Medical devices and methods for delivery of current-based electrical stimulation therapy

Patent metadata

Field	Value
Publication number	US-9987493-B2
Application number	US-57903609-A
Country	US
Kind code	B2
Filing date	Oct 14, 2009
Priority date	Oct 28, 2008
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A medical electrical stimulator provides selective control of stimulation via a combination of two or more electrodes coupled to respective regulated current paths and one or more electrodes coupled to unregulated current paths. Constant current sources may control the current that is sourced or sunk via respective regulated current paths. An unregulated current path may sink or source current to and from an unregulated voltage source that serves as a reference voltage. Unregulated electrodes may function as unregulated anodes to source current from a reference voltage or unregulated cathodes to sink current to a reference voltage.

First claim

The invention claimed is:

1. A device for delivering electrical nerve, muscle, or brain tissue stimulation therapy to a patient, the device comprising:
a plurality of implantable electrodes;
a regulated current source path;
a regulated current sink path;
an unregulated current path; and
a stimulation generator comprising a stimulation controller configured to couple a first electrode of the plurality of electrodes to a regulated current source of the regulated current source path to deliver electrical stimulation current to the patient for delivering the electrical nerve, muscle, or brain tissue stimulation therapy to the patient, couple a second electrode of the plurality of electrodes to a regulated current sink of the regulated current sink path to deliver the electrical stimulation current to the patient for delivering the electrical nerve, muscle, or brain tissue stimulation therapy to the patient, and couple a third electrode of the plurality of electrodes to a reference voltage of the unregulated current path via a switch to deliver the electrical stimulation current to the patient for delivering the electrical nerve, muscle, or brain tissue stimulation therapy to the patient,
wherein the reference voltage comprises a low reference voltage when the unregulated current path sinks current and a high reference voltage when the unregulated current path sources current, and
wherein the stimulation generator is configured to deliver the electrical nerve, muscle, or brain tissue stimulation therapy to the patient by delivering the electrical stimulation current to the patient via a combination of the electrodes that includes the first electrode, the second electrode, and the third electrode.

2. The device of claim 1 , further comprising one or more implantable leads, wherein each of the electrodes is located on a respective one of the one or more leads.

3. The device of claim 1 , wherein the stimulation generator is further configured to:
deliver a first amount of the electrical stimulation current via the regulated current source path;
deliver a second amount of the electrical stimulation current via the regulated current sink path; and
deliver a third amount of the electrical stimulation current via the unregulated current path, the third amount of the electrical stimulation current being approximately equal to a difference between the first and second amounts of the electrical stimulation current.

4. The device of claim 3 , wherein:
the regulated current source sources the first amount of the electrical stimulation current via the regulated current source path,
the regulated current sink sinks the second amount of the electrical stimulation current via the regulated current sink path,
the second amount of the electrical stimulation current is less than the first amount of the electrical stimulation current,
the unregulated current path sinks the third amount of the electrical stimulation current to the reference voltage, and
the third amount of the electrical stimulation current is greater than the second amount of the electrical stimulation current.

5. The device of claim 3 , wherein:
the regulated current source sources the first amount of the electrical stimulation current via the regulated current source path,
the regulated current sink sinks the second amount of the electrical stimulation current via the regulated current sink path,
the second amount of the electrical stimulation current is less than the first amount of the electrical stimulation current,
the unregulated current path sinks the third amount of the electrical stimulation current to the reference voltage, and
the reference voltage required to produce the unregulated sink current is less than another voltage required to produce the regulated sink current.

6. The device of claim 3 , wherein:
the regulated current sink sinks the second amount of the electrical stimulation current via the regulated current sink path,
the regulated current source sources the first amount of the electrical stimulation current via the regulated current source path,
the first amount of the electrical stimulation current is less than the second amount of the electrical stimulation current,
the unregulated current path sources the third amount of the electrical stimulation current from the reference voltage, and
the third amount of the electrical stimulation current is greater than the first amount of the electrical stimulation current.

7. The device of claim 3 , wherein:
the regulated current sink sinks the second amount of the electrical stimulation current via the regulated current sink path,
the regulated current source sources the first amount of the electrical stimulation current via the regulated current source path,
the first amount of the electrical stimulation current is less than the second amount of the electrical stimulation current,
the unregulated current path sources the third amount of the electrical stimulation current from the reference voltage, and
the reference voltage required to produce the third amount of the electrical stimulation current is greater than another voltage required to produce the first amount of the electrical stimulation current.

8. The device of claim 3 , wherein the regulated current source path comprises a plurality of parallel regulated current source paths, the regulated current sink path comprises a plurality of parallel regulated current sink paths, and the unregulated current path comprises a plurality of parallel unregulated current paths.

9. The device of claim 1 ,
wherein the unregulated current path is a first unregulated current path,
wherein the device further comprises a second unregulated current path,
wherein the stimulation controller is further configured to couple a fourth electrode of the plurality of electrodes to the second unregulated current path, and
wherein the third and fourth electrodes are positioned between the first and second electrodes along the length of one or more implantable leads.

10. The device of claim 1 ,
wherein the unregulated current path is a first unregulated current path,
wherein the device further comprises a second unregulated current path,
wherein the stimulation controller is further configured to couple a fourth electrode of the plurality of electrodes to the second unregulated current path, and
wherein the first and second electrodes are positioned between the third and fourth electrodes along the length of one or more implantable leads.

11. The device of claim 1 , wherein the stimulation controller is configured to couple a fourth electrode of the plurality of electrodes to a regulated current path.

12. The device of claim 1 ,
wherein the regulated current source is one of a plurality of regulated current sources and the regulated current sink is one of a plurality of regulated current sinks, and
wherein at least one of the electrodes of the plurality of electrodes is configurable by the stimulation controller to be electrically coupled to one of the regulated current sources, electrically coupled to one of the regulated current sinks, electrically coupled to the high reference voltage, or electrically coupled to the low reference voltage.

13. The device of claim 1 ,
wherein a current level sourced or sunk by the unregulated current source path varies with different impedance load conditions.

14. The device of claim 1 ,
wherein the regulated current source is one of a plurality of regulated current sources and the regulated current sink is one of a plurality of regulated current sinks,
wherein at least one of the plurality of electrode

Assignees

• Torgerson Nathan A
• Michaels Matthew J
• Medtronic Inc

Inventors

• Torgerson Nathan A
• Michaels Matthew J

Classifications

• A61N1/36082

  Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease · CPC title

• A61N1/36185 Primary

  Selection of the electrode configuration · CPC title

• A61N1/36125

  Details of circuitry or electric components · CPC title