Biopsy systems and methods

Abstract

A percutaneous access system is disclosed that includes a needle and an inner cannula. The needle includes an internal passageway. At a distal end, the needle includes an expandable section. A distal section of the internal passageway of the needle, which corresponds to the expandable section, is tapered to enable the expandable section to expand and collapse as the inner cannula is positioned within and/or moves through the tapered distal section. The inner cannula may enable grasping and/or aspiration of a sample from a location of interest within a subject's body. Biopsy methods are also disclosed.

Claims

1. A biopsy system, comprising: a percutaneous biopsy needle with an internal passageway extending through a length thereof, the internal passageway including a tapered section within an expandable section at a distal portion of the percutaneous biopsy needle, the expandable section including a plurality of leaves that are circumferentially adjacent to one another; an inner cannula capable of movement through the internal passageway through the percutaneous biopsy needle, a distal portion of the inner cannula positionable within the tapered section of the internal passageway in a manner that can force the plurality of leaves of the expandable section radially outward; and a housing that can rotate the inner cannula as the inner cannula is forced into and/or out of the internal passageway through the percutaneous biopsy needle.

2. The biopsy system of claim 1, wherein at least one leaf of the plurality of leaves includes a sharpened edge.

3. The biopsy system of claim 2, wherein at least one slot extends through the distal portion of the inner cannula, the at least one slot that can receive a sample and to pull the sample across the sharpened edge of the at least one leaf as the inner cannula rotates within the internal passageway of the percutaneous biopsy needle.

4. The biopsy system of claim 1, wherein a distal end of the inner cannula is sharpened to enable the distal end to obtain a core sample.

5. The biopsy system of claim 1, wherein the housing can lock the inner cannula into place in at least one position along the length of the percutaneous biopsy needle.

6. The biopsy system of claim 5, wherein the housing can lock the inner cannula into place in a distal-most position, in which a distal end of the inner cannula protrudes beyond a distal end of the percutaneous biopsy needle.

7. The biopsy system of claim 1, further comprising: an elastic closure over a proximal portion of the expandable section of the percutaneous biopsy needle in a manner that enables the plurality of leaves to collapse upon removal of the distal portion of the inner cannula from the tapered section of the internal passageway through the percutaneous biopsy needle.

8. The biopsy system of claim 1, wherein the tapered section of the internal passageway of the percutaneous biopsy needle includes a plurality of different tapers.

9. A percutaneous access system, comprising: a needle with an internal passageway extending through a length thereof, the internal passageway including a tapered section within an expandable section at a distal portion of the needle, the expandable section including a plurality of leaves that are circumferentially adjacent to one another; an inner cannula movable through the internal passageway through the needle, a distal portion of the inner cannula positionable within the tapered section of the internal passageway in a manner that can force the plurality of leaves of the expandable section radially outward; and an elastic closure over a proximal portion of the expandable section of the needle to enable the plurality of leaves to collapse upon removal of the distal portion of the inner cannula from the tapered section of the internal passageway through the needle.

10. The percutaneous access system of claim 9, wherein at least one leaf of the plurality of leaves includes a sharpened edge.

11. The percutaneous access system of claim 10, wherein at least one slot extends through the distal portion of the inner cannula, the at least one slot able to receive a sample and of pulling the sample across the sharpened edge of the at least one leaf as the inner cannula rotates within the internal passageway of the needle.

12. The percutaneous access system of claim 9, wherein a distal end of the inner cannula is sharpened to enable the distal end to obtain a core sample.

13. The percutaneous access system of claim 9, wherein the the inner cannula is lockable into place in at least one position along the length of the needle.

14. The percutaneous access system of claim 13, wherein the inner cannula is lockable into place in a distal-most position, in which a distal end of the inner cannula protrudes beyond a distal end of the needle.

15. A method for obtaining a sample from within a subject's body, comprising: introducing a distal portion of a needle through skin of the subject to a site of interest within a body of the subject; causing an expandable section of the needle to expand by moving an inner cannula distally within the needle; causing a distal end of the expandable section of the needle to receive a sample from the site of interest; causing the expandable section of the needle to collapse onto at least a portion of the sample, including moving the inner cannula proximally within the needle; and removing the needle and the sample from the body of the subject.

16. The method of claim 15, wherein removing the sample from the body of the subject includes applying suction to the needle.

17. The method of claim 15, wherein removing the sample from the body of the subject includes pulling the distal portion of the needle from the body and the skin of the subject.

18. The method of claim 17, wherein removing the sample from the body of the subject further includes applying suction to the needle.

19. The method of claim 15, further comprising: rotating the inner cannula within the needle to sever the sample from the site of interest.

20. The method of claim 19, further comprising: locking and/or unlocking rotation of the inner cannula within the needle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 is a side view of an embodiment of the percutaneous biopsy system according to this disclosure;

(3) FIG. 2 is an exploded view showing various elements of the percutaneous biopsy system of FIG. 1;

(4) FIG. 3 illustrates an embodiment of an internal passageway through an expandable section of a percutaneous biopsy needle, which includes regions with different tapers;

(5) FIG. 4 depicts an embodiment of the percutaneous biopsy needle and inner cannula that are configured to cut and aspirate;

(6) FIGS. 5 and 6 are perspective views of an expandable section of the percutaneous biopsy needle and an elastic sleeve that surrounds a proximal portion of the expandable section, respectively showing the expandable section in collapsed and expanded states; and

(7) FIG. 7 shows an embodiment of an inner cannula that is configured to obtain a core sample from a tissue or other item of interest.

DETAILED DESCRIPTION

(8) With reference to FIGS. 1 and 2, an embodiment of a biopsy system 10 according to this disclosure is depicted. The biopsy system 10 includes a percutaneous biopsy needle 20, an inner cannula 50, a main body 60, a distal hub 70 and a proximal hub 80.

(9) The percutaneous biopsy needle 20 may be configured like the micro-taper needle of U.S. Pat. No. 7,803,142, the entire disclosure of which is incorporated herein by this reference. More specifically, the percutaneous biopsy needle 20 may include a proximal end 22 and a distal end 24. An expandable section 25 may extend proximally from the distal end 24 of the percutaneous biopsy needle 20 to an intermediate location along its length. The expandable section 25 may include a plurality of slits 26 (FIGS. 3, 5 and 6) that extend through the thickness of a wall of the percutaneous biopsy needle 20, which extend along the length of the expandable section 25 and are spaced apart at different locations around the circumference of the expandable section 25. The slits 26 may separate the expandable section 25 into a plurality of expandable elements, which are also referred to herein as “leaves” 27.

(10) In some embodiments, such as that depicted by FIGS. 1 and 2, the expandable section 25 may comprise a tapered portion of the percutaneous biopsy needle 20. More specifically, a proximal portion of the percutaneous biopsy needle 20 may have a constant outer diameter (i.e., it may be straight, or untampered), while the expandable section 25 or a portion thereof is tapered. As illustrated, an outer diameter of the percutaneous biopsy needle 20 may taper from a relatively large dimension at a proximal side of the taper (e.g. at a proximal side of the expandable section 25, etc.) to a smaller dimension at a distal side of the taper (e.g., at the distal end 24 of the percutaneous biopsy needle 20, etc.). In a specific embodiment, the relatively large dimension may be 18 gauge (0.049 inch) or larger, while the smaller dimension may be 21 gauge (0.032 inch) or smaller (e.g., 22 gauge, 25 gauge, etc.).

(11) As illustrated by FIG. 3, an inner diameter of an expandable section 35 of an internal passageway 30, which resides within a tapered portion (e.g., the expandable section 25, etc.) of the percutaneous biopsy needle 20, may also include one or more tapers. In a specific embodiment, where the outer diameter of the percutaneous biopsy needle 20 tapers from 18 gauge to 21 gauge, the inner diameter of the corresponding expandable section 35 of its internal passageway 30 may taper from 0.039 inch to 0.022 inch. In such an embodiment, as an elongated instrument (e.g., a wire, an inner cannula 50, etc.) with an outer diameter that exceeds the inner diameter of any portion of the expandable section 35 moves distally through the internal passageway 30, the elongated instrument will force the leaves 27 outward, expanding the expandable section 25 (FIGS. 1 and 2). Expansion of the expandable section 25 includes an effective expansion of the inner diameter of the expandable section 35 of the internal passageway 30 within the expandable section 25 of the percutaneous biopsy needle 20 and an increase in the outer diameter of the expandable section 25.

(12) In some embodiments, tapering of the expandable section 35 of the internal passageway 30 that resides within the expandable section 25 of a percutaneous biopsy needle 20 may be varied. For example, the expandable section 35 of the internal passageway 30 may include at least one tapered portion and at least one straight portion. As another example, the expandable section 35 of the internal passageway 30 may include portions with different tapers. Without limitation, FIG. 3 illustrates an embodiment in which a proximal taper 36 of the expandable section 35 of an internal passageway 30 is configured to cause the expandable section 25 (FIGS. 1 and 2) of the percutaneous biopsy needle 20 (FIGS. 1 and 2) to expand in such a way that an outer diameter of the distal end 24 (FIGS. 1 and 2) of the percutaneous biopsy needle 20 increases to a first dimension, while a distal taper 37 (which may comprise an inner diameter that decreases from a proximal side of the distal taper 37 to a distal side of the distal taper 37) of the expandable section 35 of the internal passageway 30 may enable the expanded outer diameter of the distal end 24 of the percutaneous biopsy needle 20 to remain the same while an elongated instrument continues to advance distally through the internal passageway 30. Of course, other variations in the manner in which the expandable section 35 of the internal passageway 30 through the expandable section 25 of a percutaneous biopsy needle 20 tapers, as well as variations in the outer diameter of an elongated instrument that may be moved through the expandable section 35 of the internal passageway 30, may enable the expandable section 25 of the percutaneous biopsy needle 20 to expand and/or collapse in any desired fashion as the elongated instrument moves through the internal passageway 30, or at least through the expandable section 35 of the internal passageway 30.

(13) Turning briefly to FIG. 4, an embodiment of a percutaneous biopsy needle 20″ with leaves 27″ that have sharpened edges 28″ is depicted. In some embodiments, the sharpened edge 28″ of a leaf 27″ may include serrations. As the leaves 27″ of such a percutaneous biopsy needle 20″ are expanded, their sharpened edges 28″ are exposed, which may enable use of such a percutaneous biopsy needle 20″ to cut into an obstruction or a sample (e.g., tissue, etc.) as the percutaneous biopsy needle 20″ is rotated in an appropriate direction (e.g., with a sharpened edge 28″ leading) or as the obstruction or sample is pulled in an appropriate direction (e.g., against the sharpened edge 28″, etc.).

(14) With returned reference to FIGS. 1 and 2, a biopsy system 10 may include an elastic sleeve 40 that surrounds at least a proximal portion of the expandable element 25 of the percutaneous biopsy needle 20. In some embodiments, the elastic sleeve 40 may extend from a location at or adjacent to the proximal end 22 of the percutaneous biopsy needle 20 to a location somewhat proximal to the distal end 24 of the percutaneous biopsy needle 20. Without limitation, a distal end of the elastic sleeve 40 may be located about 1 cm or about a quarter inch (¼ inch) proximal to the distal end 24 of the percutaneous biopsy needle 20.

(15) The elastic sleeve 40 may be formed from a material that will enable it to conform to the shape and dimensions of the portions (e.g., a proximal portion of the expandable section 25, etc.) of the percutaneous biopsy needle 20 over which it is positioned. The material of the elastic sleeve 40, as well as its dimensions (e.g., its thickness, etc.), may enable the elastic sleeve 40 to expand while the expandable section 25 expands, and to contract upon removal of an expansion force (e.g., partial or complete removal of an elongated instrument, etc.) from the expandable section 25. As the elastic sleeve 40 contracts, it may force the leaves 27 of the expandable section 25 radially inward toward or to their original positions, thereby collapsing the expandable section 25 and, when the expansion force is totally removed therefrom, enabling the expandable section 25 to return to its collapsed state. The material from which the elastic sleeve 40 is formed, along with its dimensions, may also enable it to maintain its integrity when expanded and contracted, without significantly impeding insertion of the percutaneous biopsy needle 20 into and through a subject's skin. Suitable materials for use as the elastic sleeve 40 include, but are not limited to, dip molded elastomers and heat shrink elastomers, including elastomeric fluoropolymers. The thickness of the elastic sleeve 40 may be about 0.00025 inch to about 0.0025 inch (e.g., about 0.001 inch, etc.). FIGS. 5 and 6 respectively show an expandable section 25 of the percutaneous biopsy needle 20 in collapsed and expanded states.

(16) As an alternative to the sleeve 40, or in addition thereto, the expandable section 25 of the percutaneous biopsy needle 20 may be formed from a material that will resiliently return to its original shape (i.e., that will enable the leaves 27 to collapse) once an expansion force (e.g., an elongated instrument, etc.) is partially or completely removed from the expandable section 25. Spring steel and nitinol are non-limiting examples of such a material.

(17) In the embodiment of biopsy system 10 illustrated by FIGS. 1 and 2, the elongated instrument that may cause the expandable section 25 of the percutaneous biopsy needle 20 to expand may comprise an inner cannula 50. The inner cannula 50 of a biopsy system 10 according to this disclosure includes a proximal end 52 and a distal end 54. The distal end 54 may be configured to fit within the internal passageway 30 through the percutaneous biopsy needle 20 and to be moved, or translated, along a length of the internal passageway 30, including through the expandable section 35 of the internal passageway 30. In the depicted embodiment, an outer diameter of a portion of the inner cannula 50 that resides within and/or is configured to be positioned within at least a portion of the internal passageway 30 through the percutaneous biopsy needle 20—i.e., a distal portion of the inner cannula 50—is uniform. In a specific embodiment, in which the inner cannula 50 may be translated through the length of an embodiment of percutaneous biopsy needle 20 having an 18 gauge maximum outer diameter, the outer diameter of the inner cannula 50 may be 0.038 inch. As this outer diameter is greater than the minimum inner diameter of the expandable section 35 of the internal passageway 30, as depicted by FIGS. 5 and 6, introducing the distal end 54 of the inner cannula 50 into the expandable section 35 will force to the leaves 27 of the expandable section 25 of the percutaneous biopsy needle 20 radially outward, enlarging the inner diameter of the expandable section 35 of the internal passageway 30 and expanding the outer diameter of the expandable section 25 of the percutaneous biopsy needle 20, particularly at its distal end 24.

(18) A channel 56 extends through the length of the inner cannula 50. When the inner cannula 50 is retracted (proximally), i.e., its distal end 54 is not coincident with or does not extend distally beyond the distal end 24 of the percutaneous biopsy needle 20, the channel 56 through the inner cannula 50 communicates with the internal passageway 30 through the percutaneous biopsy needle 20.

(19) In some embodiments, the distal end 54 of the inner cannula 50 may be blunt (e.g., flat, rounded, etc.). In other embodiments, such as that depicted by FIG. 7, the distal end 54′ of an inner cannula 50′ may be configured to cut into a sample or another item. More specifically, the distal end 54′ of such an inner cannula 50′ may a sharpened edge 55′, or a blade. In some embodiments, the sharpened edge 55′ may include serrations, which may enable the inner cannula 50′ to cut into tissue and, thus, enable the channel 56′ through the inner cannula 50′ to receive a core- or column-shaped sample of the tissue.

(20) With returned reference to FIG. 4, an inner cannula 50″ may include one or more apertures 58″ that, when positioned between adjacent, expanded leaves 27″, are configured to enable an obstruction, tissue or another sample to be drawn therein and, as the inner cannula 50″ rotates within the percutaneous biopsy needle 20″, to enable the obstruction, tissue, or other sample to be pulled against a sharpened edge 28″ of a leaf 27″ and, thus, aspirated into the channel 56″ through the inner cannula 50″.

(21) Referring again to FIGS. 1 and 2, a further description of the manner in which the percutaneous biopsy needle 20 and the inner cannula 50 are assembled with one another, and a description of the manner in which the percutaneous biopsy needle 20 and the inner cannula 50 function relative to one another are provided.

(22) A distal hub 70 may be secured to the proximal end 22 of the percutaneous biopsy needle 20 to facilitate assembly of the inner cannula 50 with the percutaneous biopsy needle 20. Specifically, the distal hub 70 may include a channel 76 that, at a distal side 74 of the distal hub 70, receives the proximal end 22 of the percutaneous biopsy needle 20. At a proximal side 72 of the distal hub 70, the channel 76 may be configured to enables alignment of the distal end 54 of the inner cannula 50 with the internal passageway 30 through the percutaneous biopsy needle 20.

(23) An O-ring 78 may be situated at the proximal side 72 of the distal hub 70 to provide a seal between the internal passageway 30 through the percutaneous biopsy needle 20 and the outer surface of the inner cannula 50. More specifically, the O-ring 78 may surround a circumference of the inner cannula 50 and enable axial movement of the inner cannula 50 into and out of the internal passageway 30 of the percutaneous biopsy needle 20. With this arrangement, the O-ring 78 may enable pressure to be applied to channel 56 through the inner cannula 50 and to the internal passageway 30 through the percutaneous biopsy needle 20, and prevent samples that are aspirated into the channel 56 of the inner cannula 50 from leaking into other parts of the biopsy system 10.

(24) The proximal side 72 of the distal hub 70 may also be configured to couple the percutaneous biopsy needle 20 to the main body 60 of the biopsy system 10. In a specific, but non-limiting embodiment, the proximal side 72 of the distal hub 70 may be configured to be received within an aperture 65 at a distal side 64 of the main body 60, and may be fixedly coupled to the main body 60 (e.g., mechanically, with a suitable glue or cement, etc.).

(25) The proximal side 62 of the main body 60 is configured to receive the proximal hub 80, which, in turn, is secured to the proximal end 52 of the inner cannula 50. In a specific embodiment, the proximal end 52 of the inner cannula 50 may be fixedly secured in place (e.g., mechanically, with a suitable glue or cement, etc.) within a channel 86 through the proximal hub 80 at a distal portion 84 of the proximal hub 80 in a manner that enables communication between the channel 56 through the inner cannula 50 and the channel 86 through the proximal hub 80.

(26) The distal portion 84 of the proximal hub 80 may be configured for receipt by a passage 66 through the main body 60 of the biopsy system 10. In the depicted embodiment, a retaining ring 69 may be configured to hold a distal-most end of the distal portion 84 of the proximal hub 80 in place within the passage 66 through the main body 60.

(27) In some embodiments, features 85 (e.g., one or more spiral protrusions, or threads, etc.) on an outer circumference of the distal portion 84 may cooperate with (e.g., be received by, etc.) cooperating features 67 (e.g., one or more spiral grooves, etc.) on an inner circumference of the passage 66 through the main body 60. With such an arrangement, the movement of the distal portion 84 of the proximal hub 80 and, thus, the movement of the inner cannula 50 into and out of the percutaneous biopsy needle 20, may be controlled (e.g., by rotation of the proximal hub 80 relative to the main body 60, etc.).

(28) In some embodiments, the distal portion 84 of the proximal hub 80, the retaining ring 69 and/or the passage 66 through the main body 60 may include one or more features 88, 68 that enable the proximal hub 80 to lock (rotationally and axially) in one or more positions (e.g., in a proximal position (i.e., with the inner cannula fully withdrawn (proximally) into the percutaneous biopsy needle 20), in one or more intermediate positions, in a distal position (i.e., with the inner cannula 50 fully extended (distally) from the percutaneous biopsy needle 20), etc.).

(29) On its proximal side 82, the proximal hub 80 may include one or more coupling features 83 configured to enable the biopsy system 10 to be secured to another apparatus. Without limitation, the coupling features 83 may comprise luer lock elements or other features that will enable the proximal hub 80 to be coupled to and uncoupled from another apparatus, such as an aspiration device.

(30) From the foregoing, various uses of the biopsy system 10, as disclosed above, should be apparent to those of ordinary skill in the art.

(31) Although the foregoing description sets forth many specifics, these should not be construed as limiting the scope of any of the claims, but merely as providing illustrations of some embodiments and variations of elements or features of the disclosed subject matter. Other embodiments of the disclosed subject matter may be devised which do not depart from the spirit or scope of any of the claims. Features from different embodiments may be employed in combination. Accordingly, the scope of each claim is limited only by its plain language and the legal equivalents thereto.