Stent for placement in a body tube

• US 5,674,277 A
• Filed: 11/22/1995
• Issued: 10/07/1997
• Est. Priority Date: 12/23/1994
• Status: Expired due to Term

• Current Assignee: Merit Medical Systems, Inc.
• Original Assignee: Willy Rüsch AG
• Inventors: Freitag, Lutz
• Primary Examiner(s): Zuttarelli, P.
• Application Number:
  US08/561,811
• Time in Patent Office: 685 Days
• Field of Search: 623/1-2, 623/11-12, 606/77-78, 606/194
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/07 Stent-grafts
• 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 2/89 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 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61L 31/02 Inorganic materials
• CPC Class Codes: A61L 31/14 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials

Abstract

A stent for placement in a body tube includes a flexible support structure composed of an elastomer which is hard in a temperature range lower than 25° C. and soft in a temperature range greater 35° C. The flexible support structure may be embedded in a hollow cylindrical casing of an elastic synthetic material which has a limited elasticity at least at body temperature, wherein the casing is composed of an elastomer which is hard in a temperature range lower than 25° C. and soft in a temperature range greater than 35° C. The casing in which the flexible support structure is embedded may also be of a memory elastomer, particularly on the basis of polyurethane.

Claims

1. A stent for placement in a body tube, the stent comprising a flexible support structure, wherein the support structure is of an elastomer which has a high stiffness in a temperature range lower than 25°

C. and is soft so as to be flexible such that the structure can be easily guided around curvatures of the body tube in a temperature range higher than 35°

C., wherein the support structure has meshes, the meshes having a size selected such that tissue capable of functioning can grow through the meshes.

2. The stent according to claim 1, wherein the support structure comprises at least one thread, the at least one thread being braided for stabilizing the support structure.

3. The stent according to claim 1, wherein the support structure comprises threads, the threads being braided for stabilizing the support structure.

4. The stent according to claim 3, further comprising at least one additional thread of a memory metal.

5. The stent according to claim 4, wherein the thread is of a nickel/titanium alloy.