FIRING PATTERNS FOR DEEP BRAIN TRANSCRANIAL MAGNETIC STIMULATION

• US 20100256438A1
• Filed: 08/20/2008
• Published: 10/07/2010
• Est. Priority Date: 08/20/2007
• Status: Active Grant

• Current Assignee: Brainsway, Ltd.
• Original Assignee: Cervel (Assignment For The Benefit Of Creditors), LLC
• Inventors: Schneider, M. Bret, Mishelevich, David J.
• Granted Patent: US 8,956,273 B2
• Time in Patent Office: Days
• US Class Current: 600/13
• 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

Methods, devices and systems for Transcranial Magnetic Stimulation (TMS) are provided for synchronous, asynchronous, or independent triggering the firing multiple of electromagnets from either a single power source or multiple energy sources. These methods are particularly useful for stimulation of deep (e.g., sub-cortical) brain regions, or for stimulation of multiple brain regions, since controlled magnetic pulses reaching the deep target location may combine to form a patterned pulse train that activates the desired volume of target tissue. Furthermore, the methods, devices and systems described herein may be used to control the rate of firing of action potentials in one or more brain regions, such as slow or fast rate rTMS. For example, described herein are multiple electromagnetic stimulation sources, each of which are activated independently to create a cumulative effect at the intersections of the electromagnetic stimulation trajectories, typically by means of a computerized calculation.

Claims

1. A Transcranial Magnetic Stimulation (TMS) method for stimulating neuronal tissue deep within a subject'"'"'s brain by firing a plurality of electromagnets located at different locations around the subject'"'"'s head, the method comprising:

firing a first electromagnet at a first duration, rate and power to emit an electromagnetic pulse along a first pathway through the subject'"'"'s brain;

firing a second electromagnet at a second duration, rate and power to emit an electromagnetic pulse along a second pathway through the subject'"'"'s brain;

triggering stimulation in a target deep region of the subject'"'"'s brain located in the intersection of the first and second pathways by temporally and spatially summing the effects of the electromagnetic pulses emitted by the first and second electromagnets on the target deep region of the subject'"'"'s brain.

2. The method of claim 1, further comprising:

determining the first duration rate and power for firing the first electromagnet; and

determining the second duration rate and power for firing the second electromagnet, wherein the first and second duration rate and power are determined based on an attenuation factor and the distance to the target deep region in the subject'"'"'s brain from the first and second electromagnet.

3. The method of claim 1, further wherein the step of firing the first electromagnet comprises firing the first electromagnet at a first duration, rate and power that does not trigger stimulation of neural tissue located more superficially to the target deep tissue region.

4. The method of claim 1, further wherein the step of firing the second electromagnet comprises firing the second electromagnet at a second duration, rate and power that does not trigger stimulation of neural tissue located more superficially to the target deep tissue region.

5. The method of claim 1, wherein the first duration, rate and power are different from the second duration, rate and power.

6. The method of claim 1, wherein the step of firing the first electromagnet comprises firing the first electromagnet from a stationary electromagnet that is not configured to move during a TMS treatment.

7. The method of claim 1, wherein the step of firing the first electromagnet comprises firing the first electromagnet from a movable electromagnet that is configured to move during a TMS treatment.

8. The method of claim 1, further comprising firing a third electromagnet at a third duration, rate and power to emit an electromagnetic pulse along a third pathway through the subject'"'"'s brain, wherein the third pathway intersects with the first, second and third pathway at the target deep region of the subject'"'"'s brain.

9. The method of claim 8, wherein the step of triggering stimulation in the target deep region of the subject'"'"'s brain further comprises temporally and spatially summing the effects of the electromagnetic pulses emitted by the first, second, and third electromagnets on the target deep region of the subject'"'"'s brain.

10. The method of claim 1, further comprising triggering stimulation in the target deep region of the subject'"'"'s brain at a predetermined rate by firing bursts of electromagnetic pulses from the first and second electromagnets that sum to trigger stimulation within the target deep region, wherein the bursts of pulses are separated by a waiting period during which electromagnetic pulses from the first and second electromagnets do not sum to trigger stimulation in the target deep region.

11. The method of claim 1, wherein the steps of firing the first electromagnet and firing the second electromagnet comprise powering the first electromagnet and the second electromagnet from a first power source.

12. The method of claim 1, wherein the steps of firing the first electromagnet and firing the second electromagnet comprise powering the first electromagnet and the second electromagnet from different power sources.

13. A Transcranial Magnetic Stimulation (TMS) method for stimulating neuronal tissue deep within a subject'"'"'s brain by firing a plurality of electromagnets located at different locations around the subject'"'"'s head, the method comprising:

selecting deep brain target;

determining treatment objectives for the deep brain target and a plurality of collateral targets, wherein the collateral targets correspond to brain structures between the deep brain target and each of the electromagnets;

generating a treatment strategy configured to achieve the treatment objectives, wherein the treatment strategy comprises a stimulation pattern of firing of the electromagnets, and a set of individual control instructions for firing each of the electromagnets in the stimulation pattern; and

applying the treatment strategy to the plurality of electromagnets.

14. The method of claim 13, wherein the step of determining treatment objectives for the deep brain target and the plurality of collateral targets includes referring to a database of suggested treatment objectives based on the target region.

15. The method of claim 13, wherein the step of determining the treatment objectives includes setting the collateral treatment objectives to up-regulation, down-regulation or non-regulation.

16. The method of claim 13, wherein the step of generating a treatment strategy comprises generating a plurality of candidate treatment strategies, simulating each candidate treatment strategy, scoring each simulated candidate strategy based on achievement of the treatment objectives, and selecting the treatment strategy from the scored candidate strategies.

17. The method of claim 13, wherein the step of applying the treatment strategy comprises controlling each electromagnet to execute its individual control instructions.

18. The method of claim 13, further comprising adjusting the position of the electromagnets to focus on the deep brain target.

19. A Transcranial Magnetic Stimulation (TMS) method for stimulating neuronal tissue deep within a subject'"'"'s brain by firing a plurality of electromagnets located at different locations around the subject'"'"'s head, the method comprising:

firing a first electromagnet at a first stimulation pattern so that a plurality of electromagnetic pulses are emitted along a first pathway;

firing a second electromagnet at a second stimulation pattern so that a plurality of electromagnetic pulses are emitted along a second pathway;

triggering a pattern of stimulation at a target deep region of the subject'"'"'s brain located in the intersection of the first and second pathways by temporally summing the effects of the electromagnetic pulses emitted by the first and second electromagnets on the target deep region of the subject'"'"'s brain.

20. A Transcranial Magnetic Stimulation (TMS) system for stimulating neuronal tissue deep within a subject'"'"'s brain, the system including:

a plurality of electromagnets configured to be arranged around the subject'"'"'s head;

a plurality of drivers, wherein each driver is configured to couple with one of the electromagnets to gate excitation of the electromagnet;

a stimulation controller configured to determine firing patterns for each of the electromagnets of the plurality of electromagnets so as to trigger stimulation at a target deep region of the subject'"'"'s brain, wherein the firing patterns are determined by estimating the temporal and spatial summation of the effect of the firing of the plurality of electromagnets at the target deep tissue region.

21. The system of claim 20, further comprising a distributor configured to communicate with the stimulation controller and each of the drivers of the plurality of drivers, wherein the distributor is further configured to command the drivers based on the control of the stimulation controller.

22. The system of claim 20, further comprising a power source configured to supply power to the plurality of electromagnets.

23. The system of claim 20, further comprising a plurality of power sources configured to supply power to the electromagnets.

24. The system of claim 20, wherein the stimulation controller is configured to receive input indicating the location of the target deep tissue region relative to the plurality of electromagnets.

25. A transcranial Magnetic Stimulation (TMS) system for stimulating neuronal tissue deep within a subject'"'"'s brain, the system including:

a plurality of electromagnets configured to be arranged around the subject'"'"'s head;

a plurality of drivers, wherein each driver is configured to couple with one of the electromagnets to gate excitation of the electromagnet;

a distributor configured to couple with the drivers, wherein the distributor is further configured to command the drivers;

a stimulation controller configured to communicate with the distributors and to determine firing patterns for each of the electromagnets so as to trigger stimulation at a target deep region of the subject'"'"'s brain, wherein the firing patterns are determined based on estimates of the temporal and spatial summation of the effect of the firing of the plurality of electromagnets at the target deep tissue region.