Conformable actively multiplexed high-density surface electrode array for brain interfacing

• US 10,349,860 B2
• Filed: 11/04/2014
• Issued: 07/16/2019
• Est. Priority Date: 06/03/2011
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Rogers, John A., Kim, Dae-Hyeong, Litt, Brian, Viventi, Jonathan
• Primary Examiner(s): Stoklosa, Joseph A
• Assistant Examiner(s): Antiskay, Brian M
• Application Number:
  US14/532,687
• Publication Number:
  US 20150080695A1
• Time in Patent Office: 1,715 Days
• Field of Search: 600378, 600544-545, 607115-116
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/0036 including treatment, e.g., using an implantable medical device, ablating, ventilating
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/291 for electroencephalography [EEG]
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: A61B 5/6868 Brain
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7267 involving training the classification device
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61M 5/20 Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically A61M5/142 , A61M5/46 take precedence; hypodermic projectiles F42B12/54
• CPC Class Codes: A61M 5/31 Details
• CPC Class Codes: A61N 1/0529 Electrodes for brain stimulation
• CPC Class Codes: A61N 1/0531 Brain cortex electrodes
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/36025 for treating a mental or cerebral condition
• CPC Class Codes: A61N 2005/063 comprising light transmitting means, e.g. optical fibres
• CPC Class Codes: A61N 5/0601 Apparatus for use inside the body
• CPC Class Codes: G16H 50/70 : for mining of medical data, e.g. analysing previous cases of other patients

Abstract

Provided are methods and devices for interfacing with brain tissue, specifically for monitoring and/or actuation of spatio-temporal electrical waveforms. The device is conformable having a high electrode density and high spatial and temporal resolution. A conformable substrate supports a conformable electronic circuit and a barrier layer. Electrodes are positioned to provide electrical contact with a brain tissue. A controller monitors or actuates the electrodes, thereby interfacing with the brain tissue. In an aspect, methods are provided to monitor or actuate spatio-temporal electrical waveforms over large brain surface areas by any of the devices disclosed herein.

Claims

1. A device for spatio-temporally electrically interfacing with a brain in a biological environment, the device comprising:

a conformable substrate;

a conformable electronic circuit comprising a deformable array of electrodes in electrical communication with a plurality of deformable electrical interconnects, the deformable array of electrodes supported by the conformable substrate;

a barrier layer encapsulating at least a portion of the deformable electrical interconnects, wherein the conformable substrate, conformable electronic circuit and the barrier layer provide a net bending stiffness of the device low enough that the device establishes conformal contact with brain tissue in the biological environment; and

a controller connected to the conformable electrical circuit to monitor or actuate a spatio-temporal profile over a surface of the brain in electrical contact with the plurality of electrodes, wherein the controller is configured to;

detect an electric potential of a plurality of individual brain surface locations beneath each electrode of the array of electrodes at a plurality of different time points;

encode the detected electric potential to obtain an encoded spatio-temporal brain waveform;

analyze the encoded spatio-temporal brain waveform to identify an abnormal spatio-temporal brain waveform; and

actuate electrical activity over the brain surface with an output spatio-temporal profile from the deformable array of electrodes to disrupt or terminate the abnormal spatio-temporal brain waveform.

2. The device of claim 1, wherein each electrode is electrically connected to a pair of matched transistors, wherein the matched transistors comprise a multiplexing transistor and a buffer transistor.

3. The device of claim 2, wherein each pair of matched transistors are electrically connected to a common constant current source and a current mirror.

4. The device of claim 2, wherein the matched transistors are flexible and comprise single-crystal silicon.

5. The device of claim 1, wherein adjacent electrodes are separated from each other by a separation distance selected from a range that is greater than or equal to 100 μ

m and less than or equal to 1 mm.

6. The device of claim 5, wherein each electrode has an electrode surface area that is less than or equal to 0.2 mm².

7. The device of claim 1, wherein the deformable array of electrodes is supported by a top surface of said barrier layer.

8. The device of claim 7, wherein the electrodes are coated with an electrode coating layer, wherein said electrode coating layer comprises platinum.

9. The device of claim 1 having a thickness, wherein the thickness is less than or equal to 30 μ

m.

10. The device of claim 1, further comprising a support material, said support material having a first surface and a second surface opposed to said first surface, wherein a first portion of said electrodes are supported by said first surface, and a second portion of said electrodes are supported by said second surface.

11. The device of claim 1, further comprising:

a therapeutic device operably connected to the controller; and

a receiving passage through the conformable substrate for receiving at least a portion of the therapeutic device;

wherein the controller is configured to actuate the therapeutic device to provide a therapeutic intervention to the brain.

12. The device of claim 11, wherein the therapeutic device is selected from the group consisting of a penetrating electrode, a micro-syringe and an optical fiber.

13. The device of claim 11, wherein the receiving passage is centered at a center point of the conformable substrate, and the receiving passage has a cross-sectional area selected from a range that is greater than or equal to 100 μ

m² and less than or equal to 1 cm².

14. The device of claim 1, wherein said deformable array of electrodes comprises alternating columns of actuating and monitoring electrodes.

15. The device of claim 1, that provides electrical information at a transfer rate that is greater than or equal to 90,000 samples per second.

16. The device of claim 1, wherein the identified abnormal spatio-temporal brain waveform is a spiral waveform, and wherein the controller is further configured to:

actuate the electrical activity over the brain surface with the output spatio-temporal profile from the deformable array of electrodes to disrupt or terminate the spiral waveform.

17. The device of claim 1, wherein the controller is further configured to:

monitor or actuate the electrical potential of the brain tissue at a plurality of individual brain surface locations over a plurality of different time points;

analyze the monitored electrical potential spatio-temporal profile to identify an electrical waveform;

monitor the magnitude of electric potential at each brain surface location, a time course of electric potential change at each brain surface location, or both; and

calculate the relative delay of a spike in electrical potential at a brain surface location, wherein a spike is identified for any brain surface location having an electric potential that is greater than 50% of a peak root-mean square value over all brain surface locations.

18. A device for spatio-temporally electrically interfacing with a brain in a biological environment, the device comprising:

a conformable substrate;

a conformable electronic circuit comprising a deformable array of electrodes in electrical communication with a plurality of deformable electrical interconnects, the deformable array of electrodes supported by the conformable substrate;

a barrier layer encapsulating at least a portion of the deformable electrical interconnects, wherein the conformable substrate, conformable electronic circuit and the barrier layer provide a net bending stiffness of the device low enough that the device establishes conformal contact with brain tissue in the biological environment; and

a controller connected to the conformable electrical circuit to monitor or actuate a spatio-temporal profile over a surface of the brain in electrical contact with the plurality of electrodes, wherein the controller is configured to;

monitor or actuate the electrical potential of the brain tissue at a plurality of individual brain surface locations over a plurality of different time points;

analyze the monitored electrical potential spatio-temporal profile to identify an electrical waveform;

monitor the magnitude of electric potential at each brain surface location, a time course of electric potential change at each brain surface location, or both; and

calculate the relative delay of a spike in electrical potential at a brain surface location, wherein a spike is identified for any brain surface location having an electric potential that is greater than 50% of a peak root-mean square value over all brain surface locations.