Wireless intracranial monitoring system

• US 9,901,269 B2
• Filed: 10/16/2015
• Issued: 02/27/2018
• Est. Priority Date: 04/17/2014
• Status: Active Grant

• Current Assignee: Branchpoint & AURA Development LLC
• Original Assignee: Branchpoint Technologies, Inc.
• Inventors: Hu, Nicholas, Hughes, Kevin, Phouasalit, Hyung
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US14/885,884
• Publication Number:
  US 20160066803A1
• Time in Patent Office: 865 Days
• Field of Search: 600561
• CPC Class Codes: A61B 2090/103 Cranial plugs for access to brain
• CPC Class Codes: A61B 2560/0257 using atmospheric pressure
• 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 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/036 by means introduced into body tracts A61B5/032 and A61B5/035 take precedence
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61B 90/11 with guides for needles or instruments, e.g. arcuate slides or ball joints

Abstract

Systems and methods for monitoring physiological parameters such as intracranial pressure (“ICP”), intracranial temperature, and subject head position are provided. In some embodiments, an implantable apparatus for measuring ICP can be implanted into a subject skull. The apparatus can comprise an implant body having a hermetically sealed chamber housing a gas at a reference pressure, and a pressure conduction catheter having a proximal end and a distal end, wherein the distal end is configured to extend into the brain through a burr hole in the skull and includes a plurality of ports. A barrier can cover the ports of the distal end of the pressure conduction catheter, wherein the barrier and pressure conduction catheter are filled with a number of gas molecules so that the barrier is not in tension in a predefined range of ICPs. The ports may also be configured such that a barrier is not necessary. Standoffs on the body may be included that stabilize the implant on the skull and enhance reliability and robustness of the measurements.

Claims

1. An implantable apparatus for measuring intracranial pressure (ICP) in a brain housed within a skull, comprising:

a body having a proximal side and a distal side with at least one standoff coupled with and extending distally away from the distal side of the body and spaced radially outward from a central axis of the body, the at least one standoff configured to contact an outer portion of the skull;

a pressure conduction catheter having a proximal end and a distal end, the proximal end coupled with the body, wherein the distal end is configured to extend into the brain through a burr hole in the skull and includes a plurality of ports;

a diaphragm in pressure communication with the pressure conduction catheter, the diaphragm configured to deform in response to changes in ICP at the plurality of ports;

at least one sensor configured to obtain data indicative of deformation of the diaphragm; and

a processor, configured to receive said obtained data and determine the ICP at the plurality of ports based at least in part on the obtained data.

2. The apparatus of claim 1, wherein the processor is positioned within a hermetically-sealed implant body.

3. The apparatus of claim 2, wherein the diaphragm and hermetically-sealed implant body are unibody.

4. The apparatus of claim 2, wherein the hermetically-sealed implant body includes a reference pressure.

5. The apparatus of claim 2, further comprising a data antenna operably coupled to the processor.

6. The apparatus of claim 5, wherein the data antenna is coupled to the processor through a hermetic feedthrough.

15. The apparatus of claim 1, further comprising a barrier configured to cover the ports of the distal end of the pressure conduction catheter, wherein the barrier and pressure conduction catheter are filled with a predetermined number of gas molecules so that the barrier is not in tension in at least a predefined range of ICPs.

16. The apparatus of claim 15, wherein the barrier is not in tension in at least a predefined range of atmospheric pressures.

17. The apparatus of claim 15, wherein the barrier does not collapse onto the pressure conduction catheter in at least the predefined range of ICPs.

19. The apparatus of claim 16, wherein the barrier does not collapse onto the pressure conduction catheter in at least the predefined range of ICPs.

20. The apparatus of claim 16, wherein the barrier is not in tension in at least a predefined range of atmospheric pressures.

21. The apparatus of claim 15, wherein the predefined range of ICPs is −

100 mmHg to 150 mmHg.

23. The apparatus of claim 1, wherein the body comprises the diaphragm.

24. The apparatus of claim 23, wherein the diaphragm and body are unibody.

30. The apparatus of claim 1, wherein the at least one standoff comprises a plurality of standoffs.

31. The apparatus of claim 30, wherein the plurality of standoffs are evenly spaced angularly about the central axis.

32. The apparatus of claim 31, wherein the plurality of standoffs are positioned radially a same distance from the central axis.

33. The apparatus of claim 1, wherein the at least one standoff comprises a projection extending circumferentially about the central axis.

7. A method for measuring intracranial pressure (ICP) in a brain housed within a skull, comprising:

extending a distal end of a pressure conduction catheter of an implant into a brain through a burr hole in a skull;

contacting an outer portion of the skull with at least one standoff of the implant, the at least one standoff coupled with and extending distally away from a distal side of the implant and spaced radially outward from a central axis of the implant;

deforming a diaphragm of the implant that is in pressure communication with the pressure conduction catheter, the diaphragm configured to deform based at least in part on changes in ICP at a plurality of ports at the distal end of the pressure conduction catheter;

obtaining data indicative of the deformation of the diaphragm; and

determining ICP at the plurality of ports based at least in part on at least said obtained data.

8. The method of claim 7, further comprising transmitting the determined ICP through a hermetic feedthrough to a data antenna.

9. The method of claim 8, further comprising transmitting the determined ICP from the data antenna to a transceiver external to the skull.

10. The method of claim 7, wherein the data indicative of deformation is at least one of stress, strain, and deflection.

11. The method of claim 7, wherein the diaphragm comprises titanium.

12. The method of claim 7, wherein the ICP is determined for a predetermined range of ICPs, and wherein the predefined range of ICPs is −

100 mmHg to 150 mmHg.

13. An implantable apparatus for measuring intracranial pressure (ICP) in a brain housed within a skull, comprising:

an implant body comprising a hermetically sealed chamber housing a gas at a reference pressure, the body having at least one standoff coupled with and extending distally from the body and spaced radially outward from a central axis of the body;

a pressure conduction catheter having a proximal end and a distal end, wherein the distal end is configured to extend into the brain through a burr hole in the skull and includes a plurality of ports;

a diaphragm in pressure communication with the pressure conduction catheter, the diaphragm configured to deform in response to changes in ICP at the plurality of ports; and

at least one sensor communicatively coupled to the processor and configured to obtain data indicative of the deformation of the diaphragm.

14. The apparatus of claim 13, wherein the implant body comprises the diaphragm.

18. The apparatus of claim 13, further comprising a barrier configured to cover the ports of the distal end of the pressure conduction catheter, wherein the barrier and pressure conduction catheter are filled with a predetermined number of gas molecules so that the barrier is not in tension in a predefined range of ICPs.

22. The apparatus of claim 18, wherein the predefined range of ICPs is −

100 mmHg to 150 mmHg.

25. The apparatus of claim 14, wherein the diaphragm and implant body are unibody.

26. The apparatus of claim 13, wherein the at least one standoff comprises a plurality of standoffs.

27. The apparatus of claim 26, wherein the plurality of standoffs are evenly spaced angularly about the central axis.

28. The apparatus of claim 27, wherein the plurality of standoffs are positioned radially a same distance from the central axis.

29. The apparatus of claim 13, wherein the at least one standoff comprises a projection extending circumferentially about the central axis.