Spinal Cord Stimulator System

• US 20140277264A1
• Filed: 03/14/2014
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Cirtec Medical Corp.
• Original Assignee: Globus Medical, Inc.
• Inventors: Fellmeth, Daniel, Khalil, Saif, Angara, Raghavendra, Curtis, Miles, Biele, Christopher
• Granted Patent: US 10,016,602 B2
• Time in Patent Office: Days
• US Class Current: 607/46
• CPC Class Codes: A61N 1/025 Digital circuitry features of electrotherapy devices, e.g. memory, clocks, processors
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/36157 Current A61N1/3616 takes precedence
• CPC Class Codes: A61N 1/36178 Burst or pulse train parameters
• CPC Class Codes: A61N 1/36185 Selection of the electrode configuration
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer
• CPC Class Codes: A61N 1/37241 providing test stimulations
• CPC Class Codes: A61N 1/3752 Details of casing-lead connections
• CPC Class Codes: A61N 1/3754 Feedthroughs
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

Spinal cord stimulation (SCS) system having a recharging system with self alignment, a system for mapping current fields using a completely wireless system, multiple independent electrode stimulation outsource, and IPG control through software on Smartphone/mobile device and tablet hardware during trial and permanent implants. SCS system can include multiple electrodes, multiple, independently programmable, stimulation channels within an implantable pulse generator (IPG) providing concurrent, but unique stimulation fields. SCS system can include a replenishable power source, rechargeable using transcutaneous power transmissions between antenna coil pairs. An external charger unit, having its own rechargeable battery, can charge the IPG replenishable power source. A real-time clock can provide an auto-run schedule for daily stimulation. A bi-directional telemetry link informs the patient or clinician the status of the system, including the state of charge of the IPG battery. Other processing circuitry in current IPG allows electrode impedance measurements to be made.

Claims

1. A spinal cord stimulation device comprising:

an implantable pulse generator comprising;

a circuit assembly housed in the casing, the circuit assembly including and operably interconnected with a plurality of output capacitors, an application specific integrated circuit (ASIC) and a microcontroller;

at least one rechargeable implantable grade lithium ion battery housed in the casing and operably connected with the circuit board and configured to be inductively charged by a Constant Current, Constant Voltage type of regulation;

a charging circuit operably connected with the at least one battery housed in the casing and with the ASIC of the circuit board, the charging circuit having a secondary charging coil, at least one capacitor, at least one resistor, a voltage regulator and a voltage doubler full wave rectifier configured to convert an induced AC voltage into usable DC voltage under power management control by the ASIC;

an external charger comprising;

a primary charging coil;

at least one battery; and

a circuit board operably connected with the primary coil and the at least one rechargeable battery,

wherein the at least one rechargeable battery in the implantable pulse generator is recharged using transcutaneous power transmissions between the primary charging coil and the secondary charging coil.

2. The spinal cord stimulation device of claim 1, wherein the transcutaneous power transmissions between the primary charging coil and the secondary charging coil induce voltage into the secondary charging coil and the voltage is rectified and used to charge the battery.

3. The spinal cord stimulation device of claim 1, wherein capacitors are electrically configured with at least one of the secondary charging coil and the primary charging coil so that the primary and secondary charging coils resonant at a common frequency.

4. The spinal cord stimulation device of claim 1, further comprising an alignment sensor to denote when the primary charging coil and the secondary charging coil are properly aligned, wherein the alignment sensor is configured to provide feedback to indicate alignment.

5. The spinal cord stimulation device of claim 4, wherein the feedback can be audible, visual, or a combination thereof.

6. The spinal cord stimulation device of claim 4, wherein the distance between the primary coil the secondary coil changes the impedance of both the primary coil and the secondary coil and reflected impedance is measured and compared to a fixed threshold.

7. The spinal cord stimulation device of claim 4, wherein alignment can be sensed up to a distance between the primary coil and the secondary coil of up to 30 mm.

8. The spinal cord stimulation device of claim 1, wherein the at least one rechargeable battery has zero-volt technology.

9. The spinal cord stimulation device of claim 1, wherein the at least one external charger battery is rechargeable.

10. The spinal cord stimulation device of claim 1, wherein a Ferrite back-plate is positioned relative to the primary charging coil.

11. The spinal cord stimulation device of claim 1, wherein the primary charging coil is comprised of Litz wire and the secondary charging coil is comprised of wound coated copper magnet wires, the secondary charging coil connected to a capacitor to make a series resonance tank circuit.

12. The spinal cord stimulation device of claim 1, further comprising a battery status notification system including a telemetry link between the implantable pulse generator and a clinician programmer.

13. The spinal cord stimulation device of claim 1, the external charger further comprising:

a Class-E amplifier topology to produce an alternating current in the primary coil around a resonant frequency, including capacitors and an N Channel MOSFET;

an inductor connecting the Class-E amplifier topology to the external charger battery; and

a feedback closed loop control.

14. A method of charging an implantable rechargeable battery provided in a subcutaneously implanted implantable pulse generator comprising:

positioning an external charger over the implantable pulse generator;

aligning a primary coil of the external charger with a secondary coil in the implantable pulse generator until feedback is provided indicating proper alignment;

transmitting transcutaneous power transmissions inductively between the primary charging coil and the secondary charging coil;

inducing a voltage into the secondary charging coil;

charging inductively by a Constant Current, Constant Voltage type of regulation; and

providing a voltage doubler full wave rectifier to convert the induced AC voltage into usable DC voltage and using the rectified voltage to charge the battery.