APPARATUS FOR IMPLANTING AN ELECTRICAL STIMULATION LEAD

• US 20080188916A1
• Filed: 04/04/2008
• Published: 08/07/2008
• Est. Priority Date: 08/08/2003
• Status: Active Grant

• Current Assignee: Peter B. Hegi, Terry Daglow, Thomas K. Hickman, Timothy S. Jones
• Original Assignee: Peter B. Hegi, Terry Daglow, Thomas K. Hickman, Timothy S. Jones
• Inventors: Jones, Timothy S., Hegi, Peter B., Hickman, Thomas K., Daglow, Terry
• Granted Patent: US 8,014,873 B2
• Time in Patent Office: Days
• US Class Current: 607/116
• CPC Class Codes: A61B 17/3401 Puncturing needles for the peridural or subarachnoid space or the plexus, e.g. for anaesthesia local anaesthesia A61M19/00
• CPC Class Codes: A61B 17/3415 for introducing tubes or catheters, e.g. gastrostomy tubes, drain catheters A61B17/3417 takes precedence; body piercing catheter guide needles A61M25/06
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/36021 for treatment of pain
• CPC Class Codes: A61N 1/36071 Pain

Abstract

In one embodiment, an introducer is provided for implanting an electrical stimulation lead to enable electrical stimulation of nerve tissue. The introducer includes an outer sheath and an inner penetrator. The outer sheath may accommodate insertion of the electrical stimulation lead and may be inserted into a human body near the nerve tissue. The inner penetrator is removably housed within the outer sheath and includes an inner channel configured to accommodate a guide wire, a tip end having a shape and size substantially conforming to that of the guide wire, a body region having a shape and size substantially conforming to that of the outer sheath, and one or more transition regions substantially connecting the tip end with the body region. At least a portion of the transition regions of the inner penetrator may flex to substantially follow flexures in the guide wire during advancement of the inner penetrator.

Claims

1. An introducer for implanting an electrical stimulation lead to enable electrical stimulation of nerve tissue, comprising:

an outer sheath to accommodate insertion of the electrical stimulation lead through the outer sheath, the outer sheath operable to be inserted into a human body near the nerve tissue; and

an inner penetrator removably housed within the outer sheath and comprising (i) an inner channel configured to accommodate a guide wire, (ii) a tip end having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the guide wire, (iii) a body region having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the outer sheath, and (iv) one or more transition regions substantially connecting the tip end with the body region;

wherein the inner penetrator is configured to be advanced along the guide wire to a desired location relative to the nerve tissue and removed from the outer sheath leaving the outer sheath substantially in position for insertion of the electrical stimulation lead through the outer sheath into position proximate the nerve tissue;

wherein the one or more transition regions include a tip transition region extending from the tip end of the inner penetrator at least a portion of the distance toward the body region of the inner penetrator, and during the advancement of the introducer along the guide wire, the tip transition region flexes to substantially follow flexures in the guide wire, the tip transition region being formed from a particular material and having a wall thickness that decreases toward the tip end of the inner penetrator.

2. The introducer of claim 1, wherein the cross-sectional shape and size of the tip end of the inner penetrator are significantly different than the cross-sectional shape and size of the body region of the inner penetrator.

3. The introducer of claim 1, wherein the outer sheath and the body region of the inner penetrator have substantially oval or oblong cross-sections, and the guide wire and the tip end of the inner penetrator have substantially circular cross-sections.

4. The introducer of claim 1, wherein the outer sheath and inner penetrator are configured from one or more flexible materials such that the introducer may flex to navigate around physical structures in the body.

5. The introducer of claim 1, wherein both the outer sheath and the inner penetrator are formed from one or more of plastic, silastic, or a polymeric materials.

6. The introducer of claim 1, wherein the one or more transition regions include a tip transition region extending from the tip end of the inner penetrator at least a portion of the distance toward the body region of the inner penetrator, the tip transition region being formed from a particular material and having a wall thickness sufficiently thin such that when the inner penetrator is advanced along the guide wire, the tip transition region may flex to substantially follow flexures in the guide wire.

7. The introducer of claim 6, wherein the wall thickness of tip transition region decreases toward the tip end of the inner penetrator

8. An introducer for implanting an electrical stimulation lead into the epidural space of a patient to enable electrical stimulation of nerve tissue, comprising:

an outer sheath to accommodate insertion of the electrical stimulation lead through the outer sheath, the outer sheath adapted for insertion into the epidural space of the patient; and

an inner penetrator removably housed within the outer sheath and comprising (i) an inner channel configured to accommodate a guide wire, (ii) a tip end having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the guide wire, (iii) a body region having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the outer sheath, and (iv) a plurality of flexing transition regions substantially connecting the tip end with the body region;

wherein at least a portion of the plurality of transition regions are adapted to flex to substantially follow flexures in the guide wire during advancement of the introducer along the guide wire;

wherein the outer sheath, the inner penetrator, and the plurality of transition regions allow the introducer, during entry within the epidural space, to assume a shape where a distal first portion of the introducer possesses a substantially linear shape within the epidural space and a second portion of the introducer exhibits a curve to allow the introducer to exit from the patient'"'"'s body.

9. The introducer of claim 8, wherein the introducer flexes to navigate around physical structures in the body during advancement of the introducer along the guide wire.

10. The introducer of claim 8, wherein:

the guide wire and the tip end of the inner penetrator have substantially circular cross-sections; and

the outer sheath and the body region of the inner penetrator have substantially oval cross-sections.

11. The introducer of claim 8, wherein:

the plurality of transition regions include a tip transition region extending from the tip end of the inner penetrator at least a portion of the distance toward the body region of the inner penetrator; and

during the advancement of the introducer along the guide wire, the tip transition region flexes to substantially follow flexures in the guide wire, the tip transition region being formed from a particular material and having a wall thickness that decreases toward the tip end of the inner penetrator.

12. The introducer of claim 8, wherein the plurality of transition regions include a tip transition region extending from the tip end of the inner penetrator at least a portion of the distance toward the body region of the inner penetrator, the tip transition region having a substantially circular cross-section extending along the length of the tip transition region, the substantially circular cross-section having an inner diameter and an outer diameter, both the inner diameter and the outer diameter of the substantially circular cross-section tapering toward the tip end of the tip transition region.

13. The introducer of claim 8, wherein the plurality of transition regions include a tip transition region, a body transition region, and a middle transition connecting the tip transition region with the body transition region, the tip transition region and the body transition region being tapered, and the middle transition not being tapered.

14. An introducer for implanting an electrical stimulation lead to enable electrical stimulation of nerve tissue, comprising:

an outer sheath to accommodate insertion of the electrical stimulation lead through the outer sheath, the outer sheath adapted for insertion into a human body near nerve tissue; and

an inner penetrator removably housed within the outer sheath and comprising (i) an inner channel configured to accommodate a guide wire, (ii) a tip end having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the guide wire, (iii) a body region having a cross-sectional shape and size substantially conforming to a cross-sectional shape and size of the outer sheath, and (iv) a plurality of flexing transition regions substantially connecting the tip end with the body region;

wherein the tip end of the inner penetrator comprises (i) a needle nose segment that possesses an approximately constant outer diameter, the needle nose segment comprising an aperture for providing an interference fit with the guide wire and (ii) a transition segment that transitions from the shape of the needle nose segment to the shape of the body portion of the inner penetrator.

15. The introducer claim 14 wherein the needle nose segment is more flexible than the transition segment and the transition segment is more flexible than the body portion of the inner penetrator.