Flexible tube sensor for sensing urinary sphincter pressure

• US 20060247723A1
• Filed: 04/28/2005
• Published: 11/02/2006
• Est. Priority Date: 04/28/2005
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Gerber, Martin T., Miesel, Keith A.
• Granted Patent: US 8,068,910 B2
• Time in Patent Office: Days
• US Class Current: 607/41
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• 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 5/202 Assessing bladder functions, e.g. incontinence assessment
• CPC Class Codes: A61B 5/205 Determining bladder or urethral pressure
• CPC Class Codes: A61B 5/6882 Anchoring means
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control

Abstract

The disclosure describes a therapeutic sphincter control system with a fluid tube pressure sensor. The system senses sphincter pressure and sends the information to a stimulator that is capable of stimulation therapy to control sphincter contractility, thus reducing unwanted urinary incontinence. Measuring sphincter pressure is accomplished through the use of a fluid-filled tube placed through the sphincter and attached to a module implanted within the bladder. Pressure within the tube is transduced to generate an electrical signal that is sent wirelessly to an implanted stimulator connected to a lead positioned near pelvic floor nerves. An external device may be used to wirelessly send information to the implanted stimulator and inhibit stimulation in order for the patient to empty the bladder. Pressure information and stimulation information may be recorded and reviewed for continued patient monitoring. In addition, the system may only include the pressure sensor to monitor patient pressure information.

Claims

1. An implantable electrical stimulation system comprising:

an implantable pressure sensor including a flexible tube containing fluid and a sensing element that senses a pressure level exerted by a sphincter within a patient based on a pressure level of the fluid when the tube is placed proximate to the sphincter; and

an implantable stimulator that delivers electrical stimulation to the patient based on the sensed pressure level.

2. The system of claim 1, wherein the flexible tube includes a closed end and an open end, and the sensing element is disposed at the open end.

3. The system of claim 2, wherein the sensing element includes a flexible membrane that generates an electrical signal based on deformation of the membrane by pressure within the flexible tube.

4. The system of claim 3, wherein the flexible membrane includes a strain gauge sensor.

5. The system of claim 1, wherein the flexible tube has a length of less than approximately 7 cm and an outer diameter of approximately 1 to 3 mm.

6. The system of claim 1, wherein the implantable pressure sensor includes a fixation mechanism to position the flexible tube proximate the urinary sphincter within the patient.

7. The system of claim 6, wherein the implantable pressure sensor includes a housing, the tube extending from the housing, and the fixation mechanism is positioned to attach the housing to an inner wall of a bladder of the patient.

8. The system of claim 1, wherein the implantable sensor includes a telemetry circuit that transmits information based on the sensed pressure level.

9. The system of claim 8, wherein the telemetry circuit transmits the information to the implantable stimulator, the implantable stimulator adjusting one or more parameters of the electrical stimulation based on the transmitted information.

10. The system of claim 9, further comprising an external programmer to adjust stimulation parameters associated with the electrical stimulation delivered by the implantable stimulator, wherein the telemetry circuit transmits the information to the external programmer.

11. The system of claim 1, wherein the implantable stimulator includes a lead carrying one or more electrodes to deliver electrical stimulation to a nerve site that innervates the urinary sphincter.

12. The system of claim 1, wherein the implantable sensor includes a plurality of implantable sensors having flexible tubes disposed at different positions within the urinary tract.

13. The system of claim 1, wherein the implantable pressure sensor includes a sensor housing, wherein the flexible tube extends from the sensor housing, the system further comprising a cystoscopic deployment device to deploy the implantable pressure sensor, the deployment device defining a cavity to carry the sensor housing and a channel to accommodate the flexible tube extending from the housing.

14. The system of claim 1, wherein the sensing element senses a pressure level exerted by a urinary sphincter within the patient, and the implantable stimulator provides electrical stimulation to control urinary incontinence.

15. A method comprising:

sensing a pressure level exerted by a urinary sphincter within a patient based on a pressure of fluid within a flexible tube placed proximate to the urinary sphincter; and

delivering electrical stimulation to the patient based on the sensed pressure level.

16. The method of claim 15, wherein the flexible tube includes a closed end and an open end, and sensing a pressure level includes sensing the pressure level via a sensing element disposed at the open end.

17. The method of claim 16, wherein the sensing element includes a flexible membrane that generates an electrical signal based on deformation of the membrane by pressure within the flexible tube.

18. The method of claim 17, wherein the flexible membrane includes a strain gauge sensor.

19. The method of claim 15, wherein the flexible tube has a length of less than approximately 7 cm and an outer diameter of approximately 1 to 3 mm.

20. The method of claim 15, wherein the pressure sensor includes a housing, the tube extending from the housing, and the method further comprises fixing the housing to an inner wall of a bladder of the patient.

21. The method of claim 15, further comprising transmitting information based on the sensed pressure level from the sensor via wireless telemetry.

22. The method of claim 21, further comprising transmitting the information to an implantable stimulator, wherein the implantable stimulator adjusts one or more parameters of the electrical stimulation based on the transmitted information.

23. The method of claim 22, further comprising transmitting the information to an external programmer, wherein the external programmer adjusts one or more parameters of the electrical stimulation delivered by the implantable stimulator based on the transmitted information.

24. The system of claim 15, further comprising sensing a pressure level exerted by a urinary sphincter within the patient, and delivering the electrical stimulation to control urinary incontinence.

25. An implantable pressure sensor comprising:

a flexible tube containing fluid;

a sensing element that senses a pressure level of the fluid within the flexible tube; and

a fixation mechanism to position the flexible tube proximate a sphincter within a patient.

26. The sensor of claim 25, further comprising a processor that determines a pressure level of the sphincter based on the sensed pressure level.

27. The sensor of claim 25, wherein the flexible tube includes a closed end and an open end, and the sensing element is disposed at the open end.

28. The sensor of claim 27, wherein the sensing element includes a flexible membrane that generates an electrical signal based on deformation of the membrane by pressure within the flexible tube.

29. The sensor of claim 25, wherein the flexible tube has a length of less than approximately 7 cm and an outer diameter of approximately 1 to 3 mm.

30. The sensor of claim 25, wherein the implantable pressure sensor includes a housing, the tube extending from the housing, and the fixation mechanism is positioned to attach the housing to an inner wall of a bladder of the patient.