Abstract: Medical device recharging systems include a controller and a separate recharge device that communicate wirelessly together to provide recharging to an implantable medical device. Either the controller or the recharge device may also communicate wirelessly with the implantable medical device to obtain recharge status and other information. There may be multiple recharge devices present within communication range of the controller, and the controller may determine which recharge device to activate depending upon proximity of each recharge device to the implantable medical device. The controller may allow the recharge device that is active at any given time to change so that the patient having the implantable medical device can move about in the area where the recharge devices are located while recharging continues.

Abstract: A system and method for determining, during a recharge session, an amount of time until a subsequent recharge session is required to charge a rechargeable power source of an implantable medical device. A model allows a determination of the time until recharge without suspending charging during the recharge session by basing the determination on an initial measured battery voltage and a present current into the rechargeable power source. Alternatively, charging is suspended during the recharge session, and voltage measurements are taken, after which time charging is resumed, without patient input or suspending the recharge session.

Abstract: Exemplary systems include a stimulator configured to be implanted within a patient, the stimulator having a body defined by at least one side surface disposed in between distal and proximal end surfaces, and a connector assembly configured to be coupled to the stimulator and extend parallel to the at least one side surface of the stimulator. The connector assembly is further configured to facilitate removable coupling of a lead having one or more electrodes disposed thereon to the stimulator.

Abstract: The disclosed invention varies the width of the energy pulses with constant frequency and constant amplitude to regulate the amount of energy transferred from an energy transmitting device placed outside a patient to an energy receiver inside the patient. The pulse width is achieved with a modulation technique, PWMT, to control the amount of energy transferred from the external energy transmitting coil in the system to the implanted receiver. The PWMT is used to digitally vary the amount of power from the power amplifier that drives the transmitting coil. Compared to previous analog systems a PWM system is a great deal more efficient and can easily be controlled from a digital domain system such as a microprocessor.

Abstract: An improved external charger for a battery in an implantable medical device (implant), and technique for charging the battery using such improved external charger, is disclosed. In one example, simulation data is used to model the power dissipation of the charging circuitry in the implant at varying levels of implant power. A power dissipation limit is chosen to constrain the charging circuitry from producing an inordinate amount of heat to the tissue surrounding the implant, and duty cycles are determined for the various levels of input intensities to ensure that the power limit is not exceeded. A maximum simulated average battery current determines the optimal (i.e., quickest) battery charging current, and at least an optimal value for a parameter indicative of that current, for example, the voltage across the battery charging circuitry, is determined and stored in the external charger.

Abstract: User interface for external power source, recharger, for an implantable medical device. At least some of patient controls and display icons of an energy transfer unit are common with at least some of the patient controls and the display icons of a patient control unit. An energy transfer unit is operable by the patient with less than three operative controls to control energy transfer from the external energy transfer unit to the implantable medical device. An external antenna having a primary coil can inductively transfer energy to a secondary coil of the implantable medical device when the external antenna is externally placed in proximity of the secondary coil. An energy transfer unit has an external telemetry coil allowing the energy transfer unit to communicate with the implantable medical device through the internal telemetry coil in order to at least partially control the therapeutic output of the implantable medical device.

Abstract: System for transcutaneous energy transfer. An implantable medical device, adapted to be implanted in a patient, has componentry for providing a therapeutic output. The implantable medical device has an internal power source and a secondary coil operatively coupled to the internal power source. An external power source, having a primary coil, provides energy to the implantable medical device when the primary coil of the external power source is placed in proximity of the secondary coil of the implantable medical device and thereby generates a current in the internal power source. An alignment indicator reports the alignment as a function of the current generated in the internal power source with a predetermined value associated with an expected alignment between the primary coil and secondary coil.

Abstract: In one embodiment, an external charging device for recharging an implanted medical device, comprises: a battery for powering the external charging device; a coil for radiating RF power; drive circuitry for driving the coil according to a duty cycle; circuitry for generating a signal that is indicative of an amount of current flowing through the coil; and control circuitry for controlling the drive circuitry, wherein the control circuitry is operable to process the signal from the circuitry for generating to detect when a coil of the implantable medical device temporarily ceases absorbing RF power, the control circuitry modifying the duty cycle in response to detection of the coil of the implantable medical device temporarily ceasing absorbing RF power.

Abstract: A mechanism for transferring energy from an external power source to an implantable medical device is disclosed. A sensor may be used to measure a parameter that correlates to a temperature of the system that occurs during the transcutaneous coupling of energy. For example, the sensor may measure temperature of a surface of an antenna of the external power source. The measured parameter may then be compared to a programmable limit. A control circuit such as may be provided by the external power source may then control the temperature based on the comparison. The programmable limit may be, for example, under software control so that the temperature occurring during transcutaneous coupling of energy may be modified to fit then-current circumstances.

Abstract: Method and systems for optimizing acoustic energy transmission in implantable devices are disclosed. Transducer elements transmit acoustic locator signals towards a receiver assembly, and the receiver responds with a location signal. The location signal can reveal information related to the location of the receiver and the efficiency of the transmitted acoustic beam received by the receiver. This information enables the transmitter to target the receiver and optimize the acoustic energy transfer between the transmitter and the receiver. The energy can be used for therapeutic purposes, for example, stimulating tissue or for diagnostic purposes.

Abstract: Far field telemetry operations are conducted between an external device and an implantable medical device while power is being transferred to the implantable medical device for purposes of recharging a battery of the implantable medical device. The far field operations may include exchanging recharge information that has been collected by the implantable medical device which allows the external device to exercise control over the recharge process. The far field operations may include suspending far field telemetry communications for periods of time while power continues to be transferred where suspending far field telemetry communications may include powering down far field telemetry communication circuits of the implantable medical device for periods of time which may conserve energy. The far field operations may further include transferring programming instructions to the implantable medical device.

Abstract: A system for recharging an implantable medical device. The system comprises a holster that may be donned in multiple respective configurations for charging implanted medical devices implanted at various locations within the patient's body. The system may further comprise a charging unit having an antenna on the patient's right side, a second configuration for charging a pectorally implanted medical device on the patient's left side, or a third configuration for use as a waist belt for charging a pectorally implanted medical device on either side of the patient.

Abstract: A particular method of providing power to an implantable medical device includes providing a first signal to a primary coil that is inductively coupled to a secondary coil of an implantable medical device. The method also include determining a first alignment difference between a voltage corresponding to the first signal and at least one of a current corresponding to the first signal and a component voltage at a component of a primary coil circuit. The method further includes determining a frequency sweep range based on the first alignment difference. The method also includes performing a frequency sweep over the frequency sweep range.

Abstract: In general, the disclosure relates to implantable medical devices including rechargeable power sources. In one example, the disclosure relates to a device including a rechargeable power source, a recharge module configured to recharge the rechargeable power source via inductive energy transfer, a posture state sensor configured to generate posture sensor data; and a processor. The processor may be configured to determine recharge coupling efficiency during a recharge session, receive posture sensor data generated by the posture sensor during the recharge session, and associate the recharge coupling efficiency determined during the recharge session with the posture sensor data.

Abstract: The present disclosure involves a charging system for charging an implanted medical system. The charging device includes a replenishable power supply. The charging device includes a coil assembly electrically coupled to the power supply. The coil assembly includes a primary coil and a plurality of sense coils positioned proximate to the primary coil. The charging device includes electrical circuitry operable to: measure an electrical parameter of the coil assembly; and determine a position of the coil assembly relative to a position of the implanted medical device based on the measured electrical parameter. The charging device includes a visual communications interface operable to: receive an input from the electrical circuitry; and visually display on a screen the position of the coil assembly relative to the position of the implanted medical device based on the input received from the electrical circuitry.

Abstract: By incorporating magnetic field sensing coils in an external charger, it is possible to determine the position of an implantable device by sensing the reflected magnetic field from the implant. In one embodiment, two or more field sensing coils are arranged to sense the reflected magnetic field. By comparing the relative reflected magnetic field strengths of the sensing coils, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.

Abstract: Disclosed is an implantable biomedical device that incorporates an electrical energy generator. The electrical energy generator harvests kinetic energy from voluntary motor activity of a human or animal and converts the kinetic energy to usable electrical energy which is used to power the biomedical device. In certain embodiments, the electrical energy generator includes a housing, an electrical conductor, an electromagnetically active mass, springs connecting the mass to the housing, and electrically circuitry to generate a usable source of electrical power for the biomedical device.

Abstract: Techniques are disclosed for recharging an Implantable Medical Device (IMD). In one embodiment, a first external coil is positioned on one side of a patient's body, such as on a front side of the torso in proximity to the IMD. A second external coil is positioned on an opposite side of the patient's body, such as on the back of the torso. A recharging device generates a current in each of the coils, inductively coupling the first and the second coils to the secondary recharge coil of the IMD. According to another aspect, each of the two external coils may wrap around a portion of the patient's body, such as the torso or head, and are positioned such that the IMD lies between the coils. According to this aspect, current generated in the coils inductively couples to a second recharge coil that is angled within the patient's body.

Abstract: An improved external charger for a battery in an implantable medical device (implant), and technique for charging batteries in multiple implants using such improved external charger, is disclosed. During charging, values for a parameter measured in the implants are reported from the implants to the external charger. The external charger infers from the magnitudes of the parameters which of the implants has the highest and lowest coupling to the external charger, and so designates those implants as “hot” and “cold.” The intensity of the magnetic charging field is optimized for the cold implant consistent with the simulation to ensure that that the cold implant is charged with a maximum (fastest) battery charging current. The duty cycle of the magnetic charging field is also optimized for the hot implant consistent with the simulation to ensure that the hot implant does not exceed the power dissipation limit.

Abstract: A system for treating chronic inflammation may include an implantable microstimulator, a wearable charger, and optionally an external controller. The implantable microstimulator may be implemented as a leadless neurostimulator implantable in communication with a cervical region of a vagus nerve. The microstimulator can address several types of stimulation including regular dose delivery. The wearable charger may be worn around the subject's neck to rapidly (<10 minutes per week) charge an implanted microstimulator. The external controller may be configured as a prescription pad that controls the dosing and activity of the microstimulator.

Abstract: A system and method of controlling the charging of the battery of a medical device using a remote inductive charger, with the method utilizing both a relatively fast closed-loop charging control based on a proxy for a target power transmission value in conjunction, and a slower closed-loop control based on an actual measured transmission value to control a charging power level for charging the medical device.

Abstract: An exemplary system for communicating with an implantable stimulator includes a coil configured to transmit a signal modulated with either on-off keying (OOK) modulation or Frequency Shift Keying (FSK) modulation. The system further includes a first telemetry receiver in the implantable stimulator configured to receive the signal in accordance with the OOK modulation and a second telemetry receiver in the implantable stimulator configured to receive the signal in accordance with the FSK modulation.

Abstract: Disclosed are a system and a method for artificial nerve networking capable of restoring a damaged nerve and allowing selective detection, analysis, transmission and stimulation of a signal from the damaged nerve. The artificial nerve networking system according to an embodiment of the present disclosure includes: a first nerve conduit connected at one end of a damaged nerve; a second nerve conduit connected at the other end of the damaged nerve; and an artificial nerve networking unit electrically connected to the first nerve conduit and the second nerve conduit and recovering the function of the damaged nerve by transmitting and receiving a signal to and from the damaged nerve.

Abstract: Some embodiments of the present disclosure may include a device for conveying power from a location external to a subject to a location within the subject The device may include a flexible carrier, an adhesive on a first side of the carrier, a coil of electrically conductive material associated with the flexible carrier, and a mechanical connector extending from a second side of the carrier opposite the adhesive. The mechanical connector may be configured to be received by and retained by a receiver associated with a housing configured for mounting on the carrier.

Abstract: A device for powering an implant within a body of a subject from a location external to the subject, wherein the implant requires a threshold rate of power increase in order to operate in at least one mode, may include an antenna configured to wirelessly transmit energy to the implant. The device may also include a power storage unit configured to store energy from a power source incapable of delivering the threshold rate of power increase to enable the implant unit to operate in the at least one mode and a power release unit configured to release a pulse of energy from the power storage unit to the antenna after the power storage unit collects an amount of energy sufficient to enable the implant unit to operate in the at least one mode.

Abstract: An implantable microstimulator configured to be implanted beneath a patient's skin for tissue stimulation employs a bi-directional RF telemetry link for allowing data-containing signals to be sent to and from the implantable microstimulator from at least two external devices. Further, a separate electromagnetic inductive telemetry link allows data containing signals to be sent to the implantable microstimulator from at least one of the two external devices. The RF bidirectional telemetry link allows the microstimulator to inform the patient or clinician regarding the status of the microstimulator device, including the charge level of a power source, and stimulation parameter states. The microstimulator has a cylindrical hermetically sealed case having a length no greater than about 27 mm and a diameter no greater than about 3.3 mm. A reference electrode is located on one end of the case and an active electrode is located on the other end of the case.

Abstract: Exemplary cochlear implant systems include an implantable head module configured to be implanted within a head of a patient. The implantable head module includes a cochlear stimulator configured to be coupled to an electrode lead, the electrode lead including one or more electrodes configured to be in communication with one or more stimulation sites within the patient. The implantable head module also includes a signal receiver configured to receive a telemetry signal representative of an audio signal from a signal transmitter located external to the patient, a sound processor configured to process the telemetry signal and direct the cochlear stimulator to generate and apply electrical stimulation representative of the audio signal to the one or more stimulation sites via the electrode lead, and a power receiver configured to receive power for operating the implantable head module from a power transmitter located external to the patient.

Abstract: An improved external charger for an implantable medical device is disclosed in which charging is at least partially controlled based on a sensed pressure impingent on its case, which pressure is indicative of the pressure between the external charger and a patient's tissue. The improved external charger includes pressure detection circuitry coupled to one or more pressure sensors for controlling the external device in accordance with the sensed impingent pressure. The sensed pressure can be used to control charging, for example, by suspending charging, by adjusting a maximum set point temperature for the external charger based on the measured pressure, or by issuing an alert via a suitable user interface. By so controlling the external charger on the basis of the measured pressure, the external charger is less likely to create potentially problematic or uncomfortable conditions for the user.

Abstract: A particular method of providing power to an implantable medical device includes providing a first signal to a primary coil that is inductively coupled to a secondary coil of an implantable medical device. The method also include determining a first alignment difference between a voltage corresponding to the first signal and at least one of a current corresponding to the first signal and a component voltage at a component of a primary coil circuit. The method further includes determining a frequency sweep range based on the first alignment difference. The method also includes performing a frequency sweep over the frequency sweep range.

Abstract: A method for delivering energy as a function of degree coupling may utilize an external unit configured for location external to a body of a subject and at least one processor associated with the implant unit and configured for electrical communication with a power source. The method may determine a degree of coupling between the primary antenna and a secondary antenna associated with the implant unit, and regulate delivery of power to the implant unit based on the degree of coupling between the primary antenna and the secondary antenna.

Abstract: An improved external charger for an implantable medical device is disclosed in which charging is at least partially controlled based on a sensed pressure impingent on its case, which pressure is indicative of the pressure between the external charger and a patient's tissue. The improved external charger includes pressure detection circuitry coupled to one or more pressure sensors for controlling the external device in accordance with the sensed impingent pressure. The sensed pressure can be used to control charging, for example, by suspending charging, by adjusting a maximum set point temperature for the external charger based on the measured pressure, or by issuing an alert via a suitable user interface. By so controlling the external charger on the basis of the measured pressure, the external charger is less likely to create potentially problematic or uncomfortable conditions for the user.

Abstract: A medical device may be configured to transmit energy from a position outside of a subject's body to a position inside the subject's body. The device may include a flexible substrate having a thickness of between 5 and 100 micrometers and a flexible antenna comprising between 10 and 15 windings on a first surface of the flexible substrate, the antenna having a transmission frequency of between 6.4 to 8.3 MHz, and wherein the antenna is configured to transmit energy to a penetration depth of at least 1 cm into the subject's body. The device may also include an adhesive disposed on at least one surface of the flexible substrate for adhering to skin of the subject.

Abstract: An external charging system for charging or powering an implantable medical device is disclosed which is self-affixing to the patient without the need for a holding device. The charging system can comprise two modules attached to opposite ends of a flexible member. The flexible member is bendable, and when bent will firmly hold its position on the patient. The two modules can comprise a coil module containing a charging coil, and an electronics module including a user interface and the necessary electronics for activating the charging coil to produce a magnetic charging field. Wires can couple the charging coil in the coil module to the electronics in the electronics modules. The entire assembly can be encased in a water proof sleeve having a high-friction surface, which protects the charging system and helps the charging system to adhere to the patient.

Abstract: Described is an apparatus and method for increasing a gain of a transmitted power signal in a wireless link when operating in a mid field wavelength that is within a range between wavelength/100 to 100*wavelength and within a medium having a complex impedance between a transmit antenna and a receive antenna. The apparatus and method maximize the gain in the wireless link using simultaneous conjugate matching, to increase power transfer within the transmitted power signal, wherein the simultaneous conjugate matching accounts for interaction between the transmit antenna and the receive antenna, including the complex impedance of the medium between the transmit antenna and the receive antenna.

Abstract: A magnetic arrangement is described for an implantable system for a recipient patient. A planar coil housing contains a signal coil for transcutaneous communication of an implant communication signal. A first attachment magnet is located within the plane of the coil housing and rotatable therein, and has a magnetic dipole parallel to the plane of the coil housing for transcutaneous magnetic interaction with a corresponding second attachment magnet.

Abstract: A transcutaneous energy transfer system, transcutaneous charging system, external power source, external charger and methods of transcutaneous energy transfer and charging for an implantable medical device and an external power source/charger. The implantable medical device has a secondary coil adapted to be inductively energized by an external primary coil at a carrier frequency. The external power source/charger has a primary coil and circuitry capable of inductively energizing the secondary coil by driving the primary coil at a carrier frequency adjusted to the resonant frequency to match a resonant frequency of the tuned inductive charging circuit, to minimize the impedance of the tuned inductive charging circuit or to increase the efficiency of energy transfer.

Abstract: By incorporating magnetic field-inducing position determination coils (PDCs) in an external charger, it is possible to determine the position of an implantable device by actively inducing magnetic fields using the PDCs and sensing the reflected magnetic field from the implant. In one embodiment, the PDCs are driven by an AC power source with a frequency equal to the charging coil. In another embodiment, the PDCs are driven by an AC power source at a frequency different from that of the charging coil. By comparing the relative reflected magnetic field strengths at each of the PDCs, the position of the implant relative to the external charger can be determined. Audio and/or visual feedback can then be communicated to the patient to allow the patient to improve the alignment of the charger.

Abstract: An electrical neuromodulation system and method of treating an ailment of a patient using a neuromodulation device. Electrical modulation energy is delivered at a first frequency from the neuromodulation device to a first set of electrodes having a first combined electrode impedance. A second set of electrodes having a second combined electrode impedance less than the first combined electrode impedance is automatically selected. The electrical modulation energy is delivered at a second frequency to the second set of electrodes, wherein the second frequency is greater than the first frequency.

Abstract: An active implantable medical device comprising a therapeutic device, a controller and at least one rechargeable battery, wherein a single hermetically sealed housing encapsulates a therapeutic device, controller and rechargeable battery. A hermetically sealed housing additionally encapsulates a wireless interface and a commutator.

Abstract: Improved methods and devices for communicating via radio frequency (RF) in transcutaneous energy transfer (TET) systems is provided. In particular, an improved implantable coil for use in a transcutaneous energy transfer (TET) system is provided having an integrated radio frequency (RF) antenna. Further, a method of communicating between an external device and an implanted device having a plurality of secondary coils with integrated RF antennas is also provided.

Abstract: A medical implant, including a first power storage device, a first switching circuit for receiving power and transferring the received power from an implant connector electrically connected to the medical implant to the first power storage device in a first power transfer stage, a second power storage device, and a second switching circuit for transferring power from the first power storage device to the second power storage device in a second power transfer stage.

Abstract: A method of making a custom mold and the custom mold itself having a first layer, a second layer, and a tail that are formed around the bulging area of an implantable medical device (IMD) are presented. The moldable material during hardening is flattened to form a docking platform for the flat planar bottom of an external antenna. The final apparatus of an antenna support may have all the custom contours of the patient's body around the implanted IMD. An optional tape patch and/or bandage may help maintain a proper placement of the external antenna over the IMD depending on amount of mobility the patient wishes to have during charging. An alternate embodiment uses magnets to secure an external antenna over a metallic segment of an IMD.

Abstract: An improved architecture for an implantable medical device using a primary battery is disclosed which reduces the need for boosting the voltage of the primary battery, and hence reduces the power draw in the implant. The architecture includes a boost converter for boosting the voltage of the primary battery and for supplying that boosted voltage to certain of the circuit blocks, which is particularly useful if the battery voltage is necessarily lower than the minimal input power supply voltage necessary for the circuit blocks to operate. However, circuitry capable of operation even at low battery voltages—including the telemetry tank circuitry and the compliance voltage generator—receives the battery voltage directly without boosting, thus saving power.

Abstract: The disclosed invention varies the width of the energy pulses with constant frequency and constant amplitude to regulate the amount of energy transferred from an energy transmitting device placed outside a patient to an energy receiver inside the patient. The pulse width is achieved with a modulation technique, PWMT, to control the amount of energy transferred from the external energy transmitting coil in the system to the implanted receiver. The PWMT is used to digitally vary the amount of power from the power amplifier that drives the transmitting coil. Compared to previous analog systems a PWM system is a great deal more efficient and can easily be controlled from a digital domain system such as a microprocessor.

Abstract: An electronically commutated motor (ECM) includes windings, a power switch, an infrared transceiver and an electromagnetic shield. The power switch is configured to provide pulse width modulated (PWM) power signals to the windings and to generate a substantial level of electromagnetic noises at PWM frequencies during its switching operation. The infrared transceiver is configured to communicate with an external device using infrared signals and convert electrical signals from and to infrared signals that carry data. The electromagnetic shield is configured to substantially shield the infrared transceiver from the electromagnetic noises of PWM frequencies from the power switch.

Abstract: An implantable assembly is disclosed comprising a diode device charging assembly having the means for transferring thermal energy from a living organism to a diode device, means for creating electrical energy from said thermal energy, and means for charging an implantable device with said electrical current. The diode device of this invention is a thermotunneling or thermionic converter. In a preferred embodiment the electrodes of the diode device have been modified to reduce their work function by through the addition a periodically repeating structure comprised of one or more indentations of the dimensions so as to create de Broglie wave interference, leading to a change in electron work function. The implantable assembly utilizes a temperature difference in a body to efficiently generate energy to be harnessed by a wide range of devices.

Abstract: A lead for an implantable device includes a flexible, implantable tether, electrically connectable to an implantable device, and a plurality of control elements, disposed along the tether. The control elements are electrically interconnectable to the implantable device and configured to transmit one of power and communication signals thereto.

Abstract: A particular method of providing power to an implantable medical device includes providing a first signal to a primary coil that is inductively coupled to a secondary coil of an implantable medical device. The method also include determining a first alignment difference between a voltage corresponding to the first signal and at least one of a current corresponding to the first signal and a component voltage at a component of a primary coil circuit. The method further includes determining a frequency sweep range based on the first alignment difference. The method also includes performing a frequency sweep over the frequency sweep range.

Abstract: Receiver-stimulator with folded or rolled up assembly of piezoelectric components, causing the receiver-stimulator to operate with a high degree of isotropy are disclosed. The receiver-stimulator comprises piezoelectric components, rectifier circuitry, and at least two stimulation electrodes. Isotropy allows the receiver-stimulator to be implanted with less concern regarding the orientation relative the transmitted acoustic field from an acoustic energy source.

Abstract: An implantable transcutaneous energy transfer device secondary coil module includes a housing, a secondary coil, power conditioning circuitry, and a low voltage, high power connector. The transcutaneous energy transfer secondary coil is disposed outside the housing and is configured to receive a time-varying magnetic field provided by a transcutaneous energy transfer primary coil, and to convert the time-varying magnetic field into a high voltage, alternating current electric signal within the coil. The power conditioning circuitry is mounted within the housing and is electrically coupled to the secondary coil. The power conditioning circuitry including electronics for converting the high voltage, alternating current electric signal from the secondary coil into a high power, low voltage direct current electric signal.