Biopsy device cannula seal

Abstract

The biopsy device includes an elongate housing having a manifold, an outer cannula slidably disposed partially within the manifold, and an inner cannula slidably disposed partially within the lumen of the outer cannula. The biopsy device further includes an outer cannula seal disposed between the manifold and the outer cannula, the outer cannula seal including an interference ring portion disposed adjacent an inner surface of the manifold, a beaded ring portion contacting an outer surface of the outer cannula, and a flexible portion extending between the interference ring portion and the beaded ring portion.

Description

Technical Field

[0001] (Related Application) This disclosure claims priority to U.S. Provisional Patent Application No. 62 / 940,616, filed on November 26, 2019, entitled "BIOPSY DEVICE CANNULA SEAL", under Attorney Docket No. BSH.0170.01 PRO, which is hereby incorporated by reference in its entirety as if fully set forth herein. The subject matter of this application relates to the subject matter disclosed and described in U.S. Patent No. 10,022,110, which is hereby incorporated by reference in its entirety as if fully set forth herein. (Technical Field)

[0002] This disclosure generally relates to a liquid-tight seal for use in a biopsy device needle set.

Background Art

[0003] In the practice of diagnostic medicine, it is often necessary or desirable to perform a biopsy or sample tissue selected from a living patient for medical evaluation. Cytological and histological studies of the biopsy sample can then be performed as an aid in the diagnosis and treatment of disease. Biopsies can be useful in diagnosing and treating not only various forms of cancer, but also other diseases in which a local area of affected tissue can be identified.

[0004] Biopsies are routinely performed on tissue using a needle set. One known needle set includes an outer cannula having a tip and a tissue receiving aperture defined near its distal end, and an inner cannula having an open distal end surrounded by an annular cutting blade. The inner cannula is slidably disposed within the outer cannula such that the inner cannula closes the tissue receiving aperture and can thereby cut tissue that escapes into the lumen of the outer cannula through the tissue receiving aperture. Typically, a hub is connected to the proximal end of each needle. Such needle sets are used with or incorporated into various forms of biopsy devices, including both manual and motor-driven biopsy devices.

[0005] Current needle sets include one or more O-rings in an attempt to provide a liquid-tight seal between various surfaces. However, the O-rings may not be able to maintain a liquid-tight seal, particularly due to movement of the various needle set components (e.g., the outer and / or inner cannulas) that contact the O-rings. Further, lateral movement of the outer and / or inner cannulas can also compromise the liquid-tight seal. Additionally, the O-rings create a seal using a friction fit (e.g., against the outer and / or inner cannulas). Thus, when those outer and / or inner cannulas move relative to the O-rings, the O-rings exert a resistance force against the outer and / or inner cannulas. This resistance force reduces the efficiency of the biopsy device into which the needle set is incorporated. The resistance force worsens with large longitudinal displacements of the outer and / or inner cannulas during a biopsy. The limitations when using O-rings within a needle set as described above also apply to other conventional seals such as “X” profile and edge type seals. SUMMARY OF THE INVENTION MEANS FOR SOLVING THE PROBLEM

[0006] According to one embodiment, the biopsy device includes an elongated housing having a manifold, an outer cannula disposed partially and slidably within the manifold, and an inner cannula disposed partially and slidably within the lumen of the outer cannula. The biopsy device further includes an outer cannula seal disposed between the manifold and the outer cannula, the outer cannula seal including an interference ring portion disposed adjacent to the inner surface of the manifold, a beaded ring portion in contact with the outer surface of the outer cannula, and a flexible portion extending between the interference ring portion and the beaded ring portion.

[0007] In one or more embodiments, the outer cannula seal is configured to allow longitudinal movement of the outer cannula relative to the manifold while maintaining a liquid-tight seal therebetween. The outer cannula seal may have a partial conical shape or a V-shaped cross-section. The biopsy device may include a manifold cap coupled to the distal end of the manifold, the manifold cap and the manifold together defining an annular space adjacent to the distal end of the manifold, and the interference ring portion of the outer cannula seal being at least partially disposed within the annular space. The interference ring portion of the outer cannula seal may form an interference fit between the inner surface of the manifold and the inner surface of the manifold cap. The interference ring portion of the outer cannula seal may define a distal-facing annular detent configured to engage an annular edge facing proximally of the manifold cap.

[0008] In one or more embodiments, the flexible portion of the outer cannula seal is biased to apply a force to the outer surface of the outer cannula against the beaded ring portion to create a liquid-tight seal between the beaded ring portion and the outer surface of the outer cannula. The flexible portion of the outer cannula seal may be configured to allow the interference ring portion and the beaded ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the outer cannula and the manifold. The outer cannula seal may include an ethylene propylene diene monomer (''EPDM'') polymer. The outer cannula seal may be manufactured using a molding process.

[0009] According to one embodiment, a biopsy device includes an elongated housing having a seal sleeve, an outer cannula hub coupled to a proximal end of the outer cannula, the outer cannula hub being partially and slidably disposed within the seal sleeve, and an inner cannula partially and slidably disposed within the lumen of the outer cannula. The biopsy device further includes an inner cannula seal disposed between the seal sleeve and the inner cannula, the inner cannula seal including an interference ring portion disposed adjacent to the inner surface of the seal sleeve, a beaded ring portion in contact with the outer surface of the inner cannula, and a flexible portion extending between the interference ring portion and the beaded ring portion.

[0010] In one or more embodiments, the inner cannula seal is configured to allow longitudinal movement of the inner cannula relative to the seal sleeve while maintaining a liquid-tight seal therebetween. The inner cannula seal may have a partial conical shape or a J-shaped cross-section. The proximal end of the outer cannula hub may define an annular groove adjacent to the distal end of the seal sleeve, and the interference ring portion of the inner cannula seal is at least partially disposed within the annular groove. The interference ring portion of the inner cannula seal may form an interference fit within the annular groove. The inner cannula seal may also include an intermediate beaded ring portion extending from the outer surface of the flexible portion.

[0011] In one or more embodiments, the flexible portion of the inner cannula seal biases a beaded ring portion to apply a force against the outer surface of the inner cannula to create a liquid-tight seal between the beaded ring portion and the outer surface of the inner cannula. The flexible portion of the inner cannula seal can be configured to allow the interference ring portion and the beaded ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the inner cannula and the seal sleeve. The inner cannula seal can include an ethylene propylene diene monomer ( "EPDM") polymer. The inner cannula seal can be manufactured using a molding process.

[0012] According to yet another embodiment, the biopsy device includes an elongated housing that includes a saline return fitting, an outer cannula that is partially and slidably disposed within the elongated housing, and an inner cannula that is partially and slidably disposed within each of the lumens of the outer cannula and the saline return fitting. The biopsy device further includes an inner cannula seal disposed between the inner wall of the saline return fitting and the inner cannula, the inner cannula seal including an interference ring portion disposed adjacent to the inner surface of the saline return fitting, a beaded ring portion in contact with the outer surface of the inner cannula, and a flexible portion extending between the interference ring portion and the beaded ring portion.

[0013] In one or more embodiments, the inner cannula seal is configured to allow longitudinal movement of the inner cannula relative to the saline return fitting while maintaining a liquid-tight seal therebetween. The inner cannula seal may have a partial conical shape or a J-shaped cross-section. The biopsy device may also include a saline return fitting cap coupled to the distal end of the saline return fitting, wherein the proximal end of the saline return fitting cap defines an annular groove adjacent to the distal end of the saline return fitting, and the interference ring portion of the inner cannula seal is disposed at least partially within the annular groove. The interference ring portion of the inner cannula seal may be disposed at least partially within the annular groove. The inner cannula seal may also include an intermediate beaded ring portion extending from the outer surface of the flexible portion.

[0014] In one or more embodiments, the flexible portion of the inner cannula seal is biased to apply a force against the outer surface of the inner cannula to the beaded ring portion, creating a liquid-tight seal between the beaded ring portion and the outer surface of the inner cannula. The flexible portion of the inner cannula seal may be configured to allow the interference ring portion and the beaded ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the inner cannula and the saline return fitting. The inner cannula seal may include an ethylene propylene diene monomer (''EPDM'') polymer. The inner cannula seal may be manufactured using a molding process.

[0015] Other and further aspects and features of embodiments of the disclosed invention will become apparent from the following detailed description when considered in conjunction with the accompanying figures. The present invention provides, for example, the following. (Item 1) A biopsy device, wherein the biopsy device has an elongated housing with a manifold, an outer cannula disposed partially and slidably within the manifold, an inner cannula disposed partially and slidably within the lumen of the outer cannula, and an outer cannula seal disposed between the manifold and the outer cannula and the outer cannula seal has an interference ring portion disposed adjacent to the inner surface of the manifold, a beaded ring portion in contact with the outer surface of the outer cannula, and a flexible portion extending between the interference ring portion and the beaded ring portion and is a biopsy device. (Item 2) The biopsy device according to Item 1, wherein the outer cannula seal is configured to maintain a liquid-tight seal between them while allowing longitudinal movement of the outer cannula relative to the manifold. (Item 3) The biopsy device according to Item 1, wherein the outer cannula seal has a partial conical shape. (Item 4) The biopsy device according to Item 1, wherein the outer cannula seal has a V-shaped cross-section. (Item 5) The biopsy device according to Item 1, further comprising a manifold cap coupled to the distal end of the manifold, the manifold cap and the manifold together defining an annular space adjacent to the distal end of the manifold, and the interference ring portion of the outer cannula seal being at least partially disposed within the annular space. (Item 6) The biopsy device according to Item 5, wherein the interference ring portion of the outer cannula seal forms an interference fit between the inner surface of the manifold and the inner surface of the manifold cap. (Item 7) The biopsy device according to Item 5, wherein the interference ring portion of the outer cannula seal defines a distal-facing annular detent configured to engage an annular edge facing proximal of the manifold cap. (Item 8) The biopsy device according to Item 1, wherein the flexible portion of the outer cannula seal is biased to apply a force to the beaded ring portion against the outer surface of the outer cannula to create a liquid-tight seal between the beaded ring portion and the outer surface of the outer cannula. (Item 9) The flexible portion of the outer cannula seal is configured to allow the interference ring portion and the beaded ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the outer cannula and the manifold. The biopsy device according to item 1. (Item 10) The outer cannula seal comprises an ethylene propylene diene monomer (''EPDM'') polymer. The biopsy device according to item 1. (Item 11) The outer cannula seal is manufactured using a molding process. The biopsy device according to item 1. (Item 12) A biopsy device, the biopsy device comprising: An elongated housing having a seal sleeve; An outer cannula; An outer cannula hub coupled to the proximal end of the outer cannula, the outer cannula hub being partially and slidably disposed within the seal sleeve; An inner cannula partially and slidably disposed within the lumen of the outer cannula; An inner cannula seal disposed between the seal sleeve and the inner cannula; Comprising; The inner cannula seal comprises: An interference ring portion disposed adjacent to the inner surface of the seal sleeve; A beaded ring portion in contact with the outer surface of the inner cannula; A flexible portion extending between the interference ring portion and the beaded ring portion; A biopsy device. (Item 13) The inner cannula seal is configured to maintain a liquid-tight seal between them while allowing longitudinal movement of the inner cannula relative to the seal sleeve. The biopsy device according to item 12. (Item 14) The inner cannula seal has a partial conical shape. The biopsy device according to item 12. (Item 15) The inner cannula seal has a J-shaped cross-section. The biopsy device according to item 12. (Item 16) The proximal end of the outer cannula hub defines an annular groove adjacent to the distal end of the seal sleeve, and the interference ring portion of the inner cannula seal is at least partially disposed within the annular groove. The biopsy device according to item 12. (Item 17) The interference ring portion of the inner cannula seal forms an interference fit within the annular groove. The biopsy device according to item 16. (Item 18) The biopsy device according to item 12, wherein the inner cannula seal further comprises a ring portion with an intermediate bead extending from the outer surface of the flexible portion. (Item 19) The biopsy device according to item 12, wherein the flexible portion of the inner cannula seal is biased to apply a force to the outer surface of the inner cannula against the bead-bearing ring portion to create a liquid-tight seal between the bead-bearing ring portion and the outer surface of the inner cannula. (Item 20) The biopsy device according to item 12, wherein the flexible portion of the inner cannula seal is configured to allow the interference ring portion and the bead-bearing ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the inner cannula and the seal sleeve. (Item 21) The biopsy device according to item 12, wherein the inner cannula seal comprises an ethylene propylene diene monomer (''EPDM'') polymer. (Item 22) The biopsy device according to item 12, wherein the inner cannula seal is manufactured using a molding process. (Item 23) A biopsy device, comprising: an elongated housing having a saline return fitting; an outer cannula partially and slidably disposed within the elongated housing; an inner cannula partially and slidably disposed within each of the lumens of the outer cannula and the saline return fitting; an inner cannula seal disposed between the inner wall of the saline return fitting and the inner cannula; and wherein the inner cannula seal comprises an interference ring portion disposed adjacent to the inner surface of the saline return fitting; a bead-bearing ring portion in contact with the outer surface of the inner cannula; and a flexible portion extending between the interference ring portion and the bead-bearing ring portion. The biopsy device according to item 23, wherein the inner cannula seal is configured to maintain a liquid-tight seal between them while allowing longitudinal movement of the inner cannula relative to the saline return fitting. (Item 24) The biopsy device according to item 23, wherein the inner cannula seal has a partially conical shape. (Item 25) The biopsy device according to item 23, wherein the inner cannula seal has a J-shaped cross section. (Item 26) The biopsy device according to item 23, wherein the inner cannula seal has a J-shaped cross section. (Item 27) The biopsy device according to item 23, further comprising a saline return fitting cap coupled to the distal end of the saline return fitting, wherein the proximal end of the saline return fitting cap defines an annular groove adjacent to the distal end of the saline return fitting, and the interference ring portion of the inner cannula seal is disposed at least partially within the annular groove. (Item 28) The biopsy device according to item 27, wherein the interference ring portion of the inner cannula seal is disposed at least partially within the annular groove. (Item 29) The biopsy device according to item 23, wherein the inner cannula seal further comprises a ring portion with intermediate beads extending from the outer surface of the flexible portion. (Item 30) The biopsy device according to item 23, wherein the flexible portion of the inner cannula seal is biased to apply a force to the outer surface of the inner cannula against the ring portion with beads to create a liquid-tight seal between the ring portion with beads and the outer surface of the inner cannula. (Item 31) The biopsy device according to item 23, wherein the flexible portion of the inner cannula seal is configured to allow the interference ring portion and the ring portion with beads to move longitudinally relative to each other while maintaining a liquid-tight seal between the inner cannula and the saline return fitting. (Item 32) The biopsy device according to item 23, wherein the inner cannula seal comprises an ethylene propylene diene monomer (''EPDM'') polymer. (Item 33) The biopsy device according to item 23, wherein the inner cannula seal is manufactured using a molding process.

Brief Description of the Drawings

[0016] The drawings illustrate the design and utility of embodiments of the disclosed invention, where like elements are referenced by common reference numerals. These drawings are not necessarily drawn to scale. To gain a deeper understanding of the embodiments listed above and the manner in which other advantages and objectives are achieved, a more specific description of the embodiments is provided and illustrated in the accompanying drawings. These drawings depict only typical embodiments of the disclosed invention and are not to be construed as limiting of its scope.

[0017]

Figure 1

[0018]

Figure 2

Figure 3

Figure 4

[0019]

Figure 5

Figure 6

Figure 7

Figure 8

[0020]

Figure 9

Figure 10

Figure 11

Figure 12

DETAILED DESCRIPTION OF THE INVENTION

[0021] For the terms defined below, these definitions shall apply unless different definitions are provided in the claims or otherwise in this specification.

[0022] All numerical values are assumed herein to be modified by the term "about" whether or not explicitly indicated. The term "about" generally refers to a range of numbers that one of ordinary skill in the art would consider equivalent (i.e., having the same function or result) to the recited value. In many instances, the term "about" may include numbers that are rounded to the nearest significant digit.

[0023] The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0024] As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0025] Various embodiments of the disclosed invention are described hereinafter with reference to the figures. Note that the figures are not drawn to scale. Note also that the figures are only intended to facilitate the description of embodiments. They are not intended as an exhaustive description of the invention or as a limitation on the scope of the invention, which is defined only by the appended claims and their equivalents. Additionally, the illustrated embodiments of the disclosed invention need not have all aspects or advantages shown. Aspects or advantages described in conjunction with a particular embodiment of the disclosed invention are not necessarily limited to that embodiment and may be practiced in any other embodiment even if not so illustrated. A more specific description of the embodiments is given and illustrated in the accompanying drawings to better understand the above-listed and other advantages and how they are achieved. These drawings depict only typical embodiments of the disclosed invention and are not to be considered limiting of its scope.

[0026] FIG. 1 depicts a needle set 10 for use with a two-piece biopsy device in a longitudinal cross-sectional view that enables depiction of internal components. The needle set 10 is the “disposable portion” of the two-piece biopsy device. The second part (not shown) of the two-piece biopsy device is the “reusable portion” that includes a drive mechanism for the various components of the needle set 10. The needle set 10 is configured to be discarded after single use, while the reusable portion is configured to be cleaned after each use and used in subsequent biopsies. Thus, the disposable needle set 10 that contacts tissue during the biopsy is discarded after the biopsy, while the reusable portion that can be isolated from the tissue during the biopsy is cleaned and reused. The drive mechanism in the reusable portion is typically more expensive than the components of the needle set 10. Thus, reusing the reusable portion and discarding the needle set 10 reduces the cost of the biopsy. Additional details regarding the exemplary two-piece biopsy device and the reusable portion are described in U.S. Patent No. 10,022,110, which is incorporated herein by reference above.

[0027] The needle set 10 includes a housing 12, an outer cannula 14, an inner cannula 16, a manifold 18, an outer cannula hub 20, an inner cannula hub 22, a seal sleeve 24, and a saline return fitting 26. The outer cannula 14 has a distal tissue piercing tip 28 and a tissue receiving opening (or “opening”) 30 defined adjacent to the distal tissue piercing tip 28 and in the vicinity of its distal end. The inner cannula 16 has an open distal end 32 surrounded by an annular cutting blade. The inner cannula 16 is partially and slidably disposed within the outer cannula 14 such that, as shown in FIG. 1, it can close the tissue receiving opening 30. When the inner cannula 16 slides over the tissue receiving opening 30, the annular cutting blade at its open distal end 32 cuts the tissue that exits through the tissue receiving opening 30 into the lumen of the outer cannula 14. In certain embodiments, an introducer can be attached to the biopsy device. In those embodiments, the receiving opening 30 can include one or more bevels or rounded surfaces to prevent the introducer from catching on the sharp edge of the tissue receiving opening 30 and to facilitate smooth movement of the introducer when it is withdrawn over the tissue receiving opening 30. Various fluids (drugs, anesthetics, saline, and / or air) are introduced into the respective lumens of the outer and inner cannulas 14, 16 (e.g., via the manifold 18 and / or the outer cannula hub 20) to perform a wash of the biopsy site and / or to facilitate the movement of the cut tissue sample out from the saline return fitting 26 through the inner cannula 16 via suction. Additional details regarding an exemplary biopsy method using the needle set 10 are described in U.S. Patent No. 10,022,110, which is incorporated herein by reference in its entirety.

[0028] The outer cannula hub 20 is coupled to the proximal end of the outer cannula 14. The inner cannula hub 22 is coupled to the inner cannula 16 between an intermediate point and its proximal end. The outer and inner cannula hubs 20, 22 are operatively coupled to corresponding components of a reusable portion (not shown), thereby configured to facilitate movement of the outer and inner cannulas 14, 16. The seal sleeve 24 is disposed at the needle set 10 between the outer cannula hub 20 and the inner cannula hub 22, fixing their minimum distance. The seal sleeve 24 is coupled to the outer cannula hub 20 and interferes with the inner cannula hub 22 (using components on the reusable portion of the biopsy device to which the disposable needle set 10 is attached), establishing a lower limit for the distance between the outer cannula hub 20 and the inner cannula hub 22. Thus, the seal sleeve 24 also fixes the minimum distance between the respective distal ends of the outer and inner cannulas 14, 16. The saline return fitting 26 is configured to house the proximal end of the inner cannula 16 and couple to an external vacuum source (not shown) for aspiration of transected tissue from the lumen of the inner cannula 16.

[0029] As described above, the inner cannula 16 is partially, slidably, and coaxially disposed within the lumen of the outer cannula 14. The outer cannula 14 (and the inner cannula 16 disposed therein) is also partially and slidably disposed within the manifold 18 within the housing 12. When the outer cannula 14 slides longitudinally relative to the housing 12, it also slides longitudinally relative to the manifold 18 coupled to the housing 12. Since fluid passes through the manifold 18 into the respective lumens of the outer and inner cannulas 14, 16, the junction between the outer cannula 14 and the manifold 18 must be sealed / liquid-tight to prevent fluid leakage during operation of the needle set 10 including the outer cannula 14 that slides longitudinally relative to the manifold 18. One such fluidically active junction between the outer cannula 14 and the manifold 18 is labeled "D" in FIG. 1 and shown in detail in FIG. 2.

[0030] As shown in FIG. 2, the fluidically active junction D includes an outer cannula seal 100 configured to provide a liquid-tight seal between the outer cannula 14 and the distal end of the manifold 18, while allowing the outer cannula 14 to slide longitudinally relative to the manifold 18 during operation of the needle set 10 and preventing fluid leakage. As shown in FIGS. 5-8, the outer cannula seal 100 includes an interference ring portion 110 on its outer diameter. The interference ring portion 110 is configured to be captured by the distal end of the manifold 18 (as described below) and form an interference fit / seal therewith. The outer cannula seal 100 also includes a beaded ring portion 112 on its inner diameter. The beaded ring portion 112 is configured to form a friction fit / seal with the outer surface of the outer cannula 14 (as described below). The outer cannula seal 100 further includes a flexible portion / bellows feature 114 that couples the interference ring portion 110 to the beaded ring portion 112. The flexible portion 114 is configured to deform (e.g., bend, straighten, and / or stretch) and thereby allow longitudinal movement of the outer cannula 14 relative to the manifold 18 while maintaining a liquid-tight seal between those two components. The outer cannula seal 100, which includes the interference ring portion 110, the beaded ring portion 112, and the flexible portion / bellows feature 114, is integrally formed as a single seal.

[0031] As shown in FIG. 6, the outer cannula seal 100 has a partially conical shape. As shown in FIG. 5, the outer cannula seal 100 (i.e., one of its walls) has a V-shaped cross-section. The outer cannula seal 100 can be manufactured by molding a material such as an ethylene propylene diene monomer (''EPDM'') polymer. In one or more embodiments, the outer cannula seal 100 can be a high compliance seal (e.g., made from 70 Shore A EPDM).

[0032] The distal end of the manifold 18 includes a manifold cap 34 at its distal end. During assembly, the distal end of the manifold 18 and the manifold cap 34 are permanently joined by laser and / or ultrasonic welding of the manifold cap 34 onto the distal end of the manifold 18, and the outer cannula seal 100 can be permanently joined to the distal end of the manifold 18. The distal end of the manifold 18 and the manifold cap 34 together define an annular space 36 adjacent to the distal end of the manifold 18. As shown in FIG. 2, an interference ring portion 110 (see FIG. 5) is disposed within the annular space 36. Due to the relative sizes of the interference ring portion 110 and the annular space 36, the interference ring portion 110 is captured by interference fit within the annular space 36 after the needle set 10 is assembled. In particular, the manifold cap 34 defines an annular edge 38 facing proximally, and the interference ring portion 110 defines an annular stop 36 facing distally. The annular stop 36 facing distally interferes with the annular edge 38 facing proximally and is configured to prevent removal of the interference ring portion 110 from the annular space 36. As shown in FIG. 5, the interference ring portion 110 has a cross-section approximating a parallelogram. The acute angle of the cross-section of the interference ring portion 110 increases interference with the various surfaces of the annular space 36. The interference ring portion 110 is also compressed by the distal end of the manifold 18 and the manifold cap 34 during assembly, strengthening the interference fit between the interference ring portion 110 and the distal end of the manifold 18, which generates a liquid-tight seal between these two components.

[0033] As shown in FIG. 2, the beaded ring portion 112 (see FIG. 5) contacts the outer surface of the outer cannula 14. As shown in FIG. 5, the beaded ring portion 112 has a partially rounded cross-section, which increases the friction between the beaded ring portion 112 and the outer surface of the outer cannula 14. The friction fit between the beaded ring portion 112 and the outer cannula 14 creates a liquid-tight seal between these two components. The flexible portion 114 of the outer cannula seal 100 biases the beaded ring portion 112 against the outer surface of the outer cannula 14 to create a liquid-tight seal between the beaded ring portion 112 and the outer surface of the outer cannula 14.

[0034] The flexible portion / bellows feature 116 is configured to deform (e.g., bend, straighten, and / or stretch) to allow longitudinal movement of the outer cannula 14 relative to the manifold 18 while maintaining a liquid-tight seal between those two components. The material from which the outer cannula seal 100 is formed (e.g., EPDM) facilitates the deformation of the flexible portion / bellows feature 116 associated with the relative movement of the outer cannula 14 and the manifold 18. Thus, the outer cannula 14 can move longitudinally relative to the manifold 18 by a predetermined distance without requiring movement between the beaded ring portion 112 and the outer cannula 14.

[0035] The interference fit between the interference ring portion 110 and the distal end of the manifold 18, the friction fit between the beaded ring portion 112 and the outer cannula 14, and the deformation of the flexible portion / bellows feature 116 are combined to form a liquid-tight seal between the outer cannula 14 and the distal end of the manifold 18. Thus, the outer cannula seal 100 allows longitudinal movement of the outer cannula relative to the manifold while maintaining a liquid-tight seal between the outer cannula and the distal end of the manifold.

[0036] The fluidically active junction between the inner cannula 16 and the seal sleeve 24 is labeled "E" in FIG. 1 and shown in detail in FIG. 3. As shown in FIG. 3, the fluidically active junction E provides a liquid-tight seal between the inner cannula 16 and the seal sleeve 24 and is configured to prevent fluid leakage while allowing the inner cannula 16 to slide longitudinally relative to the seal sleeve 24 during operation of the needle set 10. The inner cannula seal 200 includes an interference ring portion 210 on its outer diameter. The interference ring portion 210 is configured to be captured by the seal sleeve 24 (as described below) and form an interference fit / seal therewith. The inner cannula seal 200 also includes a beaded ring portion 212 on its inner diameter. The beaded ring portion 212 is configured to form a friction fit / seal with the outer surface of the inner cannula 16 (as described below). The outer cannula seal 200 further includes a flexible portion / bellows feature 214 that couples the interference ring portion 210 to the beaded ring portion 212. The flexible portion 214 is configured to deform (e.g., bend, straighten, and / or stretch) to allow longitudinal movement of the inner cannula 16 relative to the seal sleeve 24 while maintaining a liquid-tight seal between those two components. The flexible portion 214 of the inner cannula seal 200 biases the beaded ring portion 212 to apply a force against the outer surface of the inner cannula 16 to create a liquid-tight seal between the beaded ring portion 212 and the outer surface of the inner cannula 16.

[0037] As shown in FIG. 10, the inner cannula seal 200 has a partial conical shape. As shown in FIG. 9, the inner cannula seal 200 (i.e., one of its walls) has a J-shaped cross section. The inner cannula seal 200 also includes an intermediate beaded ring portion 218 that prevents the outer wall of the inner cannula seal 200 from buckling under stress. The inner cannula seal 200 can be manufactured by molding a material such as an EPDM polymer. In one or more embodiments, the inner cannula seal 200 can be a high compliance seal (e.g., made from 70 Shore A EPDM).

[0038] The proximal end of the outer cannula hub 20 is disposed within the open distal end of the seal sleeve 24. The proximal end of the outer cannula hub 20 defines an annular groove 40 adjacent to the distal end of the seal sleeve 24. As shown in FIG. 3, the interference ring portion 210 (see FIG. 9) is disposed within the annular groove 40. Due to the relative sizes of the interference ring portion 210 and the annular groove 40, the interference ring portion 210 is captured by interference fit within the annular groove 40 after the needle set 10 is assembled. In one or more embodiments, the seal sleeve 24 and the outer cannula hub 20 are permanently joined by an adhesive (or alternative means such as laser and / or ultrasonic welding), and the inner cannula seal 200 can be permanently joined to the seal sleeve 24. As shown in FIG. 9, the interference ring portion 210 has a cross section that is close to a "bulbous nose" shape. The bulbous nose shape of the interference ring portion 210 is configured to interfere with various surfaces of the annular groove 40. The interference ring portion 210 is compressed by the seal sleeve 24 and the outer cannula hub 20 during assembly, strengthening the interference fit between the interference ring portion 210 and the seal sleeve 24, which creates a liquid-tight seal between these two components.

[0039] As shown in FIG. 3, the beaded ring portion 212 (see FIG. 9) contacts the outer surface of the inner cannula 16. As shown in FIG. 9, the beaded ring portion 212 has a partially round cross-section, which increases the friction between the beaded ring portion 212 and the outer surface of the inner cannula 16. The friction fit between the beaded ring portion 212 and the inner cannula 16 creates a liquid-tight seal between these two components. The flexible portion 214 of the inner cannula seal 200 is biased to force the beaded ring portion 212 against the outer surface of the inner cannula 16 to create a liquid-tight seal between the beaded ring portion 212 and the outer surface of the inner cannula 16.

[0040] The flexible portion / bellows feature 214 is configured to deform (e.g., bend, straighten, and / or stretch) to allow longitudinal movement of the inner cannula 16 relative to the seal sleeve 24 while maintaining a liquid-tight seal between those two components. The material from which the inner cannula seal 200 is formed (e.g., EPDM) facilitates the deformation of the flexible portion / bellows feature 214 associated with the relative movement of the inner cannula 16 and the seal sleeve 24. Thus, the inner cannula 16 can move longitudinally relative to the seal sleeve 24 by a predetermined distance without requiring movement between the beaded ring portion 112 and the inner cannula 16.

[0041] The interference fit between the interference ring portion 210 and the seal sleeve 24, the friction fit between the beaded ring portion 212 and the inner cannula 16, and the deformation of the flexible portion / bellows feature 214 are combined to form a liquid-tight seal between the inner cannula 16 and the seal sleeve 24. Thus, the inner cannula seal 200 allows longitudinal movement of the inner cannula 16 relative to the seal sleeve 24 while maintaining a liquid-tight seal between the inner cannula 16 and the seal sleeve 24.

[0042] The fluidly active junction between the inner cannula 16 and the saline return fitting 26 is labeled "F" in FIG. 1 and shown in detail in FIG. 4. As shown in FIG. 4, the fluidly active junction F provides a liquid-tight seal between the inner cannula 16 and the saline return fitting 26 and is configured to prevent fluid leakage while allowing the inner cannula 16 to slide longitudinally relative to the saline return fitting 26 during operation of the needle set 10. The inner cannula seal 200' includes an inner cannula seal 200' depicted in FIG. 4, which is the same as the inner cannula seal 200 depicted in FIG. 3 described in detail above. The only difference between the inner cannula seals 200 and 200' is their installation in the needle set 10, as shown in FIG. 1.

[0043] The interference ring portion 210 on the inner cannula seal 200' is configured to be captured by the saline return fitting 26 (as described below) and form an interference fit / seal therewith. The saline return fitting 26 includes a saline return fitting cap 42 at its distal end. The proximal end of the saline return fitting cap 42 defines an annular groove 40' adjacent to the distal end of the saline return fitting 26. As shown in FIG. 4, the interference ring portion 210 (see FIG. 9) is disposed within the annular groove 40'. Due to the relative sizes of the interference ring portion 210 and the annular groove 40', the interference ring portion 210 is captured by interference fit within the annular groove 40' after the needle set 10 is assembled. In one or more embodiments, the saline return fitting 26 and the saline return fitting cap 42 are permanently joined by laser and / or ultrasonic welding, and the inner cannula seal 200 can be permanently joined to the saline return fitting 26.

[0044] Similar to the inner cannula seal 200 depicted in FIG. 3, the interference fit between the interference ring portion 210 and the saline return fitting 26, the friction fit between the beaded ring portion 212 and the inner cannula 16, and the deformation of the flexible portion / bellows feature 214 are combined to form a liquid-tight seal between the inner cannula 16 and the saline return fitting 26. Thus, the inner cannula seal 200' allows longitudinal movement of the inner cannula 16 relative to the saline return fitting 26 while maintaining a liquid-tight seal between the inner cannula 16 and the saline return fitting 26.

[0045] The fluidically active joints described above are configured to eliminate leakage by using highly compliant seals and increased interference with the cannula. Further, these seals reduce the frictional resistance to the outer and / or inner cannula, which can improve the firing speed and reduce the cannula reciprocation force. Although fluidically active joints have been described between various components of the needle set 10, the needle set includes other fluidically active joints (such as between the outer cannula 14 and the proximal end of the manifold 18, as shown at "G" in FIG. 1, for example). Cannula seals similar to the outer and inner cannula seals 100, 200, 200' can be used at these fluidically active joints to generate a liquid-tight seal while allowing relative movement of the various components of the needle set 10. The various dimensions of the cannula seal can also be modified to adjust the cannula seal for use at various locations within the needle set 10.

[0046] Particular embodiments of the disclosed invention have been shown and described, but it should be understood that the above description is provided for illustrative and exemplary purposes only. Accordingly, various changes and modifications can be made without departing from the scope of the disclosed invention. For example, not all of the components depicted and described in the disclosed embodiments are necessary, and various additional embodiments of the disclosed invention may include any suitable combination of the described components, and the general shape and relative sizes of the components may be modified. The systems and methods have been described with reference to a needle set for a biopsy device, but the embodiments can also be configured and utilized using any type of device with a fluidically active junction between components. Further, as will be understood by those skilled in the art, each of the individual variations described and illustrated herein can be readily separated from, or combined with, the features of any of several other embodiments without departing from the scope or spirit of the invention. Thus, the embodiments are intended to illustrate alternatives, modifications, and equivalents that may fall within the scope of the claims.

Claims

1. A biopsy device, wherein the biopsy device comprises: An elongated housing having a manifold; An outer cannula disposed partially and slidably within the manifold; An inner cannula disposed partially and slidably within the lumen of the outer cannula; An outer cannula seal disposed between the manifold and the outer cannula; And comprising: The outer cannula seal is: An interference ring portion in contact with the distal surface of the manifold, wherein the portion of the manifold in contact with the outer cannula seal is the distal surface of the manifold, the interference ring portion; A beaded ring portion in contact with the outer surface of the outer cannula; And a flexible portion extending between the interference ring portion and the beaded ring portion; And comprising: The flexible portion is configured to allow longitudinal movement of the outer cannula relative to the manifold while maintaining a liquid-tight seal therebetween by deforming, a biopsy device.

2. The outer cannula seal has a partially conical shape, the biopsy device according to claim 1.

3. The outer cannula seal has a V-shaped cross-section, the biopsy device according to claim 1.

4. Further comprising a manifold cap coupled to the distal end of the manifold, the manifold cap and the manifold together defining an annular space adjacent to the distal end of the manifold, the interference ring portion of the outer cannula seal being at least partially disposed within the annular space, the biopsy device according to claim 1.

5. The interference ring portion of the outer cannula seal forms an interference fit between the distal surface of the manifold and the inner surface of the manifold cap, the biopsy device according to claim 4.

6. The interference ring portion of the outer cannula seal defines an annular return stop facing distally configured to engage an annular edge facing proximally of the manifold cap, the biopsy device according to claim 4.

7. The flexible portion of the outer cannula seal is biased to apply a force to the beaded ring portion against the outer surface of the outer cannula to create a liquid-tight seal between the beaded ring portion and the outer surface of the outer cannula. The biopsy device according to claim 1.

8. The flexible portion of the outer cannula seal is configured to allow the interference ring portion and the beaded ring portion to move longitudinally relative to each other while maintaining a liquid-tight seal between the outer cannula and the manifold. The biopsy device according to claim 1.

9. The outer cannula seal comprises an ethylene propylene diene monomer ("EPDM") polymer. The biopsy device according to claim 1.

10. The outer cannula seal is manufactured using a molding process. The biopsy device according to claim 1.

Images