Responsive implantable system for the treatment of neurological disorders

• US 6,134,474 A
• Filed: 01/15/2000
• Issued: 10/17/2000
• Est. Priority Date: 10/27/1997
• Status: Expired due to Term

• Current Assignee: Neuropace Inc.
• Original Assignee: Neuropace Inc.
• Inventors: Fischell, David R., Fischell, Robert E., Upton, Adrian R. M.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US09/483,806
• Time in Patent Office: 276 Days
• Field of Search: 607/45
• US Class Current: 607/45
• CPC Class Codes: A61B 5/369 Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: A61N 1/36025 for treating a mental or cerebral condition
• CPC Class Codes: A61N 1/3605 Implantable neurostimulators for stimulating central or peripheral nerve system
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture

Abstract

Disclosed is a multiple electrode, closed-loop, responsive system for the treatment of certain neurological diseases such as epilepsy, migraine headaches and Parkinson'"'"'s disease. Brain electrodes would be placed in close proximity to the brain or deep within brain tissue. When a neurological event such as the onset of an epileptic seizure occurs, EEG signals from the electrodes are processed by signal conditioning means in a control module that can be placed beneath the patient'"'"'s scalp, within the patient'"'"'s chest, or situated externally on the patient. Neurological event detection means in the control module will then cause a response to be generated for stopping the neurological event. The response could be an electrical signal to brain electrodes or to electrodes located remotely in the patient'"'"'s body. The response could also be the release of medication or the application of a sensory input such as sound, light or mechanical vibration or electrical stimulation of the skin. The response to the neurological event can originate from devices either internal or external to the patient. The system also has the capability for multi-channel recording of EEG related signals that occur both before and after the detection of a neurological event. Programmability of many different operating parameters of the system by means of external equipment provides adaptability for treating patients who manifest different symptoms and who respond differently to the response generated by the system.

Claims

1. A system for detecting and terminating an epileptic seizure of a human patient, the system comprising:

at least one brain electrode adapted to receive seizure detecting electrical signals from the brain of a human patient;

a control module adapted to be implanted within the patient'"'"'s body for transmitting a seizure terminating output signal from the control module for terminating the epileptic seizure responsive to at least one input seizure detecting electrical signal originating from the at least brain electrode in the patient'"'"'s brain, the control module comprising electronic circuitry, the electronic circuitry of the control module comprising an event detection sub-system that is adapted to identify electrical activity associated with the occurrence of an epileptic seizure by processing the at least one input seizure detecting electrical signal from the at least one electrode, the event detection sub-system comprising amplification means, analog-to-digital conversion means and epileptic seizure detection means, the amplification means being adapted for increasing the amplitude of the seizure detecting electrical signals received by the control module from the at least one brain electrode to produce one or more amplified signals, the analog-to-digital conversion means being adapted for converting the one or more amplified signals to one or more digital EEG signals and the seizure detection means being adapted for comparing at least one characteristic of the one or more digital EEG signals against a preset threshold level for that characteristic;

electrical conducting means for providing electrical connections between the at least one electrode and the control module; and

external equipment means adapted to be located external to the human patient for providing two-way communication between the external equipment means and control module for (1) receiving data transmission from the control module and (2) transmitting signals to be received by the control module for (a) setting the preset threshold level, and (b) defining the seizure terminating output signal from the control module, whereby the seizure terminating output signal provides a stimulation signal to terminate the epileptic seizure detected by the control module'"'"'s event detection sub-system.

2. A system for detecting and terminating an epileptic seizure of a human patient, the system comprising:

at least one brain electrode adapted to receive seizure detecting electrical signals from the brain of a human patient;

a control module adapted to be implanted within the patient'"'"'s body for transmitting a seizure terminating output signal from the control module for terminating the epileptic seizure responsive to at least one input seizure detecting electrical signal originating from the at least brain electrode in the patient'"'"'s brain, the control module comprising electronic circuitry, the electronic circuitry of the control module comprising an event detection sub-system that is adapted to identify electrical activity associated with the occurrence of an epileptic seizure by processing the at least one input seizure detecting electrical signal from the at least one electrode, the event detection sub-system comprising amplification means, analog-to-digital conversion means and epileptic seizure detection means, the amplification means being adapted for increasing the amplitude of the seizure detecting electrical signals received by the control module from the at least one brain electrode to produce one or more amplified signals, the analog-to-digital conversion means being adapted for converting the one or more amplified signals to one or more digital EEG signals and the seizure detection means being adapted for detecting the onset of an epileptic seizure, the seizure detection means comprising a first step which is the detection of an individual event within the one or more digital EEG signals when at least one characteristic of the one or more digital EEG signals exceeds a preset threshold level of that characteristic and a second step which is the declaring of a positive detection of a seizure when the counted number of individual events detected in a preset time interval exceeds a preset number of counts;

electrical conducting means for providing electrical connections between the at least one electrode and the control module; and

external equipment means adapted to be located external to the human patient for providing two-way communication between the external equipment means and control module for (1) receiving data transmission from the control module and (2) transmitting signals to be received by the control module for (a) setting the preset threshold level, (b) setting the preset time interval, (c) setting the preset number of counts, and (d) defining the seizure terminating output signal from the control module, whereby the seizure terminating output signal provides a stimulation signal to terminate the epileptic seizure detected by the control module'"'"'s event detection sub-system.

3. A system for detecting an epileptic seizure of a human patient, the system comprising:

at least one brain electrode adapted to receive seizure detecting electrical signals from the brain of a human patient;

a control module adapted to be implanted within the patient'"'"'s body for detecting the epileptic seizure, the control module comprising electronic circuitry, the electronic circuitry of the control module comprising an event detection sub-system that is adapted identify electrical activity associated with the occurrence of an epileptic seizure by processing the at least one input seizure detecting electrical signal from the at least one electrode, the event detection sub-system comprising amplification means, analog-to-digital conversion means and epileptic seizure detection means, the amplification means being adapted for increasing the amplitude of the electrical signals received by the control module from the at least one brain electrode to produce one or more amplified signals, the analog-to-digital conversion means being adapted for converting the one or more amplified signals to one or more digital EEG signals and the seizure detection means being adapted for detecting the onset of an epileptic seizure, the seizure detection means comprising a first step which is the detection of an individual event that occurs within the one or more digital EEG signals when at least one characteristic of the one or more digital EEG signals exceeds a preset threshold level of that characteristic and a second step which is the declaring of a positive detection of a seizure when the counted number of the individual events detected in a preset time interval exceeds a preset number of counts;

electrical conducting means for providing electrical connections between the at least one electrode and the control module; and

external equipment means adapted to be located external to the human patient for providing two-way communication between the external equipment means and control module for (1) receiving data transmission from the control module and (2) transmitting signals to be received by the control module for (a) setting the preset threshold level, (b) setting the preset time interval, and (c) setting the preset number of counted individual events used by the event detection sub-system seizure detection means to identify the occurrence of an epileptic seizure.

4. A system for detecting a first neurological event which is a precursor of a second neurological event which second neurological event is the clinical manifestations of a neurological disorder that is predicted by the occurrence of the first neurological event, at least part of the system being adapted to prevent the clinical manifestation of the neurological disorder and further adapted to be implanted within a human subject, the system comprising:

at least one brain electrode adapted to receive an electrical signal from one spatial region within the brain of the human patient, the electrical signal being indicative of the occurrence of the first neurological event;

a control module adapted to be implanted within the patient'"'"'s body for detecting the electrical signal from the at least one electrode and further being adapted to provide a responsive electrical signal prior to the occurrence of the second neurological event, the responsive electrical signal causing at least one pre-determined stimulus to be applied to the brain tissue of the human patient, the at least one predetermined stimulus being adapted to act upon the brain tissue of the human patient to prevent the occurrence of the second neurological event; and

,

electrical conducting means for providing electrical connections between the at least one electrode and the control module.

5. The system of claim 4 wherein the at least one stimulus applied to the patient'"'"'s brain is a neurological event preventing electrical stimulus initiated by the responsive electrical signal, the electrical stimulus being adapted to prevent the occurrence of the second neurological event.

6. The system of claim 4 wherein the at least one stimulus applied to the patient'"'"'s brain is the release of a medication which release is initiated by the responsive electrical signal, the medication being adapted to prevent the occurrence of the second neurological event.

7. The system of claim 6 wherein the medication is released into the cerebrospinal fluid of the human patient.

8. The system of claim 4 wherein two stimuli are applied to the brain, the first stimulus being a neurological event stopping electrical stimulus and the second stimulus being the release of medication, both of the stimuli being initiated by the responsive electrical signal, both of the stimuli being adapted to function co-operatively to prevent the occurrence of the second neurological event.

9. The system of claim 8 wherein the medication is released into the cerebrospinal fluid of the human patient.

10. The system of claim 4 wherein the first neurological event is an EEG signal that is a precursor of an epileptic seizure and the second neurological event is the clinical manifestations of the epileptic seizure.

11. The system of claim 10 wherein the spatial region of the brain where the at least one electrode is adapted to be implanted is an epileptic focus.

12. The system of claim 4 wherein the spatial region of the brain into which the at least one electrode is adapted to be implanted is the hippocampus.

13. The system of claim 4 wherein the first neurological event is a precursor of a migraine headache and the second neurological event is the clinical manifestations of that migraine headache, the clinical manifestations of the migraine headache being a pain in the head of the human patient.

14. The system of claim 4 wherein the first neurological event is a precursor of the tremor associated with Parkinson'"'"'s syndrome and the second neurological event is the clinical manifestations of that Parkinson'"'"'s syndrome, the clinical manifestations being the involuntary motion of some part of the body of the human patient.

15. The system of claim 14 wherein the spatial region of the brain into which the at least one electrode is adapted to be placed is the thalamus.

16. The system of claim 14 wherein the at least one stimulus applied to the brain of the human patient is a neurological event preventing electrical stimulus that is initiated by the responsive electrical signal.

17. The system of claim 14 wherein the at least one stimulus applied to the brain of the human patient is the release of medication, the release being initiated by the responsive electrical signal.

18. The system of claim 17 wherein the medication is released into the cerebrospinal fluid of the human patient.

19. The system of claim 18 wherein the medication released into the cerebrospinal fluid is epinephrine.

20. The system of claim 14 wherein two stimuli are applied to the brain, the first stimulus being a tremor preventing electrical stimulus and the second stimulus being the release of medication, both of the stimuli being initiated by the responsive electrical signal, both of the stimuli being adapted to function co-operatively to prevent the occurrence of the second neurological event.

21. A system for detecting a precursor of an epileptic seizure and for applying a seizure preventing signal to prevent the clinical manifestations of an epileptic seizure of a human patient, the system comprising:

at least one brain electrode adapted to receive seizure precursor electrical signals from the brain of a human patient;

a control module adapted to be implanted within the patient'"'"'s body for transmitting a seizure preventing output signal from the control module for preventing the clinical manifestations of the epileptic seizure responsive to at least one input seizure precursor electrical signal originating from the at least brain electrode in the patient'"'"'s brain, the control module comprising electronic circuitry, the electronic circuitry of the control module comprising an event detection sub-system that is adapted to identify electrical activity associated with the occurrence of a precursor of an epileptic seizure by processing the at least one input seizure precursor electrical signal from the at least one electrode, the event detection sub-system comprising amplification means, analog-to-digital conversion means and epileptic seizure precursor detection means, the amplification means being adapted for increasing the amplitude of the seizure precursor electrical signals received by the control module from the at least one brain electrode to produce one or more amplified signals, the analog-to-digital conversion means being adapted for converting the one or more amplified signals to one or more digital EEG signals and the seizure precursor detection means being adapted for comparing at least one characteristic of the one or more digital EEG signals against a preset threshold level for that characteristic;

electrical conducting means for providing electrical connections between the at least one electrode and the control module; and

external equipment means adapted to be located external to the human patient for providing two-way communication between the external equipment means and control module for (1) receiving data transmission from the control module and (2) transmitting signals to be received by the control module for (a) setting the preset threshold level, and (b) defining the seizure preventing output signal from the control module, whereby the seizure preventing output signal provides a seizure preventing stimulus to prevent the clinical manifestations of the epileptic seizure.

22. A system for detecting a precursor of an epileptic seizure and for applying a seizure preventing signal to prevent the clinical manifestations of an epileptic seizure of a human patient, the system comprising:

at least one brain electrode adapted to receive seizure precursor electrical signals from the brain of a human patient;

a control module adapted to be implanted within the patient'"'"'s body for transmitting a seizure preventing output signal from the control module for preventing the epileptic seizure responsive to at least one input seizure precursor electrical signal originating from the at least brain electrode in the patient'"'"'s brain, the control module comprising electronic circuitry, the electronic circuitry of the control module comprising an event detection sub-system that is adapted to identify electrical activity associated with the occurrence of a precursor of an epileptic seizure by processing the at least one input seizure precursor electrical signal from the at least one electrode, the event detection sub-system comprising amplification means, analog-to-digital conversion means and epileptic seizure detection means, the amplification means being adapted for increasing the amplitude of the seizure precursor electrical signals received by the control module from the at least one brain electrode to produce one or more amplified signals, the analog-to-digital conversion means being adapted for converting the one or more amplified signals to one or more digital EEG signals and the seizure precursor detection means being adapted for detecting the precursor of the onset of the epileptic seizure, the seizure precursor detection means comprising a first step which is the detection of an individual event within the one or more digital EEG signals by comparing at least one characteristic of the one or more digital EEG signals against a preset threshold level for that characteristic and a second step which is the declaring of a positive detection of a precursor of the seizure when the counted number of individual events detected in a preset time interval exceeds a preset number of counts, the declaring of a positive detection of a precursor of the seizure causing a responsive output signal to be produced by the control module which responsive signal is the seizure preventing output signal

electrical conducting means for providing electrical connections between the at least one electrode and the control module; and

external equipment means adapted to be located external to the human patient for providing two-way communication between the external equipment means and control module for (1) receiving data transmission from the control module and (2) transmitting signals to be received by the control module for (a) setting the preset threshold level, (b) setting the preset time interval, (c) setting the preset number of counts, and (d) defining the seizure preventing output signal from the control module, whereby the seizure preventing output signal provides a seizure preventing stimulus to prevent the epileptic seizure from occurring.