Medical device and procedure method

A medical device to be inserted into a biological lumen for collecting an object in the biological lumen, the medical device comprising:

• an elongated shaft possessing a distal end portion;
• an expansion portion that includes an elastically deformable body, the elastically deformable body possessing a proximal portion and a distal portion, the elastically deformable body including a plurality of through gaps that pass through the elastically deformable body;
• the proximal portion of the elastically deformable body being interlocked with a proximal side interlock portion;
• the distal end portion of the elongated shaft being fixed in place relative to the elastically deformable body by way of the proximal side interlock portion so that the elongated shaft and the proximal side interlock portion move together as a unit whereby movement of the elongated shaft results in movement of the proximal side interlock portion, the elongated shaft extending away from the elastically deformable body in a proximal direction;
• the expansion portion including, when the expansion portion is in a bent state, a radially outwardly located annular-shaped portion that is bent toward the proximal direction;
• the expansion portion being changeable between the bent state and an extended state, the expansion portion in the bent state including a first portion and a second portion, the second portion being located inside the first portion when the expansion portion is in the bent state, and the second portion moving in the proximal direction with respect to the first portion and being pulled out from the inside of the first portion when the expansion portion changes from the bent state to the extended state;
• and
• the elongated shaft being the only elongated shaft that is fixed in place relative to the elastically deformable body and that also extends away from the elastically deformable body in the proximal direction.

A medical device to be inserted into a biological lumen for collecting an object in the biological lumen, the medical device comprising:

• an elongated shaft possessing a distal end portion;
• an expansion portion that includes an elastically deformable body having a plurality of through gaps that pass through the elastically deformable body, the expansion portion possessing a proximal portion and a distal portion;
• the proximal portion of the expansion portion being interlocked with a proximal side interlock portion, the proximal side interlock portion including an outer tube and an inner tube, the inner tube being positioned inside the outer tube;
• the distal end portion of the elongated shaft being fixed to at least one of the inner tube of the proximal side interlock portion and the outer tube of the proximal side interlock and extending away from the expansion portion in a proximal direction;
• the expansion portion being changeable from an extended state to a bent state by a restoring force of the expansion portion and without application of any forces external to the expansion portion so that as the expansion portion changes form from the extended state to the bent state, the expansion portion expands radially outwardly and an axial distance between the distal portion of the expansion portion and the proximal portion of the expansion portion is reduced;
• the expansion portion including, when the expansion portion is in the bent state, a radially outwardly located annular-shaped portion that is bent toward the proximal direction;
• and
• the expansion portion in the bent state including a first portion and a second portion, the second portion being located inside the first portion when the expansion portion is in the bent state, the expansion portion being changeable from the bent state to the extended state, and the second portion moving in the proximal direction with respect to the first portion and being pulled out from the inside of the first portion when the expansion portion changes from the bent state to the extended state.