Tissue extraction devices and methods
The tissue cutting device comprises an elongated assembly including both an outer sleeve and an inner sleeve. The outer sleeve has a tissue-receiving window, and the inner sleeve has a distal end which cuts tissue as the inner sleeve is advanced past the window. The tissue is received into a lumen of the inner sleeve, and the inner sleeve lumen is typically enlarged in a proximal direction to reduce the tendency of resected tissue to lodge therein. The tissue displacement member is optionally provided at a distal end of the outer sleeve to further aid in dislodging tissue which becomes captured in a distal end of the inner sleeve of the lumen.
1. A tissue resecting device, comprising:
an outer sleeve having a tissue-receiving window opening into a lumen of the outer sleeve; and
an axially reciprocating inner sleeve disposed within the lumen of the outer sleeve, the inner sleeve having a lumen and a tissue-resecting distal end, the inner sleeve being configured to move longitudinally between an open window position and a closed window position;
wherein the outer sleeve includes a distal tip fixedly attached to a distal end of the outer sleeve and a projecting element extending proximally from the distal tip;
wherein the projecting element is disposed distal of the lumen of the inner sleeve in the open window position and extends into the lumen of the inner sleeve in the closed window position;
wherein the tissue-receiving window is longitudinally asymmetrical.
2. The tissue resecting device of claim 1 , wherein a depth of the tissue-receiving window from an outer surface of the outer sleeve varies along a length of the tissue-receiving window.
3. The tissue resecting device of claim 2 , wherein the depth of the tissue-receiving window increases in a distal direction.
4. The tissue resecting device of claim 1 , wherein the tissue-resecting distal end has a first cross-sectional area less than a second cross-sectional area at a portion of the inner sleeve proximal of the tissue-resecting distal end.
5. The tissue resecting device of claim 4 , wherein the projecting element has a maximum cross-sectional area that extends substantially across the first cross-sectional area.
6. The tissue resecting device of claim 1 , wherein the projecting element has a substantially symmetric shape.
7. The tissue resecting device of claim 1 , wherein the projecting element comprises ribs and channels extending longitudinally.
8. The tissue resecting device of claim 1 , wherein the lumen of the inner sleeve is in fluid communication with a negative pressure source configured to aspirate resected tissue therethrough.
9. The tissue resecting device of claim 1 , wherein an edge of the tissue-receiving window is configured with gripping features.
10. The tissue resecting device of claim 9 , wherein the edge includes teeth or an abrasive surface.
11. A tissue resecting device, comprising:
an outer sleeve having a longitudinally asymmetrical tissue-receiving window opening into a lumen of the outer sleeve; and
an inner sleeve slidably disposed within the lumen of the outer sleeve and having a tissue-resecting distal end, wherein a lumen of the inner sleeve is in fluid communication with a negative pressure source configured to aspirate resected tissue through the lumen of the inner sleeve;
wherein the outer sleeve includes a distal tip fixedly attached to a distal end of the outer sleeve and a tissue displacement feature extending proximally from the distal tip within the lumen of the outer sleeve;
wherein the tissue displacement feature extends proximal of a distal end of the tissue-receiving window;
wherein the inner sleeve moves longitudinally relative to the tissue displacement feature.
12. The tissue resecting device of claim 11 , wherein the inner sleeve has a first cross-sectional area extending from a proximal end of the inner sleeve to a distal region of the inner sleeve.
13. The tissue resecting device of claim 12 , wherein the tissue-resecting distal end defines a second cross-sectional area smaller than the first cross-sectional area.
14. The tissue resecting device of claim 13 , wherein a length of the tissue displacement feature is at least as long as an axial length of the second cross-sectional area defined by the tissue-resecting distal end.
15. The tissue resecting device of claim 11 , wherein a distal portion of the tissue-receiving window defines a larger opening into the lumen of the outer sleeve than a proximal portion of the tissue-receiving window.
16. A tissue resecting device, comprising:
an outer sleeve having a tissue-receiving window opening into a lumen of the outer sleeve; and
an inner sleeve slidably disposed within the lumen of the outer sleeve and configured to shift longitudinally between an open window position and a closed window position, the inner sleeve having a tissue-resecting distal end and an interior lumen in fluid communication with a negative pressure source for aspiration of resected tissue through the interior lumen;
wherein the outer sleeve includes a closed distal tip at a distal end of the outer sleeve and a tissue displacement feature extending proximally from the closed distal tip;
wherein the tissue displacement feature is fixed relative to the outer sleeve;
wherein a proximal end of the tissue displacement feature is located proximal of a distal end of the tissue-receiving window and a distal end of the tissue displacement feature is located distal of the distal end of the tissue-receiving window;
wherein the tissue-receiving window extends around a portion of a circumference of the outer sleeve, and a distal portion of the tissue-receiving window extends further around the circumference of the outer sleeve than a proximal portion of the tissue-receiving window.
17. The tissue resecting device of claim 16 , wherein the tissue-resecting distal end extends distally of the distal end of the tissue-receiving window in the closed window position.
18. The tissue resecting device of claim 17 , wherein the tissue displacement feature extends into the interior lumen of the inner sleeve in the closed window position.
19. The tissue resecting device of claim 16 , wherein the tissue-resecting distal end includes an RF electrode operatively coupled to an RF source configured to create a plasma around an edge of the RF electrode.
20. The tissue resecting device of claim 16 , further comprising a motor drive configured to axially reciprocate the inner sleeve between the open window position and the closed window position.