Deep brain stimulation implant with microcoil array

• US 8,944,985 B2
• Filed: 04/03/2009
• Issued: 02/03/2015
• Est. Priority Date: 04/03/2008
• Status: Active Grant

• Current Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Original Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Inventors: Bonmassar, Giorgio, Hamalainen, Matti S., Rosen, Bruce
• Primary Examiner(s): Marmor, II, Charles A
• Assistant Examiner(s): Dorna, Carrie R
• Application Number:
  US12/418,324
• Publication Number:
  US 20090254146A1
• Time in Patent Office: 2,132 Days
• Field of Search: 600 9- 15, 600/372, 600/373, 600/377, 600/378, 600/393, 606 32- 52, 607/1, 607/41, 607/45, 607/46, 607115-118, 607/148
• US Class Current: 600/13
• CPC Class Codes: A61N 1/0531 Brain cortex electrodes
• CPC Class Codes: A61N 1/0534 Electrodes for deep brain stimulation
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/40 Applying electric fields by inductive or capacitive coupling microwave apparatus A61N5/00; Applying radio-frequency signals
• CPC Class Codes: A61N 2/004 specially adapted for a specific therapy
• 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

An implant for deep brain stimulation (DBS) has an array of electromagnetic microcoils dispersed over the length of the implant. The microcoils produce magnetic fields that are directed into, and induce current in, the adjacent brain tissue. The microcoils may be selectively operated to direct and focus electrical stimulation to targeted areas of the brain. The implant is useful in studying or treating neurophysiological conditions associated with the deep regions of the brain such as Parkinson'"'"'s disease, drug addiction, and depression.

Claims

1. A device for stimulating biological tissue, the device comprising:

an insertable implant extending along a longitudinal axis from a proximal portion to a distal portion;

a plurality of electrical conductors extending along the longitudinal axis of the implant;

a plurality of microcoils proximate to the distal portion of the implant, each of the microcoils being coupled to at least one of the electrical conductors;

an electrically isolating barrier completely covering the plurality of microcoils; and

a coupling configured to connect the microcoils to a power source through the plurality of electrical conductors to drive the plurality of microcoils to produce magnetic fields suitable for performing deep brain stimulation (DBS).

2. The device of claim 1, wherein the distal portion of the implant is at least partially cylindrically shaped and the microcoils are spaced about the distal portion of the implant.

3. The device of claim 2, wherein the plurality of microcoils are substantially evenly spaced in an array pattern.

4. The device of claim 1, wherein the microcoils are uniformly spaced apart about the distal portion.

5. The device of claim 1, wherein each of the plurality of microcoils include at least three turns.

6. The implant of claim 1, wherein the proximal portion is configured for coupling the implant to an electrical pulse generator.

7. The device of claim 1, further comprising a stimulator configured to control a delivery of power from the power source to the plurality of microcoils to deliver an electrical current to a selected combination of the plurality of microcoils, in a preselected pattern to perform DBS.

8. The device of claim 1, wherein the implant comprises:

a base;

a ground layer covering the base;

a dielectric layer covering the ground layer;

a biocompatible coating covering the dielectric layer;

wherein the plurality of microcoils and plurality of electrical conductors are at least one of embedded in and disposed on a radially outward surface of the dielectric layer.

9. The implant of claim 8, wherein the biocompatible coating forms at least a portion of the electrically isolating barrier covering the plurality of microcoils.

10. The implant of claim 9, wherein the biocompatible coating is parylene.

11. The implant of claim 8, wherein the base is a glass fiber and the ground layer is gold.

12. The implant of claim 1, wherein the plurality of microcoils include at least one of three-turn coils and seven-turn coils.

13. The device of claim 1, wherein each of the plurality of microcoils comprises copper.

14. A brain stimulation device comprising:

a power source configured to produce a plurality of electric pulses;

an insertable implant extending along a longitudinal axis from a proximal portion to a distal portion;

a plurality of electrical conductors extending along the longitudinal axis of the implant;

a plurality of microcoils proximate to the distal portion of the implant, each of the microcoils being coupled to at least one of the electrical conductors;

an electrically isolating barrier completely covering the plurality of microcoils; and

a coupling configured to connect the microcoils to a power source through the plurality of electrical conductors to drive the plurality of microcoils to produce magnetic fields suitable for performing deep brain stimulation (DBS).

15. The brain stimulation device of claim 14, wherein the electrically isolating barrier includes a biocompatible coating extending over the plurality of microcoils.

16. The brain stimulation device of claim 15, wherein the plurality of microcoils are formed of a gold trace and the biocompatible coating includes parylene.

17. The brain stimulation device of claim 16, wherein the plurality of microcoils are arranged in an array about the implant.

18. The brain stimulation device of claim 15, wherein at least a portion of the plurality of microcoils are disposed in a first row at a first axial position and a second row at a second axial position.

19. The brain stimulation device of claim 15, further comprising a controller configured to selectively control the delivery of the plurality of electrical pulses to the plurality of microcoils to one of focus and shape the magnetic field produced by the plurality of microcoils.

20. A deep brain stimulation system comprising:

an implant including;

a base;

an electrical ground layer covering the base;

an electrically insulating layer covering the ground layer;

a plurality of planar microcoils operable to produce a magnetic field proximate thereto; and

a biocompatible dielectric coating covering at least one of the plurality of microcoils and the electrically insulating layer; and

a power source configured to power at least one of the plurality of microcoils to produce a magnetic field configured to induce an electrical current in tissue adjacent to the at least one microcoil to perform DBS,

wherein the implant is configured such that there is no direct contact between the plurality of planar microcoils and brain tissue.

21. The system of claim 20, wherein the plurality of microcoils are spaced apart in an array over a distal portion of the implant.

22. The system of claim 20, wherein each of the plurality of planar microcoils comprises copper.