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 at a reciprocation speed;
a motor drive in the handle; and
an actuator in the handle coupled between the motor drive and the inner resecting sleeve to convert rotational motion from the motor drive to reciprocation motion of the inner resecting sleeve relative to the outer sleeve for reciprocating the inner resecting sleeve at the reciprocation speed, wherein the actuator is configured to vary the reciprocation speed within one full reciprocation stroke of the inner reciprocating sleeve independent of changing rotational speed of the motor drive;
wherein the actuator includes an actuator body with an arcuate slot therein, wherein rotational motion from the motor drive rotates the actuator body; and
wherein the inner resecting sleeve extends proximal of the actuator body and reciprocates relative thereto.
2. The tissue resecting device of claim 1 , wherein the 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.
3. The tissue resecting device of claim 2 , wherein the inner resecting sleeve has a faster speed during the retracting stroke and a slower speed during the extending stroke.
4. The tissue resecting device of claim 2 , 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.
5. The tissue resecting device of claim 4 , wherein the dwell time is at least 0.1 second.
6. The tissue resecting device of claim 1 , further comprising a controller for controlling reciprocation of the inner resecting sleeve.
7. The tissue resecting device of claim 6 , 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.
8. The tissue resecting device of claim 6 , wherein the controller is configured for locking the inner resecting sleeve in the window-open position.
9. The tissue resecting device of claim 6 , wherein the controller is configured for locking the inner resecting sleeve in the window-closed position.
10. The tissue resecting device of claim 6 , 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.
11. The tissue resecting device of claim 10 , wherein the RF electrode is configured to generate plasma for resecting tissue.