FLEXIBLE SELF-EXPANDABLE STENT AND METHODS FOR MAKING THE STENT

摘要

A flexible self-expandable stent comprises a hollow cylindrical inside and outside stent bodies; and a hollow rubber tube closely fitted between the inside and outside stent bodies and having a length similar to a length of each of the inside and outside stent bodies. Overlapped ends of the rubber tube and the inside and outside stent bodies are integrated into a single structure. A flexible self-expandable stent comprises a hollow cylindrical inside and outside stent bodies; and a hollow rubber tube closely fitted between the inside and outside stent bodies and having a length similar to a length of each of the inside and outside stent bodies. Overlapped ends of the rubber tube and the inside and outside stent bodies are integrated into a single structure. The stent bodies are fabricated by knitting first and second super-elastic shape memory alloy wires (10, 11) to make a net-like structure (50) of each of the stent bodies. The first wire, which is zigzagged with a diagonal length P in a longitudinal direction of each stent body, is interlocked with the second wire, which is zigzagged with a diagonal length 2P in the longitudinal direction, at different positions to form interlocked points (60) capable of allowing each stent body to contract and expand in the longitudinal direction. Intersecting points (70) are formed by a repeated intersection of the first and second wires at several positions between the interlocked points to allow each stent body to apply a force against the longitudinal contraction. Diamond-shaped meshes (20) are defined by the interlocked points and the intersecting points. The first and second wires are interlocked with each other to be prevented from being separated from each other while allowing each stent body to contract and expand. An independent claim is also included for a method of producing a flexible self-expandable stent comprising fabricating hollow cylindrical inside and outside stent bodies; fitting a hollow rubber tube closely over the inside stent body and having a length similar to a length of each stent body; fitting the outside stent body closely over the hollow rubber tube; and integrating each of the overlapped ends of the rubber tube and the inside and outside stent bodies into a single structure.