold pulses delivered by IPG;

[0097] Figure 7 It is a reminder to the user to recharge the IPG. Figure 3 A flowchart of a method executed by IPG;

[0098] Figure 8 yes Figure 1 A front view of the remote control (RC) used in the SCM system;

[0099] Figure 9 yes Figure 8 A block diagram of the internal components of the RC;

[0100] Figure 10 It shows the calibration by Figure 3 IPG provides subthreshold therapy, by Figure 8 A flowchart of a method executed by the RC;

[0101] Figure 11 yes Figure 1 A block diagram of the internal components of the clinician programmer (CP) used in the SCM system;

[0102] Figure 12 It is used for manual programming mode. Figure 3 Programming with IPG Figure 11 A floor plan of the CP's user interface;

[0103] Figure 13 It is used for electronic drag-and-drop programming mode. Figure 3 Programming with IPG Figure 11 A floor plan of the CP's user interface;

[0104] Figure 14 It is used for navigation programming mode Figure 3 Programming with IPG Figure 11 A floor plan of the CP's user interface;

[0105] Figure 15 It is used to detect and switch to programming mode. Figure 3 Programming with IPG Figure 11 A floor plan of the CP's user interface;

[0106] Figure 16 It is used for subthreshold to programming mode Figure 3 Programming with IPG Figure 11 A floor plan of the CP's user interface;

[0107] Figure 17 It specifically showcases the advanced table's extension to resolution and focus control. Figure 13 A floor plan of the user interface; and

[0108] Figure 18 It is for use Figure 11 CP to match Figure 3 The flowchart shows the steps involved in programming an IPG to provide subthreshold therapy to patients to treat chronic pain. Detailed Implementation

[0109] The following description relates to a spinal cord modulation (SCM) system. However, it is to be understood that while the invention is well-suited for application in SCM, it may not be limited thereto in its broadest aspects. Rather, the invention can be used with any type of implantable circuitry for stimulating tissue. For example, the invention can be used as part of a pacemaker, defibrillator, cochlear stimulator, retinal stimulator, stimulator configured to produce coordinated limb movements, cortical stimulator, deep brain stimulator, peripheral nerve stimulator, microstimulator, or any other neurostimulator configured to treat urinary incontinence, sleep apnea, shoulder subluxation, headache, etc.

[0110] First turn Figure 1An exemplary SCM system 10 typically includes multiple (in this case, two) implantable neural modulation leads 12, an implantable pulse generator (IPG) 14, an external remote controller RC 16, a clinician programmer (CP) 18, an external test modulator (ETM) 20, and an external charger 22.

[0111] The IPG 14 is physically connected to a modulation lead 12 via one or more percutaneous lead extensions 24, the modulation lead 12 having a plurality of electrodes 26 arranged in an array. In the illustrated embodiment, the modulation lead 12 is a percutaneous lead, and for this purpose, the electrodes 26 may be arranged coaxially along the modulation lead 12. While any suitable number of neural modulation leads 12 may be provided, including only one, the illustrated number of neural modulation leads 12 is two. Alternatively, surgical paddle leads may be used to replace one or more of the percutaneous leads. As will be described in more detail below, the IPG 14 includes a pulse generation circuit that delivers electrically modulated energy to the electrode array 26 in the form of a pulsed electrical waveform (i.e., a time-series electrical pulse) according to a set of modulation parameters.

[0112] ETM 20 can also be physically connected to the neural modulation lead 12 via percutaneous lead extension 28 and external cable 30. Having a pulse generation circuit similar to that of IPG 14, ETM 20 also delivers electrically modulated energy to electrode array 26 in the form of pulsed electrical waveforms according to a set of modulation parameters. The main difference between ETM 20 and IPG 14 is that ETM 20 is a non-implantable device, used experimentally after implantation of the neural modulation lead 12 and before implantation of IPG 14 to test the responsiveness of the modulation to be provided. Therefore, any functionality described herein with respect to IPG 14 can be performed similarly with respect to ETM 20. For simplicity, details of ETM 20 are not described herein. Details of exemplary embodiments of the ETM are disclosed in U.S. Patent No. 6,895,280, which is expressly incorporated herein by reference.

[0113] RC 16 can be used to remotely control ETM 20 via bidirectional RF communication link 32. Once IPG 14 and neural modulation lead 12 are implanted, RC 16 can be used to remotely control IPG 14 via bidirectional RF communication link 34. This control allows IPG 14 to be turned on or off and programmed with different sets of modulation parameters. IPG 14 is also operable to modify programmed modulation parameters to actively control the characteristics of the electrically modulated energy output by IPG 14. As will be described in more detail below, CP 18 provides clinicians with detailed modulation parameters for programming IPG 14 and ETM 20 in the operating room and subsequent sessions.

[0114] CP 18 can perform this function by indirectly communicating with IPG 14 or ETM 20 via RC 16 through IR communication link 36. Alternatively, CP 18 can communicate directly with IPG 14 or ETM 20 via RF communication link (not shown). The detailed modulation parameters provided by CP 18 for clinicians are also used to program RC 16, allowing subsequent modifications to the modulation parameters through operation of RC 16 in stand-alone mode (i.e., without the assistance of CP 18).

[0115] External charger 22 is a portable device for percutaneous charging of IPG 14 via inductive link 38. Once IPG 14 is programmed and its power is charged by external charger 22 or otherwise recharged, IPG 14 can function as a programmable device without the presence of RC 16 or CP 18. For simplicity, details of external charger 22 will not be described herein. Details of exemplary embodiments of the external charger are disclosed in U.S. Patent No. 6,895,280, which is expressly incorporated herein by reference.

[0116] like Figure 2 As shown, a neural modulation lead 12 is implanted in the spine 42 of patient 40. The preferred placement of the neural modulation lead 12 is proximal, i.e., docked near or above the area of ​​the spinal cord to be modulated. Due to a lack of space near the exit point of the neural modulation lead 12 from the spine 42, the IPG 14 is typically implanted in a surgical stoma bag in the abdomen or above the hip. Of course, the IPG 14 can also be implanted in other locations on the patient's body. The lead extension 24 helps to position the IPG 14 away from the exit point of the electrode lead 12. As shown, the CP 18 communicates with the IPG 14 via the RC 16.

[0117] Now refer to Figure 3 The external characteristics of the neural modulation leads 12 and IPG 14 will be briefly described below. One of the neural modulation leads 12a has eight electrodes 26 (labeled E1 to E8), and another neural modulation lead 12b has eight electrodes 26 (labeled E9 to E16). Of course, the actual number and shape of the leads and electrodes will vary depending on the intended application. The IPG 14 includes a housing 44 (described in more detail below) for housing electronics and other components, and a connector 46 to which the proximal end of the neural modulation lead 12 is fitted in a manner that electrically couples the electrodes 26 to the electronics within the housing 44. The housing 44 is made of a conductive biocompatible material such as titanium and forms a sealed compartment to protect the internal electronics from damage by human tissue and fluids. In some cases, the housing 44 can also function as an electrode.

[0118] IPG 14 includes electronic components such as a controller / processor (e.g., a microprocessor) 39, a memory 41, a battery 43, telemetry circuitry 45, a monitoring circuitry 47, a modulation output circuitry 49, and other suitable components known to those skilled in the art. The microcontroller 39 executes a suitable program stored in the memory 41 to guide and control neural modulation performed by IPG 14. Telemetry circuitry 45, including an antenna (not shown), is configured to receive programming data (e.g., operating procedures and / or modulation parameters) from RC 16 and / or CP 18 in a suitably modulated carrier signal, and this programming data is then stored in the memory (not shown). Telemetry circuitry 45 is also configured to transmit status data to RC 16 and / or CP 18 in a suitably modulated carrier signal. The battery 43, which can be a rechargeable lithium-ion or lithium-ion polymer battery, provides operating power to IPG 14. Monitoring circuitry 47 is configured to monitor the current capacity level of battery 43.

[0119] The modulation output circuit 49 provides electrical modulation energy to the electrodes 26 in the form of pulsed electrical waveforms via electrical terminals (not shown) according to a set of modulation parameters programmed into the IPG 14. These modulation parameters may include electrode combinations defining which electrodes are activated as anodes (positive), cathodes (negative), and off (zero), the percentage of modulation energy allocated to each electrode (a subdivided (i.e., divided into several parts) electrode configuration), and electrical pulse parameters defining the pulse amplitude (in milliamperes or volts depending on whether the IPG 14 supplies a constant current or a constant voltage to the electrode array 26), pulse width (in microseconds), pulse rate (in pulses per second), and burst rate (measured in modulation on duration X and modulation off duration Y).

[0120] Electrical modulation occurs between two (or more) activated electrodes, one of which may be the IPG shell 44. Modulated energy can be delivered to the tissue via unipolar or multipolar (e.g., bipolar, tripolar, etc.) methods. Unipolar modulation occurs when one of the selected lead electrodes 26, along with the shell 44 of the IPG 14, is activated, thereby transferring modulated energy between the selected electrode 26 and the shell. Bipolar modulation occurs when two of the lead electrodes 26 are activated as an anode and a cathode, thereby transferring modulated energy between the selected electrodes 26. For example, electrode E3 on the first lead 12a can be activated as an anode, while electrode E11 on the second lead 12b is activated as a cathode. Tripolar modulation occurs when three of the lead electrodes 26 are activated, with two as anodes and the remaining one as a cathode, or two as cathodes and the remaining one as an anode. For example, electrodes E4 and E5 on the first lead 12a can be activated as anodes, while electrode E12 on the second lead 12b is activated as a cathode.

[0121] Any one of electrodes E1-E16 and the shell electrode can be assigned to up to k possible groups or timing "channels". In one embodiment, k can be equal to 4. The timing channels identify which electrodes are simultaneously pulling or sinking current to create an electric field in the tissue to be modulated. The amplitude and polarity of the electrodes on the channels can vary. Specifically, the electrodes can be selected as positive (pull current), negative (tube current), or off (zero current) polarity in any of the k timing channels.

[0122] Modulated energy can be delivered as single-phase or multi-phase electrical energy between designated electrode groups. For example... Figure 4 As shown, single-phase electrical energy is represented as a series of electrical pulses, which consists entirely of negative pulses (anode) or, alternatively, entirely of positive pulses (anode).

[0123] Multiphase electrical energy consists of a series of alternating positive and negative pulses. For example, such as... Figure 5a and Figure 5b As shown, multiphase electrical energy can include a series of biphase pulses, each comprising a cathode (negative) modulation pulse phase and an anode (positive) charge recovery pulse phase. The charge recovery pulse phase is generated after the modulation phase to prevent DC charge migration through the tissue, thereby avoiding electrode degradation and cell damage. That is, during the modulation period (the length of the modulation phase), charge is transferred across the electrode-tissue interface via current at the electrode, and subsequently pulled back away from the electrode-tissue interface during the recharge period (the length of the charge recovery phase) via current of opposite polarity at the same electrode.

[0124] The second phase can be an active charge recovery phase. Figure 5a In the active charge recovery phase, current is actively transmitted through the electrodes via a current source or voltage source, or the second phase can be a passive charge recovery phase. Figure 5b In the passive charge recovery phase, current is passively transferred through the electrodes via the redistribution of charge flowing from the coupling capacitance present in the circuit. In contrast to passive recharging, active recharging allows for faster charging while avoiding other potential charge imbalances. Another electrical pulse parameter, in the form of an intermediate phase, can define the time interval between pulses of the biphase pulse (measured in microseconds). Although Figure 5a and Figure 5b The modulation phase and charge recovery phase of the biphasic pulse shown are cathode and anode, respectively. However, it should be understood that the modulation pulse and charge recovery pulse of the biphasic pulse may be anode and cathode, respectively, depending on the desired therapeutic outcome.

[0125] In the illustrated embodiment, the IPG 14 can individually control the amplitude of the current flowing through each electrode. In this case, a current generator is preferred, wherein individually current-regulated amplitudes from independent current sources can be selectively generated for each electrode. While this system best utilizes the invention, other neural modulators that can be used with the invention include neural modulators with voltage-regulated outputs. While individually programmable electrode amplitudes are optimal for fine control, a single output source that is switched across electrodes can also be used, although it offers less fine-tuning for programming. Hybrid current and voltage regulation devices can also be used with the invention. Further details discussing the detailed structure and function of the IPG are described more fully in U.S. Patent Nos. 6,516,227 and 6,993,384, which are expressly incorporated herein by reference.

[0126] It should be noted that, instead of IPG, the SCS system 10 can alternatively utilize an implantable receiver-modulator (not shown) connected to the neural modulation lead 12. In this case, the power source for powering the implanted receiver, such as a battery, and the control circuitry for commanding the receiver stimulator are contained in an external controller inductively coupled to the receiver-modulator via an electromagnetic link. Data / power signals are percutaneously coupled from a transmission coil connected to a cable placed on the implanted receiver-modulator. The implanted receiver-modulator receives the signals and generates modulation according to the control signals.

[0127] More obviously in this invention, IPG 14 can operate in over-threshold delivery mode, subthreshold delivery mode and hybrid delivery mode.

[0128] In overthreshold delivery mode, IPG 14 is configured to deliver electrically modulated energy to the patient to provide overthreshold therapy (in which case, the patient experiences sensory abnormalities). For example, as Figure 6a As shown, exemplary overthreshold pulse trains can be delivered with relatively high pulse amplitude (e.g., 5 mA), relatively low pulse rate (e.g., less than 1500 Hz, preferably less than 500 Hz), and relatively high pulse width (e.g., greater than 100 μs, preferably greater than 200 μs). Although the overthreshold pulse train is shown as a single-phase cathode pulse train, it should be understood that the overthreshold pulse train is preferably biphase.

[0129] In subthreshold delivery mode, IPG 14 is configured to deliver electrically modulated energy to the patient to provide subthreshold therapy (in which case, no sensory abnormalities are caused by the patient). For example, as Figure 6bAs shown, exemplary subthreshold pulse trains can be delivered with relatively low pulse amplitude (e.g., 2.5 mA), relatively high pulse rate (e.g., greater than 1500 Hz, preferably greater than 2500 Hz), and relatively low pulse width (e.g., less than 100 μs, preferably less than 50 μs). Although the subthreshold pulse train is shown as a single-phase cathode pulse train, it should be understood that the subthreshold pulse train is preferably biphase with active charge recovery pulses, as described in further detail below.

[0130] In hybrid delivery mode, IPG 14 is configured to deliver electrically modulated energy to the patient, providing both overthreshold and subthreshold therapeutic effects. In one embodiment, the overthreshold and subthreshold modulated energy are delivered simultaneously to different electrode sets within a single timing channel. Preferably, the different electrode sets do not share a common electrode, thus eliminating conflicts between different energies. For example, as... Figure 6c As shown, an exemplary overthreshold pulse train can be delivered to electrode E1, while an exemplary subthreshold pulse train can be delivered to electrode E2. Because the overthreshold and subthreshold pulse trains are delivered to different electrodes, the pulses of the corresponding pulse trains can overlap in a timely manner.

[0131] In another embodiment, overthreshold modulation energy and subthreshold therapy are simultaneously delivered to a common electrode set within a corresponding timing channel to be combined into a modulation program. For example, as... Figure 6d As shown, an exemplary overthreshold pulse train can be delivered to electrode E1 in timing channel A (coverage area A) and a subthreshold pulse train can be delivered to electrode E1 in timing channel B (coverage area B), such that the pulses of the corresponding overthreshold pulse train and subthreshold pulse train are interleaved without temporary overlap.

[0132] In yet another embodiment, the overthreshold modulation energy and the subthreshold modulation energy can be burst-on and burst-off in a single timing channel or multiple timing channels, respectively. For example, as Figure 6e As shown, the exemplary overthreshold pulse train can repeatedly burst open and close, wherein when the overthreshold pulse train bursts close, the exemplary subthreshold pulse train bursts open, and when the overthreshold pulse train bursts open, the exemplary subthreshold pulse train bursts close. Therefore, the overthreshold pulse train and the subthreshold pulse train will burst open and close alternately (i.e., the overthreshold pulse train will burst open and then close, and the subthreshold pulse train will burst open and then close). Alternatively, the exemplary overthreshold pulse train can repeatedly burst open and close in a first timing channel A (coverage area A), and the exemplary overthreshold pulse train can repeatedly burst open and close in a second timing channel B (coverage area B), such that the alternating overthreshold pulse train and subthreshold pulse train produce the following... Figure 6f As shown. In any case, the bursts of overthreshold pulse trains and the bursts of subthreshold pulse trains will interleave with each other.

[0133] In any case, the delivery of modulated energy during hybrid delivery modes leverages the advantages of both overthreshold and subthreshold therapy. For example, because they rely on different pain relief mechanisms, the delivery of both overthreshold and subthreshold modulated energy to the same common area of ​​the patient can provide more effective treatment than either one could accomplish alone.

[0134] Also, for some of the more obvious aspects of this invention, assuming the IPG 14 is currently operating in subthreshold delivery mode, it notifies the patient approximately when the battery capacity level of the IPG 14 will be depleted. Specifically, the microcontroller 39 is configured to compare the battery capacity level obtained from the monitoring circuit 47 with a previously stored threshold in the memory 41, and if the battery capacity level is less than the threshold, to switch the modulation output circuit 49 from subthreshold delivery mode to overthreshold delivery mode (or alternatively, a hybrid delivery mode), thereby notifying the user to recharge the IPG 14.

[0135] As an example, the threshold could be 50% of the total capacity of battery 43. As another example, the threshold could be 25% of the total capacity of battery 43. Ultimately, the value of this threshold will be chosen to balance providing maximum usage from the battery before recharging and allowing the user sufficient time to recharge IPG 14 before completely depleting the battery. Microcontroller 39 is configured to automatically switch the modulation output circuit 49 from subthreshold mode to overthreshold delivery mode (or alternatively, a hybrid delivery mode) after determining that the battery capacity level is below the threshold. When the battery capacity level is not below the threshold, microcontroller 39 is configured to maintain the modulation output circuit 49 in subthreshold delivery mode.

[0136] It should be understood that although IPG 14 is described as a means of performing control and processing functions to notify the user that it needs to be recharged, the control and processing functions can be implemented in an external control device (e.g., RC 16) that can place the IPG between over-threshold delivery mode, sub-threshold delivery mode and mixed threshold mode, as described in more detail below.

[0137] Now refer to Figure 7The method for notifying the user to recharge the IPG 14 will be described. First, the IPG 14 delivers subthreshold electrically modulated energy to an electrode array 26 implanted within the spinal cord tissue, thereby providing subthreshold therapy to the patient (step 200). In this instance, in response to the delivery of subpixel-modulated energy to the electrode array 26, the patient does not perceive any sensory abnormalities in the body area corresponding to pain. Next, the battery capacity level of the IPG 14 is measured (step 202), and the battery capacity level of the IPG 14 is compared to a predetermined threshold (204). If the battery capacity level is not less than the threshold, the IPG 14 continues to deliver subthreshold electrically modulated energy to the electrodes 26, thereby maintaining subthreshold therapy to the patient (step 200). If the battery capacity level is less than the threshold, superthreshold electrically modulated energy is delivered from the IPG 14 to the spinal cord tissue, thereby providing superthreshold therapy to the patient (step 206). In this instance, in response to the delivery of subthreshold modulated energy to the electrode array 26, the patient will perceive a sensory abnormality in the body area corresponding to the pain, thereby notifying the patient that the IPG 14 needs recharging. The external charger 22 is then used to routinely recharge the IPG 14 (step 208).

[0138] Now refer to Figure 8 An exemplary embodiment of RC 16 will now be described. As discussed previously, RC 16 is capable of communicating with IPG 14, CP 18, or ETS 20. RC 16 includes a housing 50 housing internal components (including a printed circuit board (PCB)) and a bright display screen 52 and a button pad 54 carried on the exterior of the housing 50. In the illustrated embodiment, the display screen 52 is a bright flat panel display, and the button pad 54 includes a diaphragm switch with a metal spring located above a flexible circuit and a keyboard connector directly connected to the PCB. In an alternative embodiment, the display screen 52 has touchscreen capability. The button pad 54 includes a plurality of buttons 56, 58, 60, and 62, which allow IPG 14 to be turned on and off, thereby allowing adjustment or setting of modulation parameters and selection between screens within IPG 14.

[0139] In the illustrated embodiment, button 56 functions as an on / off button that can be actuated to turn IPG 14 on and off. Button 58 functions as a selection button that allows RC 16 to switch between on-screen displays and / or parameters. Buttons 60 and 62 function as up / down buttons that can be actuated to increase or decrease any parameter in the pulse modulation parameters generated by IPG 14, including pulse amplitude, pulse width, and pulse rate. For example, selection button 58 can be actuated to place RC 16 in "pulse amplitude adjustment mode" while pulse amplitude can be adjusted via up / down buttons 60, 62, RC 16 in "pulse width adjustment mode" while pulse width can be adjusted via up / down buttons 60, 62, and RC 16 in "pulse rate adjustment mode" while pulse rate can be adjusted via up / down buttons 60, 62. Alternatively, dedicated up / down buttons 60, 62 can be provided for each modulation parameter. In addition to using the up / down button 60, any other type of actuator, such as a dial, slider, or button, can be used to increase or decrease the modulation parameters.

[0140] Reference Figure 9 The internal components of an exemplary RC 16 will now be described. The RC 16 typically includes a processor 64 (e.g., a microcontroller), a memory 66 storing operating programs to be executed by the controller / processor 64, and a set of modulation parameters; input / output circuitry, particularly telemetry circuitry 68, for outputting modulation parameters to the IPG 14 or otherwise directing the IPG 14 to deliver modulation energy based on the modulation parameters and receiving status information from the IPG 14; and input / output circuitry 70 for receiving modulation control signals from a button pad 54 or other control element and outputting them to a display screen 52 (e.g., a microcontroller). Figure 8 (As shown) Transmits status information. Further details of the function and internal components of the RC 16 are disclosed in U.S. Patent No. 6,895,280, which is incorporated herein by reference.

[0141] More obviously for the present invention, to allow the user to easily and quickly select between different modes, RC 16 includes a modulation selection control element 65, which in the illustrated embodiment takes the form of a button. The modulation selection control element 65 can be repeatedly actuated to switch the IPG 14 between an overthreshold delivery mode, a subthreshold delivery mode, and a hybrid delivery mode. For example, the modulation selection control element 65 can be actuated once to switch the IPG 14 from the overthreshold delivery mode to the subthreshold delivery mode, actuated again to deliver the IPG 14 from the subthreshold delivery mode to the hybrid delivery mode, actuated again to switch the IPG 14 from the hybrid delivery mode back to the overthreshold delivery mode, and so on. Of course, the order of mode selection can be changed. For example, the modulation selection control element 65 can be actuated once to deliver the IPG 14 from the subthreshold delivery mode to the overthreshold delivery mode, actuated again to deliver the IPG 14 from the overthreshold delivery mode to the hybrid delivery mode, actuated again to switch the IPG 14 from the hybrid delivery mode back to the subthreshold delivery mode, and so on. In any case, each of the modulation delivery modes can be selected by switching the modulation selection control element 65.

[0142] When operated in different delivery modes, the different modulation programs utilized by IPG 14 can be generated in any of a variety of ways. For example, if IPG 14 and / or RC 16 are pre-programmed via CP 18 (described in more detail below) using pre-existing overthreshold modulation programs, pre-existing subthreshold modulation programs, and pre-existing hybrid modulation programs, RC 16 selects only one of these pre-existing modulation programs in response to actuation of modulation selection control element 65. In this case, RC 16 can identify which pre-existing modulation program corresponds to the corresponding overthreshold, subthreshold, and hybrid program based on the characteristics of one or more sets of adjustment parameters defined by these programs, or when using CP 18 to generate these modulation programs, the user can identify and label each pre-existing modulation program as an overthreshold, subthreshold, or hybrid modulation program.

[0143] If a pre-existing modulation program does not exist for one or more of the over-threshold delivery mode, subthreshold delivery mode, and mixed delivery mode, RC 16 may generate a new modulation program based on one or more pre-existing modulation programs in response to the actuation of modulation selection control element 65 or different control elements.

[0144] In the presence of only a superthreshold modulation program, the RC 16 can quickly obtain a subthreshold modulation program from a pre-existing superthreshold modulation program. Specifically, the RC 16 can replace one or more of the electrical pulse parameter values ​​(pulse amplitude, pulse rate, pulse width) of the pre-existing superthreshold modulation program with electrical pulse parameter values ​​consistent with subthreshold therapy. For example, the RC 16 can calculate a new pulse amplitude value as a function of the superthreshold pulse amplitude value. The calculated function can be, for example, a percentage of the superthreshold pulse amplitude value (preferably in the range of 30% to 70%, and more preferably in the range of 40% to 60%) or the difference between the superthreshold pulse amplitude value and a constant (e.g., 1 mA). The RC 16 can select a relatively high pulse rate value (e.g., greater than 1500 Hz) as the new pulse rate value and / or select a relatively low pulse width value (e.g., less than 100 μs) for the new subthreshold modulation program. RC 16 can also calculate new subdivided electrode combinations based on pre-existing subthreshold modulation procedures (e.g., by switching from anode modulation to cathode modulation or vice versa, or from unipolar modulation to multipolar modulation or vice versa). However, the trajectory of the electric field resulting from delivering modulation energy according to the pre-existing subthreshold procedure should be maintained within the new subthreshold modulation procedure. This can be achieved using dummy target poles, as described in more detail below with reference to CP 18.

[0145] In the presence of only a subthreshold modulation program, the RC 16 can quickly obtain a subthreshold modulation program from a pre-existing one. Specifically, the RC 16 can replace one or more of the electrical pulse parameter values ​​(pulse amplitude, pulse rate, pulse width) of the pre-existing subthreshold modulation program with electrical pulse parameter values ​​consistent with superthreshold therapy. For example, the RC 16 can calculate a new pulse amplitude value as a function of the superthreshold pulse amplitude value. The calculated function can be, for example, a percentage of the subthreshold pulse amplitude value (preferably in the range of 150% to 300%, and more preferably in the range of 175% to 250%) or a sum of the subthreshold pulse amplitude value and a constant (e.g., 1 mA). The RC 16 can select a relatively low pulse rate value (e.g., less than 1500 Hz) as the new pulse rate value and / or select a relatively high pulse width value (e.g., greater than 100 μs) for the new subthreshold modulation program. RC 16 can also calculate new subdivided electrode combinations based on pre-existing subthreshold modulation procedures (e.g., by switching from anode modulation to cathode modulation or vice versa, or from unipolar modulation to multipolar modulation or vice versa). However, the trajectory of the electric field resulting from delivering modulation energy according to the pre-existing subthreshold procedure should be maintained in the new overthreshold modulation procedure. This can be achieved using dummy target poles, as described in more detail below with reference to CP 18.

[0146] When only a hybrid modulation program exists, RC 16 can simply copy the modulation parameters of the overthreshold component of the hybrid modulation program to a new overthreshold modulation program (to the extent required), and / or copy the modulation parameters of the subthreshold component of the hybrid modulation program to a new subthreshold modulation program (to the extent required). When both an overthreshold and a subthreshold program exist, RC 16 can combine the modulation parameters of these programs together to define a new hybrid modulation program (to the extent required). Alternatively, if only one of the overthreshold and subthreshold modulation programs exists, it can be combined with a modulation program obtained from the other of the overthreshold and subthreshold modulation programs to form a new hybrid modulation program.

[0147] Furthermore, for some notable aspects of this invention, in response to specific events, assuming that IPG 14 is currently programmed to deliver subthreshold treatment to the patient (e.g., a subthreshold modulation procedure or a hybrid modulation procedure), calibration of subpixel treatment (which may be out of treatment range due to the migration of one or more modulation leads 12 relative to the target tissue location in the patient) is initiated. The migration of one or more modulation leads 12 can inform the coupling efficiency between one or more modulation leads 12 and the target tissue location. Decreased coupling efficiency can cause subthreshold treatment to fall below the treatment range and result in ineffective treatment, while increased coupling efficiency can cause subthreshold treatment to exceed the treatment range and result in sensory abnormalities or other ineffective energy consumption. Specific events triggering the calibration of subthreshold treatment can be user-actuated control elements placed on RC 16 (one of the buttons on buttonpad 54 or a dedicated button), sensor signals indicating the migration of one or more neural modulation leads 12 relative to the target location in the patient, or time-occurring events, such as the elapsed time from a previous calibration procedure, such as the time of day, the number of days of the week, etc.

[0148] Once the subthreshold calibration is initialized, RC 16 is configured to direct IPG 14 to deliver modulation energy to electrode 26 at incrementally increasing amplitude values ​​(e.g., in 0.1 mA steps). RC 16 can be configured to automatically and incrementally increase the amplitude of the electrical pulse train delivered by IPG 14 without further user intervention, or it can be configured to incrementally increase the amplitude of the electrical pulse train delivered by IPG 14 each time a user actuates a control element, such as the up button 60. Preferably, other modulation parameters, such as electrode combination, pulse rate, and pulse width, are not changed during the incremental amplitude increase. Therefore, the only modulation parameter of the changed subthreshold modulation procedure is the pulse amplitude.

[0149] RC 16 is configured to prompt the user to actuate a control element, such as a designated button on button pad 54 or another dedicated button (not shown), via display 52 or a speaker (not shown), once the patient perceives a sensory abnormality. In response to this user input, RC 16 is configured to automatically calculate the reduced amplitude value as a function of the last incrementally increasing amplitude value that caused the patient to perceive the sensory abnormality, and modify the subthreshold modulation program stored in IPG 14 such that the modulated energy is delivered to electrode 26 according to the modified modulation program at the calculated amplitude value. Alternatively, instead of relying on user input, RC 16 can be configured to automatically calculate the reduced amplitude value in response to sensed physiological parameters indicating transthreshold stimulation of neural tissue (as a result of the delivery of modulated energy, evoked compound action potential (eCAP) sensed by IPG 14 at one or more electrodes 26). Further details relating to CAP are disclosed in U.S. Provisional Patent Application Serial No. 61 / 768,295 entitled “Neurostimulation system and method for automatically adjusting stimulation and reducing energy requirements using evoked action potential,” which is expressly incorporated herein by reference.

[0150] In any case, the function of the final incremental amplitude value is designed to ensure that the modulated energy subsequently delivered to the patient with the calculated amplitude value falls within the subthreshold therapeutic range. For example, the calculated function can be a percentage of the final incremental amplitude value (preferably in the range of 30% to 70%, and more preferably in the range of 40% to 60%). As another example, the calculated function can be the difference between the final incremental amplitude value and a constant (e.g., 1 mA).

[0151] It should be understood that if the calibration is initialized while the IPG 14 is operating in mixed delivery mode such that the delivered electrical modulation energy includes both one or more overthreshold electrical pulse trains and one or more subthreshold electrical pulse trains, then the one or more overthreshold electrical pulse trains are automatically temporarily paused so that calibration is performed only based on the remaining subthreshold electrical pulse trains. For example, refer back to Figure 6c The hybrid delivery mode shown in the figure stops the delivery of overthreshold pulse trains to electrode E1 during initial calibration, and subthreshold pulse trains are delivered to electrode E2 with increasing amplitude values ​​until a sensing threshold is determined and the reduced amplitude is calculated as the subthreshold amplitude value based on the sensing threshold, as described above.

[0152] In another example, go back to refer Figure 6dDuring initial calibration, the delivery of overthreshold pulse trains to electrode E1 is stopped, and the subthreshold pulse trains delivered to electrode E1 are used to continue the calibration process. (Refer to...) Figure 6e During initial calibration, the over-threshold bursts shown are stopped, so that calibration processing continues only based on sub-threshold bursts of the hybrid modulation procedure. (See reference...) Figure 6f When initializing calibration, the over-threshold pulse train of the timing channel is stopped, so that calibration processing continues only based on the sub-threshold pulse train of timing channel B.

[0153] Once the calibration process is complete and the subthreshold amplitude is calculated, as discussed above, the hybrid delivery mode is restarted, so that electrical energy is delivered based on both the original overthreshold pulse train and the subthreshold pulse train with the calibrated subthreshold amplitude.

[0154] It should also be understood that, in a preferred embodiment, RC 16 can be configured to store the calculated subthreshold amplitude generated from each calibration process. This is important because it provides the user with a crucial metric related to subthreshold treatment, allowing the user to more intelligently modify the modulation parameters of the subthreshold pulse train in later programming sessions.

[0155] Now refer to Figure 10 A method for calibrating subthreshold therapy using RC 16 will now be described. First, RC 16 is operated to direct IPG 14 to deliver electrically modulated energy to the patient's target tissue location according to a subthreshold modulation program stored within IPG 14, thereby providing therapy to the patient without the perception of sensory abnormalities (step 220). Then, a calibration trigger event occurs (step 222). This trigger input can be user input, a detected migration of one or more modulated leads relative to the target tissue location, or a time-occurring event. Next, it is determined whether the patient perceives sensory abnormalities in the pain area as a result of the delivery of modulated energy according to the unmodified subthreshold modulation program (step 204).

[0156] If the patient is not currently experiencing sensory abnormalities in the pain area at step 204, RC 16 increases the programmed amplitude value in increments and instructs IPG 14 to deliver electrically modulated energy to the patient at the increased amplitude value (step 226). Next, it is determined whether the patient is experiencing sensory abnormalities in the pain area as a result of the delivery of modulated energy at the increased amplitude value (step 228). If the patient is not experiencing sensory abnormalities in the pain area at step 228, RC 16 returns to step 226 to again increase the programmed amplitude value in increments and instructs IPG 14 to deliver electrically modulated energy to the patient at the increased amplitude value.

[0157] If the patient experiences paresthesia in the pain area at step 224 or 228, RC 16 calculates a reduced amplitude value as a function of the last incrementally increased amplitude value, at which the delivered electrical modulation causes the patient to experience paresthesia in the pain area (step 230). This calculation can be performed in response to user input or alternatively by sensing physiological parameters indicating that the patient is experiencing paresthesia. As described above, this function can be, for example, a percentage of the last incrementally increased amplitude value or the difference between the last incrementally increased amplitude value and a constant. RC 16 then uses the calculated amplitude value to modify the subthreshold modulation procedure (step 232) and returns to step 220 to direct IPG 14 to deliver electrically modulated energy to the patient's target tissue location according to the modified subthreshold modulation procedure, thereby providing treatment to the patient without the experience of paresthesia.

[0158] Therefore, it is understood that the subthreshold calibration technique ensures that any intended subthreshold treatment remains within an effective and energy-efficient treatment window, which may otherwise fall outside this window due to environmental changes such as lead migration or even postural changes or patient activity. While the subthreshold calibration technique has been described in relation to treatment of chronic pain, it should be understood that this calibration technique can be used to calibrate any subthreshold treatment provided to a patient with any disorder (where the perception of sensory abnormalities can be represented as an effective treatment for that disorder). Furthermore, although the subthreshold calibration technique is described as being performed in RC 16, it should be understood that the technique can be performed in CP 18 or even IPG 14. If performed by IPG 14, any user input necessary for implementing the subthreshold calibration technique can be transmitted from RC 16 to IPG 14 via telemetry circuit 68. In cases where user input is not required, such as if overthreshold stimulation is detected at one or more of electrodes 26 in place of patient feedback of sensory abnormalities, IPG 14 can perform the subthreshold calibration technique without any communication with RC 16.

[0159] As briefly discussed above, CP 18 greatly simplifies the programming of multiple electrode combinations, allowing users (e.g., physicians or clinicians) to easily determine the desired modulation parameters to be programmed into IPG 14 and RC 16. Therefore, modifications to the modulation parameters in the programmable memory of IPG 14 after implantation are performed by the user using CP 18, which can communicate directly with IPG 14 or indirectly via RC 16. In other words, CP 18 can be used by the user to modify the operating parameters of the electrode array 26 near the spinal cord.

[0160] like Figure 2As shown, the overall appearance of CP 18 can be that of a laptop personal computer (PC), and indeed, a PC can be implanted, suitably configured to include a directional programming device and programmed to perform the functions described herein. Alternatively, CP 18 can take the form of a microcomputer, a personal digital assistant (PDA), or even a remote control (RC) device with extended capabilities. Therefore, the programming method can be executed by executing software instructions contained within CP 18. Alternatively, this programming method can be executed using firmware or hardware. In any case, CP 18 can actively control the characteristics of the electrical stimulation generated by IPG 14 to allow determining optimal modulation parameters based on patient feedback, and to subsequently program IPG 14 using the optimal modulation parameters.

[0161] To allow users to perform these functions, CP 18 includes user input devices (such as a mouse 72 and a keyboard 74) and a programmable display screen 76 housed in a housing 78. It should be understood that other directional programming devices, such as a trackball, touchpad, or joystick, or directional buttons that are part of the keys associated with the keyboard 74, may be used in addition to or in place of the mouse 72.

[0162] In the illustrated embodiment described below, the display screen 76 takes the form of a conventional screen. In this case, a virtual pointing device, such as a cursor controlled by a mouse, joystick, trackball, etc., can be used to manipulate graphic targets on the display screen 76. In an alternative embodiment, the display screen 76 takes the form of a passive or active digitizer touchscreen. If the display screen is passive, the display screen 76 includes detection circuitry (not shown) that recognizes changes in pressure or current when a passive device, such as a finger or non-electronic stylus, touches the display screen. If the display screen is active, the display screen 76 includes detection circuitry that recognizes signals transmitted by an electronic pen or electronic stylus. In either case, the detection circuitry is capable of detecting when a physical pointing device (e.g., a finger, non-electronic stylus, or electronic stylus) approaches the display screen closely, whether it makes physical contact between the pointing device and the display screen, or brings the pointing device close to the display screen to a predetermined distance, and detecting the position of the display screen where the physical pointing device is approaching closely. When the pointing device touches or otherwise approaches the display screen, the graphic target on the display screen adjacent to the touch point is "locked" for manipulation, and the previously locked target is unlocked when the pointing device moves away from the display screen. Further details regarding the use of a digital converter screen for programming are given in U.S. Provisional Patent Application Serial No. 61 / 561,760 entitled “Technique for Linking Electrodes Together during Programming of Neurostimulation System”.

[0163] like Figure 11 As shown, CP 18 includes a controller / processor 80 (e.g., a central processing unit (CPU)) and a memory 82 storing a modulation programming package 84, which can be executed by the controller / processor 80 to allow the user to program IPG 14 and RC 16. CP 18 also includes an output circuit 86 for downloading modulation parameters to IPG 14 and RC 16 and for uploading modulation parameters already stored in the memory 66 of RC 16 or the memory of IPG 14. Furthermore, CP 18 includes a user input device 88 (e.g., a mouse 72 or a keyboard 74) to provide user commands. Specifically, although the controller / processor 80... Figure 11 While shown as a single device, the processing and control functions can be executed by a single controller and processor. Therefore, it is understood that the control functions performed by CP 18 as described below can be executed by the controller, and the processing functions performed by CP 18 as described below can be executed by the processor.

[0164] The controller / processor 80 provides numerous displays (not shown) for the execution of the programming package 84, which can be navigated via the use of a mouse 72. These displays allow clinicians to select or enter patient profile information (e.g., name, date of birth, patient identification number, physician, diagnosis, and address), input program information (e.g., programming / tracking, implantation attempt system, implantation of IPG, implantation of IPG and one or more leads, replacement of IPG, replacement of IPG and multiple leads, replacement or modification of leads, explants, etc.), generate a patient pain map, define lead configuration and orientation, initialize and control the electrical modulation energy output from the neuromodulation lead 12, and select and program the IPG 14 using modulation parameters in surgical and clinical settings. Further details discussing the aforementioned CP functionality are disclosed in U.S. Patent Publication Serial No. 12 / 501,282 entitled "System and Method for Converting Tissue Stimulation Programs in a Format Usable by an Electrical Current Steering Navigator" and U.S. Patent Application Serial No. 12 / 614,942 entitled "System and Method for Determining Appropriate Steering Tables for Distributing Modulation energy Among Multiple Neuromodulation Electrodes," which are expressly incorporated herein by reference. The execution of programming package 84 provides a user interface that conveniently allows users to program IPG 14.

[0165] First refer to Figure 12 A graphical user interface (GUI) 100, which may be generated by CP 18, will be described to allow a user to program IPG 14. In the illustrated embodiment, GUI 100 includes three panels: a program selection panel 102, a conductor display panel 104, and a modulation parameter adjustment panel 106. Some embodiments of GUI 100 may allow one or both of the conductor display panel 102 and the parameter adjustment panel 106 to be closed and expanded by clicking on tab 108 (to show or hide the parameter adjustment panel 106) or clicking on tab 110 (to show or hide a full view of both the conductor selection panel 104 and the parameter adjustment panel 106).

[0166] The program selection panel 102 provides information related to the modulation program and coverage area (which is or can be defined for IPG 14). Specifically, the program selection panel 102 includes a disk 112 on which multiple modulation programs 114 (up to sixteen in this case) can be displayed and selected. The program selection panel 102 also includes a selected program status field 116, which indicates the number of modulation programs 114 currently selected (any number from “1” to “16”). In the illustrated embodiment, program 1 is the only one currently selected, as indicated by the number “1” in field 116. The program selection panel 102 also includes a name field 118 where the user can associate a unique name with the currently selected modulation program 114. In the illustrated embodiment, the currently selected program 1 is referred to as “lower back,” thereby identifying program 1 as a modulation program 114 designed to provide treatment for lower back pain.

[0167] The program selection panel 102 also includes multiple coverage areas 120 (up to four in this case), each of which can be associated with a set of modulation parameters to create the currently selected modulation program 114 (program 1 in this case). Each defined coverage area 120 includes a designation field 122 (one of the letters “A” through “D”) and an electrical pulse parameter field 124, which displays the electrical pulse parameters (specifically, pulse amplitude, pulse width, and pulse rate) of the modulation parameter set associated with that coverage area. In this example, only coverage area A is specified for program 1, as indicated by “A” in the designation field 122. The electrical pulse parameter field 124 indicates that a pulse amplitude of 5 mA, a pulse width of 210 μs, and a pulse rate of 40 Hz have been associated with coverage area A.

[0168] Each of the defined coverage areas 120 also includes a selection icon 126, which can be actuated in turn to activate or deactivate the corresponding coverage area 120. When a coverage area is activated, an electrical pulse train is delivered from IPG 14 to electrode array 26 according to the modulation parameter set associated with that coverage area. In particular, multiple coverage areas 120 can be activated simultaneously by actuating the selection icon 126 for the corresponding coverage area. In this case, multiple electrical pulse trains are delivered simultaneously from IPG 14 to electrode array 26 in an interleaved manner during the timing channel according to the corresponding modulation parameter set associated with the coverage area 120. Thus, each coverage area 120 corresponds to a timing channel.

[0169] To the extent that any of the remaining coverage areas 120 are undefined (in this case, three coverage areas are undefined), they include the text "Click to add another program area," indicating that any of these remaining coverage areas 120 can be selected for association with a set of modulation parameters. Once selected, the coverage area 120 is filled with the designation field 122, the electrical pulse parameter field 124, and the selection icon 126.

[0170] The lead display panel 104 includes graphic leads 128, which are shown with eight graphic electrodes 130 (electrodes E1-E8 for the first lead 128 and electrodes E9-E16 for the second lead 128). The lead display panel 104 also includes a graphic housing 132 representing a housing 44 for IPG 14. The lead display panel 104 also includes lead group selection tabs 134 (in this case, four), any one of which can be actuated to select one of four groups of graphic leads 128. In this case, the first lead group selection tab 134 is actuated, thereby displaying two graphic leads 128 in their defined orientations. In the case of additional leads 12 implanted in the patient, they can be associated with the additional lead group.

[0171] The parameter adjustment panel 106 also includes pulse amplitude adjustment control 136 (in milliamperes (mA), pulse width adjustment control 138 (in microseconds (μs), and pulse rate adjustment control 140 (in hertz (Hz),) which are displayed and actuated in all programming modes. Each of controls 136-140 includes a first arrow that can be actuated to decrease the corresponding modulation parameter value and a second arrow that can be actuated to increase the corresponding modulation parameter value. Each of controls 136-140 also includes a display area for displaying the currently selected parameter. In response to any adjustment of the electrical pulse parameters made by manipulation via the graphical controls in the parameter adjustment panel 106, the controller / processor 80 generates a corresponding set of modulation parameters (with a new pulse amplitude, a new pulse width, or a new pulse rate) and transmits this set of modulation parameters to the IPG 14 via the telemetry circuit 86 for use in delivering modulated energy to the electrode 26.

[0172] The parameter adjustment panel 106 includes a drop-down programming mode field 142, which allows the user to switch between manual programming mode, electronic trolling programming mode, navigation programming mode, probe programming mode, and subthreshold programming mode. Each of these programming modes allows the user to define the set of modulation parameters for the currently selected coverage area 120 for the currently selected program 114 via the graphical controls in the parameter adjustment panel 106 and the manipulation of the various graphical controls described below. In the illustrated embodiment, when switching between programming modes via actuation of the programming mode field 142, the last electrode configuration used to program the IPG 14 in the previous programming mode is converted to another electrode configuration used as the first electrode configuration to program the IPG 14 in the subsequent programming mode.

[0173] The electronic drag programming mode and navigation programming mode are designed to allow users to determine one or more effective sets of modulation parameters for providing overthreshold therapy to a patient, while the probe programming mode and subthreshold programming mode are designed to allow users to determine one or more effective sets of modulation parameters for providing subthreshold therapy to a patient. Specifically, the electronic drag programming mode is designed to rapidly scan the electrode array using a limited number of electrode configurations to gradually guide the electric field relative to the modulation leads until the target modulation location is located. Using the electrode configuration determined during the electronic drag programming mode as a starting point, the navigation programming mode is designed to shape the electric field using a large number of electrode configurations, thereby fine-tuning and optimizing the modulation coverage for patient comfort. Both the electronic drag programming mode and the navigation programming mode rely on immediate feedback from the patient in response to sensory abnormalities relative to the area of ​​the body in which the patient experiences pain. Like the electronic drag programming mode, the probe programming mode is designed to rapidly scan the electrode array using a limited number of electrode configurations to gradually guide the electric field relative to the modulation leads until the target modulation location is located. Like electronic drag programming, probe programming relies on immediate feedback from the patient in response to sensory abnormalities relative to the area of ​​the body in which the patient experiences pain. However, unlike electronic drag programming, navigation programming, and probe programming, subthreshold programming cannot rely on immediate feedback from the patient due to the lack of sensory abnormalities experienced by the patient during subthreshold modulation. Instead, subthreshold programming uses a shift in electrode configuration determined during probe programming to provide effective subthreshold modulation to the patient's identified target location.

[0174] like Figure 12As shown, the manual programming mode has been selected. In manual programming mode, each electrode 130 and the graphic housing 132 in the graphic lead 128 can be selected individually, allowing clinicians to use graphic controls located in the amplitude / polarity area 144 of the parameter adjustment panel 106 to set the amplitude (percentage) and polarity (cathode or anode) of the current allocated to that electrode 130, 132.

[0175] Specifically, the graphic polarity control 146 placed in the amplitude / polarity area 144 includes a "+" icon, a "-" icon, and an "off" icon, which can be actuated to switch the selected electrodes 130, 132 between a positive polarity (anode), a negative polarity (cathode), and an off state, respectively. The amplitude control 148 in the amplitude / polarity area 144 includes arrows that can be actuated to decrease the magnitude of the subdivided current of the selected electrodes 130, 132, and arrows that can be actuated to increase the magnitude of the subdivided current of the selected electrodes 130, 132. The amplitude control 148 also includes a display area indicating the adjustment magnitude of the subdivided current of the selected electrode 134. If the electrode is not seen and selected in the wire display panel 104, the amplitude control 148 is preferably disabled. In response to the adjustment of the subdivided electrode combination manipulated via the graphical control in the amplitude / polarity region 144, the controller / processor 80 generates a corresponding set of modulation parameters (with the new subdivided electrode combination) and transmits the set of modulation parameters to the IPG 14 via the telemetry circuit 86 for use in delivering modulated energy to the patient 26.

[0176] In the illustrated embodiment, electrode E2 is selected as the cathode to which 100% of the cathode current is allocated, and electrodes E1 and E3 are selected as the anodes to which 25% and 75% of the anode current, respectively, are allocated. Electrode E15 is shown as being selected to allow the user to subsequently allocate polarity and subdivided current to electrode E15 via graphical controls positioned in amplitude / polarity region 144. While graphical controls positioned in amplitude / polarity region 14 can be manipulated for any of the electrodes, dedicated graphical controls for selecting polarity and subdivided current values ​​can be associated with each electrode, as described in U.S. Patent Publication No. 2012 / 0290041 entitled “Neurostimulation System with On-Effector Programmer Control,” which is expressly incorporated herein by reference.

[0177] When manual programming mode is selected, parameter adjustment panel 106 also includes equalization control 150, which can be actuated to automatically equalize current distribution to all electrodes of the polarity selected by the corresponding "Anode +" and "Cathode -" icons. Unlike other programming modes described in more detail below, the range of pulse rate and pulse width of the modulation parameter set defined during manual programming mode is not limited to those known for causing only one of overthreshold and subthreshold treatments. For example, the lower limit of pulse amplitude can be as low as 0.1 mA, while the upper limit of pulse amplitude can be as high as 20 mA. The lower limit of pulse width can be as low as 2 μs, while the upper limit of pulse width can be as high as 1000 μs. For example, the lower limit of pulse rate can be as low as 1 Hz, while the upper limit of pulse rate can be as high as 50 kHz. In the illustrated embodiment, a pulse amplitude of 5 mA, a pulse width of 210 μs, and a pulse rate of 40 Hz were selected. Therefore, during manual programming mode, the selected coverage area 120 of the selected program 114 can be programmed using a set of modulation parameters designed to deliver overthreshold or subthreshold treatment to the patient.

[0178] like Figure 13 As shown, the electronic drag programming mode is selected. In this mode, the electrode 130 shown in the wire display panel 104, which is separately selectable and configurable in manual programming mode, is only for display and not directly selectable or controllable. Instead of the amplitude / polarity region 144, the parameter selection panel 106 includes a guide arrow array 152, which allows the electric field to be guided up, down, left, or right relative to the electrode 26. In the illustrated embodiment, the current is guided by selecting a virtual multipole (i.e., moving the virtual multipole relative to the actual electrode 26 without changing the basic configuration of the virtual multipole (focus (F) and upper anode percentage (UAP))) and calculating the electric amplitude value required for the actual electrode 26 to simulate the virtual multipole. In the illustrated embodiment, subdivided cathode currents of 40% and 60% are calculated for electrodes E2 and E3, respectively, and subdivided anode currents of 25% and 75% are calculated for electrodes E1 and E4. In response to the guidance of current controlled by the guide arrow array 152, the controller / processor 80 generates a set of modulation parameters (with different subdivided electrode combinations) and transmits the set of modulation parameters to the IPG 14 via the telemetry circuit 86 to deliver modulated energy to the electrode array 26 in a manner that guides the synthesized electric field relative to the electrode array 26.

[0179] In the illustrated embodiment, the virtual multipolar poles used in the electronic drag programming mode are bipolar or tripolar, including a modulated cathode (i.e., cathode modulation is provided in the electronic drag programming mode). Furthermore, the range of pulse rate and pulse width of the modulation parameter set defined during the electronic drag programming mode is limited to those known to cause overthreshold treatment (e.g., causing sensory abnormalities) (assuming a nominal pulse amplitude). For example, the lower limit of the pulse width can be 100 μs, and the upper limit of the pulse rate can be 1500 Hz. In the illustrated embodiment, a pulse amplitude of 5 mA, a pulse width of 210 μs, and a pulse rate of 40 Hz were selected.

[0180] like Figure 14 As shown, the navigation programming mode is selected. As in the electronic drag programming mode, the electrodes shown in the wire display panel 104, which are individually selectable and configurable in the manual programming mode, are only for display and are not directly selectable or controllable in the navigation programming mode. Instead of the amplitude / polarity region 144, the parameter selection panel 106 includes a guide arrow array 162, which allows the electric field to be guided upwards, downwards, leftwards, or rightwards relative to the electrode 26. In the illustrated embodiment, current is guided by weaving one or more anodes around the cathode of the virtual multipole as the cathode is shifted relative to the electrode array 26, and by calculating the electric amplitude values ​​required for the electrode 26 to simulate the virtual multipole. In the illustrated embodiment, subdivided cathode currents of 33%, 47%, and 20% are calculated for electrodes E2, E3, and E4, respectively, and subdivided anode currents of 54% and 46% are calculated for electrodes E1 and E5, respectively. In response to the guidance of current controlled by the guide arrow array 162, the controller / processor 80 generates a set of modulation parameters (with different subdivided electrode combinations) and transmits the set of modulation parameters to the IPG 14 via the telemetry circuit 86 for use in delivering modulated energy to the electrode array 26 in a manner that guides the trajectory of the synthesized electric field relative to the electrode array 26.

[0181] Similar to the electronic drag programming mode, the virtual multi-electrode used in the navigation programming mode is either bipolar or tripolar, and includes a modulated cathode (i.e., cathode modulation is provided in the navigation programming mode). Furthermore, the range of pulse rate and pulse width of the modulation parameter set defined during the electronic drag programming mode is limited to those known to cause overthreshold treatment (e.g., causing sensory abnormalities) (assuming a nominal pulse amplitude). For example, the lower limit of the pulse width can be 100 μs, and the upper limit of the pulse rate can be 1500 Hz. In the illustrated embodiment, a pulse amplitude of 5 mA, a pulse width of 210 μs, and a pulse rate of 40 Hz were selected.

[0182] Further details of the use of the device for seamlessly switching between manual programming mode, electronic dragging programming mode and navigation programming mode are described in U.S. Patent Application Serial No. 13 / 715,751 entitled “Seamless Integration of Different Programming Modes for a Neuromodulation device Programming System”, which is expressly incorporated herein by reference.

[0183] like Figure 15 As shown, the probe programming mode is selected. As in the electronic drag programming mode, the electrodes shown in the wire display panel 104, which are individually selectable and configurable in the manual programming mode, are only for display and are not directly selectable or controllable in the navigation programming mode. Instead of the amplitude / polarity region 144, the parameter selection panel 106 includes a guide arrow array 172, which allows the guide electric field to be directed upwards, downwards, leftwards, or rightwards relative to the electrode 26. In the illustrated embodiment, the current is guided by selecting a virtual monopole and calculating the electric amplitude value required to simulate a virtual multipole for the actual electrode 26. In the illustrated embodiment, 100% of the subdivided cathode current is calculated for the shell electrode, and 36%, 20%, and 44% of the subdivided anode current are calculated for electrodes E4, E9, and E10, respectively. In response to the guidance of current controlled by the guide arrow array 172, the controller / processor 80 generates a set of modulation parameters (with different subdivided electrode combinations) and transmits the set of modulation parameters to the IPG 14 via the telemetry circuit 86 for delivering modulated energy to the electrode array 26 in a manner that guides the synthesized electric field relative to the electrode array 26.

[0184] In the illustrated embodiment, the virtual monopole used in the probe programming mode includes a primary modulated anode (i.e., anode modulation is provided in the probe programming mode), because it is believed that the delivery of anodic current to spinal cord tissue, especially to the neural network of the dorsal horn (as in the U.S. patent application entitled "Method for Selectively Modulating Neural Elements in the DorsalHorn," which is expressly incorporated herein by reference), provides subthreshold pain relief to the patient, although it is also possible that the delivery of cathodic current to spinal cord tissue could also be therapeutic.

[0185] It should also be noted that the use of a virtual monopole ensures that the anodic current targets only the neural tissue of interest. Conversely, if a virtual bipolar or tripolar pole were used, one or more virtual cathodes would have to be located adjacent to the target neural tissue of interest, which could obscure the proper location of the virtual anode by unintentionally causing abnormal sensations experienced by the patient. Furthermore, the current delivered to the patient during the probe programming mode is a biphasic pulse waveform with a passive cathode charge recovery phase, thereby minimizing the possibility that the cathode charge recovery phase might unintentionally cause abnormal sensations experienced by the patient. Moreover, as in the electronic drag programming mode and the navigation programming mode, the range of pulse rate and pulse width of the modulation parameter set defined during the probe programming mode is limited to those known to cause overthreshold treatment (e.g., causing abnormal sensations) (assuming a nominal pulse amplitude). For example, the lower limit of the pulse width could be 100 μs, and the upper limit of the pulse rate could be 1500 Hz. In the illustrated embodiment, a pulse amplitude of 3.9 mA, a pulse width of 250 μs, and a pulse rate of 100 Hz were selected.

[0186] like Figure 16 As shown, the subthreshold programming mode is selected. As in the electronic drag programming mode, the electrodes shown in the lead display panel 104, which are individually selectable and configurable in the manual programming mode, are only for display and are not directly selectable or controllable in the navigation programming mode. Since the patient is unlikely to perceive any sensory abnormalities, the parameter selection panel 106 does not have an amplitude / polarity region 144 or a guide arrow array. Alternatively, the parameter selection panel 106 may have a guide arrow array to adjust the modulation trajectory.

[0187] Regardless, the controller / processor 80 will transform the final virtual anode monopole defined during the probe programming mode into a virtual cathode multipole (i.e., a virtual multipole with a primary modulated cathode). For example, the cathode of the virtual cathode multipole can be placed at the position of the anode of the previously defined virtual anode multipole relative to the electrode array 26, and the focal point (F) and upper electrode percentage (UAP) of the virtual cathode multipole can be assumed to be (e.g., two focal points (i.e., double electrode space) and zero UAP (i.e., virtual bipolar)).

[0188] While the probe programming mode is specifically designed for finding target locations for subthreshold modulation, in an alternative embodiment, the controller / processor 80 can convert a final virtual cathode multipole defined by either the electronic drag programming mode or the navigation programming mode into a virtual cathode multipole. In this case, the anode of the virtual anode multipole can be placed at the location of the cathode of the virtual cathode multipole, and one or more cathodes of the virtual anode multipole can be placed at one or more locations of one or more anodes of the virtual cathode multipole relative to one or more locations of the electrode array 26. In another alternative embodiment, the controller / processor 80 can convert a final subdivided electrode combination defined by the manual programming mode into a virtual cathode multipole. In this case, the controller / processor 80 can convert a manually generated subdivided electrode combination into a virtual cathode multipole in the manner described in U.S. Patent Application Serial No. 13 / 715,751, which is expressly incorporated herein by reference. Therefore, it will be understood that the manual programming mode, electronic drag programming mode, navigation programming mode, and probe programming mode can be seamlessly switched to the subthreshold programming mode.

[0189] Regardless, the controller / processor 80 then calculates the amplitude values ​​required to simulate the virtual cathode multipole for the actual electrodes 26. In the illustrated embodiment, subdivided cathode currents of 44%, 9%, 34%, and 13% are calculated for electrodes E4, E5, E12, and E13, respectively, and subdivided anode currents of 8%, 47%, 37%, and 8% are calculated for electrodes E3, E7, E15, and E16, respectively. In the illustrated embodiment, the virtual multipole used in subthreshold programming mode is a biphasic pulsed waveform with an active cathode charge recovery phase, although this biphasic pulsed waveform can alternatively have an active anode charge recovery phase. In either case, the biphasic pulsed waveform will have an anode phase, which will modulate neural tissue.

[0190] The controller / processor 80 also automatically modifies the previously defined electrical pulse parameters in the graphical controls 136-140 of the parameter adjustment panel 106 to predetermined values ​​to ensure subthreshold modulation during the probe programming mode (or alternatively, manual programming mode, electronic drag programming mode, or navigation programming mode). For example, in the illustrated embodiment, the pulse amplitude is reduced from 3.9 mA to 2.3 mA, the pulse width is reduced from 210 μs to 40 μs, and the pulse rate is increased from 100 Hz to 2 kHz. Typically, preferably, the overthreshold pulse amplitude used in the probe programming mode is reduced by 30% to 70% to obtain a subthreshold pulse amplitude to ensure effective subthreshold therapy. Moreover, although the subthreshold programming mode allows the user to modify the pulse amplitude, pulse width, and pulse rate via manipulation of the graphical controls 136-140 of the parameter adjustment panel 106, the range of pulse amplitude, pulse rate, and pulse width in the set of modulation parameters defined during the probe programming mode is limited to those known to result in subthreshold therapy (e.g., without causing sensory abnormalities). For example, the upper limit of pulse amplitude can be 5mA, the upper limit of pulse width can be 100μs, and the lower limit of pulse rate can be 1500Hz.

[0191] In any of the semi-automatic modes (i.e., electronic towing programming mode, navigation programming mode, or detection programming mode), the parameter adjustment panel 106 includes an advanced tab 154, such as... Figure 13-16 As shown, when actuated, its concealed wiring displays panel 104 and provides contact with resolution control 156 and focus control 158, as... Figure 17 As shown. Resolution control 156 allows for variations in modulation adjustment resolution. In one embodiment, three settings—fine, medium, and coarse—can be selected. Resolution control 156 has "+" and "-" icons for adjusting the resolution. Resolution control 156 also includes a display element to graphically display the current resolution level. When the resolution is set to fine, each change resulting from the use of the guide array causes fewer changes to the electrode configuration than when the resolution is set to medium or coarse. Focus control 158 allows for changing the modulation focus by moving one or more anodes and cathodes of the virtual multipolar poles toward each other to increase the modulation focus or by moving one or more anodes and cathodes of the virtual multipolar poles away from each other to decrease the modulation focus. Focus control 158 has "+" and "-" icons for adjusting the focus. Focus control 158 also includes a display element to graphically display the current focus level. In particular, since the probe programming mode utilizes a virtual monopole assuming an infinite distance between the anodes and cathodes of the virtual multipolar poles, focus control 158 is only available in electronic drag programming mode and navigation programming mode.

[0192] Therefore, it can be understood from the above that the controller / processor 80 is able to obtain a set of modulation parameters (subdivided electrode combinations, pulse amplitude, pulse width, and / or pulse rate) for the subthreshold programming mode from the set of modulation parameters determined prior to the probe programming mode (or alternatively, manual programming mode, electronic drag programming mode, and / or navigation programming mode). The electric field resulting from the delivery of electrical energy to the electrode array 26 according to the new set of modulation parameters defined for the subthreshold programming mode will have the same trajectory as the electric field resulting from the delivery of electrical energy to the multiple electrodes according to the final set of modulation parameters defined for the probe programming mode (or alternatively, manual programming mode, electronic programming mode, and / or navigation programming mode).

[0193] The structure and function of CP 18 have been described; now, refer to... Figure 18 A method for delivering subthreshold therapy to a patient to treat chronic pain is described. First, the SCM system 10 is placed in a probe programming mode (step 240). Then, the SCM system 10 is operated to deliver electrically modulated energy to the patient's spinal cord tissue according to a set of modulation parameters, such that the trajectory of the generated electric field is gradually shifted relative to the tissue (e.g., by manipulating the guide array 172 as discussed above) (step 242). Preferably, each set of modulation parameters defines electrical pulse parameters that may cause abnormal sensory perception in the patient. For example, each set of modulation parameters may define a pulse rate of less than 1500 Hz and / or a pulse width of greater than 100 μs. The delivered electrically modulated energy may be inherently unipolar and may be monophasic or biphasic (with a passive charge recovery phase), such that the polarity of the electrical energy that provides the maximum possible subthreshold therapy can be separated, in this case, the anode portion of the electrical energy. The sets of modulation parameters can be created using the aforementioned dummy poles. In particular, a series of virtual poles relative to the organization can be defined by panning virtual poles across electrodes, and then the amplitude values ​​of electrode combinations simulated separately for the series of virtual poles can be calculated.

[0194] The patient perceives a sensory abnormality in response to the delivery of electrically modulated energy to the tissue, based on at least one of the modulation parameters in the set (step 244). For example, if the patient experiences pain in a body area such as the lower back, the delivery of electrically modulated energy based on at least one of the modulation parameters could cause the patient to perceive a sensory abnormality in the lower back. The set of modulation parameters that leads to the most effective treatment based on feedback from the patient can then be identified (step 246).

[0195] Next, the SCM system 10 is switched to subthreshold programming mode (step 248). In response, a new set of modulation parameters is automatically obtained from the previously identified set of modulation parameters (step 250). The new set of modulation parameters preferably defines electrical pulse parameters that may lead to sensory abnormalities that the patient does not perceive. For example, each set of modulation parameters may define a pulse rate greater than 1500 Hz and / or a pulse width less than 100 μs. The obtained set of modulation parameters can be created using the aforementioned dummy poles. In particular, dummy poles relative to the tissue can be defined, and the amplitude values ​​of electrode combinations simulated separately for the dummy poles can then be calculated.

[0196] The SCM system 10 is then operated to deliver electrically modulated energy to the patient's spinal cord tissue according to a new set of modulation parameters, thereby creating an electric field with a trajectory relative to the spinal cord tissue and without causing sensory abnormalities in the patient (step 252), the trajectory being identical to that of the electric field associated with the identified set of modulation parameters. The delivered electrically modulated energy preferably has an anodic component. For example, the delivered electrically modulated energy can be substantially bipolar and biphase (with an active charge recovery phase). Finally, the SCM system 10 is programmed using the new set of modulation parameters (step 254).

[0197] While specific embodiments of the invention have been shown and described, it will be understood that the invention is not limited to the preferred embodiments and that various changes and modifications can be made without departing from the spirit and scope of the invention, as will be apparent to those skilled in the art. Therefore, the invention is intended to cover alternatives, modifications, and equivalents that may be included within the spirit and scope of the invention as defined in the claims.

Claims

1. An external control device for programming an implantable neuromodulator coupled to an electrode array implanted within a patient with a hybrid modulation program to deliver an effective neuromodulation therapy for treating a disease, wherein, The mixed modulation procedure includes a set of suprathreshold modulation parameters for delivering a suprathreshold neuromodulation therapy effective for treating the disease and a set of subthreshold modulation parameters for delivering a subthreshold neuromodulation therapy effective for treating the disease, the apparatus comprising: a user interface; telemetry circuitry configured to communicate with the neuromodulator; and controller / processor circuitry configured to direct the neuromodulator, via the telemetry circuitry, to deliver suprathreshold electrical modulation energy according to the set of suprathreshold modulation parameters to deliver the suprathreshold neuromodulation therapy effective for treating the disease with perception of paresthesia and to deliver subthreshold electrical modulation energy according to the set of subthreshold modulation parameters to deliver the subthreshold neuromodulation therapy effective for treating the disease without perception of paresthesia in response to input to the user interface, wherein the neuromodulator is further configured to sense at least one evoked compound action potential (eCAP) in a population of neurons at the target tissue site in response to the delivered subthreshold electrical modulation energy of incrementally adjusted amplitude values, and based thereon, the controller / processor circuitry is configured to select one of the incrementally adjusted amplitude values as the perception threshold based on the at least one sensed eCAP.

2. The external control device according to claim 1, wherein The controller / processor circuitry is configured to direct the neuromodulator to simultaneously deliver suprathreshold electrical modulation energy to a first set of electrodes and to deliver subthreshold electrical modulation energy to a second set of electrodes different from the first set of electrodes.

3. The external control device of claim 1, wherein, The controller / processor circuitry is configured to direct the neuromodulator to simultaneously deliver suprathreshold electrical modulation energy as a suprathreshold electrical pulse train in a first temporal channel and to deliver subthreshold electrical modulation energy as a subthreshold electrical pulse train in a second temporal channel such that the pulses of the respective electrical pulse trains do not overlap.

4. The external control device of claim 1, wherein, The controller / processor is configured to direct the neuromodulator to alternately burst on and off the suprathreshold electrical modulation energy and to alternately burst on and off the subthreshold electrical modulation energy such that the bursts of suprathreshold electrical modulation energy and the bursts of subthreshold electrical modulation energy are interleaved with each other.

5. The external control device of claim 1, wherein, The set of suprathreshold modulation parameters defines a first amplitude value and the set of subthreshold modulation parameters defines a second amplitude value less than the first amplitude value.

6. The external control device of claim 5, wherein, The second amplitude value is in a range of 30% to 70% of the first amplitude value.

7. The external control device of claim 5, wherein, The second amplitude value is in a range of 40% to 60% of the first amplitude value.

8. The external control device of claim 1, wherein, The set of suprathreshold modulation parameters defines a pulse rate less than 1500 Hz and the set of subthreshold modulation parameters defines a pulse rate greater than 1500 Hz.

9. The external control device of claim 1, wherein, The set of suprathreshold modulation parameters defines a pulse rate less than 500 Hz and the set of subthreshold modulation parameters defines a pulse rate greater than 2500 Hz.

10. The external control device of claim 1, wherein, The set of suprathreshold modulation parameters defines a pulse width greater than 100 us and the set of subthreshold modulation parameters defines a pulse width greater than 100 us.

11. The external control device of claim 1, wherein, The set of suprathreshold modulation parameters defines a pulse width greater than 200 us and the set of subthreshold modulation parameters defines a pulse width greater than 50 us.

12. The external control device of claim 1, further comprising a housing containing a user interface, a telemetry circuit, and a controller / processor circuit.

13. A neuromodulation system comprising: an electrode array; an implantable neuromodulator coupled to the electrode array; and an external control device configured to direct the neuromodulator to deliver suprathreshold electrical modulation energy according to a suprathreshold modulation parameter set to deliver a suprathreshold modulation therapy effective to treat the disease with perception of paresthesia, and to deliver subthreshold electrical modulation energy according to a subthreshold modulation parameter set to deliver a subthreshold modulation therapy effective to treat the disease without perception of paresthesia; wherein the neuromodulator is further configured to sense at least one evoked compound action potential (eCAP) in a population of neurons at the target tissue location in response to the delivered subthreshold electrical modulation energy of incrementally adjusted amplitude values, and based thereon, the controller / processor circuit is configured to select one of the incrementally adjusted amplitude values as the perception threshold based on the at least one sensed eCAP, wherein the suprathreshold modulation parameter set and the subthreshold modulation parameter set are contained in a hybrid modulation program to deliver the therapy effective to treat the disease. the external control device is configured to direct the neuromodulator to simultaneously deliver the suprathreshold electrical modulation energy to a first set of electrodes and to deliver the subthreshold electrical modulation energy to a second set of electrodes different from the first set of electrodes.

14. The neuromodulation system of claim 13, wherein, the external control device is configured to direct the neuromodulator to simultaneously deliver the suprathreshold electrical modulation energy as a suprathreshold electrical pulse train in a first temporal channel and to deliver the subthreshold electrical modulation energy as a subthreshold electrical pulse train in a second temporal channel such that the pulses of the respective electrical pulse trains do not overlap.

15. The neuromodulation system of claim 13, wherein, the external control device is configured to direct the neuromodulator to alternately burst the suprathreshold electrical modulation energy on and off and to alternately burst the subthreshold electrical modulation energy on and off such that the bursts of the suprathreshold electrical modulation energy and the bursts of the subthreshold electrical modulation energy interleave with each other.

16. The neuromodulation system of claim 13, wherein, the suprathreshold modulation parameter set defines a first amplitude value, and the subthreshold modulation parameter set defines a second amplitude value less than the first amplitude value.

17. The neuromodulation system of claim 13, wherein, the second amplitude value is in a range of 30% to 70% of the first amplitude value.

18. The neuromodulation system of claim 17, wherein, the second amplitude value is in a range of 40% to 60% of the first amplitude value.

19. The neuromodulation system of claim 17, wherein, the suprathreshold modulation parameter set defines a pulse rate less than 1500 Hz, and the subthreshold modulation parameter set defines a pulse rate greater than 1500 Hz.

20. The neuromodulation system of claim 13, wherein, the suprathreshold modulation parameter set defines a pulse rate less than 500 Hz, and the subthreshold modulation parameter set defines a pulse rate greater than 2500 Hz.

21. The neuromodulation system of claim 13, wherein, the suprathreshold modulation parameter set defines a pulse width greater than 100 us, and the subthreshold modulation parameter set defines a pulse width greater than 100 us.

22. The neuromodulation system of claim 13, wherein, the suprathreshold modulation parameter set defines a pulse width greater than 200 us, and the subthreshold modulation parameter set defines a pulse width greater than 50 us.

23. The neuromodulation system of claim 13, wherein, ​

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