Implantable Lead Affixation Structure for Nerve Stimulation to Alleviate Bladder Dysfunction and Other Indication

• US 20180078760A1
• Filed: 09/28/2017
• Published: 03/22/2018
• Est. Priority Date: 08/15/2014
• Status: Active Grant

• Current Assignee: Axonics, Inc.
• Original Assignee: Axonics Modulation Technologies, Inc.
• Inventors: Lee, Henry, Hwu, Alexander
• Granted Patent: US 10,478,619 B2
• Time in Patent Office: Days
• CPC Class Codes: A61N 1/0558 Anchoring or fixation means therefor
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control
• CPC Class Codes: A61N 1/36062 Spinal stimulation
• CPC Class Codes: B23K 2103/14 Titanium or alloys thereof
• CPC Class Codes: B23K 2103/18 Dissimilar materials
• CPC Class Codes: B23K 2103/26 Alloys of Nickel and Cobalt and Chromium
• CPC Class Codes: B23K 26/242 Fillet welding, i.e. involving a weld of substantially triangular cross section joining two parts
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: B29C 45/14065 Positioning or centering articles in the mould
• CPC Class Codes: B29C 45/14598 Coating tubular articles
• CPC Class Codes: B29C 45/14778 the article consisting of a material with particular properties, e.g. porous, brittle
• CPC Class Codes: B29L 2031/753 Medical equipment; Accessories therefor bloodbags, medical bags B29L2031/7148; artificial eyes B29L2011/0008

Abstract

Anchoring devices and methods for affixing an implanted lead of a neurostimulation system at a target location in a patient are provided herein. Such anchoring devices includes a helical body having a plurality of tines extending laterally outward from the lead when deployed that engage tissue to inhibit axial movement of the implanted lead. The plurality of tines are biased towards the laterally extended deployed configuration and fold inward towards the lead to a delivery configuration to facilitate delivery of the lead through a sheath. The tines may be angled in a proximal direction or in both proximal and distal directions and may include various features to assist in visualization and delivery of the lead. The anchor may be formed according to various methods, including laser cutting of a tubular section along with heat or reflow to set the material with the anchor in the deployed configuration and injection molding.

Claims

1-29. -29. (canceled)

30. An anchor for anchoring an implanted neurostimulation lead at a target tissue location in a body of a patient, the anchor comprising:

a helical body extending helically along a longitudinal axis thereof; and

a plurality of tines extending from the helical body, wherein each of the plurality of tines is biased toward a deployed configuration and resiliently deflectable for a delivery configuration,

wherein in the deployed configuration, the plurality of tines extend laterally away from longitudinal axis of the helical body, and in the delivery configuration, the plurality of tines are folded inward toward the longitudinal axis of the helical body to facilitate delivery of the neurostimulation lead during implantation.

31. The anchor of claim 30, wherein the anchor is configured such that when attached to a lead body in the delivery configuration, each of the plurality of tines is folded against the lead body.

32. The anchor of claim 30, wherein the anchor is dimensioned such that, when attached to a lead body and in the delivery configuration, the anchor has a cross sectional profile sufficiently small to facilitate delivery through a 5 French sheath.

33. The anchor of claim 30, wherein the helical body and the plurality of tines are integrally formed of a common material.

34. The anchor of claim 30, wherein the anchor is formed of a material with sufficient stiffness so that, when attached to an implanted lead and in the deployed configuration, engagement of tissue with the plurality of tines inhibits axial movement of the lead when implanted in a tissue of the patient at the target location.

35. The anchor of claim 30, wherein the anchor is molded from a polyurethane based material having a shore hardness in a range between 50A and 80D.

36. A method of forming an anchor for anchoring an implanted neurostimulation lead at a target tissue location in a body of a patient, the method comprising:

laser cutting a helical pattern into a tubular section of material, the pattern corresponding to an neurostimulation lead anchor with a helical body having a plurality of tines in a constrained configuration;

supporting the tines of the tubular section in an outwardly protruding position corresponding to a deployed configuration of the anchor; and

heat setting the tubular section while the tines are supported thereby setting the material while the anchor is in the deployed configuration.

37. The method of claim 36, wherein the material is a shape-memory metal alloy such that the metal alloy resiliently returns to the deployed configuration upon heating in the body after implantation.

38. The method of claim 36, wherein the material is a polymer-based material that is set by reflow and that remains sufficiently flexible when set so that the plurality of tines can fold inward against a lead when constrained within a sheath to facilitate implantation of the anchor when affixed on the lead.

39. The method of claim 36 further comprising:

affixing the anchor to an anchoring portion of a neurostimulation lead by wrapping the helical body about an anchoring portion of the lead.

40. A method of forming an anchor for anchoring an implanted neurostimulation lead at a target tissue location in a body of a patient, the method comprising:

assembling a multi-piece mold defining an outer surface of an anchor comprising a helical body with a plurality of outwardly extending tines with a central core pin defining a central lumen of the helical body;

injecting a flowable material into the assembled mold and allowing the material to at least partly set; and

removing the mold to release the anchor.

41. The method of claim 40, further comprising:

adding a radiopaque ribbon within the mold during assembly and/or adding a radiopaque material to the flowable material before injecting into the assembled mold.

42. The method of claim 40, wherein removing the multi-piece mold comprises withdrawing outer pieces of the multi-piece mold along one or more axes along which the tines extend.

43. The method of claim 40, further comprising:

affixing the anchor to an anchoring portion of a neurostimulation lead by wrapping the helical body about an anchoring portion of a lead.

44. A method of anchoring an implanted neurostimulation lead of a neurostimulation system in a patient, the method comprising:

providing a neurostimulation lead having one or more neurostimulation electrodes and an anchor proximal the one or more electrodes, wherein the anchor includes a helical body wrapped along a length of the lead and a plurality of tines attached to the helical body folded inward against a lead body, the helical body constrained by a sheath;

advancing the lead through a tissue of a patient to a target location while the plurality of tines are folded inward against the lead body constrained by the sheath;

resiliently deploying the one or more tines to a deployed configuration extended laterally outward from the helical body by withdrawing the sheath; and

anchoring the neurostimulation lead at the target location by engaging the plurality of tines in the deployed configuration against adjacent tissues thereby inhibiting axial movement of the implanted lead.

45. The method of claim 44 wherein the target location comprises a sacral nerve for a neurostimulation treatment of OAB such that advancing the lead through the tissue comprises advancing the lead through an S3 foramen until the one or more neurostimulation electrodes are positioned at the sacral nerve.

46. The method of claim 45, wherein anchoring the neurostimulation lead by engaging the plurality of times against adjacent tissues comprises engaging tissues within and/or adjacent the S3 foramen.