Tissue cutting systems and methods
A probe for resecting and coagulating tissue comprises an outer sleeve having a tissue cutting window and an inner sleeve having a tissue cutting distal end. And RF cutting region is formed at the distal end of the inner member and an RF coagulation region is formed on an exterior surface of the inner member immediately proximal to the cutting surface. A single power supply providing a single RF energy mode can be connected to both RF applicator regions to simultaneously cut and coagulate tissue.
1. A tissue resecting device, comprising:
a handle;
an elongate shaft extending from the handle, the elongate shaft including an outer sleeve and a reciprocating inner resecting sleeve disposed in the outer sleeve, wherein such reciprocation of the inner resecting sleeve moves a distal end of the inner resecting sleeve across a tissue-receiving window of the outer sleeve between window-open and window-closed positions;
a motor drive in the handle;
an actuator in the handle coupled between the motor drive and the inner resecting sleeve to convert rotational motion from the motor drive to linear reciprocation motion of the inner resecting sleeve relative to the outer sleeve for reciprocating the inner resecting sleeve; and
a drive shaft coupled to the actuator;
wherein the actuator converts rotational motion from the motor drive to linear reciprocation motion of the drive shaft such that the drive shaft translates axially relative to the handle;
wherein linear reciprocation motion of the drive shaft is transferred to the inner resecting sleeve via a coupling arm spaced apart from the actuator;
wherein the inner resecting sleeve extends proximal of the actuator and reciprocates relative thereto.
2. The tissue resecting device of claim 1 , wherein the inner resecting sleeve is positioned parallel to and laterally offset from a central longitudinal axis of the drive shaft.
3. The tissue resecting device of claim 2 , wherein the drive shaft is positioned coaxially with the actuator.
4. The tissue resecting device of claim 1 , further comprising a heat exchanger disposed within the handle.
5. The tissue resecting device of claim 4 , wherein the inner resecting sleeve extends proximally within the handle to the heat exchanger.
6. The tissue resecting device of claim 5 , wherein the heat exchanger is configured to use fluid extracted through the inner resecting sleeve to cool the motor drive.
7. The tissue resecting device of claim 5 , wherein the inner resecting sleeve extends through the heat exchanger.
8. The tissue resecting device of claim 1 , wherein a full reciprocation stroke includes an extending stroke in which the inner resecting sleeve moves from the window-open position to the window-closed position and a retracting stroke in which the inner resecting sleeve moves from the window-open position to the window-closed position.
9. The tissue resecting device of claim 8 , wherein the actuator is configured to vary a reciprocation speed of the inner resecting sleeve within one full reciprocation stroke of the inner resecting sleeve independent of changing rotational speed of the motor drive.
10. The tissue resecting device of claim 9 , wherein the inner resecting sleeve has a faster speed during the retracting stroke and a slower speed during the extending stroke.
11. The tissue resecting device of claim 8 , wherein the inner resecting sleeve has a dwell time in a fully extended stroke position to thereby allow negative and/or positive pressures to move tissue through the inner resecting sleeve.
12. The tissue resecting device of claim 11 , wherein the dwell time is at least 0.1 second.
13. The tissue resecting device of claim 1 , further comprising a controller for controlling reciprocation of the inner resecting sleeve.
14. The tissue resecting device of claim 13 , wherein the controller is configured for locking the inner resecting sleeve in a partially extended position between the window-open position and the window-closed position.
15. The tissue resecting device of claim 13 , wherein the controller is configured for locking the inner resecting sleeve in the window-open position.
16. The tissue resecting device of claim 13 , wherein the controller is configured for locking the inner resecting sleeve in the window-closed position.
17. The tissue resecting device of claim 13 , wherein a distal end of the inner resecting sleeve includes an RF electrode having a first polarity and the outer sleeve serves as a return electrode having an opposite, second polarity.
18. The tissue resecting device of claim 17 , wherein the RF electrode is configured to generate plasma for resecting tissue.
19. A tissue resecting device, comprising:
a handle;
an elongate shaft extending from the handle, the elongate shaft including an outer sleeve and a reciprocating inner resecting sleeve slidably disposed in the outer sleeve, wherein reciprocation of the inner resecting sleeve axially translates a distal end of the inner resecting sleeve across a tissue-receiving window of the outer sleeve between a window-open position and a window-closed position;
a motor drive in the handle;
an actuator in the handle coupled between the motor drive and the inner resecting sleeve to convert rotational motion from the motor drive to linear reciprocation motion of the inner resecting sleeve relative to the outer sleeve for reciprocating the inner resecting sleeve; and
a drive shaft coupled to the actuator;
wherein the actuator converts rotational motion from the motor drive to linear reciprocation motion of the drive shaft such that the drive shaft translates axially relative to the handle;
wherein linear reciprocation motion of the drive shaft is transferred to the inner resecting sleeve via a coupling arm spaced apart from the actuator;
wherein the actuator includes an arcuate slot configured to vary a reciprocation speed of the inner resecting sleeve within one full reciprocation stroke of the inner resecting sleeve;
wherein the inner resecting sleeve extends proximal of the actuator and reciprocates relative thereto.