SELF-EXPANDABLE STENT

摘要

The object of this invention is to provide a self-expandable stent, made of a shape-memory alloy and used for insertion in a narrow or blocked target portion of the contracted gullet having a lesion so as to open the target portion. The stent includes a coated primary unit (10) having a hollow cylindrical body (2) fabricated by knitting a shape-memory alloy wire to make a net structure, with both an enlarged diameter part (5) and a coat layer (7). An uncoated secondary unit (10') surrounds the hollow cylindrical body (2) of the coated primary unit (10). The secondary unit (10') has a hollow cylindrical body (2') fabricated by knitting a superelastic shape-memory alloy wire to make a net structure having diamond-shaped meshes (3'). The stent is prevented from being undesirably removed from a narrow or blocked target portion of the gullet having a lesion.