Sleep stage detection

• US 9,706,957 B2
• Filed: 06/08/2015
• Issued: 07/18/2017
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Wu, Jianping, Molnar, Gregory F., Molnar, Gabriela C., Denison, Timothy J.
• Primary Examiner(s): Porter, Jr., Allen
• Application Number:
  US14/733,349
• Publication Number:
  US 20150265207A1
• Time in Patent Office: 771 Days
• Field of Search: 607 45
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/291 for electroencephalography [EEG]
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/374 Detecting the frequency distribution of signals, e.g. detecting delta, theta, alpha, beta or gamma waves
• CPC Class Codes: A61B 5/4082 Diagnosing or monitoring movement diseases, e.g. Parkinson, Huntington or Tourette
• CPC Class Codes: A61B 5/4812 Detecting sleep stages or cycles
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61M 2005/1726 the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 2021/0072 with application of electrical currents
• CPC Class Codes: A61M 21/02 for inducing sleep or relaxation, e.g. by direct nerve stimulation, hypnosis, analgesia for massage A61H; electrotherapy A61N, e.g. applying alternating or intermittent electric currents for producing anaesthesia A61N1/36021
• CPC Class Codes: A61M 2205/3523 using telemetric means
• CPC Class Codes: A61M 2205/3553 remote, e.g. between patient's home and doctor's office
• CPC Class Codes: A61M 2205/3584 using modem, internet or bluetooth
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/50 : with microprocessors or computers
• CPC Class Codes: A61M 2205/52 : with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2230/005 : Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/04 : Heartbeat characteristics, e.g. ECG, blood pressure modulation
• CPC Class Codes: A61M 2230/08 : Other bio-electrical signals
• CPC Class Codes: A61M 2230/10 : Electroencephalographic signals
• CPC Class Codes: A61M 2230/205 : partial oxygen pressure (P-O2)
• CPC Class Codes: A61M 2230/30 : Blood pressure A61M2230/04 takes precedence
• CPC Class Codes: A61M 2230/42 : Rate
• CPC Class Codes: A61M 2230/50 : Temperature
• CPC Class Codes: A61M 2230/60 : Muscle strain, i.e. measured on the user
• CPC Class Codes: A61M 2230/63 : Motion, e.g. physical activity
• CPC Class Codes: A61M 2230/65 : Impedance, e.g. conductivity, capacity
• CPC Class Codes: A61M 5/1723 : using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: A61N 1/36078 : Inducing or controlling sleep or relaxation non-implantable stimulator A61M21/00
• CPC Class Codes: A61N 1/36139 : with automatic adjustment
• CPC Class Codes: G16H 20/17 : delivered via infusion or injection
• CPC Class Codes: G16H 20/30 : relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising
• CPC Class Codes: G16H 20/70 : relating to mental therapies, e.g. psychological therapy or autogenous training
• CPC Class Codes: G16H 40/63 : for local operation

Abstract

Therapy delivery to a patient may be controlled based on a determined sleep stage of the patient. In examples, the sleep stage may be determined based on a frequency characteristic of a biosignal indicative of brain activity of the patient. A frequency characteristic may include, for example, a power level within one or more frequency bands of the biosignal, a ratio of the power level in two or more frequency bands, or a pattern in the power level of one or more frequency bands over time. A therapy program may be selected or modified based on the sleep stage determination. Therapy may be delivered during the sleep stage according to the selected or modified therapy program. In some examples, therapy delivery may be controlled after making separate determinations of a sleep stage based on the biosignal and another physiological parameter, and confirming that the sleep stage determinations are consistent.

Claims

1. A system comprising:

a medical device configured to be implanted in a patient, the medical device comprising a therapy module configured to deliver therapy to a patient;

a sensing module;

external electrodes configured to be located external to the patient and electrically coupled to the sensing module, wherein the sensing module is configured to sense a brain signal of the patient via the external electrodes; and

a processor configured to receive the brain signal from the sensing module, detect a non-REM sleep stage of the patient based on the brain signal, and, in response to detecting the non-REM sleep stage, control the therapy module to deliver therapy configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy.

2. The system of claim 1, wherein the non-REM sleep stage comprises one or more of a Stage 1 sleep stage, a Stage 2 sleep stage, or a Deep Sleep sleep stage.

3. The system of claim 1, wherein the processor is configured to detect the non-REM sleep stage by at least:

determining a frequency characteristic of the brain signal, and

determining a sleep stage of the patient based on the determined frequency characteristic of the brain signal.

4. The system of claim 3, wherein the frequency characteristic comprises at least one of:

a power level of the brain signal within one or more frequency bands, a ratio of power levels in two or more frequency bands of the brain signal, or a trend in a power level of the brain signal within one or more frequency bands over time.

5. The system of claim 3, wherein the sensing module comprises a first sensing module, the system further comprising a second sensing module configured to generate a physiological signal indicative of a physiological parameter of the patient, wherein the physiological signal is different than the brain signal, wherein the processor is configured to determine a first sleep stage based on the frequency characteristic of the brain signal, receive the physiological signal from the second sensing module, determine a second sleep stage based on the physiological signal, and determine the sleep stage of the patient based on the first and second sleep stage determinations.

6. The system of claim 1, wherein the sensing module is separate from the medical device.

7. The system of claim 1, wherein the therapy comprises electrical stimulation therapy.

8. The system of claim 7, wherein the electrical stimulation therapy comprises deep brain electrical stimulation therapy.

9. The system of claim 1, wherein the therapy comprises delivery of a therapeutic agent.

10. The system of claim 1, wherein the processor is configured to determine the patient is in at least one of an awake state, a first sleep stage or a second sleep stage based on a frequency characteristic of the brain signal, and control the therapy module to activate therapy delivery to the patient in response to determining the patient is in the awake state or the first sleep stage and control the therapy module to deactivate or decrease an intensity of therapy delivered to the patient in response to determining the patient is in the second sleep stage.

11. The system of claim 10, wherein the first sleep stage comprises at least one of a Stage 1 or rapid eye movement sleep stage and the second sleep stage comprises at least one of a Deep Sleep or Stage 2 sleep stage.

12. The system of claim 1, wherein the processor is further configured to detect a REM sleep stage of the patient based on the brain signal and control the therapy module to, in response to detecting the REM sleep stage, to deliver therapy that minimizes movement of the patient relative to the patient state in which the patient is not receiving the therapy.

13. The system of claim 1, wherein the processor is configured to determine whether the patient is in a sleep state.

14. The system of claim 13, wherein the sensing module comprises a first sensing module, the system further comprising a second sensing module configured to generate a physiological signal indicative of a physiological parameter of the patient, wherein the physiological parameter comprises at least one of an activity level, posture, heart rate, electrocardiogram morphology, or core temperature, wherein the processor is configured to receive the physiological signal and determine whether the patient is in the sleep state based on the physiological signal.

15. The system of claim 1, wherein the brain signal comprises an electrocorticogram (ECoG) signal.

16. The system of claim 1, wherein the brain signal comprises an electroencephalogram (EEG) signal.

17. The system of claim 1, wherein the processor is configured to control the therapy module to deliver therapy configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy by at least controlling the therapy module to deliver therapy configured to improve performance of one or more of initiating movement or maintaining movement by the patient relative to a patient state in which the patient is not receiving the therapy.

18. A method comprising:

receiving, by a processor, a brain signal of a patient sensed by a sensing module via external electrodes electrically coupled to the sensing module, wherein the external electrodes are located external to the patient;

detecting, by the processor, a non-REM sleep stage of the patient based on the brain signal; and

in response to detecting the non-REM sleep stage, controlling, by the processor, a therapy module of an implantable medical device to deliver therapy configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy.

19. The method of claim 18, wherein receiving the brain signal comprises receiving the brain signal sensed by the sensing module via the external electrodes placed on a scalp of the patient.

20. The method of claim 18, wherein the brain signal comprises an electrocorticogram (ECoG) signal.

21. The method of claim 18, wherein the brain signal comprises an electroencephalogram (EEG) signal.

22. The method of claim 18, wherein the non-REM sleep stage comprises one or more of a Stage 1 sleep stage, a Stage 2 sleep stage, or a Deep Sleep sleep stage.

23. The method of claim 18, wherein detecting the non-REM sleep stage comprises:

determining a frequency characteristic of the brain signal, and

determining a sleep stage of the patient based on the determined frequency characteristic of the brain signal.

24. The method of claim 18, further comprising:

determining a first sleep stage determination based on the brain signal;

receiving a physiological signal indicative of a physiological parameter of the patient, wherein the physiological signal is different than the brain signal; and

determining a second sleep stage determination based on the physiological signal, wherein detecting the non-REM sleep stage of the patient comprises detecting the non-REM sleep stage based on the first and second sleep stage determinations.

25. The method of claim 18, wherein receiving the brain signal comprises receiving the brain signal from the sensing module that is separate from the implantable medical device.

26. The method of claim 18, wherein the therapy comprises electrical stimulation therapy.

27. The method of claim 18, wherein the therapy comprises delivery of a therapeutic agent.

28. The method of claim 18, further comprising:

determining, by the processor, the patient is in at least one of an awake state, a first sleep stage or a second sleep stage based on a frequency characteristic of the brain signal; and

controlling, by the processor, the therapy module to activate therapy delivery to the patient in response to determining the patient is in the awake state or the first sleep stage, and deactivate or decrease an intensity of therapy delivered to the patient in response to determining the patient is in the second sleep stage.

29. The method of claim 28, wherein the first sleep stage comprises at least one of a Stage 1 or rapid eye movement sleep stage and the second sleep stage comprises at least one of a Deep Sleep or Stage 2 sleep stage.

30. The method of claim 18, further comprising:

detecting, by the processor, a REM sleep stage of the patient based on the brain signal and

controlling, by the processor, the therapy module to deliver therapy that minimizes movement of the patient relative to the patient state in which the patient is not receiving the therapy in response to detecting the REM sleep stage.

31. The method of claim 18, further comprising:

determining, by the processor, a physiological parameter of the patient, wherein the physiological parameter comprises at least one of an activity level, posture, heart rate, electrocardiogram morphology or core temperature; and

determining whether the patient is in a sleep state based on the physiological parameter of the patient.

32. The method of claim 18, wherein controlling, by the processor, the therapy module to deliver therapy configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy comprises controlling, by the processor, the therapy module to deliver therapy configured to improve performance of one or more of initiating movement or maintaining movement by the patient relative to a patient state in which the patient is not receiving the therapy.

33. A system comprising:

an implantable medical device comprising a therapy module;

means for detecting a non-REM sleep stage of a patient based on a brain signal sensed via external electrodes located external to the patient; and

means for controlling the therapy module of the implantable medical device to deliver therapy to the patient configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy in response to detection of the non-REM sleep stage by the means for detecting.

34. The system of claim 33, further comprising means for detecting a REM sleep stage of the patient based on the brain signal, wherein the means for controlling controls the means for delivering therapy to deliver therapy that minimizes movement of the patient relative to the patient state in which the patient is not receiving the therapy in response to detection of the REM sleep stage by the means for detecting.

35. A non-transitory computer-readable medium comprising instructions that cause a processor to:

receive a brain signal of a patient sensed by a sensing module via external electrodes electrically coupled to the sensing module, wherein the external electrodes are located external to the patient;

detect a non-REM sleep stage of the patient based on the brain signal; and

in response to detecting the non-REM sleep stage, control a therapy module of an implantable medical device to deliver therapy configured to improve performance of one or more motor tasks by the patient relative to a patient state in which the patient is not receiving the therapy.

36. The non-transitory computer-readable medium of claim 35, further comprising instructions that cause the processor to detect a REM sleep stage of the patient based on the brain signal, and, in response to detecting the REM sleep stage, control the therapy module to deliver therapy that minimizes movement of the patient relative to the patient state in which the patient is not receiving the therapy.