Percutaneous lead introducer

• US 8,909,353 B2
• Filed: 02/13/2013
• Issued: 12/09/2014
• Est. Priority Date: 08/29/2003
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Harris, Charmaine K., Klein, Joseph J.
• Primary Examiner(s): Alter, Alyssa M
• Application Number:
  US13/766,601
• Publication Number:
  US 20130158564A1
• Time in Patent Office: 664 Days
• Field of Search: 607/115, 607/116, 607/117, 606/194, 606/129, 600/594, 600/16
• US Class Current: 607/116
• CPC Class Codes: A61B 17/34 Trocars; Puncturing needles pointed biopsy instruments A61B10/0233; devices for piercing the ear-lobes A44C7/001; seals or hemostasis valves A61M39/06
• 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 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61M 25/0102 Insertion or introduction using an inner stiffening member, e.g. stylet or push-rod
• CPC Class Codes: A61M 25/06 Body-piercing guide needles or the like
• CPC Class Codes: A61M 25/0662 Guide tubes
• CPC Class Codes: A61M 29/00 Dilators with or without means for introducing media, e.g. remedies instruments for performing visual medical inspections of cavities or tubes of the body A61B1/00
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy

Abstract

In general, the invention is directed to a technique for percutaneously introducing a stimulation lead into a target stimulation site via the epidural region proximate the spine of a patient. The process of introducing the stimulation lead may include the use of a hollow stimulation lead introducer, which comprises an elongated sheath and an elongated dilator. The dilator fits within the sheath and serves to widen a path through the epidural region for the introduction of a stimulation lead. At least a portion of the stimulation lead introducer has an oblong cross-section, allowing passage of stimulation leads such as paddle leads. The stimulation lead introducer may enter the epidural region proximate a spine of a patient via a guidewire. The stimulation lead introducer provides a path through the epidural region of a patient to a target stimulation site. A stimulation lead may travel through the path to reach the target stimulation site where it may provide therapy to the patient.

Claims

1. A stimulation lead introducer for facilitating implantation of a lead, the stimulation lead introducer comprising:

an elongated dilator defining a dilator lumen sized to advance over a guidewire, the dilator having a substantially deformable distal tip, wherein a distal portion of the distal tip has a substantially circular cross-section, whereas a more proximal portion of the distal tip has a substantially oblong cross-section sized to widen a path through an epidural region proximate a spine of a patient by following the guidewire through the epidural region proximate the spine of the patient, wherein the widened path facilitates advancement of the lead through the epidural region proximate the spine of the patient; and

an elongated sheath defining a sheath lumen, wherein the sheath comprises a sheath material that is substantially deformable, wherein at least a portion of the sheath lumen provides a substantially oblong cross-section sized to accommodate the dilator, wherein the sheath is configured to facilitate advancement of the lead along a portion of the path when the dilator is not present in the sheath, wherein the dilator is configured to extend beyond a distal end of the sheath lumen.

2. The stimulation lead introducer of claim 1, wherein the dilator distal tip tapers from the substantially oblong cross-section at the more proximal portion of the distal tip to the substantially circular cross-section at the distal portion of the distal tip.

3. The stimulation lead introducer of claim 1, wherein an outer surface of the sheath has a substantially oblong cross-section with a width of the cross-section of the sheath that is greater than approximately two times a height of the cross-section of the sheath.

4. The stimulation lead introducer of claim 1, wherein the sheath material is substantially elastically deformable.

5. The stimulation lead introducer of claim 1, wherein the distal tip is selectably deformable to hold a shape.

6. The stimulation lead introducer of claim 1, wherein a distal opening to the dilator lumen is substantially circular to fit around the guidewire.

7. The stimulation lead introducer of claim 1, wherein a width of an outside of the sheath is within a range from approximately 5.21 millimeters to approximately 7.75 millimeters, and a height of the outside of the sheath is within a range from approximately 3.05 millimeters to approximately 3.56 millimeters.

8. The stimulation lead introducer of claim 1, wherein the deformable properties of the distal tip of the dilator decrease the probability of causing a cerebral spinal fluid leak from a puncture in a dura membrane as the dilator widens the path through the epidural region proximate the spine of the patient.

9. The stimulation lead introducer of claim 1, wherein the sheath is configured to maintain the path in the epidural region for advancement of the stimulation lead to a target site via the sheath after withdrawal of the dilator from the sheath lumen.

10. A method for introducing a stimulation lead comprising:

inserting a needle into an epidural region proximate a spine of a patient;

inserting a guidewire into the needle such that a distal end of the guidewire extends within the epidural region proximate the spine of the patient;

withdrawing the needle over the guidewire from the epidural region of the patient;

inserting a stimulation lead introducer to a target site within the epidural region proximate the spine of the patient via the guidewire following withdrawal of the needle, the stimulation lead introducer widening a path created by the needle to have a substantially oblong cross-section, wherein the introducer includes;

an elongated dilator defining a dilator lumen sized to advance over a guidewire, the dilator having a substantially deformable distal tip, wherein a distal portion of the distal tip has a substantially circular cross-section, whereas a more proximal portion of the distal tip has a substantially oblong cross-section sized to widen a path through an epidural region proximate a spine of a patient by following the guidewire through the epidural region proximate the spine of the patient, wherein the widened path facilitates advancement of the lead through the epidural region proximate the spine of the patient; and

an elongated sheath defining a sheath lumen, wherein the sheath comprises a sheath material that is substantially deformable, wherein at least a portion of the sheath lumen provides a substantially oblong cross-section sized to accommodate the dilator, wherein the sheath is configured to facilitate advancement of the lead along a portion of the path when the dilator is not present in the sheath;

withdrawing the guidewire from the epidural region proximate the spine of the patient;

withdrawing the dilator from the sheath; and

introducing the stimulation lead within the epidural region proximate the spine of the patient via the sheath following withdrawal of the dilator and the guidewire.

11. The method of claim 10, further comprising attaching a syringe to the needle, prior to inserting the guidewire into the needle, and attempting to inject fluid into the epidural region proximate the spine of the patient via the syringe and the needle to evaluate a position of the needle.

12. The method of claim 10, further comprising activating the stimulation lead to stimulate a nerve after introducing the stimulation lead within the epidural region proximate the spine of the patient.

13. The method of claim 10, wherein the dilator distal tip tapers from the substantially oblong cross-section at the more proximal portion of the distal tip to the substantially circular cross-section at the distal portion of the distal tip.

14. The method of claim 10, wherein an outer surface of the sheath has a substantially oblong cross-section with a width of the cross-section of the sheath that is greater than approximately two times a height of the cross-section of the sheath.

15. The method of claim 10, wherein the distal tip is selectably deformable to hold a shape.

16. The method of claim 10, wherein a width of an outside of the sheath is within a range from approximately 5.21 millimeters to approximately 7.75 millimeters, and a height of the outside of the sheath is within a range from approximately 3.05 millimeters to approximately 3.56 millimeters.

17. A kit for implanting a lead proximate a spine of a patient via a path through the epidural region proximate the spine, the kit comprising:

a needle configured for insertion into the epidural region proximate the spine of the patient;

a guidewire sized to pass through a lumen of the needle and into the epidural region proximate the spine of the patient; and

a stimulation lead introducer, wherein the stimulation lead introducer includes;

an elongated dilator defining a dilator lumen sized to advance over the guidewire, the dilator having a substantially deformable distal tip, wherein a distal portion of the distal tip has a substantially circular cross-section, whereas a more proximal portion of the distal tip has a substantially oblong cross-section sized to widen a path through an epidural region proximate a spine of a patient by following the guidewire through the epidural region proximate the spine of the patient, wherein the widened path facilitates advancement of the lead through the epidural region proximate the spine of the patient; and

an elongated sheath defining a sheath lumen, wherein the sheath comprises a sheath material that is substantially deformable, wherein at least a portion of the sheath lumen provides a substantially oblong cross-section sized to accommodate the dilator, wherein the sheath is configured to facilitate advancement of the lead along a portion of the path when the dilator is not present in the sheath.

18. The kit of claim 17, wherein the needle is a Tuohy needle.

19. The kit of claim 17, further comprising a stylet sized to fit inside the needle lumen to prevent coring of tissue when the needle is inserted into a patient.

20. The kit of claim 17, wherein the dilator distal tip tapers from the substantially oblong cross-section at the more proximal portion of the distal tip to the substantially circular cross-section at the distal portion of the distal tip.