MULTIFUNCTION CANNULA TOOLS

• US 20080243030A1
• Filed: 04/02/2007
• Published: 10/02/2008
• Est. Priority Date: 04/02/2007
• Status: Abandoned Application

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Seibel, Eric J., Melville, Charles David
• Application Number:
  US11/695,175
• Publication Number:
  US 20080243030A1
• Time in Patent Office: Days
• US Class Current: 600/566
• CPC Class Codes: A61B 10/02 Instruments for taking cell samples or for biopsy A61B10/0038 and A61B10/0045 take precedence; needle locating or guiding means A61B17/3403; samplers for enzymology or microbiology C12M1/26; sampling or preparing biological specimens G01N33/48
• CPC Class Codes: A61B 10/0283 with vacuum aspiration, e.g. caused by retractable plunger or by connected syringe A61B10/025, A61B10/0266 take precedence
• CPC Class Codes: A61B 10/04 Endoscopic instruments
• CPC Class Codes: A61B 2017/320004 abrasive
• CPC Class Codes: A61B 2018/1407 Loop

Abstract

Different exemplary embodiments of cannula tools each perform multiple functions. Each cannula tool is able to dislodge or cut away a biopsy sample from a desired site within a patient'"'"'s body, and then collect the sample. The cannula tool, which is disposed at the distal end of an elongate flexible tube is guided to the desired site over a guide wire. The cannula tool either abrades cells from adjacent tissue with an abrasive surface, or cuts away a sample of tissue with a sharpened cutting edge or with a loop that is electrically heated or pulled to snare the sample. The biopsy sample is then drawn with a bodily fluid or introduced fluid through an annulus formed between the guide wire and the inner surface of the elongate flexible tube or through a lumen, for collection at the proximal end of the elongate flexible tube.

Claims

1. A cannula tool system for taking a sample of cells or tissue at an internal site within a body of a patient, comprising:

(a) an elongate tubular member having at least one lumen that is sized and configured to slip longitudinally over a guide that has been inserted into a body of a patient, so that the elongate tubular member is controllably advanced over the guide to a desired internal site within the body of the patient;

(b) means associated with the elongate tubular member for dislodging a biopsy sample from a desired internal site within a body of a patient; and

(c) means associated with the elongate tubular member for withdrawing the biopsy sample from a body of a patient for cytopathological evaluation.

2. The cannula tool system of claim 1, wherein the elongate tubular member extends between a proximal end and a distal end, wherein the means for withdrawing comprises a pump in fluid communication with a lumen formed within the elongate tubular member, said pump being configured for extracting the biopsy sample through the lumen from the distal end of the elongate tubular member by drawing the biopsy sample with a bodily fluid through the lumen, toward the proximal end of the elongate tubular member.

3. The cannula tool system of claim 2, wherein when the elongate tubular member is disposed proximate to tissue, the pump applies a negative pressure that draws the tissue toward or into the tube lumen.

4. The cannula tool system of claim 2, wherein the elongate tubular member has an exterior surface, and wherein the means for dislodging comprises a plurality of outwardly extending abrasive points disposed at spaced-apart positions on the exterior surface of the elongate tubular member, proximate to the distal end thereof, said abrasive points abrading cells from an internal site within a body of a patient.

5. The cannula tool system of claim 2, further comprising an annular gap that is defined between an interior surface of the lumen and the guide, wherein cells comprising the biopsy sample, which are dislodged from the internal site, are withdrawn from the internal site through the annular gap.

6. The cannula tool system of claim 5, wherein the annular gap is coupled in fluid communication with a source of a fluid that is introduced through the annular gap to dislodge and suspend the cells comprising the biopsy sample, through the annular gap.

7. The cannula tool system of claim 4, wherein the means for withdrawing further comprises a plurality of orifices formed in the elongate tubular member proximate to the spaced-apart positions where the plurality of outwardly extending abrasive points are disposed, so that the plurality of orifices provide fluid communication paths for cells conveyed with a bodily fluid to pass into the lumen of the elongate tubular member and be drawn by the pump through the lumen toward the proximal end of the elongate tubular member.

8. The cannula tool system of claim 7, wherein an annular gap is formed between the guide and an interior surface of the lumen, so that cells conveyed by bodily fluid are conveyed through the annular gap from the plurality of orifices to the proximal end of the elongate tubular member.

9. The cannula tool system of claim 2, wherein the means for dislodging comprises a snare loop that extends generally distal of the distal end of the elongate tubular member, the snare loop being employed to cut away tissue comprising the biopsy sample from an internal site within a body of a patient.

10. The cannula tool system of claim 9, wherein the pump applies a negative pressure to tissue that is adjacent to the snare loop, to draw said tissue into the snare loop while the snare loop has a larger diameter, so that the tissue drawn into the snare loop is cut away when the snare loop is drawn to a smaller diameter.

11. The cannula tool system of claim 9, wherein the snare loop is coupled to a power supply that is selectively activated to heat the snare loop with an electrical current sufficiently to cut through tissue, thereby freeing the biopsy sample from adjacent tissue, the tissue that is freed from the adjacent tissue being drawn with bodily fluid into and through the lumen of the elongate tubular member.

12. The cannula tool system of claim 9, wherein the snare loop is coupled to a line that extends proximally of the elongate tubular member and is pulled to tighten the snare loop around tissue to cut the tissue from adjacent tissue, so that the tissue freed from the adjacent tissue can be drawn into and through the elongate tubular member toward the proximal end of the elongate tubular member.

13. The cannula tool system of claim 2, wherein the means for dislodging comprises a helical member having a cutting blade formed on its distal end and disposed in the lumen of the elongate tubular member, within an annular gap defined between an interior surface of the elongate tubular member and the guide, rotation of the elongate tubular member about the guide causing the cutting blade to cut free a piece of tissue comprising the biopsy sample at an internal site within a body of a patient, the piece of tissue being then drawn into and through the annular gap toward the proximal end of the elongate tubular member.

14. The cannula tool system of claim 13, further comprising a prime mover, and a rotational driver that is configured to drivingly couple with the elongate tubular member where exposed outside a body of a patient, the prime mover causing the rotational driver to rotate the elongate tubular member about the guide so that the cutting blade is rotated into tissue to cut away the piece of tissue.

15. The cannula tool system of claim 13, further comprising an annular gap formed between an interior surface of the lumen and the guide, wherein the piece of tissue that is cut away is drawn through the annular gap by a negative pressure produced by the pump.

16. The cannula tool system of claim 2, further comprising a biopsy trap disposed between and in fluid communication with the pump and the proximal end of the elongate tubular member, the biopsy trap serving to trap the biopsy sample after it exits from the elongate tubular member.

17. The cannula tool system of claim 2, wherein the means for dislodging comprises a balloon that is disposed around an exterior of the elongate tubular member adjacent to the distal end of the elongate tubular member, an outer surface of the balloon having an abrasive coating so that when the balloon is selectively inflated while the distal end of the elongate tubular member is disposed at an internal site with a body of a patient, and the elongate tubular member is moved while the abrasive coating is in contact with tissue at the internal site, cells are dislodged from the tissue by the abrasive coating on the balloon and are drawn with the bodily fluid into and through the lumen of the elongate tubular member by the pump, toward the proximal end of the elongate tubular member.

18. The cannula tool system of claim 17, wherein the cells that are dislodged are drawn through an annular gap defined between an interior surface of the lumen and the guide.

19. The cannula tool system of claim 2, further comprising an outer elongate sheath that is movable between a first position that protects the means for dislodging during insertion and retraction of the elongate flexible member within a body of a patient, and a second position that exposes the means for dislodging the biopsy sample, when the means for dislodging is disposed at the desired internal site.

20. The cannula tool system of claim 19, wherein the outer elongate sheath extends proximally and is pulled proximally to achieve the second position in which the means for dislodging are exposed.

21. The cannula tool system of claim 19, wherein the outer elongate sheath extends proximally and is rotated relative to the cannula tool to achieve the second position in which the means for dislodging are exposed.

22. The cannula tool system of claim 2, wherein the elongate tubular member includes a guide collar disposed proximate to the distal end of the elongate tubular member, the guide collar being attached to one side of the elongate tubular member and having a second lumen formed within the guide collar, the second lumen comprising the at least one lumen that is sized and configured to slide over the guide.

23. The cannula tool system of claim 22, wherein the distal end of the elongate tubular member includes a sharp cutting edge that slices a piece of tissue free from adjacent tissue, the piece of tissue comprising the biopsy sample, the biopsy sample being conveyed by the pump, into and through the lumen, toward the proximal end of the elongate tubular member.

24. The cannula tool system of claim 1, wherein the guide comprises an elongate flexible member selected from a group consisting of:

(a) an endoscope;

(b) a catheter; and

(c) a flexible guidewire.

25. A multifunctional cannula tool for carrying out a plurality of functions, the multifunctional cannula tool comprising:

(a) an elongate tubular body having a proximal end that remains external to a body of a patient, and a distal end that is configured to be inserted into a body of a patient, the elongate tubular body including a guide lumen that is sized and configured to slide over a flexible guide member, to advance the distal end of the elongate tubular body to an internal site within a body of a patient;

(b) a dislodgment portion of the elongate tubular body that is configured to dislodge at least one of cells and tissue and which is disposed proximate to the distal end of the elongate tubular body; and

(c) a passage formed within the elongate tubular body and defining a fluid path through which said at least one of cells and tissue that are dislodged from the internal site to which the distal end of the elongate tubular body has been advanced, are drawn toward the proximal end of the elongate tubular body for collection as a biopsy sample.

26. The multifunctional cannula tool of claim 25, wherein the dislodgment portion comprises an abrasive surface that is configured to abrade cells from tissue that is adjacent to the distal end of the elongate tubular body, so that cells thus freed from the tissue can be drawn through the passage formed within the elongate tubular body and collected as a biopsy sample.

27. The multifunctional cannula tool of claim 26, further comprising a pressurized fluid lumen that is configured to convey a pressurized fluid to the distal end of the elongate tubular body from an external source of pressurized fluid, wherein the dislodgment portion further includes a selectively inflatable membrane on which the abrasive surface is disposed, the selectively inflatable membrane extending at least partially around a circumference of the elongate tubular body and being disposed adjacent to the distal end of the elongate tubular body, so that when the inflatable membrane is selectively expanded outwardly by being inflated with a pressurized fluid conveyed through the pressurized fluid lumen, and the elongate tubular body is then moved relative to tissue contacted by the abrasive surface, the abrasive surface on the inflatable membrane abrades cells from the tissue thus contacted by the abrasive surface, for collection as the biopsy sample.

28. The multifunctional cannula tool of claim 26, wherein the abrasive surface comprises a plurality of spaced-apart points that extend outwardly from an exterior of the elongate tubular body, near its distal end, and configured so that when the elongate tubular body is moved relative to tissue contacted by the spaced-apart points, said points abrade cells from the tissue contacted, freeing cells to be drawn into the passage and collected at the proximal end of the elongate tubular body as a biopsy sample.

29. The multifunctional cannula tool of claim 25, wherein the dislodgment portion comprises a loop disposed adjacent to the distal end of the elongate tubular body, said loop being configured and adapted to snare tissue disposed proximate thereto, detaching the tissue that is snared, so that the tissue can be drawn into and conveyed through the passage, and collected at the proximal end of the elongate tubular body as a biopsy sample.

30. The multifunctional cannula tool of claim 29, further comprising electrical leads that extend from the proximal end, distally along the elongate tubular body, and which are connected to the loop, proximal ends of said leads being adapted to connect to a power supply that selectively supplies an electrical current to the loop to heat the loop sufficiently to cut through tissue snared by the loop, so that the tissue is freed.

31. The multifunctional cannula tool of claim 29, wherein the loop is coupled to a wire that extends proximally of the elongate tubular body, an end of the wire that extends externally from the proximal end of the elongate tubular body being adapted to be pulled proximally to reduce a size of the loop so that the loop cuts free the tissue that is snared by the loop for collection as a biopsy sample.

32. The multifunctional cannula tool of claim 25, wherein the dislodgment portion comprises a cutting edge that is disposed adjacent to the distal end of the elongate tubular body, said cutting edge being adapted to cut tissue free for collection as a biopsy sample.

33. The multifunctional cannula tool of claim 32, wherein the cutting edge is disposed at a distal end of a helical corkscrew cutting blade that is disposed within the passage, so that tissue cut away with the cutting edge is drawn through the passage for collection at the proximal end of the elongate tubular body, as a biopsy sample.

34. The multifunctional cannula tool of claim 32, wherein the cutting edge is disposed at a leading distal edge of the passage, and wherein the guide lumen comprises a relatively shorter section of a tubular member that extends generally parallel to the elongate tubular body and is attached along a side of the passage.

35. The multifunctional cannula tool of claim 32, wherein the passage comprises an annular gap defined between an interior surface of the elongate tubular body and a flexible guidewire, a biopsy sample being withdrawn through the annular gap.

36. A method for using a cannula tool to carry out multiple functions within a body of a patient, comprising the steps of:

(a) inserting a flexible guide into the body of the patient and maneuvering a distal end of the flexible guide to a defined location;

(b) sliding a hollow cannula tool comprising an elongate tubular body over the flexible guide, until a distal end of the elongate tubular body is disposed at a desired site within the body of the patient;

(c) using a portion of the cannula tool disposed proximate to the distal end of the elongate tubular body, dislodging cells or tissue from the desired site; and

(d) at a proximal end of the elongate tubular body, collecting a biopsy sample comprising the cells or tissue that were dislodged, by drawing the cells or tissue that were dislodged through a passage formed in the cannula tool, toward a proximal end of the elongate tubular body, for withdrawal from the passage.

37. The method of claim 36, wherein the step of dislodging comprises the step of abrading cells from tissue within the body of the patient using an abrasive surface disposed adjacent to the distal end of the elongate tubular body.

38. The method of claim 37, wherein the abrasive surface comprises a plurality of sharp points that are spaced apart on an exterior of the elongate tubular body, adjacent to its distal end, further comprising the step of moving the elongate tubular body relative to adjacent tissue so the cells are abraded from and freed from the tissue by the plurality of sharp points.

39. The method of claim 37, wherein the abrasive surface is formed on a flexible membrane, further comprising the steps of:

(a) selectively expanding the flexible membrane outwardly until the abrasive surface on the flexible membrane contacts adjacent tissue; and

(b) then moving the abrasive surface on the elongate tubular body relative to the adjacent tissue, to abrade cells from the adjacent tissue.

40. The method of claim 36, wherein the step of dislodging comprises the step of snaring and cutting tissue from the desired site using a loop disposed at the distal end of the elongate tubular body.

41. The method of claim 40, wherein the step of snaring and cutting the tissue comprises the step of heating the loop to cut through the tissue that is snared, to free the tissue from adjacent tissue.

42. The method of claim 40, wherein the step of snaring and cutting the tissue comprises the step of reducing a size of the loop, causing the loop to cut away the tissue that is snared, to free said tissue from adjacent tissue.

43. The method of claim 36, further comprising the step of applying a negative pressure to a proximal portion of the cannula tool to withdraw tissue that has been dislodged at the distal end of the elongate tubular body, out through the passage.

44. The method of claim 36, further comprising the steps of selectively protecting the portion of the cannula tool when it is being advanced to the desired site;

and selectively exposing the portion of the cannula tool to dislodge the biopsy sample at the desired site.

45. The method of claim 36, wherein the step of dislodging comprises the step of cutting away a piece of tissue from the desired site with a cutting blade disposed at the distal end of the elongate tubular body.