Systems and Methods for Implanting Tissue Stimulation Electrodes in the Pelvic Region

• US 20080009914A1
• Filed: 07/10/2007
• Published: 01/10/2008
• Est. Priority Date: 07/10/2006
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Ams Research Corporation (Endo International PLC)
• Inventors: Mujwid, James R., Lund, Robert E., Gohman, James A., Buysman, John Jason
• Granted Patent: US 8,160,710 B2
• Time in Patent Office: Days
• US Class Current: 607/41
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0558 Anchoring or fixation means therefor

Abstract

Implantable medical devices to relieve problems associated with incontinence and related pelvic disorders and methods of implanting same are disclosed. Stimulation leads for placement in the pelvic floor have fixation mechanisms for stabilization of the stimulation electrodes to inhibit dislodgement from a selected stimulation site. In certain embodiments, the fixation mechanisms encourage fibrosis about the lead to chronically stabilize the position of the stimulation lead and/or stimulation electrode(s). In certain embodiments, the fixation mechanisms are isolated from body tissue during routing of the stimulation lead through a tissue pathway and then exposed to body tissue to encourage fibrosis.

Claims

1. A stimulation lead for placement in the pelvic floor and adapted to be coupled to an implantable pulse generator to deliver stimulation to a selected stimulation site comprising:

an elongated lead body extending between a lead body proximal end and a lead body distal end comprising an insulating sheath and at least one electrical conductor within the insulating sheath;

a proximal connector assembly having at least one lead connector element at the lead body proximal end coupled to a proximal end of the electrical conductor;

a stimulation electrode at the lead body distal end coupled to a distal end of the electrical conductor; and

a fixation mechanism extending along a portion of the lead body coupled to the insulating sheath and extending laterally away from the lead body, the fixation mechanism formed of a material encouraging tissue ingrowth along the length of the portion of the lead body to stabilize the stimulation electrode at the stimulation site.

2. The stimulation lead of claim 1, wherein the fixation mechanism comprises a sheet or tube of porous mesh having a mesh length and mesh width extending along the portion of the lead body.

3. The stimulation lead of claim 2, wherein the porous mesh is relatively flexible and defined by mesh edges that are stiffened to maintain the porous mesh sheet in a substantially planar shape.

4. The stimulation lead of claim 1, wherein the fixation mechanism extends along a portion of the lead body coupled to the insulating sheath intermediate the proximal connector assembly and the stimulation electrode.

5. The stimulation lead of claim 1, wherein the fixation mechanism extends along a portion of the lead body coupled to the insulating sheath from a point distal to the proximal connector assembly and to the stimulation electrode.

6. The stimulation lead of claim 1, wherein the fixation mechanism extends along a portion of the lead body coupled to the insulating sheath from a point distal to the proximal connector assembly and distal to the stimulation electrode.

7. The stimulation lead of claim 1, wherein the fixation mechanism extends along a portion of the lead body coupled to the insulating sheath from a point distal to the proximal connector assembly and distal to the stimulation electrode through a length that enables passage of the fixation mechanism around one of the urethra or anus and disposition of the stimulation electrode in operative relation to the urethra or anus.

8. The stimulation lead of claim 7, further comprising a tension control element extending at least through the portion of the fixation mechanism extending distally of the stimulation electrode.

9. The stimulation lead of claim 1, further comprising a protective sheath assembly enclosing the stimulation lead body and the fixation mechanism adapted to facilitate passage of the stimulation lead through a tissue pathway.

10. The stimulation of lead of claim 1, wherein the stimulation lead body has a body axis extending distally of the proximal lead connector assembly and a distal body segment extending laterally to the body axis disposing one or more stimulation electrode along the distal body segment.

11. A stimulation lead assembly for placement in the pelvic floor and adapted to be coupled to an implantable pulse generator to deliver stimulation to selected stimulation sites comprising:

a first stimulation lead comprising;

a first elongated lead body extending between a first lead body proximal end and a first lead body distal end comprising an insulating sheath and at least one electrical conductor within the insulating sheath;

a first proximal connector assembly having at least one lead connector element at the first lead body proximal end coupled to a proximal end of the electrical conductor;

a first stimulation electrode at the first lead body distal end coupled to a distal end of the electrical conductor; and

a first fixation mechanism extending along a portion of the lead body coupled to the insulating sheath and extending laterally away from the lead body, the fixation mechanism formed of a material encouraging tissue ingrowth along the length of the portion of the lead body to stabilize the stimulation electrode at the stimulation site; and

a second stimulation lead comprising;

a second elongated lead body extending between a second lead body proximal end and a second lead body distal end comprising an insulating sheath and at least one electrical conductor within the insulating sheath;

a second proximal connector assembly having at least one lead connector element at the second lead body proximal end coupled to a proximal end of the electrical conductor;

a second stimulation electrode at the second lead body distal end coupled to a distal end of the electrical conductor; and

a second fixation mechanism extending along a portion of the lead body coupled to the insulating sheath and extending laterally away from the lead body, the fixation mechanism formed of a material encouraging tissue ingrowth along the length of the portion of the lead body to stabilize the stimulation electrode at the stimulation site; and

interconnecting means for interconnecting the first and second lead body distal ends to enable disposition of the first and second stimulation electrodes in operative relation to first and second stimulation sites in the body.

12. The stimulation lead assembly of claim 11, wherein the interconnecting means further comprises a segment of lead body extending between the first and second stimulation electrodes providing a support function for body tissue in the pelvic region.

13. The stimulation lead assembly of claim 12, wherein the first and second fixation mechanisms extend along the segment of lead body extending between the first and second stimulation electrodes providing a support and fixation function for body tissue in the pelvic region.

14. The stimulation lead of claim 13, wherein the first and second fixation mechanisms comprises a sheet or tube of porous mesh having a mesh length and mesh width extending along the lead body.

15. The stimulation lead assembly of claim 11, wherein the interconnecting means further comprises an extension of the first and second fixation mechanisms between the first and second stimulation electrodes providing a support and fixation function for body tissue in the pelvic region.

16. The stimulation lead of claim 15, wherein the first and second fixation mechanisms comprises a sheet or tube of porous mesh having a mesh length and mesh width extending along the lead body.

17. The stimulation lead of claim 11, further comprising first and second protective sheath assemblies enclosing the respective first and second stimulation lead bodies and the at least portions of the first and second fixation mechanisms adapted to facilitate passage of the stimulation lead assembly through a tissue pathway.

18. A method of passing a stimulation lead having a stimulation lead body extending from a proximal lead connector end to a distal stimulation electrode through a tissue pathway to dispose the stimulation electrode in or adjacent a selected pelvic tissue structure of a patient, the lead body associated with a lead fixation mechanism extending along at least a portion of the lead body, the method comprising:

making a first skin incision through skin inferior to one of the anus or the urethra accessing one of the anal or urethral tissue structures;

making at least one second skin incision through the skin in an abdominal region of the patient'"'"'s body;

passing an implantation tool having first and second tool ends through the patient'"'"'s body between the first and second skin incisions to dispose the first tool end extending from one of the first and second skin incisions;

coupling the first tool end to the lead connector end;

manipulating the tool to draw the lead body and fixation mechanism through the tissue pathway and the lead connector end out of the other of the first and second skin incisions; and

positioning the stimulation electrode in relation to the pelvic tissue structure and the lead fixation mechanism in the tissue pathway to engage body tissue.

19. The method of claim 18, further comprising:

forming a subcutaneous tissue pocket proximate the abdominal skin incision;

coupling a stimulation implantable pulse generator to the lead connector end;

inserting the implantable pulse generator in the pocket; and

closing the pocket.

20. The method of claim 18, wherein the coupling step comprises:

providing a flexible tubular connector having a lumen extending between opposed first and second lumen ends; and

fitting the lead connector assembly into the first lumen end and the first tool end into the second lumen end.