RADIOPAQUE COMPOSITIONS, STENTS AND METHODS OF PREPARATION

• US 20080300673A1
• Filed: 04/02/2008
• Published: 12/04/2008
• Est. Priority Date: 04/16/2007
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Clerc, Claude, Headley, F. Anthony JR., Whitcher, Forrest, Gidwani, Suresh
• Granted Patent: US 8,409,270 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• 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 2/885 comprising a coil including a plurality of spiral or helical sections with alternate directions around a central axis
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

The invention relates to an implantable radiopaque stent adapted to be disposed in a body lumen. In one aspect of the invention, a plurality of elongate filaments including one or more radiopaque filaments are arranged to form a hollow tubular structure having a tubular wall that defines an inner surface and an outer surface and opposing first open end and second open end. One of the open ends of the stent is formed by an intersection of adjacent filament ends. A radiopaque compound is applied to the intersection, the radiopaque compound comprising radiopaque material and polymeric material. The radiopaque compound and radiopaque filament provide improved external imaging of the tubular structure on imaging equipment.

Claims

1. An implantable radiopaque stent comprising:

a plurality of elongate filaments including at least one radiopaque filament, the plurality of filaments arranged to form a hollow tubular structure having a tubular wall that defines an inner surface and an outer surface and opposing first open end and second open end, at least one of the open ends formed by an intersection of adjacent filament ends and application of a radiopaque compound to the intersection, the radiopaque compound comprising radiopaque material and polymeric material, wherein the radiopaque compound and the radiopaque filament improve external imaging of the tubular structure on imaging equipment.

2. The implantable radiopaque stent of claim 1, wherein the at least one radiopaque filament extends outward from the outer surface.

3. The implantable radiopaque stent of claim 1, wherein the at least one radiopaque filament has a diameter greater than the diameter of each of the plurality of filaments.

4. The implantable radiopaque stent of claim 2, comprising a plurality of elongate radiopaque filaments.

5. The implantable radiopaque stent of claim 4, wherein the plurality of radiopaque filaments are arranged in a helix configuration about a centerline of the tubular structure with a common axis.

6. The implantable radiopaque stent of claim 1, wherein the filaments are braided to form the tubular structure.

7. The implantable radiopaque stent of claim 1, wherein at least one of the open ends is trimmed at the intersection.

8. The implantable radiopaque stent of claim 1, wherein the radiopaque compound applied to the intersection is bulb shaped.

9. The implantable radiopaque stent of claim 1, wherein the radiopaque compound is applied from an automated dispenser.

10. The implantable radiopaque stent of claim 1, wherein the radiopaque compound comprises silicone.

11. The implantable radiopaque stent of claim 1, wherein the radiopaque compound comprises a radiopaque powder or paste.

12. The implantable radiopaque stent of claim 1, wherein the radiopaque compound comprises xylene.

13. The implantable radiopaque stent of claim 1, wherein the radiopaque compound comprises at least twenty-five percent of the radiopaque material.

14. The implantable radiopaque stent of claim 1, wherein the imaging equipment is at least one of fluoroscope and x-ray equipment.

15. The implantable radiopaque stent of claim 1, wherein the radiopaque material is selected from the group consisting of gold, barium sulfate, ferritic particles, platinum, platinum-tungsten, palladium, platinum-iridium, rhodium, tantalum and combinations thereof.

16. The implantable radiopaque stent of claim 1, wherein the polymeric material is selected from the group consisting of polyester, polypropylene, polyethylene, polyurethane, polynaphthalene, polytetrafluoroethylene, expanded polytetrafluoroethylene, silicone, and combinations thereof.

17. The implantable radiopaque stent of claim 1, wherein the at least one radiopaque filament comprises a bioabsorbable material and a radiopaque material.

18. The implantable radiopaque stent of claim 17, wherein the bioabsorbable material is adapted to degrade in vivo.

19. The implantable radiopaque stent of claim 17, wherein the bioabsorbable material is selected from the group consisting of poly-L-lactide, poly-D-lactide, polyglycolide, polydioxanone, polycaprolactone, polygluconate, polylactic acid-polyethylene oxide copolymers, modified cellulose, collagen, poly(hydroxybutyrate), polyanhydride, polyphosphoester, poly(amino acids), poly (alpha-hydroxy acid) and combinations thereof.

20. The implantable radiopaque stent of claim 1, wherein the at least one radiopaque filament comprises a polymeric material and a radiopaque material.

21. The implantable radiopaque stent of claim 1, wherein the tubular structure is covered with a polymeric material.

22. The implantable radiopaque stent of claim 21, wherein the polymeric material includes radiopaque particles.

23. The implantable radiopaque stent of claim 1, wherein the tubular structure is treated with pharmaceuticals selected from the group consisting of anti-thrombogenic agents, anti-proliferative agents, anti-inflammatory agents, antineoplastic/antiproliferative/anti-miotic agents, anesthetic agents, anti-coagulants, vascular cell growth promotors, vascular cell growth inhibitors, cholesterol-lowering agents;

vasodilating agents; and

agents which interfere with endogenous vascoactive mechanisms.

24. A method for making an implantable radiopaque stent comprising:

arranging a plurality of elongated filaments comprising at least one radiopaque filament for permanent attachment to a hollow tubular structure in a linear direction traverse to a longitudinal length of the tubular structure, the tubular structure providing a tubular wall defining an interior surface and an exterior surface and having opposed open first and second ends; and

applying a radiopaque compound to an intersection of adjacent filament ends located at one of the opposed open ends, the radiopaque compound comprising radiopaque material and polymeric material, wherein the radiopaque compound and the radiopaque filament improve external imaging of the tubular structure on imaging equipment.

25. The method of claim 24, comprising arranging the plurality of filaments comprises extending the at least one radiopaque filament outward from the outer surface.

26. The method of claim 24, comprising forming the at least one radiopaque filament with a diameter greater than the diameter of each of the plurality of filaments.

27. The method of claim 26, comprising arranging a plurality of elongate radiopaque filaments.

28. The method of claim 27, comprising arranging the plurality of radiopaque filaments in a helix configuration about a centerline of the tubular structure with a common axis.

29. The method of claim 24, comprising forming the tubular structure by braiding the filaments.

30. The method of claim 24, comprising trimming at least one of the open ends at the intersection.

31. The method of claim 24, comprising applying the radiopaque compound to the intersection in a bulb shape.

32. The method of claim 24, comprising dispensing the radiopaque compound from an automated dispenser.

33. The method of claim 24, comprising compounding silicon into the radiopaque compound.

34. The method of claim 24, comprising forming the radiopaque compound from at least one of a radiopaque powder and paste.

35. The method of claim 24, comprising adding xylene to the radiopaque compound.

36. The method of claim 24, wherein at least twenty-five percent of the radiopaque compound comprises radiopaque material.

37. The method of claim 24, wherein the imaging equipment is at least one of fluoroscope and x-ray equipment.

38. The method of claim 24, comprising selecting the radiopaque material from the group consisting of gold, barium sulfate, ferritic particles, platinum, platinum-tungsten, palladium, platinum-iridium, rhodium, tantalum and combinations thereof.

39. The method of claim 24, comprising selecting the polymeric material from the group consisting of polyester, polypropylene, polyethylene, polyurethane, polynaphthalene, polytetrafluoroethylene, expanded polytetrafluoroethylene, silicone, and combinations thereof.

40. The method of claim 24, comprising forming the at least one radiopaque filament from a bioabsorbable material and a radiopaque material.

41. The method of claim 40, comprising adapting the bioabsorbable material to degrade in vivo.

42. The method of claim 40, comprising selecting the bioabsorbable material from the group consisting of poly-L-lactide, poly-D-lactide, polyglycolide, polydioxanone, polycaprolactone, polygluconate, polylactic acid-polyethylene oxide copolymers, modified cellulose, collagen, poly(hydroxybutyrate), polyanhydride, polyphosphoester, poly(amino acids), poly (alpha-hydroxy acid) and combinations thereof.

43. The method of claim 24, comprising forming the at least one radiopaque filament from a polymeric material and a radiopaque material.

44. The method of claim 24, comprising covering the tubular structure with a polymeric material.

45. The method of claim 44, comprising forming the polymeric material from radiopaque particles.

46. The method of claim 24 comprising treating the tubular structure with pharmaceuticals selected from the group consisting of anti-thrombogenic agents, anti-proliferative agents, anti-inflammatory agents, antineoplastic/antiproliferative/anti-miotic agents, anesthetic agents, anti-coagulants, vascular cell growth promoters, vascular cell growth inhibitors, cholesterol-lowering agents;

vasodilating agents, agents which interfere with endogenous vascoactive mechanisms, and combinations thereof.