Electromagnetic flow sensor device

• US 20050273014A1
• Filed: 06/06/2005
• Published: 12/08/2005
• Est. Priority Date: 06/04/2004
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Gianchandani, Yogesh B., Takahata, Kenichi
• Granted Patent: US 7,922,667 B2
• Time in Patent Office: Days
• US Class Current: 600/505
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0265 using electromagnetic means, e.g. electromagnetic flowmeter
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: A61B 5/6862 Stents
• CPC Class Codes: A61B 5/6876 Blood vessel
• CPC Class Codes: G01F 1/56 by using electric or magnetic effects G01F1/66 takes precedence
• CPC Class Codes: G01F 1/584 constructions of electrodes, accessories therefor
• CPC Class Codes: G01F 1/60 Circuits therefor

Abstract

Disclosed herein is an electromagnetic flow sensor device for monitoring flow of fluid in a channel. The sensor device includes a first electrode to be disposed along the channel and in communication with the fluid, a second electrode to be disposed along the channel and in communication with the fluid, and a radially expandable frame to structurally support the first electrode and the second electrode while conforming to the channel to position the first electrode and the second electrode along the channel. The device may also include an antenna coupled to the first and second electrodes to wirelessly provide an indication of a voltage induced between the first and second electrodes. In some embodiments, the radially expandable frame includes an insulating link such that the first and second electrodes are not electrically connected via the radially expandable frame. The sensor device may also include a structure having an inductance coupled to the first and second electrodes to wirelessly provide an indication of the induced voltage.

Claims

1. An electromagnetic flow sensor device for monitoring flow of fluid in a channel, comprising:

a first electrode to be disposed along the channel and in communication with the fluid;

a second electrode to be disposed along the channel and in communication with the fluid; and

a radially expandable frame to structurally support the first electrode and the second electrode while conforming to the channel to position the first electrode and the second electrode along the channel.

2. The electromagnetic flow sensor device of claim 1, wherein the fluid comprises blood and the channel comprises a blood vessel.

3. The electromagnetic flow sensor device of claim 2, further comprising a helical structure to be disposed in the blood vessel and having an inductance coupled to the first and second electrodes to wirelessly provide an indication of a voltage induced between the first and second electrodes.

4. The electromagnetic flow sensor device of claim 3, wherein the helical structure provides scaffolding support to the blood vessel as a stent.

5. The electromagnetic flow sensor device of claim 3, further comprising a voltage-controlled capacitor coupled to the inductance to form an LC tank.

6. The electromagnetic flow sensor device of claim 1, wherein the radially expandable frame includes at least one insulative portion such that the first electrode and the second electrode are not electrically connected via the radially expandable frame.

7. The electromagnetic flow sensor device of claim 1, wherein the radially expandable frame includes first and second meander bands having the first and second electrodes disposed therein, respectively, and wherein the first and second meander bands are structurally coupled by an insulating link.

8. The electromagnetic flow sensor device of claim 1, wherein the radially expandable frame comprises a C-shaped structure circumferentially disposed along the channel.

9. The electromagnetic flow sensor device of claim 1, wherein the radially expandable frame is disposed within the channel.

10. The electromagnetic flow sensor device of claim 1, wherein the radially expandable frame comprises a circular ring disposed along an interior wall of the channel.

11. The electromagnetic flow sensor device of claim 1, wherein:

the first and second electrodes comprise first and second conductive plates, respectively;

the radially expandable frame comprises a first pair of serpentine beams and a second pair of serpentine beams;

the first conductive plate and the first pair of serpentine beams form a first continuous conductive structure; and

,

the second conductive plate and the second pair of serpentine beams form a second continuous conductive structure.

12. The electromagnetic flow sensor device of claim 11, wherein the first and second pairs of serpentine beams plastically deform to position the first and second plates along an interior wall of the channel.

13. A device for monitoring blood flow in a blood vessel, the device comprising:

a radially expandable structure having a pair of electrodes and disposed within the blood vessel to position the pair of electrodes in the blood vessel for an electromagnetic measurement of the blood flow via a voltage induced across the pair of electrodes; and

,

an antenna coupled to the pair of electrodes to wirelessly provide an indication of the induced voltage.

14. The device of claim 13, wherein the radially expandable structure comprises a ring disposed along an interior wall of the blood vessel.

15. The device of claim 13, wherein the antenna is disposed in the blood vessel.

16. The device of claim 13, wherein the antenna comprises a stent having an inductance coupled to the pair of electrodes.

17. The device of claim 13, wherein the radially expandable structure includes a plurality of serpentine frame portions that are plastically deformable to expand such that the radially expandable structure conforms to an interior wall of the blood vessel.

18. The device of claim 17, wherein each serpentine frame portion of the plurality of serpentine frame portions is of unitary construction with one of the pair of electrodes.

19. The device of claim 17, wherein:

the plurality of serpentine frame portions comprises a conductive material; and

,

the radially expandable structure includes at least one insulating link such that the pair of electrodes are not electrically connected via the plurality of serpentine frame portions.

20. A blood flow sensor for monitoring blood flow in a blood vessel, the blood flow sensor comprising:

a pair of electrodes;

a pair of bands to structurally support the pair of electrodes wherein each band is extendible to position the pair of electrodes along the blood vessel; and

,

an insulating link to couple the pair of bands such that the pair of electrodes are not electrically connected via the pair of bands.

21. The blood flow sensor of claim 20, wherein each band comprises a unitary structure microfabricated from planar steel foil.

22. The blood flow sensor of claim 20, further comprising a further insulating link coupling the pair of unitary structures such that the blood flow sensor forms a ring-shaped frame that conforms to the blood vessel when implanted.

23. A device for monitoring blood flow in a blood vessel, the device comprising:

a pair of electrodes to be disposed in the blood vessel for an electromagnetic measurement of the blood flow via a voltage induced across the pair of electrodes by the blood flow; and

,

a structure to be disposed in the blood vessel and having an inductance coupled to the pair of electrodes to wirelessly provide an indication of the induced voltage.

24. The device of claim 23, wherein the structure provides support for the blood vessel as a stent.

25. The device of claim 23, further comprising a voltage-controlled capacitance.

26. The device of claim 23, further comprising a radially expandable frame to structurally support the pair of electrodes while conforming to the blood vessel to position the first electrode and the second electrode along the blood vessel.

27. The device of claim 26, wherein the radially expandable frame includes at least one insulative portion such that the pair of electrodes are not electrically connected via the radially expandable frame.

28. The device of claim 26, wherein the radially expandable frame comprises a circular ring disposed along an interior wall of the blood vessel.