MULTI-CHANNEL BRAIN OR CORTICAL ACTIVITY MONITORING AND METHOD

• US 20110130675A1
• Filed: 12/01/2009
• Published: 06/02/2011
• Est. Priority Date: 12/01/2009
• Status: Active Grant

• Current Assignee: NeuroWave Systems Inc.
• Original Assignee: NeuroWave Systems Inc.
• Inventors: Zikov, Tatjana, Bibian, Stéphane
• Granted Patent: US 8,838,226 B2
• Time in Patent Office: Days
• US Class Current: 600/544
• CPC Class Codes: A61B 5/369 Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/4064 Evaluating the brain A61B5/031, A61B5/369, A61B5/14553 take precedence
• CPC Class Codes: A61B 5/4082 Diagnosing or monitoring movement diseases, e.g. Parkinson, Huntington or Tourette
• CPC Class Codes: A61B 5/4821 Determining level or depth of anaesthesia A61B5/1106 takes precedence
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

The present invention relates to a quantitative electroencephalogram (QEEG) monitor and system capable of monitoring and displaying simultaneously neuropathological characteristic and activity of both sides of a subject'"'"'s brain. The methods include various indices and examination of differences in these indices by which neurophysiological conditions or problems can be identified and treated. These methods, and the systems and devices using these methods preferably can be used for identifying these neurophysiological conditions or brain dysfunction with monitors and methods for seizure detection, for sedation monitoring, for anesthesia monitoring, and the like. These bilateral brain monitoring methods and systems, and the devices using these methods can be used by individuals or clinicians with little or no training in signal analysis or processing. These bilateral monitoring methods can also be used in a range of applications.

Claims

1. A method of determining EEG signal quality in a device for quantifying brain or cortical activity during sedation or anesthesia comprising steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain;

d. displaying at least two indices corresponding to the brain or cortical activity of the left and right hemispheres on a monitor simultaneously;

e. comparing the indices of each hemisphere'"'"'s cortical activity; and

f. determining whether the signal of at least one of the EEG electrodes is likely to have poor quality.

2. The method of claim 1 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining whether the subject has suffered, or is suffering some neuropathological activity.

3. The method of claim 1 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining if the subject'"'"'s status has suddenly changed indicating wakefulness or awareness in at least one hemisphere of the subject'"'"'s brain.

4. The method of claim 1 wherein the system provides a message, either audible or visual, or a combination thereof, notifying a caregiver when signal quality is low in a given electrode, some neuropathological activity is detected, or the subject'"'"'s status changes suddenly.

5. The method of claim 1 where the indices are displayed on a monitor in color, that color corresponding to the color of the electrode lead connector, or electrode label, or the electrode lead wire used to attach the processor to the given side of the subject'"'"'s head.

6. A method of detecting neuropathological activity with a device for quantifying brain or cortical activity in a subject during sedation or anesthesia comprising the steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain;

d. displaying the at least two indices corresponding to the brain or cortical activity of the left and right hemispheres on a monitor simultaneously;

e. comparing the indices of each hemisphere'"'"'s cortical activity; and

f. determining whether the brain or cortical activity of one hemisphere of the brain is indicative of a neuropathological condition when compared to the brain or cortical activity of the other hemisphere of the brain of the subject.

7. The method of claim 6 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining whether the signal of one or more of the EEG electrodes is likely to have poor signal quality.

8. The method of claim 6 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining if the subject'"'"'s status has changed suddenly indicating wakefulness or awareness.

9. The method of claim 6 wherein the system provides a message, either audible or visual, or a combination thereof, notifying a caregiver when signal quality is low in a given electrode, some neuropathological activity is detected, or the subject'"'"'s status changes suddenly.

10. The method of claim 6 where the indices are displayed on a monitor in color, that color corresponding to the color of the electrode lead connector, or electrode label, or the electrode lead wire used to attach the processor to the given side of the subject'"'"'s head.

11. A method of detecting a sudden change in subject status with a device for quantifying brain or cortical activity in the subject during sedation or anesthesia comprising the steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain;

d. displaying the at least two indices corresponding to the brain or cortical activity of the left and right hemispheres on a monitor simultaneously;

e. comparing the indices of each hemisphere'"'"'s cortical activity; and

f. determining whether the brain or cortical activity of one hemisphere of the brain is indicative of a change in subject status when compared to the brain or cortical activity of the other hemisphere of the brain of the subject.

12. The method of claim 11 wherein the change in subject status corresponds to a reaction of the patient following noxious stimulation.

13. The method of claim 11 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining whether the signal of one or more of the EEG electrodes is likely to have poor signal quality.

14. The method of claim 11 wherein an additional step is comparing the calculated brain or cortical activity indices for each of the subject'"'"'s brain hemispheres and determining whether the subject has suffered, or is suffering some neuropathological activity.

15. The method of claim 11 wherein the system provides a message, either audible or visual, or a combination thereof, notifying a caregiver when signal quality is low in a given electrode, some neuropathological activity is detected, or the subject'"'"'s status changes suddenly.

16. The method of claim 11 where the indices are displayed on a monitor in color, that color corresponding to the color of the electrode lead connector, or electrode label, or the electrode lead wire used to attach the processor to the given side of the subject'"'"'s head.

17. A method of closed-loop or semi-automatic anesthesia or sedative drug delivery to a subject with a device for quantifying brain or cortical activity comprising the steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain;

d. comparing the indices of each hemisphere'"'"'s cortical activity; and

e. determining the subject'"'"'s need for additional anesthesia or sedation based on a least risk approach calculated by comparing the indices of each hemisphere'"'"'s cortical activity.

18. The method of claim 17 where at least two indices corresponding to the brain or cortical activity of the left and right hemispheres are displayed on a monitor simultaneously.

19. The method of claim 17 wherein the system provides a message, either audible or visual, or a combination thereof, notifying a caregiver when signal quality is low in a given electrode, some neuropathological activity is detected, or the subject'"'"'s status changes suddenly.

20. The method of claim 17 where the indices are displayed on a monitor in color, that color corresponding to the color of the electrode lead connector, or electrode label, or the electrode lead wire used to attach the processor to the given side of the subject'"'"'s head.

21. A method of providing a message to the user of a device for quantifying brain or cortical activity during sedation or anesthesia comprising steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain;

d. comparing the indices of each hemisphere'"'"'s cortical activity; and

e. displaying a message, either audible or visual, or a combination thereof, notifying a caregiver that some attention is needed by the patient or by the brain or cortical activity quantification device.

22. A method for comparative electroencephalography in monitoring brain function in a plurality of distinct brain regions of the same subject on a continuous and substantially concurrent basis, comprising the steps of:

a. applying at least one electroencephalographic measurement electrode at each of said plurality of brain regions, and applying at least one reference electrode, and coupling each measurement and reference electrode to a control and processing system;

b. continuously acquiring an electroencephalographic signal from each of said electroencephalographic measurement electrodes;

c. separately and concurrently calculating for each said electroencephalographic signal at least one quantitative electroencephalographic index representative of the brain activity of the brain region corresponding to the measurement electrode;

d. concurrently visually displaying at least one quantitative electroencephalographic index for each of at least two distinct brain regions; and

e. administrating a drug or therapeutics to said subject based on a comparison of at least two quantitative electroencephalographic measures.

23. The method of claim 22 where the EEG signals obtained from said distinct brain regions are displayed concurrently with the corresponding quantitative electroencephalographic index.

24. The method of claim 23 where at least three quantitative electroencephalographic indices corresponding to distinct brain regions are displayed in a spider graph.

25. A method of detecting a sudden change in subject status with a device for quantifying brain or cortical activity in the subject during sedation or anesthesia comprising the steps of:

a. monitoring a subject with a brain having a left hemisphere and a right hemisphere, by hooking the subject up to a brain or cortical activity quantification device with at least two measurement electrodes, and at least one reference electrode, the at least two measurement electrodes comprising at least one EEG electrode, having a signal, positioned to monitor left hemisphere brain or cortical activity and at least one EEG electrode, having a signal, positioned to monitor right hemisphere brain or cortical activity of the subject'"'"'s brain, the reference electrode comprising at least one EEG electrode, each electrode providing an EEG signal to a processor;

b. measuring the brain or cortical activity of both the subject'"'"'s left and right brain hemispheres essentially simultaneously;

c. calculating with the processor at least one QEEG index using a wavelet transform and corresponding to the brain or cortical activity of each of the left and right hemispheres of the subject'"'"'s brain; and

d. displaying at least one index corresponding to the brain or cortical activity of either the left and right hemispheres on a monitor.