Minimally Invasive Monitoring Methods

• US 20080027347A1
• Filed: 06/21/2007
• Published: 01/31/2008
• Est. Priority Date: 06/23/2006
• Status: Abandoned Application

• Current Assignee: Cyberonics, Inc
• Original Assignee: NeuroVista Corporation
• Inventors: Leyde, Kent, Mavoori, Jaideep, Harris, John
• Application Number:
  US11/766,751
• Publication Number:
  US 20080027347A1
• Time in Patent Office: Days
• US Class Current: 600/544
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/369 Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/372 Analysis of electroencephalograms
• CPC Class Codes: A61B 5/386 Accessories or supplementary instruments therefor
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: A61N 1/36064 Epilepsy
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna

Abstract

The present invention provides methods for minimally invasive, long term monitoring of a physiological signal (e.g., neural signals) from a patient. In preferred embodiments, neural signals are sampled from the patient with an externally powered, leadless implanted device and are transmitted to an external device for further processing.

Claims

1. A method of recording neural signals from a patient, the method comprising:

receiving a wireless signal that interrogates an electronic component of an implanted device that is positioned between the patient'"'"'s scalp and an outer surface of the skull;

sampling the neural signal of the patient with electrodes coupled to the electronic components of the implanted device; and

substantially continuously transmitting a wireless signal that is encoded with data that is indicative of the sampled neural signal from the implanted device to an external device,

wherein the wireless signal that is encoded with data that is indicative of the sampled neural signal is derived from the wireless signal received.

2. The method of claim 1 wherein the implanted device is leadless.

3. The method of claim 2 wherein minimally invasively implanting the leadless device between the patient'"'"'s scalp and skull comprises accessing a space between the patient'"'"'s scalp and skull with an introducer and injecting the leadless device into the space through a lumen of the introducer.

4. The method of claim 3 wherein the implanted leadless device is implanted over a temporal lobe of the patient'"'"'s brain.

5. The method of claim 1 wherein sampling the neural signal of the patient is performed substantially continuously for a time period of at least one day.

6. The method of claim 1 wherein the neural signal comprises an extracranial EEG signal.

7. The method of claim 1 further comprising extracting desired features from the neural signal prior to transmitting, wherein the wireless signal transmitted to the external device is also encoded with the extracted feature.

8. The method of claim 1 wherein the received wireless signal provides power to the electronic components of the implanted device.

9. The method of claim 1 wherein the received wireless signal and transmitted wire signal are radiofrequency signals.

22. The method of claim 1 further comprising powering the electronic components of the implanted device by deriving and storing power from patient-based energy sources.

10. A method of performing brain activity monitoring with a device that is external to a patient, the method comprising:

generating a wireless signal that is configured to provide power to an implanted device and initiate sampling of a neural signal with the implanted device;

receiving a substantially continuous wireless data signal from the implanted device that is encoded with a sampled neural signal;

processing the received data signal in the device that is external to the patient; and

storing the processed data signal in a memory.

11. The method of claim 10 wherein the implanted device is leadless and the generated wireless signal and received wireless data signal are radiofrequency signals.

12. The method of claim 10 wherein processing the received data signal comprises extracting features from the neural signal and classifying the extracted features to estimate the patient'"'"'s brain state that is indicative of the patient'"'"'s propensity for a neurological event.

13. The method of claim 12 further comprising generating an output on a user interface of the device that is external to the patient that is indicative of the patient'"'"'s brain state.

14. The method of claim 11 wherein the wireless data signal from the leadless implanted device is encrypted, wherein processing the received data signal comprises decrypting the data signal.

15. The method of claim 10 wherein the wireless data signal is further encoded with an extracted feature that is indicative of the patient'"'"'s brain state.

16. The method of claim 11 further comprising generating an output communication when the device external to the patient is not receiving the wireless data signal from the leadless implanted device.

17. A method of monitoring and recording EEG signals from a patient, the method comprising:

minimally invasively implanting a leadless device between the patient'"'"'s scalp and skull;

generating a radiofrequency signal in an external device;

receiving the radiofrequency signal with an antenna of the implanted leadless device and using the radiofrequency signal to power up and interrogate components of the implanted device;

sampling an EEG signal with electrodes on the implanted leadless device;

transmitting a return radiofrequency signal substantially continuously from the implanted leadless device, wherein the return radiofrequency signal is encoded with the EEG signal;

receiving the return radiofrequency signal encoded with the EEG signal in the external device;

processing the return radiofrequency signal with the encoded EEG signal in the external device; and

storing the processed return radiofrequency signal in a memory of the external device.

18. The method of claim 17 further comprising encrypting the sampled EEG signal prior to transmitting the return radiofrequency signal.

19. The method of claim 17 further comprising generating an output communication when the external device is not receiving the return radiofrequency signal from the leadless implanted device.

20. The method of claim 17 wherein processing the return radiofrequency signal comprises extracting features from the EEG signal and classifying the extracted features to estimate the patient'"'"'s brain state, wherein the brain state is indicative of the patient'"'"'s propensity for a neurological event.

21. The method of claim 20 further comprising generating an output on a user interface of the external device that is indicative of the patient'"'"'s brain state.

23. A method of recording neural signals from a patient, the method comprising:

powering electronic components of an implanted device by deriving and storing power from patient-based energy sources;

sampling the neural signal of the patient with electrodes coupled to the electronic components of the implanted device; and

substantially continuously transmitting a wireless signal that is encoded with data that is indicative of the sampled neural signal from the implanted device to a portable external device.

24. The method of claim 23 wherein the implanted device is positioned between the patient'"'"'s scalp and an outer surface of the skull.

25. The method of claim 23 further comprising analyzing the data in the portable external device in substantially real-time in order to estimate the patient'"'"'s brain state.