Metal structure compatible with mri imaging, and method of manufacturing such a structure

• US 20060173529A1
• Filed: 03/14/2003
• Published: 08/03/2006
• Est. Priority Date: 03/14/2002
• Status: Active Grant

• Current Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Original Assignee: Angiomed BMBH & Company Medizintechnik KG
• Inventors: Blank, Thiemo Arnim
• Granted Patent: US 7,789,906 B2
• Time in Patent Office: Days
• US Class Current: 623/1.160
• 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 2/91 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 2002/828 Means for connecting a plurality of stents allowing flexibility of the whole structure
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• 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 2002/91591 Locking connectors, e.g. using male-female connections
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0039 differing in diameter

Abstract

The present invention relates to tubular radially expansible metal structures, having an abluminal wall, a luminal wall and a radial wall thickness therebetween with struts defining through-apertures in the wall, the structure further defining a plurality of expansible rings arranged adjacent one another along the longitudinal axis of the structure, each of the rings defining at least one bridge strut, and adjacent rings being linked by a bridge extending between adjacent bridge struts on adjacent rings. The bridges, a plurality of which are distributed throughout the length of the tubular structure and are configured and arranged to divide the tubular structure into axially spaced and electrically insulated sections, advantageously exhibit reduced electrical conductivity throughout their wall thickness. The present invention relates furthermore to a method of manufacturing such a tubular structure, as well as a method of visualizing a bodily lumen supported by such a tubular structure deployed therein.

Claims

1-24. -24. (canceled)

25. A tubular radially expansible metal structure, comprising:

a wall comprising an abluminal major wall surface, a luminal major wall surface and a radial wall thickness therebetween, the wall having struts defining through-apertures therein; and

a plurality of expansible rings arranged adjacent one another along a longitudinal axis of the structure, each of the rings defining at least one bridge strut and adjacent rings being linked by at least one bridge formed by cooperation between adjacent bridge struts on adjacent rings;

wherein said at least one bridge exhibits reduced electrical conductivity throughout the wall thickness, and wherein there are a plurality of said bridges distributed throughout the length of the tubular structure and configured and arranged to divide the tubular structure into axially spaced and electrically insulated sections.

26. The structure according to claim 25, wherein said bridge comprises inter-engaged joint portions.

27. The structure according to claim 25, wherein said bridge comprises complementary mating portions.

28. The structure according to claim 27, wherein the mating portions are male-female form-fitting portions.

29. The structure according to claim 28, wherein the form-fitting portions have a frusto-conical shape.

30. The structure according to claim 28, wherein the male form-fitting portion comprises a mating head portion having an arcuate end surface, and the female form-fitting portion comprises a mating arcuate end portion with a rebated internal abutment surface to receive the arcuate head portion.

31. The structure according to claim 27, wherein at least one of the mating portions carries a biocompatible adhesive for enhancing the rigidity of said bridge.

32. The structure according to claim 27, wherein a portion of reduced electrical conductivity comprises a conductivity reducing layer on an abutment surface of at least one of the complementary mating portions.

33. The structure according to claim 25, wherein a portion of reduced electrical conductivity comprises a portion in which the chemical composition of said metal structure is modified.

34. The structure according to claim 25, wherein a portion of reduced electrical conductivity comprises an oxide layer.

35. The structure according to claim 25, wherein said bridges comprise a sleeve connected to adjacent bridge struts, and wherein said bridge struts are spaced apart within said sleeve.

36. The structure according to claim 25, wherein the longitudinal axis of said bridge is not parallel to the longitudinal axis of the structure.

37. The structure according to claim 25, wherein said bridge has the shape of a meander.

38. The structure according to claim 25, wherein the rings have the shape of a meander.

39. The structure according to claim 38, wherein the number of bridges connecting one ring with an adjacent ring is less than the number of meanders in one ring.

40. The structure according to claim 25, wherein the shape of the bridge resembles that of an “

S”

.

41. The structure according to claim 25, wherein the structure is made of a nickel titanium shape-memory alloy.

42. The structure according to claim 25, wherein the structure is made of stainless steel.

43. The structure according to claim 25, wherein the structure is a medical stent.

44. A method of manufacturing a tubular radially expansible metal structure hang an abluminal major wall surface, a luminal major wall surface and a radial wall thickness therebetween, comprising the steps of:

forming a plurality of expansible rings so that the rings are arranged adjacent one another along the longitudinal axis of the structure and each of the rings define at least one bridge strut;

forming bridges between adjacent rings by approximating respective bridge struts of adjacent rings; and

furnishing said bridges between each ring and its adjacent ring with reduced electrical conductivity throughout the wall thickness, such that there are a plurality of bridges distributed throughout the length of the tubular structure, arranged and configured to divide the tubular structure into axially spaced and electrically insulated sections.

45. The method according to claim 44, wherein the step of forming the expansible rings further comprises the steps of:

providing a tubular workpiece;

mounting the tubular workpiece on a support; and

laser-cutting the workpiece to form meanders in the rings arranged longitudinally adjacent one another, each having a first end and a second end, and at least one complementary mating portion arranged on said first end of each of said rings to mate with a complementary mating portion on the second end of an adjacent ring.

46. The method according to claim 45, wherein the tubular workpiece has a longitudinal axis of rotation and the direction of the laser cutting beam when cutting the workpiece intersects said longitudinal axis.

47. The method according to claim 45, wherein the direction of the laser cutting beam for making the bridge struts departs from a direction which intersects said longitudinal axis.

48. The method according to claim 44, wherein the step of linking each of the rings with an adjacent ring by at least one bridge includes the step of oxidizing abutment surfaces on said bridge struts, whereby each bridge includes a conductivity reducing layer which constitutes a portion of reduced conductivity.

49. The method according to claim 44, wherein the step of linking each of the rings with an adjacent ring by at least one bridge includes the steps of:

providing an insulating sleeve; and

mounting said sleeve to adjacent bridge struts on adjacent rings, such that the bridge struts are spaced apart within said sleeve.