Catheter

1. A method for using a catheter, the method comprising:

providing a catheter including:

a sheath configured to be inserted into a lumen;

a drive shaft configured to be removably inserted into the sheath and to deliver a mechanical drive force;

an imaging information acquiring unit which is fixed to a distal end of the drive shaft and acquires image information;

a hub configured to move while holding the drive shaft and thereby move the drive shaft in an axial direction of the sheath;

an outer tube which is provided on a proximal end side of the sheath and includes a first connector;

a second connector, the second connector being configured to be connected to and disconnected from the first connector; and

an inner tube provided on a distal end side of the hub and configured to move with respect to the outer tube in the outer tube along with the movement of the hub;

disconnecting the second connector from the first connector;

moving the inner tube and the drive shaft to the proximal end side with respect to the outer tube along with the hub, the inner tube engaging the second connector and thereby preventing separation of the inner tube from the outer tube;

while the inner tube is engaged by the second connector, moving the second connector to the proximal end side; and

thereafter, pulling the drive shaft out from the sheath and the outer tube.

2. The method according to claim 1 , wherein moving the inner tube to the proximal end side includes withdrawing the inner tube to a maximum extent from the outer tube.

3. The method according to claim 1 , wherein the inner tube includes a latch section with an enlarged outer diameter, the inner tube engaging the second connector including the latch section engaging the second connector.

4. The method according to claim 1 , wherein the second connector includes a passing port, and wherein said moving the inner tube and the drive shaft to the proximal end side includes sliding the inner tube through the passing port of the second connector.

5. The method according to claim 1 , wherein disconnecting the second connector from the first connector includes rotating the second connector relative to the first connector.

6. The method according to claim 1 , wherein pulling the drive shaft out from the sheath and the outer tube includes pulling the imaging information acquiring unit out from the sheath and the outer tube.

7. The method according to claim 6 , further comprising inserting a separate wire into a lumen of the sheath and advancing the separate wire to a distal end of the sheath.

8. A method for using a catheter, the method comprising:

providing a catheter including:

a sheath configured to be inserted into a lumen;

a drive shaft configured to be removably inserted into the sheath and to deliver a mechanical drive force;

an imaging information acquiring unit fixed to a distal end of the drive shaft;

a hub configured to move while holding the drive shaft and thereby move the drive shaft in an axial direction of the sheath;

an outer tube which is provided on a proximal end side of the sheath and includes a first connector;

a second connector, the second connector being configured to be connected to and disconnected from the first connector; and

an inner tube provided on a distal end side of the hub and configured to move with respect to the outer tube in the outer tube along with the movement of the hub;

indwelling an introducer sheath in a lumen;

inserting a guiding catheter into the lumen through the introducer sheath;

inserting the catheter into the lumen through the guiding catheter whereby a distal end of the sheath passes through a target lesion;

driving the drive shaft so as to rotate the imaging information acquiring unit, thereby acquiring image information;

disconnecting the second connector from the first connector;

moving the inner tube and the drive shaft to the proximal end side with respect to the outer tube along with the hub, the inner tube engaging the second connector and thereby preventing separation of the inner tube from the outer tube;

while the inner tube is engaged by the second connector, moving the second connector to the proximal end side; and

thereafter, pulling the drive shaft out from the sheath and the outer tube.

9. The method according to claim 8 , wherein moving the inner tube to the proximal end side includes withdrawing the inner tube to a maximum extent from the outer tube.

10. The method according to claim 8 , wherein the inner tube includes a latch section with an enlarged outer diameter, the inner tube engaging the second connector including the latch section engaging the second connector.

11. The method according to claim 8 , wherein the second connector includes a passing port, and wherein said moving the inner tube and the drive shaft to the proximal end side includes sliding the inner tube through the passing port of the second connector.

12. The method according to claim 8 , wherein disconnecting the second connector from the first connector includes rotating the second connector relative to the first connector.

13. The method according to claim 8 , wherein pulling the drive shaft out from the sheath and the outer tube includes pulling the imaging information acquiring unit out from the sheath and the outer tube.

14. The method according to claim 13 , further comprising inserting a separate wire into a lumen of the sheath and advancing the separate wire to a distal end of the sheath.