Robotic apparatus for targeting and producing deep, focused transcranial magnetic stimulation

• US 7,520,848 B2
• Filed: 04/09/2004
• Issued: 04/21/2009
• Est. Priority Date: 04/09/2004
• Status: Active Grant

• Current Assignee: US Department of Veterans Affairs (Government of the United States of America), Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Mishelevich, David J., Schneider, M. Bret
• Primary Examiner(s): Gilbert; Samuel G
• Application Number:
  US10/821,807
• Publication Number:
  US 20050228209A1
• Time in Patent Office: 1,838 Days
• Field of Search: 600 9- 15, 128/897, 128/898
• US Class Current: 600/13
• CPC Class Codes: A61B 5/246 using evoked responses
• CPC Class Codes: A61N 2/006 for magnetic stimulation of nerve tissue
• CPC Class Codes: A61N 2/02 using magnetic fields produced by coils, including single turn loops or electromagnets A61N2/12 takes precedence

Abstract

Techniques for applying electromagnetic energy to deep, targeted areas without overwhelming other areas are provided. One or more coils are moved relative to a target area and magnetic fields are applied to the target from multiple coil locations. As a result, the aggregate electromagetic energy applied to the target over time is greater than surrounding areas. Additionally, a model for testing and treatment planning is provided.

Claims

1. A method of applying electromagnetic energy to a target, comprising:

moving a coil relative to the target; and

applying current to the coil from a plurality of locations to direct magnetic fields to the target and magnetically stimulate the target, wherein the current is applied to the coil at a sufficiently rapid frequency prevent re-polarization of the target as the coil is moved, such that the magnetic stimulation of the target is higher at the target than at a region interposed between the target and the coil.

2. The method of claim 1, further comprising adjusting the current to the coil at each location so that the magnetic field at the target is constant.

3. The method of claim 2, wherein the current is adjusted by the inverse of the square of the distance between the coil and the target.

4. The method of claim 1, further comprising selectively not applying current to the coil at a location where directing a magnetic field at the target would expose an area interposed between the target and the coil to undesirable magnetic field energy.

5. The method of claim 1, further comprising selecting a duration for applying the current depending on a location of the coil.

6. The method of claim 1, further comprising selecting an inter-pulse interval for applying the current depending on a location of the coil.

7. The method of claim 1, further comprising selecting an intra-pulse frequency for applying the current depending on a location of the coil.

8. The method of claim 1, further comprising selecting a speed of movement of the coil.

9. The method of claim 1, further comprising a plurality of coils.

10. The method of claim 1, wherein the coil is a transcranial magnetic stimulation (TMS) coil.

11. The method of claim 1, further comprising the step of aiming the coil at the target, wherein the target is a sub-cortical brain region.

12. A method of applying electromagnetic energy to a target, comprising:

magnetically stimulating a neuronal target from a first location by applying current to a coil;

moving the to a second location relative to the target;

continuing the magnetic stimulation of the neuronal target from the second location by applying current to the coil, wherein the magnetic stimulation is greater at the target than the magnetic stimulation at a region interposed between the target at the coil;

wherein the current applied to the coil at the first and second locations is applied at a frequency sufficient to prevent re-polarization of the target as the coil is moved.

13. The method of claim 12, further comprising adjusting the current to the coil at each location so that the magnetic field at the target is constant.

14. The method of claim 13, wherein the current is adjusted by the inverse of the square of the distance between the coil and the target.

15. The method of claim 12, further comprising selectively not applying current to the coil at a location where directing a magnetic field at the target would expose an area interposed between the target and the coil to undesirable magnetic field energy.

16. The method of claim 12, further comprising selecting a duration for applying the current depending on a location of the coil.

17. The method of claim 12, further comprising selecting an inter-pulse interval for applying the current depending on a location of the coil.

18. The method of claim 12, further comprising selecting an intra-pulse frequency for applying the current depending on a location of the coil.

19. The method of claim 12, further comprising selecting a speed of movement of the coil.

20. The method of claim 12, further comprising a plurality of coils.

21. The method of claim 12, wherein the coil is a transcranial magnetic stimulation (TMS) coil.

22. The method of claim 12, further comprising the step of aiming the coil at the target, wherein the target is a sub-cortical brain region.

23. A method of applying electromagnetic energy to a target brain region, comprising:

magnetically stimulating a target brain region by applying current to a coil from a first location;

moving coil relative to the target brain region; and

continuing to magnetically stimulate the target brain region by applying current to the coil when the coil is at a second location to direct magnetic fields to the target brain region, wherein the magnetic stimulation is applied at a frequency sufficient to prevent re-polarization of the target brain region as the coil is moved, such that the magnetic stimulation over time at the target brain region sums and is higher at the target brain region than at brain regions interposed between the target brain region and the coil.

24. The method of claim 23, wherein the step of magnetically stimulating a brain region comprises magnetically stimulating a deep brain region.

25. The method of claim 24, wherein the step of magnetically stimulating a deep brain region comprises magnetically stimulating a sub-cortical brain region.