Selective dorsal column stimulation in SCS, using conditioning pulses

• US 20040044378A1
• Filed: 03/20/2003
• Published: 03/04/2004
• Est. Priority Date: 04/30/1998
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Holsheimer, Jan
• Granted Patent: US 6,850,802 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61N 1/3604 for correcting spinal deformities, e.g. scoliosis

Abstract

A system and method is described for preferentially stimulating dorsal column fibers while avoiding stimulation of dorsal root fibers. The invention applies hyperpolarizing pre-pulses and depolarizing pre-pulses to neural tissue, such as spinal cord tissue, through a lead placed over the spinal cord having the electrodes arranged on a line approximately transverse to the axis of the spine. To increase the threshold needed to stimulate dorsal root fibers, the anodal pulse given by each lateral contact of the electrodes has to be preceded by a depolarizing pre-pulse and simultaneously, the central electrode contact gives a hyperpolarizing pre-pulse, thereby reducing the stimulation threshold for the dorsal column fibers to subsequent depolarizing pulses.

Claims

1. A method of electrically stimulating neural tissue of the brain comprising the steps of:

providing a source of electrical pulses;

providing a first electrode;

providing an electrical return path;

connecting the first electrode to the source of electrical pulses;

placing the first electrode in tissue of a patient'"'"'s brain;

applying a hyperpolarizing electrical pre-pulse to the tissue through the first electrode and source of electrical pulses wherein the tissue is more susceptible to subsequent electric stimulation;

applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

2. The method of claim 1 further comprising the step of applying a depolarizing electrical pulse to the tissue through the first electrode subsequent to the step of applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

3. The method of claim 1 wherein the step of providing an electrical return path includes the step of providing an electrical return path that includes a second electrode.

4. The method of claim 1 wherein the step of providing an electrical return path includes the step of providing an electrical return path that includes the source of electrical pulses.

5. The method of claim 1 wherein the step of providing a first electrode includes the step of providing a second electrode spaced from the first electrode and further comprising the step of connecting the second electrode to the source of electrical pulses.

6. The method of claim 5 further comprising the step of:

applying a depolarizing electrical pre-pulse to the tissue through the second electrode and source of electrical pulses wherein the tissue near the second electrode is less susceptible to subsequent electric stimulation.

7. The method of claim 6 wherein the step of providing a first electrode and a second electrode spaced from the first electrode includes the step of providing a third electrode spaced from the first and second electrodes and further comprising the step of connecting the third electrode to the source of electrical pulses.

8. The method of claim 7 further comprising the step of:

applying a depolarizing electrical pre-pulse to the tissue through the third electrode and source of electrical pulses wherein the tissue near the third electrode is less susceptible to subsequent electric stimulation.

9. The method of claim 7 further comprising the step of:

applying a hyperpolarizing electrical pre-pulse to the tissue through the third electrode and source of electrical pulses wherein the tissue near the third electrode is more susceptible to subsequent electric stimulation.

10. The method of claim 1 further comprising the step of implanting the source of electrical pulses within the patient'"'"'s body.

11. A method of electrically stimulating neural tissue of the brain comprising the steps of:

providing a source of electrical pulses;

providing a first electrode;

providing an electrical return path;

connecting the first electrode to the source of electrical pulses;

placing the first electrode in tissue of a patient'"'"'s brain;

applying a depolarizing electrical pre-pulse to the tissue through the first electrode and source of electrical pulses wherein the tissue is less susceptible to subsequent electric stimulations

applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

12. The method of claim 11 further comprising the step of applying a subsequent hyperpolarizing electrical pulse to the tissue through the first electrode wherein the tissue is more susceptible to subsequent electric stimulation.

13. A method of electrically stimulating neural tissue of the brain comprising the steps of:

providing a source of electrical pulses;

providing a first electrode;

providing an electrical return path;

connecting the first electrode to the source of electrical pulses;

placing the first electrode on the surface of a patient'"'"'s brain;

applying a hyperpolarizing electrical pre-pulse to the tissue through the first electrode and source of electrical pulses wherein the tissue is more susceptible to subsequent electric stimulation;

applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

14. The method of claim 13 wherein the step of providing an electrical return path includes the step of providing an electrical return path that includes a second electrode.

15. The method of claim 13 wherein the step of providing an electrical return path includes the step of providing an electrical return path that includes the source of electrical pulses.

16. The method of claim 13 wherein the step of providing a first electrode includes the step of providing a second electrode spaced from the first electrode and further comprising the step of connecting the second electrode to the source of electrical pulses.

17. The method of claim 16 further comprising the step of:

applying a depolarizing electrical pre-pulse to the tissue through the second electrode and source of electrical pulses wherein the tissue near the second electrode is less susceptible to subsequent electric stimulation.

18. The method of claim 17 wherein the step of providing a first electrode and a second electrode spaced from the first electrode includes the step of providing a third electrode spaced from the first and second electrodes and further comprising the step of connecting the third electrode to the source of electrical pulses.

19. The method of claim 18 further comprising the step of:

applying a depolarizing electrical pre-pulse to the tissue through the third electrode and source of electrical pulses wherein the tissue near the third electrode is less susceptible to subsequent electric stimulation.

20. The method of claim 18 further comprising the step of:

applying a hyperpolarizing electrical pre-pulse to the tissue through the third electrode and source of electrical pulses wherein the tissue near the third electrode is more susceptible to subsequent electric stimulation.

21. The method of claim 13 further comprising the step of implanting the source of electrical pulses within the patient'"'"'s body.

22. A method of electrically stimulating neural tissue of the brain comprising the steps of:

providing a source of electrical pulses;

providing a first electrode;

providing an electrical return path;

connecting the first electrode to the source of electrical pulses;

placing the first electrode on the surface of a patient'"'"'s brain;

applying a depolarizing electrical pre-pulse to the tissue through the first electrode and source of electrical pulses wherein the tissue is less susceptible to subsequent electric stimulation;

applying a subsequent [hyperpolarizing] depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

23. The method of claim 22 further comprising the step of applying a hyperpolarizing electrical pulse to the tissue through the first electrode subsequent to the step of applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue.

24. A method of electrically stimulating neural tissue of the brain comprising the steps of:

providing a source of electrical pulses;

providing a first electrode, a second electrode spaced from the first electrode and a third electrode spaced from the first electrode opposite the second electrode so that the first electrode is generally between the second and third electrodes;

providing an electrical return path;

connecting the first, second and third electrodes to the source of electrical pulses;

placing the first, second and third electrodes within a patient'"'"'s body in a patient'"'"'s brain;

applying a hyperpolarizing electrical pre-pulse to the tissue through the first electrode and source of electrical pulses wherein the tissue is more susceptible to subsequent electric stimulation;

applying a depolarizing electrical pre-pulse to the tissue through the second and third electrodes and source of electrical pulses wherein the tissue near the second and third electrodes is less susceptible to subsequent electric stimulation;

applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue near the first electrode.

25. The method of claim 24 further comprising the step of applying a depolarizing electrical pulse to the tissue through the first electrode subsequent to the step of applying a subsequent depolarizing electrical pulse to the tissue through the first electrode wherein an action potential is generated in the tissue near the first electrode.

26. The method of claim 24 further comprising the step of implanting the source of electrical pulses within the patient'"'"'s body.