ANNULAR MESH

• US 20100016949A1
• Filed: 08/28/2007
• Published: 01/21/2010
• Est. Priority Date: 08/29/2006
• Status: Active Grant

• Current Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Original Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Inventors: Wack, Thilo
• Granted Patent: US 9,254,207 B2
• Time in Patent Office: Days
• US Class Current: 623/1.150
• CPC Class Codes: A61F 2/04 Hollow or tubular parts of organs, e.g. bladders, tracheae, bronchi or bile ducts A61F2/18, A61F2/20 take precedence; devices, other than stent-grafts, providing patency to, or preventing collapsing of, tubular structures of the body other than stent-grafts, e.g. stents A61F2/82; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91583 by a bridge, whereby at least one of its ends is connected along the length of a strut between two consecutive apices within a band

Abstract

An annular mesh expandable radially from a compact diameter to a radially-expanded deployed disposition in which the mesh is capable of sustaining a radially outwardly directed resistive force even when flexing its longitudinal axis out of a straight line, the mesh being composed of stenting struts, the stenting struts being arranged in a plurality of zig-zag strings around the circumference of the lumen, with occasional connector struts joining adjacent strings to create a closed circumference unit cell between two such connector struts and two adjacent connected strings there being a plurality of such unit cells arranged in sequence around the circumference between said two adjacent strings; and characterised in that there is a non-constant increment of strut length, serving to displace along the longitudinal axis each unit cell relative to the circumferentially next adjacent unit cell.

Claims

1. An annular mesh that defines a lumen that surrounds a longitudinal axis of the mesh, the mesh being expandable radially from a compact diameter pre-deployment disposition to a radially expanded deployed disposition in which the mesh is capable of sustaining a radially outwardly directed resistive force even when flexing in response to externally applied forces that bend its longitudinal axis out of a straight line, the mesh being composed of stenting struts, the stenting struts being arranged in a plurality of zig-zag string around the circumference of the lumen, with occasional connector struts joining adjacent strings of stenting struts thereby to create a closed circumference unit cell between two such connector struts and two adjacent connected strings of stenting struts there being a plurality of such unit cells arranged in sequence around the circumference between said two adjacent string of stenting struts;

and comprising a non-constant increment of strut length, within the portion of each of the two said zig-zag string of stenting struts bounding any one said unit cell said non-constant increment serving to displace along the longitudinal axis each unit cell bounded by said zig-zag string relative to the circumferentially next adjacent unit cell bounded by the same zig-zag string.

2. The mesh according to claim 1, which is a stent for a lumen of the human or animal body.

3. The mesh according to claim 1, wherein the length of the struts of each said zig-zag string portion is constant, except for one strut in each one of the two portions, which is shorter than the other struts of the said portion.

4. The mesh according to claim 1, wherein the length of the struts of each zig-zag string portion is constant, except for two struts in each one of the two portions which are shorter than the other struts of the said portion.

5. The mesh according to 1, wherein the increment of strut length between any two adjacent struts within each one of the two zig-zag string portions of said unit cell is finite and constant, except for an axial offsetting increment that lies between one and only one adjacent pair of struts of the said one string, which offsetting increment is different from said constant increment.

6. The mesh according to claim 1, wherein the increment of strut length between any two adjacent struts within each one of the two zig-zag string portions of each unit cell is finite and constant, except for an axial offsetting increment that lies between two and only two adjacent pairs of struts of the portion, which offsetting increment is different from said constant increment, and not necessarily the same for both of the only two adjacent pairs of struts.

7. The mesh according to claim 1, in which the mesh of struts is compatible with manufacture out of a seamless tube, by slitting the tube, through its wall thickness with a multiplicity of slits.

8. The mesh according to claim 7, wherein most or all of the slits are straight.

9. The mesh according to claim 8, wherein the straight slits are parallel to the long axis of the tube.

10. The mesh according to claim 8, wherein the connector struts are also formable by slitting the tube.

11. The mesh according to claim 10, wherein connector struts are straight.

12. The mesh according to claim 11, wherein the straight connector struts are parallel to the long axis of the tube.

13. The mesh according to claim 1, wherein the zig-zag strings face each other, in the compact pre-deployment disposition peak to peak yet, upon radial expansion to the deployed disposition, these facing peaks of the zig-zag strings move circumferentially away from the facing relationship and into a non-facing (peak-to-valley) relationship thereby enhancing the bending flexibility of the expanded mesh.

14. The mesh according to claim 1, wherein each said string of stenting struts exhibits a plurality of circumferentially spaced apart three leg nodes, where a connector strut merges with the zig-zag string, the portion of the zig-zag string between two such nodes being oriented perpendicular to the longitudinal axis, whereby the nodes correspond to steps where the zig-zag strings advance axially along, the longitudinal axis.

15. The mesh according to claim 14, wherein the closed circumference of each said unit cell including six said nodes.

16. The mesh according to claim 1, wherein the unit cells axially one side of one of the zig-zag strings and the unit cells on the other axial side of the string are alike.

17. The mesh according to claim 1, wherein the unit cells axially one side of one of the zig-zag strings are of one form, and those on the other side of that zig-zag string are of another form.

18. An annular mesh that defines a lumen that surrounds a longitudinal axis of the mesh, the mesh being expandable radially from a compact diameter pre-deployment disposition to a radially expanded deployed disposition in which the mesh is capable of sustaining a radially outwardly directed resistive force even when flexing in response to externally applied forces that bend its longitudinal axis out of a straight line, the mesh being composed of stenting struts, the stenting struts being arranged in a plurality of zig-zag strings around the circumference of the lumen, with occasional connector struts joining adjacent strings of stenting struts thereby to create a closed circumference unit cell between two such connector struts and two adjacent connected strings of stenting struts there being a plurality of such unit cells arranged in sequence around the circumference between said two adjacent strings of stenting struts;

and wherein each zig-zag string of stenting struts advances around the circumference in a pattern, which is neither continuously slanting to the longitudinal axis, as the bishop on a Chessboard, nor continuously perpendicular to the longitudinal axis, as the rook on a chessboard, but both perpendicular and across, as with the knight on a chessboard.