Method, Apparatus and System for Bipolar Charge Utilization During Stimulation by an Implantable Medical Device

• US 20090192567A1
• Filed: 01/25/2008
• Published: 07/30/2009
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: LivaNova USA, Inc. (LivaNova Plc)
• Original Assignee: Cyberonics, Inc
• Inventors: Scott, Timothy L., Maschino, Steven E., Armstrong, Randolph K.
• Granted Patent: US 8,260,426 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362

Abstract

We disclose a method, apparatus, and system of treating a medical condition in a patient using an implantable medical device. A first electrode is coupled to a first portion of a cranial nerve of the patient. A second electrode is coupled to a second portion of the cranial nerve of the patient. A first electrical signal is provided to the first and second electrodes. The first electrical signal is provided in a first polarity configuration in which the first electrode functions as an anode and the second electrode functions as a cathode. Upon termination of the first electrical signal, the anode and cathode each comprise a first accumulated energy. A second electrical signal is provided to the first and second electrodes, in which the second electrical signal includes at least a portion of the first accumulated energy.

Claims

1. A method of treating a medical condition in a patient using an implantable medical device, comprising:

coupling a first electrode to a first portion of a cranial nerve of the patient;

coupling a second electrode to a second portion of the cranial nerve of the patient;

providing a first electrical pulse to the first and second electrodes, wherein the first electrical pulse is provided in a first configuration in which the first electrode functions as an anode and the second electrode functions as a cathode, wherein upon termination of the first signal pulse, the anode and cathode each comprises an accumulated energy; and

providing a second electrical pulse to the first and second electrodes, the second electrical pulse comprising at least a portion of the accumulated energy.

2. The method of claim 1, further comprising providing a second configuration of the electrodes upon termination of the first electrical pulse, wherein in the second configuration, the first electrode functions as a cathode and the second electrode functions as an anode.

3. The method of claim 2, wherein the implantable medical device is capable of providing a changeable electrode polarity stimulation based upon the first and second configurations.

4. The method of claim 1, wherein providing the first electrical pulse comprises providing a controlled current pulse based upon at least one predetermined parameter.

5. The method of claim 1, wherein providing the first electrical pulse comprises providing a feedback controlled current pulse capable of adjusting the amount of energy used based upon said accumulated energy.

6. The method of claim 5, further comprising reducing an amount of energy provided by a power source associated with the implantable medical device in providing said second electrical pulse, in response to detecting said accumulated energy.

7. The method of claim 2, further comprising changing the configuration of the first and second electrodes from the second configuration to the first configuration upon termination of the second electrical pulse, and providing a third electrical pulse, wherein the third electrical pulse comprises at least a portion of an accumulated energy resulting from said step of providing a second electrical pulse.

8. A method of treating a medical condition in a patient using an implantable medical device, comprising:

providing a first electrical signal to a first electrode coupled to a first portion of a first electrically-stimulatable structure of the patient, and to a second electrode coupled to a second portion of a second electrically-stimulatable structure of the patient, wherein the first electrical signal is provided in a first polarity configuration in which the first electrode functions as an anode and the second electrode functions as a cathode, wherein the anode and cathode each comprises a first accumulated energy as a result of the first electrical signal;

providing a second polarity configuration of the electrodes upon termination of the first electrical signal, wherein in the second polarity configuration, the first electrode functions as a cathode and the second electrode function as an anode; and

providing a second electrical signal to the first and second electrodes in the second polarity configuration, the second electrical signal comprising at least a portion of the accumulated energy from the first electrical signal.

9. The method of claim 8, wherein the first electrically-stimulatable structure is selected from the group consisting of the brain, the spinal cord, the peripheral nerves, and the heart, and the second electrically-stimulatable structure is selected from the group consisting of the brain, the spinal cord, the peripheral nerves, and the heart.

10. The method of claim 9, wherein the cathode and anode each comprises a second accumulated energy as a result of the second electrical signal, further comprising changing the configuration of the first and second electrodes from the second polarity configuration to the first polarity configuration upon termination of the second electrical pulse, and providing a third electrical signal, wherein the third electrical signal comprises at least a portion of the second accumulated energy resulting from the second electrical signal.

11. The method of claim 9, wherein providing the first and second electrical signals comprises providing a feedback controlled current pulse capable of adjusting the amount of energy used based upon the first or second accumulated energy.

12. The method of claim 10, wherein the first electrical signal contains one pulse, the second electrical signal contains one pulse, and the third electrical signal contains one pulse.

13. The method of claim 10, wherein the first electrical signal contains a first number of pulses, the second electrical signal contains a second number of pulses, and the third electrical signal contains a third number of pulses, wherein the first number of pulses is not equal to the second number of pulses or the second number of pulses is not equal to the third number of pulses.

14. The method of claim 10, wherein the first electrical signal contains one or more bursts, the second electrical signal contains one or more bursts, and the third electrical signal contains one or more bursts.

15. The method of claim 10, wherein at least one of the first electrical signal, the second electrical signal, and the third electrical signal is characterized by having a number of pulses per microburst from 2 pulses to about 25 pulses, an interpulse interval from 2 msec to about 50 msec, an interburst period of at least 100 msec, and a microburst duration of less than about 1 sec.

16. The method of claim 9, wherein the medical condition is selected from the group consisting of depression, epilepsy, obesity, bulimia, traumatic brain injury, congestive heart failure, stroke, coma, fibromyalgia, addiction disorders, multiple sclerosis, haring disorder, Alzheimer'"'"'s disease, Parkinson'"'"'s disease, gastrointestinal disorders, pancreatic disorders, kidney disorders, and diabetes.

17. A method of treating a medical condition in a patient using an implantable medical device, comprising:

coupling a first electrode to a portion of a right cranial nerve of the patient;

coupling a second electrode to a portion of a left cranial nerve of the patient;

providing a first electrical signal to the first and second electrodes, wherein the first electrical pulse is provided in a first polarity configuration in which the first electrode functions as an anode and the second electrode functions as a cathode, wherein upon termination of the first electrical, the anode and cathode each comprises a first accumulated energy; and

providing a second polarity configuration of the electrodes upon termination of the first electrical signal, wherein in the second polarity configuration, the first electrode functions as a cathode and the second electrode function as an anode; and

providing a second electrical signal to the first and second electrodes in the second polarity configuration, the second electrical signal comprising at least a portion of the first accumulated energy.

18. The method of claim 17, wherein coupling the first electrode to a portion of a right cranial nerve comprises coupling the first electrode to a portion of the right vagus nerve of the patient and coupling the second electrode to a portion of a left cranial nerve comprises coupling the second electrode to a portion of the left vagus nerve of the patient.

19. The method of claim 17, wherein the cathode and anode each comprises a second accumulated energy as a result the second electrical signal, further comprising changing the configuration of the first and second electrodes from the second polarity configuration to the first polarity configuration upon termination of the second electrical pulse, and providing a third electrical signal, wherein the third electrical signal comprises at least a portion of the second accumulated energy resulting from the second electrical pulse.

20. An implantable medical device for treating a medical condition in a patient, comprising:

a controller capable of receiving data and controlling the operation of the implantable medical device by providing at least one control parameter;

a stimulation unit for generating and delivering, based upon the at least one control parameter, a first electrical signal to a first electrode electrically coupled to a first portion of a cranial nerve and to a second electrode electrically coupled to a second portion of a cranial nerve, wherein the first electrical signal is provided in a first polarity configuration in which the first electrode functions as an anode and the second electrode functions as a cathode, wherein upon termination of the first electrical signal, the anode and cathode each comprises a first accumulated energy resulting from the first electrical signal;

an electrode polarity reversal unit capable of changing the polarity configuration of the first and second electrodes from the first polarity configuration to a second polarity configuration in which the first electrode functions as a cathode and the second electrode function as an anode; and

wherein the stimulation unit also provides a second electrical signal to the first and second electrodes in the second polarity configuration, wherein the second electrical signal comprises at least a portion of the first accumulated energy.

21. The implantable medical device of claim 20, wherein the electrode polarity reversal unit comprises:

an electrode configuration switching unit comprising a switching controller; and

a plurality of switches, wherein the switching controller is capable of controlling an operation of the switches to change the polarity configuration of the first and second electrodes from the first polarity configuration to the second polarity configuration, and from the second polarity configuration to the first polarity configuration.

22. The implantable medical device of claim 21, wherein the cathode and anode each comprises a second accumulated energy upon termination of the second electrical signal;

wherein the electrode polarity reversal unit changes the polarity configuration of the first and second electrodes from the second polarity configuration to the first polarity configuration upon termination of the second electrical signal; and

wherein the stimulation unit provides a third electrical signal to the first and second electrodes, wherein the third electrical signal comprises at least a portion of the second accumulated energy.

23. The implantable medical device of claim 20, further comprising a first capacitor in series with said first electrode and a second capacitor in series with the second electrode, the first and second capacitors to store charge as a result of the first and second electrical signals.

24. A computer readable program storage device encoded with instructions that, when executed by a computer, performs a method of treating a medical condition in a patient using an implantable medical device, comprising:

providing a first electrical signal to a first electrode coupled to a first portion of a cranial nerve of the patient, and to a second electrode coupled to a second portion of a cranial nerve of the patient, wherein the first and second electrodes are provided in a first polarity configuration in which the first electrode functions as an anode and the second electrode functions as a cathode, wherein upon termination of the first electrical signal, the anode and cathode each comprises a first accumulated energy;

providing a second polarity configuration of the electrodes upon termination of the first electrical signal, wherein in the second polarity configuration, the first electrode functions as a cathode and the second electrode function as an anode; and

providing a second electrical signal to the first and second electrodes in the second polarity configuration, the second electrical signal comprising at least a portion of the first accumulated energy.

25. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 24, wherein upon termination of the second electrical signal the cathode and anode each comprises a second accumulated energy, further comprising changing the polarity configuration of the first and second electrodes from the second polarity configuration to the first polarity configuration upon termination of the second electrical pulse, and providing a third electrical signal, wherein the third electrical signal comprises at least a portion of the second accumulated energy.