Expandable and contractible guidewire

1 . A guidewire for a stent assembly, the guidewire comprising an outwardly expandable and inwardly contractible deformable portion.

2 . The guidewire according to claim 1 , wherein said deformable portion is formed on an outer slender tube, and a pull wire is disposed through said outer slender tube and connected to said deformable portion, wherein shifting said pull wire with respect to said outer slender tube moves said deformable portion between a collapsed orientation and an expanded orientation.

3 . The guidewire according to claim 2 , wherein proximally shifting said pull wire with respect to said outer slender tube moves said deformable portion to the expanded orientation, and distally shifting said pull wire with respect to said outer slender tube moves said deformable portion to the collapsed orientation.

4 . The guidewire according to claim 2 , wherein said pull wire is connected to a distal end of said deformable portion.

5 . The guidewire according to claim 1 , wherein said deformable portion comprises a plurality of support surfaces separated by cutouts.

6 . The guidewire according to claim 2 , wherein said support surfaces are contiguous and flush with the rest of the outer slender tube.

7 . The guidewire according to claim 1 , wherein said guidewire includes an elastic endpiece.

8 . A method comprising:

providing a guidewire that includes an outwardly expandable and inwardly contractible deformable portion;

manipulating said guidewire through vasculature to an occlusion; and

expanding said guidewire so as to break said occlusion.

9 . The method according to claim 8 , further comprising expanding said guidewire to anchor it in vasculature.