Variable Stiffness Guidewire Systems

A variable-stiffness guidewire assembly comprising:

• an elongated flexible guidewire, the guidewire having a body having a proximal end and a distal end, the guidewire including a tensioning wire having a first end and a second end, the first end coupled to the distal end of the body, the guidewire including a tension head coupled to the second end of the tensioning wire, wherein the tensioning wire is longitudinally movable with respect to the body to adjust a stiffness of the guidewire, the guidewire including a collar located at the proximal end of the guidewire, the collar including at least one protrusion within which applies a frictional force onto the tensioning wire to maintain the tension head at a desired distance with respect to the guidewire;
• and
• a tool configured to receive and secure the tensioning head and the collar within, the tool including a main body and an actuator in longitudinal communication with the main body, wherein the actuator is longitudinally moveable with respect to the main body to move the tensioning head a desired distance with respect to the collar to achieve a desired stiffness in the guidewire.