Percutaneous Leads with Laterally Displaceable Portions, and Associated Systems and Methods

• US 20090299444A1
• Filed: 05/29/2008
• Published: 12/03/2009
• Est. Priority Date: 05/29/2008
• Status: Active Grant

• Current Assignee: Nevro Corporation
• Original Assignee: Nevro Corporation
• Inventors: Boling, C. Lance
• Granted Patent: US 8,108,052 B2
• Time in Patent Office: Days
• US Class Current: 607/118
• CPC Class Codes: A61N 1/0558 Anchoring or fixation means therefor

Abstract

Percutaneous leads with laterally displaceable sections, and associated systems and methods are disclosed. A device in accordance with a particular embodiment includes a lead body that in turn includes first, second and third percutaneous portions. The first portion can carry an electrical contact, the second portion can be spaced apart from the first portion, and the third portion can be positioned between the first and second portions along a deployment axis. The third portion can have a stiffness in a direction transverse to the deployment axis that is less than a stiffness of both the first and second portions transverse to the deployment axis, and a diameter that is less than corresponding diameters of the first and second portions.

Claims

1. A patient treatment device, comprising

a lead body that includes:

a first percutaneous portion carrying an electrode and having a first diameter;

a second percutaneous portion spaced apart from the first portion and having a second diameter; and

a third percutaneous portion positioned between the first and second portions along a deployment axis and having a third diameter less than the first and second diameters, the third portion having a stiffness in a direction transverse to the deployment axis that is less than a stiffness of the first portion transverse to the deployment axis, and less than a stiffness of the second portion transverse to the deployment axis.

2. The device of claim 1 wherein the third diameter is less than one quarter of the first diameter, and less than one quarter of the second diameter.

3. The device of claim 1 wherein the first portion has a uniform first diameter, and wherein the electrode is one of a plurality of electrodes exposed around a circumference of the first portion.

4. The device of claim 1 wherein the third portion includes a flexible electrical link that is coupled to the electrode and is unsupported between the first and second portions in a direction transverse to the deployment axis.

5. The device of claim 4 wherein the electrical link includes an insulated wire.

6. The device of claim 5, further comprising an axial reinforcing fiber arranged along the wire.

7. The device of claim 4 wherein the electrical link includes a ribbon of insulated wires.

8. The device of claim 4 wherein the second portion includes an electrical terminal, and wherein the electrical link is connected between the electrode and the electrical terminal.

9. The device of claim 1 wherein the lead body includes a first axial aperture extending into the first portion, and a second axial aperture extending entirely through the second portion.

10. The device of claim 9, further comprising a stylet removably received in the first and second apertures.

11. The device of claim 10 wherein the first portion and the stylet are releasably coupled with a bayonet fitting, and wherein the first portion and the stylet are separable from each other via relative twisting and axial movement between the stylet relative and the first portion.

12. The device of claim 9 wherein the third portion does not include an axial aperture.

13. The device of claim 1 wherein the electrode is one of multiple electrodes carried by the first portion, and wherein the third portion includes multiple flexible electrical links, with individual electrical links coupled to corresponding individual electrodes and with the individual electrical links unsupported between the first and second portions in a direction transverse to the deployment axis, the individual electrical links being movable relative to each other between the first and second portions.

14. The device of claim 1 wherein the first portion includes a fixation device positioned to fix the first portion relative to adjacent tissue.

15. The device of claim 14 wherein the fixation device includes a tine.

16. The device of claim 14 wherein the fixation device includes a proximally-facing cup positioned annularly around the first portion and extending radially outwardly from the first portion.

17. The device of claim 1 wherein the second portion includes a fixation device positioned to fix the second portion relative to adjacent tissue.

18. The device of claim 17 wherein the fixation device includes a suture.

19. A patient treatment device, comprising

a lead body that includes:

a first percutaneous portion carrying multiple electrodes;

a second percutaneous portion spaced apart from the first portion and carrying multiple terminals; and

a third percutaneous portion positioned between the first and second portions along a deployment axis, the third portion having a stiffness in a direction transverse to the deployment axis that is less than a stiffness of the first portion transverse to the deployment axis, and less than a stiffness of the second portion transverse to the deployment axis, the third portion including multiple individual wires coupled between individual electrodes and corresponding terminals, the individual wires being movable relative to each other at the third portion, wherein the third portion does not includes a shaft disposed around the individual wires.

20. The device of claim 19 wherein:

the first portion has a generally uniform first diameter;

the electrodes are generally cylindrical in shape and aligned along the deployment axis;

the second portion has a second generally uniform diameter equal to or approximately equal to the first diameter, and wherein the third portion has a third diameter less than both the first and second diameters.

21. The device of claim 19 wherein the first portion has a first convex rounded surface that intersects the deployment axis at the proximal end of the first portion, and wherein the second portion has a second convex rounded surface that intersects the deployment axis at the distal end of the second portion, the first and second convex rounded surfaces being positioned to be exposed to patient tissue after implantation.

22. A patient treatment device, comprising

a lead body that includes:

a first percutaneous portion carrying multiple electrodes and having a first aperture, the first portion having a first diameter and including a first tissue fixation element;

a second percutaneous portion spaced apart from the first portion, carrying multiple terminals and having a second aperture, the second portion having a second diameter and including a second tissue fixation element; and

a third percutaneous portion positioned between the first and second portions along a deployment axis, the third portion having a third diameter less than the first diameter and less than the second diameter, the third portion having a stiffness in a direction transverse to the deployment axis that is less than a stiffness of the first portion transverse to the deployment axis, and less than a stiffness of the second portion transverse to the deployment axis, the third portion including multiple individual wires coupled between individual electrodes and corresponding terminals, the individual wires being movable relative to each other at the third portion, wherein the third portion does not includes a shaft disposed around the individual wires; and

a delivery stylet extending through the second aperture and into the first aperture, with the individual wires arranged externally to the stylet between the first and second portions.

23. The device of claim 22 wherein the first portion includes a bayonet receptacle at a distal end of the first aperture, and the stylet includes a bayonet fitting, and wherein the bayonet fitting is releasably coupleable to the first portion by relative axial motion along the deployment axis and relative rotational motion about the rotational axis between the first portion and the stylet while the stylet is received in the first aperture.

24. A method for deploying a patient treatment device, comprising:

delivering a lead body into a patient'"'"'s body so that a first portion of the lead body having a first diameter and carrying an electrode is proximate to a spinal stimulation site, and so that a second portion of the lead body having a second diameter is positioned radially outwardly and spaced apart from the first portion, and so that a third portion of the lead body is positioned between the first and second portions, the third portion having a third diameter less than the first diameter and less than the second diameter; and

at least partially fixing the first portion, the second portion, or both the first and second portions to the patient'"'"'s body, while allowing the third portion to accommodate relative movement between the first and second portions.

25. The method of claim 24 wherein delivering the lead body includes positioning the first portion of the lead body within the spinal column and positioning the second portion of the lead body external to the spinal column.

26. The method of claim 24 wherein delivering the lead body includes positioning the electrode proximate to and in electrical communication with spinal cord neurons.

27. The method of claim 24 wherein delivering the lead body includes positioning the electrode proximate to and in electrical communication with dorsal root neurons.

28. The method of claim 24 wherein delivering the lead body includes positioning the electrode in a gutter along the spinal cord.

29. The method of claim 24 wherein delivering the lead body includes positioning the electrode at a dorsal root entry zone.

30. The method of claim 24, further comprising coupling the second portion of the lead body to an implanted electrical pulse generator.

31. The method of claim 24 wherein delivering the lead body includes positioning the first, second and third portions in a catheter, inserting the catheter into the patient'"'"'s body, and deploying the first, second and third portions from the catheter by pushing the portions out of the catheter with a stylet.

32. The method of claim 31, wherein the stylet is elongated along a longitudinal axis and includes a bayonet fitting, and wherein the method further comprises:

releasably engaging the stylet with the first portion of the lead body by inserting the stylet through the second portion and into the first portion, and rotating the stylet in a first direction about the longitudinal axis to engage the bayonet fitting with a corresponding bayonet receptacle in the first portion;

moving the lead body and the stylet together to position the lead body; and

when the lead body is in a target position, rotating the stylet in a second direction opposite the first direction to disengage the bayonet fitting from the bayonet receptacle, and withdrawing the stylet from the lead body.

33. The method of claim 24 wherein lead body is elongated along a deployment axis, the first portion has a first convex rounded surface that intersects the deployment axis at a proximal end of the first portion, and the second portion has a second convex rounded surface that intersects the deployment axis at a distal end of the second portion, and wherein the method further comprises exposing the first and second convex rounded surfaces to patient tissue as the lead body is implanted.