Miniature implantable neurostimulator system for sciatic nerves and their branches

• US 9,913,980 B2
• Filed: 02/03/2017
• Issued: 03/13/2018
• Est. Priority Date: 08/17/2014
• Status: Active Grant

• Current Assignee: Coloplast A/S
• Original Assignee: Nine Continents Medical, Inc. (Coloplast A/S)
• Inventors: Ostroff, Alan, Jacobson, Peter
• Primary Examiner(s): FAIRCHILD, MALLIKA DIPAYAN
• Application Number:
  US15/424,683
• Publication Number:
  US 20170173328A1
• Time in Patent Office: 403 Days
• CPC Class Codes: A61N 1/0556 Cuff electrodes
• CPC Class Codes: A61N 1/0558 Anchoring or fixation means therefor
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control
• CPC Class Codes: A61N 1/36057 adapted for stimulating afferent nerves
• CPC Class Codes: A61N 1/3606 adapted for a particular treatment
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/36171 Frequency
• CPC Class Codes: A61N 1/36175 Pulse width or duty cycle
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3758 Packaging of the components within the casing
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

This application describes a miniature implantable neurostimulator system for sciatic nerves and their branches. The implanted miniature neurostimulator is implanted in the leg and stimulates these nerves for the treatment of urinary or bowel incontinence. The miniature implantable neurostimulator has a low duty cycle permitting a small size with medically-acceptable longevity. The system includes a wireless programmer and patient-activated key fob.

Claims

1. A method for improving a urinary or bowel function in a subject, the method comprising:

creating an incision in a leg of the subject to access a stimulation site;

placing an implant at or near the stimulation site through the incision; and

positioning at least a portion of an electrode assembly of the implant at or adjacent a sciatic nerve or a branch thereof in the stimulation site,

wherein the electrode assembly of the implant directs a stimulation signal to tissue of the subject, the stimulation signal improving a urinary or bowel function in the subject,

wherein the stimulation signal is directed with a duty cycle of between 0.1% and 2.5% and a total average current drain from a battery of the implant of between 0.1 μ

A and 5 μ

A, the total average current drain comprising a background current, plus a stimulation signal current weighted by the duty cycle, and

wherein the background current, the stimulation signal current, and the duty cycle combine to provide a useful life of the implant in a body of the subject of at least 5 years without removal from the body.

2. The method of claim 1, wherein the stimulation signal is configured to treat urinary or bowel incontinence.

3. The method of claim 1, wherein creating the incision in the leg comprises creating a tunnel in the leg for the implant.

4. The method of claim 3, wherein creating the tunnel in the leg for the implant comprises creating a first tunnel from the incision into the tissue and creating a second tunnel from the incision into the tissue, wherein placing the implant at or near the stimulation site comprises placing an enclosure of the implant into the first tunnel, and wherein positioning the electrode assembly of the implant at or adjacent a sciatic nerve or a branch thereof comprises positioning at least a portion of the electrode assembly in the second tunnel.

5. The method of claim 4, wherein the first tunnel is created in a first direction and the second tunnel is created in a second direction opposite the first direction.

6. The method of claim 1, wherein creating the incision in the leg comprises creating a primary incision in the leg to access the stimulation site, creating a secondary incision in the leg, and creating a tunnel in the leg between the primary and secondary incisions.

7. The method of claim 1, further comprising, prior to placing the implant at or near the stimulation site, qualifying the subject for use of the implant prior to the electrode assembly directing the stimulation signal to the tissue of the subject.

8. The method of claim 1, wherein the useful life of the implant implanted in the body is in a range between 5 and 35 years, 6 and 34 years, 7 and 33 years, 8 and 32 years, 9 and 31 years, 10 and 30 years, 11 and 29 years, 12 and 28 years, 13 and 27 years, 14 and 26 years, 15 and 25 years, 16 and 24 years, 17 and 23 years, 18 and 22 years, or 19 and 21 years.

9. The method of claim 1, wherein the duty cycle of the stimulation signal is in a range between 2.4% and 0.1%, 2.3% and 0.1%, 2.2% and 0.1%, 2.1% and 0.1%, 2.0% and 0.1%, 1.9% and 0.1%, 1.8% and 0.1%, 1.7% and 0.1%, 1.6% and 0.1%, 1.5% and 0.1%, 1.4% and 0.1%, 1.3% and 0.1%, 1.2% and 0.1%, 1.1% and 0.1%, 1.0% and 0.1%, 0.9% and 0.1%, 0.8% and 0.1%, 0.7% and 0.1%, 0.6% and 0.1%, 0.5% and 0.1%, 0.4% and 0.1%, 0.3% and 0.1%, or 0.2% and 0.1%.

10. The method of claim 1, wherein the electrode assembly of the implant directs the stimulation signal to the tissue of the subject for 30 minutes once a week.

11. The method of claim 1, wherein the electrode assembly of the implant directs the stimulation signal to the tissue of the subject while the subject is asleep.

12. The method of claim 1, wherein the background current is in a range of between 4.5 μ

A and 0.10 μ

A, 4.0 μ

A and 0.10 μ

A, 3.5 μ

A and 0.10 μ

A, 3.0 μ

A and 0.10 μ

A, 2.5 μ

A and 0.10 μ

A, 2.0 μ

A and 0.10 μ

A, 1.5 μ

A and 0.10 μ

A, 1.0 μ

A and 0.10 μ

A, 0.9 μ

A and 0.10 μ

A, 0.8 μ

A and 0.10 μ

A, 0.7 μ

A and 0.10 μ

A, 0.6 μ

A and 0.10 μ

A, 0.5 μ

A and 0.10 μ

A, 0.4 μ

A and 0.10 μ

A, 0.3 μ

A and 0.10 μ

A, or 0.2 μ

A and 0.1 μ

A.

13. The method of claim 1, wherein the stimulation signal has a stimulation pulse current in a range between 19 mA and 1 mA, 18 mA and 2 mA, 17 mA and 3 mA, 16 mA and 4 mA, 15 mA and 5 mA, 14 mA and 6 mA, 13 mA and 7 mA, 12 mA and 8 mA, or 11 mA and 9 mA.

14. The method of claim 1, wherein the stimulation signal has a stimulation frequency in a range between 30 Hz and 10 Hz, 29 Hz and 11 Hz, 28 Hz and 12 Hz, 27 Hz and 13 Hz, 26 Hz and 14 Hz, 25 Hz and 15 Hz, 24 Hz and 16 Hz, 23 Hz and 17 Hz, 22 Hz and 18 Hz, or 21 Hz and 19 Hz.

15. The method of claim 1, wherein the stimulation signal has a stimulation pulse width in a range between 300 μ

s and 100 μ

s, 290 μ

s and 110 μ

s, 280 μ

s and 120 μ

s, 270 μ

s and 130 μ

s, 260 μ

s and 140 μ

s, 250 μ

s and 150 μ

s, 240 μ

s and 160 μ

s, 230 μ

s and 170 μ

s, 220 μ

s and 180 μ

s, or 210 μ

s and 190 μ

s.

16. The method of claim 1, wherein the implant has a size such that it is implanted in the body of the subject with minimal long-term discomfort.

17. The method of claim 16, wherein a total volume of the implant is in a range between 1.9 cc and 0.1 cc, 1.8 cc and 0.2 cc, 1.7 cc and 0.3 cc, 1.6 cc and 0.4 cc, 1.5 cc and 0.5 cc, 1.4 cc and 0.6 cc, 1.3 cc and 0.7 cc, 1.2 cc and 0.8 cc, or 1.1 cc and 0.9 cc.

18. The method of claim 1, further comprising wirelessly recharging the battery.

19. The method of claim 1, further comprising anchoring one or more of a housing of the implant or the electrode array into the tissue with a fixation element of the housing or electrode array.

20. The method of claim 19, wherein the fixation element comprises a hook, a pin, a screw, a pigtail screw, a ring, a grasper, or a suture.

21. The method of claim 1, further comprising communicating, with an external programmer, with a wireless communication transceiver of the implant.

22. The method of claim 1, wherein the implant is configured to detect a magnetic field.

23. The method of claim 22, wherein generation of the stimulation signal is postponed, disabled, or otherwise modified in response to the detected magnetic field.

24. The method of claim 23, wherein the magnetic field is generated from an external programmer to communicate with circuitry of the implant.

25. The method of claim 23, wherein the magnetic field is detected with a magnetic field sensor.

26. The method of claim 25, wherein the magnetic field sensor comprises a giant magnetoresistance (GMR) switch.

27. The method of claim 1, further comprising detecting an orientation or alignment of the implant.

28. The method of claim 27, wherein the orientation or alignment of the implant or a movement of the subject is detected with an accelerometer of the implant.

29. The method of claim 28, wherein generation of the stimulation signal is disabled, postponed, or otherwise modified in response to the detected orientation or movement.