INSULATOR LAYERS FOR LEADS OF IMPLANTABLE ELECTRIC STIMULATION SYSTEMS AND METHODS OF MAKING AND USING

• US 20100256693A1
• Filed: 04/07/2009
• Published: 10/07/2010
• Est. Priority Date: 04/07/2009
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: McDonald, Matthew Lee, Pianca, Anne Margaret, Venook, Ross Daniel
• Granted Patent: US 8,478,423 B2
• Time in Patent Office: Days
• US Class Current: 607/2
• 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 1/086 Magnetic resonance imaging [MRI] compatible leads
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

An implantable lead includes a plurality of conductors disposed in an elongated member. At least one of the conductors includes at least one unit that includes a first conductor segment extending along the elongated member from a beginning point to a first position, a second conductor segment extending along the elongated member from the first position to a second position, and a third conductor segment extending from the second position to an endpoint. An inner insulator layer is disposed along at least a portion of the elongated member and is formed of a material that is flowable to fill in at least some open spaces between portions of at least one of the units. An outer insulator layer is disposed over at least a portion of the inner insulator layer. The outer insulator layer has at least one physical characteristic different from the inner insulator layer.

Claims

1. An implantable lead comprising:

an elongated member having a distal end, a proximal end, and a longitudinal length;

a plurality of electrodes disposed on the distal end of the elongated member;

a plurality of terminals disposed on the proximal end of the elongated member;

a plurality of conductors, each conductor electrically coupling at least one of the electrodes to at least one of the terminals, wherein at least one of the conductors comprises at least one unit, the at least one unit comprising

a first conductor segment extending along the elongated member from a beginning point to a first position,

a second conductor segment extending along the elongated member from the first position to a second position, and

a third conductor segment extending along the elongated member from the second position to an endpoint,

wherein the first position is between the second position and the endpoint, and the second position is between the beginning point and the first position;

an inner insulator layer disposed along at least a portion of the elongated member, wherein the inner insulator layer is formed of a material that is flowable when applied to the conductors to fill in at least some open spaces between portions of at least one of the units; and

an outer insulator layer disposed over at least a portion of the inner insulator layer, wherein the outer insulator layer has at least one physical characteristic that is different from the inner insulator layer.

2. The lead of claim 1, wherein the insulator layers are configured and arranged to alter one or more of the capacitance, the inductance, or the dielectric properties of the lead.

3. The lead of claim 1, wherein a conductor insulation is disposed over at least a portion of at least one of the plurality of conductors, the conductor insulation disposed between the conductor and the inner insulator layer.

4. The lead of claim 1, wherein the inner insulator layer is configured and arranged to set or cross-link when cooled after flowing.

5. The lead of claim 1, further comprising at least one additional insulator layer.

6. The lead of claim 1, wherein each of the conductor segments is coiled.

7. The lead of claim 1, wherein the physical composition of the material used to form at least one of the inner insulator layer or the outer insulator layer varies along the longitudinal length of the elongated member.

8. The lead of claim 1, further comprising a conductor placement sleeve disposed in the elongated member and extending along at least a portion of the longitudinal length of the elongated member, wherein the plurality of conductors are disposed over the conductor placement sleeve.

9. The lead of claim 8, wherein the inner insulator material is configured and arranged to couple with the conductor placement sleeve.

10. The lead of claim 1, wherein at least one of the inner insulator layer or the outer insulator layer comprises at least one of silicone elastomer, a thermoplastic polymer, a composite material, a doped material, a thermoset polymer, or a foam.

11. The lead of claim 1, wherein the outer insulator layer forms an outer surface along at least a portion of the longitudinal length of the elongated member such that the elongated member has a uniform transverse diameter.

12. The lead of claim 1, wherein the outer insulator layer differs from the inner insulator layer by one or more of flexibility, melting point, viscosity, or rigidity.

13. The lead of claim 1, wherein the outer insulator layer is formed from a different material than the inner insulator layer.

14. An electrical stimulating system comprising:

a lead having a distal end, a proximal end, and a longitudinal length;

a plurality of electrodes disposed on the distal end of the lead;

a plurality of terminals disposed on the proximal end of the lead;

a plurality of conductors, each conductor electrically coupling at least one of the electrodes to at least one of the terminals, wherein at least one of the conductors comprises at least one unit, the at least one unit comprising

a first conductor segment extending along the lead from a beginning point to a first position,

a second conductor segment extending along the lead from the first position to a second position, and

a third conductor segment extending along the lead from the second position to an endpoint,

wherein the first position is between the second position and the endpoint, and the second position is between the beginning point and the first position;

an inner insulator layer disposed along at least a portion of the lead, wherein the inner insulator layer is formed of a material that is flowable when applied to the conductors to fill in at least some open spaces between portions of at least one of the units; and

an outer insulator layer disposed over at least a portion of the inner insulator layer, wherein the outer insulator layer has at least one physical characteristic that is different from the inner insulator layer;

a control module configured and arranged to electrically couple to the proximal end of the lead, the control module comprising

a housing, and

an electronic subassembly disposed in the housing; and

a connector for receiving the lead, the connector having a proximal end, a distal end, and a longitudinal length, the connector configured and arranged to receive the lead, the connector comprising

a connector housing defining a port at the distal end of the connector, the port configured and arranged for receiving the proximal end of the lead, and

a plurality of connector contacts disposed in the connector housing, the connector contacts configured and arranged to couple to at least one of the plurality of terminals disposed on the proximal end of the lead.

15. The electrical stimulating system of claim 14, wherein the connector is disposed on the control module.

16. The electrical stimulating system of claim 14, further comprising a lead extension having a proximal end and a distal end, the connector disposed on the distal end of the lead extension.

17. The electrical stimulating system of claim 16, wherein the proximal end of the lead extension is configured and arranged for insertion into another connector.

18. The electrical stimulating system of claim 16, wherein the lead extension has a distal end, a proximal end, and a longitudinal length, the lead extension comprising a plurality of conductive contacts disposed on the distal end of the lead extension;

a plurality of terminals disposed on the proximal end of the lead extension;

a plurality of conductors, each conductor electrically coupling at least one of the conductive contacts to at least one of the terminals, wherein at least one of the conductors comprises at least one unit, the at least one unit comprising

a first conductor segment extending along the lead extension from a beginning point to a first position,

a second conductor segment extending along the lead from the first position to a second position, and

a third conductor segment extending along the lead from the second position to an endpoint,

wherein the first position is between the second position and the endpoint, and the second position is between the beginning point and the first position;

an inner insulator layer disposed along at least a portion of the lead extension, wherein the inner insulator layer is formed of a material that is flowable when applied to the conductors to fill in at least some open spaces between portions of at least one of the units; and

an outer insulator layer disposed over at least a portion of the inner insulator layer, wherein the outer insulator layer has at least one physical characteristic that is different from the inner insulator layer.

19. A method for forming an implantable lead, the method comprising:

forming an elongated conductor into at least one unit, the at least one unit comprising

a first conductor segment extending in a first direction from a beginning point to a first position,

a second conductor segment extending in a second direction that is opposite to the first direction from the first position to a second position, and

a third conductor segment extending in the first direction from the second position to an endpoint;

disposing an inner insulator layer over at least a portion of the conductor, wherein the inner insulator layer is flowable when applied over the conductor to fill in at least some open spaces between portions of the at least one unit; and

disposing an outer insulator layer over at least a portion of the inner insulator layer, wherein the outer insulator has at least one physical characteristic that is different from the inner insulator layer;

coupling a first end of the conductor to an electrode; and

coupling a second end of the conductor to a terminal.

20. The method of claim 19, wherein disposing the inner insulator layer over at least a portion of the conductor comprises filling in at least some open spaces formed between the conductor segments.