Patent ID: 8043355

Claim:
A double-tube type stent comprising: a hollow cylindrical body having a plurality of rhombic spaces formed by weaving a superelastic shape-memory-alloy wire so as to be crossed; a silicon coating layer coated on the outer surface of the cylindrical body using a silicon solution; and a polytetrafluoroethylene tube fixedly fitted around the cylindrical body, having the silicon coating layer, to form a plurality of gaps, wherein each gap is an empty space enclosed by portions of the silicon coating layer that are formed on the wire, portions of the silicon coating layer that cover the rhombic spaces between the wire, and the polytetrafluoroethylene tube, and wherein the plurality of gaps serve as buffers to inhibit a lesion from a duct into which the stent is inserted from protruding into the rhombic spaces of the hollow cylindrical body.