Adjustable stiffness medical devices
A medical device may include: a shaft configured to be inserted into a body lumen of a subject; a handle at a proximal end of the shaft, the handle including an adjustment mechanism configured to be transitioned from a first configuration, in which the shaft has a first stiffness, to a second configuration, in which the shaft has a second stiffness. The first stiffness may be different from the second stiffness.
1. A medical device including:
a shaft configured to be inserted into a body lumen of a subject;
a handle at a proximal end of the shaft, the handle including a slidable lever and an arm extending radially inward into a cavity defined by a housing of the handle, wherein the slidable lever includes a contact portion for being contacted by a user;
at least one Bowden cable having a Bowden sheath; and
a body configured to exert a distal force on a proximal end of the Bowden sheath, wherein the slidable lever is configured to move the body proximally or distally, and wherein the slidable lever is configured to be transitioned from a first, proximal configuration, in which the shaft has a first stiffness, to a second, distal configuration, in which the shaft has a second stiffness, wherein the first stiffness is different from the second stiffness.
2. The medical device of claim 1 , wherein the shaft includes at least one control mechanism extending therethrough, and wherein the slidable lever is configured to change a force on the at least one control mechanism.
3. The medical device of claim 2 , wherein a first force is exerted on the slidable lever in the first configuration and a second force is exerted on the slidable lever in the second configuration, and wherein the first force is greater than the second force.
4. The medical device of claim 1 , wherein the handle includes a plurality of openings or recesses configured to receive a portion of the slidable lever to fix the slidable lever relative to the handle.
5. The medical device of claim 1 , wherein the arm of the slidable lever is configured to contact a distally-facing surface of the body.
6. The medical device of claim 1 , wherein the slidable lever is pivotally connected to the arm.
7. A medical device including:
a shaft configured to be inserted into a body lumen of a subject; and
a handle at a proximal end of the shaft, the handle including:
at least one Bowden cable having a Bowden sheath;
a body configured to exert a distal force on the Bowden sheath; and
an actuator coupled to a scissor lift, wherein rotation of the actuator in a first direction closes the scissor lift and moves the body proximally, wherein rotation of the actuator in a second direction opens the scissor lift and moves the body distally, and wherein proximal movement and distal movement of the body changes an amount of the distal force on the Bowden sheath.
8. The medical device of claim 7 , wherein the actuator includes a knob and a shaft fixed to the scissor lift, wherein the shaft includes threads configured to interact with the scissor lift.
9. The medical device of claim 8 , wherein the threads of the shaft include a first portion of threads and a second portion of threads, wherein the first portion of threads interact with a first arm of the scissor lift and the second portion of threads interact with a second arm of the scissor lift.
10. The medical device of claim 9 , wherein the first portion of threads faces a first direction, and wherein the second portion of threads faces a second direction.
11. The medical device of claim 7 , wherein the scissor lift is configured to contact a distally-facing surface of the body.
12. The medical device of claim 7 , wherein the scissor lift includes a first arm hinged relative to a second arm, and wherein, upon closing the scissor lift, proximal ends and distal ends of each of the first arm and the second arm are configured to move inwards and towards one another.
13. A medical method, comprising:
inserting a shaft of a medical device into a body lumen of a subject; and
activating an adjustment mechanism on a handle of the medical device in order to cause the shaft of the medical device to increase in flexibility, wherein the adjustment mechanism includes a lever having a contact portion configured for contact by a user, and wherein the lever is configured to pivot.
14. The medical method of claim 13 , wherein activating the adjustment mechanism causes a body to move proximally relative to a housing of the handle.
15. The medical method of claim 13 , further comprising:
de-activating the adjustment mechanism on the handle of the medical device in order to cause the shaft of the medical device to decrease in flexibility; and
locking the lever relative to the handle.
16. The medical method of claim 15 , wherein the medical device further includes a body, and wherein, upon activating the adjustment mechanism of the medical device, the body is moved proximally, and wherein, upon de-activating the adjustment mechanism of the medical device, the body is moved distally.
17. The medical method of claim 13 , wherein the lever includes a cam.
18. The medical method of claim 17 , wherein the cam is positioned between a body and a structure that is fixed relative to the handle.
19. The medical method of claim 18 , wherein the cam is movable via the lever.
20. The medical method of claim 13 , wherein the lever includes an arm, and wherein the arm is configured to be received within a plurality of notches disposed on the handle.