Patent ID: 7993410

Claim:
An esophageal stent, comprising: a stent body having a hollow cylindrical mesh structure formed from interweaved superelastic shape-memory alloy wires; a reverse flow prevention tube, having a substantially cylindrical tubular shape, being coupled to a lower end of the stent body, the reverse flow prevention tube comprising an inside membrane and an outside membrane adhered to each other for forming a flexible twofold structure; and at least one core being longitudinally disposed between the inside and outside membranes, said core extending only a partial distance from an upper end toward a lower end of the reverse flow prevention tube thereby maintaining the substantially cylindrical tubular shape of the reverse flow prevention tube over said partial distance and maintaining a flexible state within a remainder of the reverse flow prevention tube between a lower end of the at least one core and the lower end of the reverse flow prevention tube where the at least one core is not present.