Abstract: Multi-phasic fields are produced at a neuromodulation site using electrodes. A first phase is directed at a target region such that a first-polarity electrical charge is injected to the target region, and a second phase is directed at portions of the neuromodulation site other than the target region, such that a second-polarity electrical charge opposite the first-polarity electrical charge is injected to those portions of the neuromodulation site to essentially neutralize the first-polarity charge injected at the neuromodulation site while maintaining at least a portion of the first-polarity charge at the target region. In some embodiments, each anode used to produce the first phase is used as a cathode to produce the second phase, and each cathode used to produce the first phase is used as an anode to produce the second phase, and the quantity of charge injected by each electrode in both phases is essentially zero.

Abstract: New lead designs particularly useful in a Spinal Cord Stimulation (SCS) system are disclosed which are useful to sensing neural responses such as Evoked Compound Action Potentials (ECAPs). One or more sensing electrodes on the lead are spaced at significantly larger distances away from the stimulating electrodes, such as at distances in a range of 20 mm to less than 30 mm. Positioning the sensing electrodes at such distances allows for sensing of ECAPs at a sufficient distance away from the stimulating electrodes that ECAP measurements at the sensing electrodes will be less affected by stimulation artifacts that accompany the stimulation. The sensing electrodes may be dedicated to sensing, or may also have the ability to function as stimulating electrodes.

Abstract: Disclosed are systems and methods for providing stimulation using waveforms with long duration phases in a spinal cord stimulator. Simulation shows the effectiveness of using phase durations of greater than 2.0 ms, or even 2.6 ms or greater, in recruiting inhibitory interneurons in the dorsal horn of the spinal cord, or in recruiting dorsal column axons of the dorsal column, both of which promote pain suppression in spinal cord stimulation (SCS) patients. Traditional SCS devices may not allow the programming of phase durations of such lengths, and so examples of how long phase durations can be effectively created is shown by way of a non-limiting example, preferably in a single timing channel. The waveforms preferably have at least two phases of opposite polarities, at least one of which is long, although phases may be split into sub-phases. The waveforms may be charge balanced at each electrode.

Abstract: A method and external control device for providing therapy to a patient using first and second electrodes implanted within the patient is provided. A train of electrical multi-phasic pulses is generated. A first electrical current is sourced from the second electrode and at least a portion of the first electrical current is sunk to the first electrode during a stimulation phase of each multi-phasic pulse, thereby therapeutically stimulating a first tissue region adjacent the first electrode. A second electrical current is sourced from the first electrode and at least a portion of the second electrical current is sunk to the second electrode during a charge recovery phase of each multi-phasic pulse, thereby recovering at least a portion of the charge that had been injected into the patient during the stimulation phase of each multi-phasic pulse, and therapeutically stimulating a second tissue region adjacent the second electrode.

Abstract: An algorithm programmed into the control circuitry of a rechargeable-battery Implantable Medical Device (IMD) is disclosed that can adjust the charging current (Ibat) provided to the rechargeable battery over time (e.g., the life of the IMD) in accordance with one or more of the parameters having an effect on rechargeable battery capacity, such as number of charging cycles, charging current, discharge depth, load current, and battery calendar age. The algorithm consults such parameters as stored over the history of the operation of the IMD in a parameter log, and in conjunction with a battery capacity database reflective of the effect of these parameters on battery capacity, estimates a change in the capacity of the battery, and adjust the charging current in one or both of trickle and active charging paths to slow the loss of battery capacity and extend the life of the IMD.

Abstract: Waveforms for a stimulator device, and methods and circuitry for generating them, are disclosed having high- and low-frequency aspects. The waveforms comprise a sequence of pulses issued at a low frequency which each pulse comprising first and second charge-balanced phases. One or both of the phases comprises a plurality a monophasic sub-phase pulses issued at a high frequency in which the sub-phase pulses are separated by gaps. The current during the gaps in a phase can be zero, or can comprise a non-zero current of the same polarity as the sub-phase pulses issued during that phase. The disclosed waveforms provide benefits of high frequency stimulation such as the promotion of paresthesia free, sub-threshold stimulation, but without drawbacks inherent in using high-frequency biphasic pulses.

Abstract: A method of treating an ailment suffered by a patient using one or more electrodes adjacent spinal column tissue of the patient, comprises delivering electrical modulation energy from the one or more electrodes to the spinal column tissue in accordance with a continuous bi-phasic waveform having a positive phase and a negative phase, thereby modulating the spinal column tissue to treat the ailment. An implantable electrical modulation system, comprises one or more electrical terminals configured for being coupled to one or more modulation leads, output modulation circuitry capable of outputting electrical modulation energy to the electrical terminal(s) in accordance with a continuous bi-phasic waveform, and control circuitry configured for modifying a shape of the continuous bi-phasic waveform, thereby changing the characteristics of the electrical modulation energy outputted to the electrode(s).

Abstract: Architectures for implantable stimulators having N electrodes are disclosed. The architectures contains X current sources, or DACs. In a single anode/multiple cathode design, one of the electrodes is designated as the anode, and up to X of the electrodes can be designated as cathodes and independently controlled by one of the X DACs, allowing complex patient therapy and current steering between electrodes. The design uses at least X decoupling capacitors: X capacitors in the X cathode paths, or one in the anode path and X?1 in the X cathode paths. In a multiple anode/multiple cathode design having X DACs, a total of X?1 decoupling capacitors are needed. Because the number of DACs X can typically be much less than the total number of electrodes (N), these architectures minimize the number of decoupling capacitors which saves space, and ensures no DC current injection even during current steering.

Abstract: Improved external chargers for charging an implantable medical device, and particularly useful in charging a plurality of such devices, are disclosed. Each of the various embodiments include a plurality of field customization coils for customizing the magnetic charging field generated by the external charger such that the magnetic charging field is not radially symmetric. For example, one embodiment includes a primary coil with a plurality of field customization coils distributed radially with respect to the coil. The generated magnetic charging field can be rendered radially asymmetric by selectively activating or disabling the field customization coils in response to data quantifying the coupling between the various implants and the field customization coils in the charger.

Abstract: A computer implemented system and method generates a patient-specific model of patient response to stimulation on a neural element basis, receives user-input of target neuromodulation sites, and, based on the patient-specific model, determines which stimulation paradigm and settings, including stimulation sites, would result in the target neuromodulation, where the stimulation sites are not necessarily the same as the resulting neuromodulation sites. The system outputs a visual representation of the stimulation sites that would result in the target neuromodulation. The system monitors a system state and/or patient state and dynamically changes which stimulation program to implement based on the state.

Abstract: Medical device systems and methods for providing spinal cord stimulation (SCS) are disclosed. The SCS systems and methods provide therapy below the perception threshold of the patient. The methods and systems are configured to measure neurological responses to stimulation and use the neurological responses as biomarkers to maintain and adjust therapy. An example of neurological responses includes an evoked compound action potential (ECAP).

Abstract: An external control device, neuromodulation system, and method of providing therapy to a patient using an implantable neuromodulator implanted within the patient. Electrical modulation energy is delivered from the neuromodulator to the patient in accordance with the pre-existing modulation program when in one of the super-threshold delivery mode and the sub-threshold delivery mode. Operation of the neuromodulator is switched to the other of the super-threshold delivery mode and the sub-threshold delivery mode. A new modulation program may be derived from a pre-existing modulation program, and the neuromodulator may deliver the electrical modulation energy to the patient in accordance with the pre-existing modulation program during the other of the super-threshold delivery mode and the sub-threshold delivery mode.

Abstract: An external control device and method for programming an implantable neuromodulator coupled to an electrode array implanted adjacent tissue of a patient having a medical condition. Electrical modulation energy is conveyed to tissue of the patient in accordance with a series of modulation parameter sets. The patient perceives paresthesia in response to the conveyance of the electrical modulation energy to the tissue in accordance with at least one of the modulation parameter sets. One of the modulation parameter set(s) is identified based on the perceived paresthesia. Another modulation parameter set is derived from the identified modulation parameter set. Electrical modulation energy is conveyed to the tissue of the patient in accordance with the other modulation parameter set without causing the patient to perceive paresthesia.

Abstract: A method for configuring stimulation pulses in an implantable stimulator device having a plurality of electrodes is disclosed, which method is particularly useful in adjusting the electrodes by current steering during initialization of the device. In one aspect, a set of ideal pulses for patient therapy is determined, in which at least two of the ideal pulses are of the same polarity and are intended to be simultaneous applied to corresponding electrodes on the implantable stimulator device during an initial duration. These pulses are reconstructed into fractionalized pulses, each comprised of pulse portions. The fractionalized pulses are applied to the corresponding electrodes on the device during a final duration, but the pulse portions of the fractionalized pulses are not simultaneously applied during the final duration.

Abstract: Apparatus and methods for charging an implanted medical device.

Abstract: Architectures for implantable stimulators having N electrodes are disclosed. The architectures contains X current sources, or DACs. In a single anode/multiple cathode design, one of the electrodes is designated as the anode, and up to X of the electrodes can be designated as cathodes and independently controlled by one of the X DACs, allowing complex patient therapy and current steering between electrodes. The design uses at least X decoupling capacitors: X capacitors in the X cathode paths, or one in the anode path and X?1 in the X cathode paths. In a multiple anode/multiple cathode design having X DACs, a total of X?1 decoupling capacitors are needed. Because the number of DACs X can typically be much less than the total number of electrodes (N), these architectures minimize the number of decoupling capacitors which saves space, and ensures no DC current injection even during current steering.

Abstract: Systems of techniques for controlling charge flow during the electrical stimulation of tissue. In one aspect, a method includes receiving a charge setting describing an amount of charge that is to flow during a stimulation pulse that electrically stimulates a tissue, and generating and delivering the stimulation pulse in a manner such that an amount of charge delivered to the tissue during the stimulation pulse accords with the charge setting.

Abstract: An electrical-stimulation lead includes a body having a distal portion, a proximal portion, and a perimeter; electrodes disposed along the distal portion of the body and including segmented electrodes that each extend around no more than 50% of the perimeter of the body; terminals disposed along the proximal portion of the body; and conductors electrically-coupling the terminals to the electrodes; and at least one anchoring unit disposed along the distal portion of the body and configured and arranged for resisting rotation of the body and electrodes relative to patient tissue upon implantation of the lead. Each anchoring unit includes a lead-attachment element and at least one anchoring element attached to the lead-attachment element. The anchoring element extends away from the lead-attachment element and is configured and arranged for physically contacting patient tissue and resisting rotation of the body in proximity to the anchoring element.

Abstract: An example of a system for comparing neurostimulation waveforms can include a user interface configured to receive user input that at least partially defines a first neurostimulation waveform with at least one of differing pulses and differing pulse intervals, where the user input including at least one received parameter of the first neurostimulation waveform. The system can include a storage device configured to store at least one parameter of at least one second neurostimulation waveform, a comparator configured to compare the at least one received parameter of the first neurostimulation waveform to a corresponding at least one parameter of at least one second neurostimulation waveform stored in a memory, the user interface configured to generate and display to the user an indication of a similarity between the compared parameters.

Abstract: An example of a method performed by an implantable medical device (IMD) to deliver a therapy to a patient may include delivering the therapy to the patient, detecting a trigger that is controlled by the patient or a caregiver to the patient, and determining if at least one feature of the IMD for responding to a trigger is enabled. The IMD may be configured to allow the patient or the caregiver to the patient to enable the at least one feature. The method may further include, when the at least one feature is enabled, automatically implementing the at least one enabled feature in response to the detected trigger, including automatically suspending the therapy in response to the detected trigger and automatically restoring the therapy after a defined period after the detected trigger.