Filament cutting device

Abstract

The filament cutting device can include an outer sheath. A bushing can be coupled to a distal end of the outer sheath. An inner diameter of the bushing can be a cutting edge at the distal tip of the bushing. An actuation wire can be slidably extendable within the outer sheath and the bushing. An engager can be coupled to a distal end of the actuation wire. A cavity can be defined along a length of the engager configured to capture a portion of the filament within the cavity. Movement of the actuation wire and the engager with the filament captured within the cavity can cause the cutting edge to cut the filament.

Description

Technical Field

[0001] The present disclosure generally relates to the field of devices and procedures for cutting filaments, and more specifically to methods of using a filament cutting device as part of a tether traction system and procedure to cut the filaments of a tether device.

Background Art

[0002] Access to and cutting of one or more filaments during a medical procedure, such as filaments used as a tether in a tissue incision procedure, can be difficult for medical personnel to perform due to reasons such as remote access to the filament, visualization, serpentine biological structures, establishing sufficient shearing force, and the like.

[0003] Various advantageous medical outcomes can be achieved by embodiments of the present disclosure.

Summary of the Invention

[0004] Various embodiments of a filament cutting device, system, and method are disclosed herein. For example, a method of using a filament cutting device in a system that includes a tether device having a filament that is delivered and disposed within a patient's body lumen to apply a pulling force to tissue during a medical procedure such as endoscopic mucosal resection and / or endoscopic submucosal dissection (EMR / ESD), and that can be retrieved after the procedure by cutting the filament with the filament cutting device is described. Also described herein are exemplary tether devices and / tether delivery devices for use alone and / or in combination with a filament cutting device in the system or other systems.

[0005] In one aspect, the filament cutting device may include an outer sheath. A bushing may be connected to the distal end of the outer sheath. The inner diameter of the bushing may include a cutting edge. The actuating wire may be slidably extendable within the outer sheath and the bushing. An engaging body may be connected to the distal end of the actuating wire. The engaging body may include an outer surface having a diameter that substantially matches the inner diameter of the cutting edge of the bushing. A cavity may be defined along the length of the engaging body configured to capture a portion of the filament within the cavity. Movement of the actuating wire and the engaging body with the filament captured within the cavity may cause the filament to be cut by the cutting edge.

[0006] In various of the described and other aspects, the proximal portion of the cavity may include an angled inclined surface. The distal portion of the cavity may include the innermost curved portion of the cavity that defines a hook shape. The innermost curved portion of the cavity may radially extend within the engaging body a length greater than 50% of the diameter of the engaging body. The cutting edge may be at the distal tip of the bushing. The cutting cavity may be defined along the length of the bushing and the cutting edge may be along the cutting cavity. The outer sheath may comprise coiled windings and the distal tip of the outer sheath may comprise an installation outer surface to which the bushing is connected. The proximal portion of the outer sheath may include an inner diameter smaller than the remaining portion of the outer sheath and the proximal portion of the outer sheath may include an outer diameter smaller than the remaining portion of the outer sheath. The engaging body may include a second cavity substantially opposite the first cavity with respect to the longitudinal axis of the engaging body. The engaging body may include a substantially square outer perimeter that substantially matches the inner perimeter of the bushing.

[0007] In one aspect, the filament cutting device may include an outer sheath. A bushing may be connected to the distal end of the outer sheath. A cavity may be defined along the length of the bushing and may be configured to capture a portion of the filament within the cavity. The actuating wire may be slidably extendable within the outer sheath and the bushing. An engaging body may be connected to the distal end of the actuating wire. The engaging body may include a cutting edge at the distal tip of the engaging body. Movement of the actuating wire and the engaging body with the filament captured within the cavity may cause the filament to be cut by the cutting edge.

[0008] In various described aspects and other aspects, the cutting edge can be the outer diameter of the engaging body. The distal tip of the engaging body can include a surface having an angle extending from the longitudinal axis of the engaging body to the cutting edge. The contact body can be disposed within the distal end of a bushing configured to prevent distal movement of the engaging body. The contact body can include a tapered proximal portion that tapers proximally while decreasing in width. The engaging body can include a tapered distal portion that tapers distally while decreasing in width.

[0009] In one aspect, the filament cutting device can include an outer sheath. The bushing can be connected to the distal end of the outer sheath. The bushing can include a cavity. The cutter can extend across the cavity and can be configured to cut the filament. The cavity can be defined along the length of the bushing and can be configured to capture a portion of the filament within the cavity. The cutter can be a blade having an edge that extends substantially parallel to the longitudinal axis of the filament cutting device. The cavity can be defined laterally across the distal tip of the bushing. The cutter can be an activatable wire configured to melt the filament.

[0010] In one aspect, the filament cutting device can include an outer sheath. The bushing can be connected to the distal end of the outer sheath. The inner diameter of the bushing can be the cutting edge at the distal tip of the bushing. The actuating wire can be slidably extendable within the outer sheath and the bushing. The engaging body can be connected to the distal end of the actuating wire. The engaging body can include an outer surface having a diameter that substantially matches the inner diameter of the cutting edge of the bushing. The cavity can be defined along the length of the engaging body and can be configured to capture a portion of the filament within the cavity. Movement of the actuating wire and the engaging body while capturing the filament within the cavity can cause the filament to be cut at the cutting edge. Since the filament can be disposed at least partially within the cavity of the engaging body, the filament can be cut by the edge of the bushing and / or the cavity in response to proximal movement of the engaging body into the bushing.

[0011] In another aspect, the system may include a filament cutting device, such as the filament cutting device described above and elsewhere in the specification. The system may include a tether device. The system may include a tether delivery device.

[0012] In one aspect, the tether device may include a tether having a distal end, a proximal end, and an elongate body extending therebetween that is made stretchable. The proximal end of the tether may be configured to be attached to a clipping device that is disposed at the distal end of a delivery catheter. The distal end of the tether may be configured to include a loop extending from the neck. The loop may be configured to be engaged by a second clipping device that is disposed at the distal end of the delivery catheter. The loop and the neck may include a filament that may be cut by a filament cutting device, such as the filament cutting device described above and elsewhere in the specification.

[0013] In another aspect, the method may include extending an engaging body of a filament cutting device toward a filament. The filament may be captured within a cavity of the engaging body. The engaging body may cut the filament by being retrieved within an outer sheath.

Brief Description of the Drawings

[0014] Non-limiting embodiments of the present disclosure are described by way of example with reference to the accompanying drawings, which are schematic and are not intended to be drawn to scale. Components that are shown identically or generally identically in the drawings are typically represented by a single number. For clarity, not all components are shown in all of the drawings, and not all components of each embodiment are shown where illustration is not necessarily required for one of ordinary skill in the art to understand the present disclosure. In the drawings,

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DETAILED DESCRIPTION OF THE INVENTION

[0015] The present disclosure is not limited to the specific embodiments specifically described herein. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting beyond the scope of the appended claims. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0016] For use herein, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” are also intended to include the plural forms. The terms “consisting of” and / or “consisting essentially of,” or “comprising” and / or “comprising of” as used herein identify the presence of the stated features, regions, steps, elements, and / or components, but do not preclude the presence or addition of one or more other features, regions, wholes, steps, operations, elements, components and / or groups thereof. As used herein, unless the context clearly indicates otherwise, the conjunction “and” includes each and every one of the structures, components, features, etc. that it conjoins. Also, as used herein, unless the context clearly indicates otherwise, the conjunction “or” includes one or the other of the structures, components, features, etc. that it conjoins, alone and in any combination and number. The term “or” is generally used herein in its sense including “and / or” unless the context clearly indicates otherwise.

[0017] Various embodiments in accordance with embodiments of the present disclosure are described below. As used herein, “proximal end” refers to the end of the device that is closest to the medical practitioner along the device when introducing the device into a patient. “Distal end” refers to the end of the device or object that is furthest from the medical practitioner along the device during implantation, placement, or delivery.

[0018] Herein, it is assumed that all numerical values are modified by the term “about,” whether or not explicitly indicated. The term “about” generally refers to a range of numbers that a person of ordinary skill in the art would consider equivalent (i.e., having the same function or result) to the recited value in the context of the numerical value. In many cases, the term “about” may include numbers that are rounded to the nearest significant digit. Other uses of the term “about” (i.e., in contexts other than numerical values) are assumed to have their ordinary and customary definitions understood from and consistent with the context of the specification, unless otherwise clearly indicated. The recitation of numerical ranges by endpoints includes all numbers within that range including the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, and 5).

[0019] References to "one embodiment", "some embodiments", "other embodiments", etc. in the specification indicate that the described embodiments may include certain features, structures, or characteristics, but not necessarily all embodiments include certain features, structures, and characteristics. Further, such expressions are not necessarily references to the same embodiments. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, whether or not explicitly described, and absent an express contrary statement, it may be within the knowledge of one of ordinary skill in the art to affect the relevant features, structures, or characteristics of other embodiments. That is, the various individual elements described below, even when not explicitly shown in a particular combination, are expected to be combinable or arrangeable with each other to form other additional embodiments or to complement and / or enhance the described embodiments as understood by one of ordinary skill in the art.

[0020] Throughout the present disclosure, embodiments of a filament cutting device, a tether device, and / or a tether delivery device may be specifically described with reference to medical devices and systems and procedures within the digestive system, but such medical devices and methods may be used in connection with tissues such as the abdominal cavity, gastrointestinal system, thoracic cavity, urinary and reproductive tracts. Further, various medical procedures may benefit from the medical devices or procedures including, for example, endoscopic submucosal dissection (ESD), peroral endoscopic myotomy (POEM), cholecystectomy, and video-assisted thoracoscopic surgery (VATS) of the present disclosure. The structure and form, and the method of placement, may find utility beyond the anatomy to stabilize, manipulate, and provide a clear field of view.

[0021] With reference to FIG. 1, an embodiment of a filament cutting device is shown to include an outer sheath 108 for extending into a body lumen of a patient. The filament may be a component that couples together other elements for performing a medical procedure (see FIGS. 19 and 20). Alternatively, the filament may be a suture used for suturing tissue or other closing. After performing a medical procedure, the filament may need to be cut to complete the procedure and remove the component from the patient.

[0022] The distal end of the outer sheath 108 of the device is shown with an engagement body 100 that extends distally out of the outer sheath 108. The engagement body 100 is extendable distally and proximally through the outer sheath 108. The outer sheath 108 can be formed like a coil, for example, to allow for increased flexion movement within a serpentine biological structure. The proximal end of the device includes a handle 140 for manipulating the device and the engagement body 100 associated with the outer sheath 108. The handle 140 is shown with a finger slide 120 for moving the engagement body 100 along the longitudinal axis of the device associated with the outer sheath 108, and a rotary knob 122 for rotating the engagement body 100 about the longitudinal axis.

[0023] Referring to FIG. 2, an embodiment of the actuating element 230 is shown within the inner sheath 232. The actuating element 230 is coupled to the engagement body. Thus, the actuating element 230 and / or the inner sheath 232 can be moved in the proximal or distal direction to operate the engagement body relative to the outer sheath of the device, or can be rotated about the longitudinal axis of the device. The actuating element 230 can be slidable with respect to the inner sheath 232. Alternatively, both the actuating element 230 and the inner sheath 232 can extend axially. The inner sheath 232 and the actuating element 230 can be disposed within the outer sheath of the device. The actuating element 230 can include a material that is more rigid than the material of the inner sheath (such as nitinol, etc.). Thereby, the actuating element 230 can move axially through the inner sheath 232 and / or the device. The inner sheath 232 can include a material that is less rigid than the actuating element 230 (such as PTFE, etc.). Thereby, contact between the more rigid actuating element 230 and the outer sheath is reduced. Since the actuating element 230 moves axially within the inner sheath 232 with substantially no contact with the outer sheath, the frictional force during substantial axial movement of the actuating element 230 and the outer sheath can be reduced. The actuating element 230 and / or the inner sheath 232 can be coated with, for example, silicone, etc. to reduce friction. The actuating element 230 can be, for example, a wire, a rod, etc. The actuating element 230 in any of the embodiments described herein or other embodiments within the scope of the present disclosure, such as an actuating wire, may or may not include the inner sheath 232.

[0024] Referring to FIG. 3A, an embodiment of the filament cutting device is shown to include an outer sheath 308 extending from the proximal end of the device to the distal end of the device. A slidable body 320 (e.g., finger slide) can be moved axially (e.g., in the direction of arrow 327) along the longitudinal axis of the handle 340 at the proximal end of the device by a healthcare provider's hand (e.g., index finger and middle finger) to axially move the actuating wire 310 and the engaging body 300 relative to the outer sheath 308 and the filament 330 to be cut. In some embodiments, the handle 340 converts the axial movement of the outer sheath 308 relative to the actuating wire 310 and the engaging body 300, such that the outer sheath 308 can be retracted and advanced while the actuating wire 310 and the engaging body 300 remain stationary.

[0025] Referring to FIG. 3B, the filament cutting device of FIG. 3A is shown to include a rotatable body 322 in the handle 340 that can be rotated (e.g., in the direction of arrow 325) about the longitudinal axis of the proximal end of the device by a healthcare provider's hand (e.g., thumb and fingers) to rotate the actuating wire 310 and the engaging body 300 relative to the outer sheath 308 and the filament 330 to be cut.

[0026] Referring to FIGS. 3C and 3D, a cross-sectional view of the proximal end of the handle 340 of the filament cutting device of FIGS. 3A and 3B is shown together with the actuating wire 310 extending through the proximal end of the device. The proximal end of the actuating wire 310 is connected to a shaft 321 rotatably coupled to a slidable body 320. Axial movement of the slidable body 320 axially moves the shaft 321 and the actuating wire 310. The actuating wire 310 is connected to a tubular member 323. The tubular member 323 extends through a rotatable member 322, whereby rotation of the rotatable member 322 is converted into rotation of the tubular member 323 and the actuating wire 310. In various embodiments, the tubular member 323 can be a cannula, a hypo tube, etc., and can have a cross-sectional shape that is circular, oval, square, rectangular, a combination thereof, etc. for the conversion of rotation between the rotatable member 322 and the actuating wire 310. The tubular member 323 can extend only inside the proximal end of the filament cutting device (e.g., only extend within the handle 340), or the tubular member 323 can also extend distally along the actuating wire 310 towards the distal end of the filament cutting device. In various embodiments, the actuating wire 310 can include an inner sheath (e.g., the inner sheath 232 of FIG. 2). The inner sheath can also be connected to the shaft 321. In various embodiments, the tubular member can be an inner sheath (e.g., the inner sheath 232 of FIG. 2).

[0027] Referring to FIG. 4A, the proximal portion of the assembled filament cutting device according to an embodiment of the present disclosure is shown to include a handle 440. The handle 440 includes a slidable body 420 for axially operating the device and a rotatable body 420 for rotationally operating the device. The mechanisms for axial and rotational operations can be configured to be exactly the same as or substantially similar to those described above for the embodiments of FIGS. 1-3D. The proximal portion of the outer sheath 408 includes a tension relief tube 409 connected to the outer surface of the outer sheath 408 by a heat shrink tube 411. The tension relief tube 409 can be made of a material such as polypropylene or the like. FIG. 4B reveals the proximal end 409p of the tension relief tube 409 including a flare having an outer diameter and an inner diameter larger than the remaining portion of the tube 409 by showing the unassembled device of FIG. 4A. The proximal end 409p of the tube 409 is connected to the handle 440 by fixing the proximal end 409p to a threaded protrusion 444. The actuating wire 410 passes through the threaded protrusion 444 from the handle 440 and also extends through the outer sheath 408. The flare of the proximal end 409p can be disposed along and / or adjacent to the protrusion 444 along the actuating wire 410 for assembling the device. The tension relief tube 409 is connected to the handle 440 by a cap 442 connecting to the threaded protrusion 444, whereby the flare of the proximal end 409p of the tube 409 is held (e.g., compressed, constrained, etc.) between the cap 442 and the threaded protrusion 444. When melted, the heat shrink tube 411 connects the tension relief tube 409 to the outer sheath, whereby the proximal end 411p of the heat shrink tube adheres to the tension relief tube 409 and the distal end 411d of the heat shrink tube 411 adheres to the outer sheath 408.

[0028] Referring to FIG. 5A, the distal end of an embodiment of the filament cutting device is shown to include an engaging body 500 that can extend distally outward of a bushing 502 connected to the distal end of an outer sheath 508. The engaging body 500 is extendable distally with respect to a filament 530 that is cut by movement of an actuating wire 510 connected to the engaging body 500 relative to the outer sheath 508.

[0029] In various embodiments, the outer diameter of the engagement body may substantially match the inner diameter of the bushing. The bushing may be a cylindrical tube for receiving an engagement member that may be substantially cylindrical. One or both of the engagement body and the bushing may be substantially straight along the longitudinal axis of the engagement body and / or the bushing. The engagement body and / or the bushing may be constructed (e.g., an engagement body wider or thicker than the actuating wire) to be stiffer than the axis of the outer member connected to the actuating wire for the engagement body and / or the bushing. The stiffer structure of the engagement body and / or the bushing may provide strength for cutting filaments that act in combination. On the other hand, the axis of the outer member for the less stiff actuating wire and bushing provides flexibility for moving through a serpentine biological structure and allows it to bend along the passage of the biological structure. The relative stiffness and width of the engagement body compared to the bushing also improves the extrudability of the engagement body through the outer member. A smooth fluid or coating may be applied to one or both of the bushing and / or the engagement body so that they are slidable relative to each other. In various embodiments, the engagement body or the bushing may include stainless steel, 304 stainless steel, nitinol, polymer, etc.

[0030] Referring to FIG. 5B, the assembly 500 of FIG. 5A is moved proximally relative to the bushing 502 and the filament 530. The filament 530 is captured within a substantially radial cavity 512 of the assembly 500. The filament 530 is captured by the proximal movement of the assembly 500 with the filament 530 sliding along the outer surface of the assembly 500. The filament 530 may slide along an inclined surface 503 having a gradient of a proximal portion of the assembly 500 that defines the outer periphery of the cavity 512. The inclined surface 503 with a gradient may be an introduction portion for the filament 503 until it contacts the innermost curved portion of the cavity 512 that defines the hook portion 505. Since the hook portion 505 is formed, when the assembly 500 is aligned with the bushing 502, the filament 530 crosses the bushing 502 so as to be substantially orthogonal to the bushing 502. For example, the innermost curved portion of the cavity 512 may be defined with respect to two sides of the assembly 500. Each side may be arranged in relation to each other such that the filament 530 may be orthogonal to the assembly 500 and / or the bushing 520. That is, one side of the filament may not be arranged at a different angle from the other side of the filament that crosses the assembly 500 and the bushing 502 with respect to the assembly 500 or the bushing 502. The filament 530 may be prevented from moving distally beyond the cavity 512 by contact with the distal portion 501 of the assembly 500 that extends proximally at the outer periphery of the cavity 512. The cavity 512 is shown as an opening including the lumen of the assembly 500, but in various embodiments the assembly 500 is solid and the radial cavity 512 may instead be defined by a solid assembly 400 (such as shown in FIGS. 10A - 10D). In various embodiments, the inclined surface 503 with a gradient may be uniform with the rest of the outer periphery of the cavity 512, or may be wider at the surface 503 and uniform along the rest of the outer periphery of the cavity 512, or may be wider at the inclined surface 503 with a gradient and tapered along the outer periphery of the cavity 512. The wider surface 503 and / or the tapered outer periphery of the cavity 512 may help capture and arrange the filament 530 within the cavity 512.

[0031] Referring to FIG. 5C, the assembly 500 of FIGS. 5A and 5B can be moved proximally relative to the outer sheath 508 and into the bushing 502 of the outer sheath 508 with the filament 530 captured within the cavity 512. The bushing 502 includes a lumen defined at the distal end of the bushing 502 by a substantially sharp edge 504 (e.g., as compared to the blunt outer edge or surface at the distal end of the bushing 502). The assembly 500 is substantially linear along the longitudinal axis of the assembly 500 and is aligned with the bushing 502. The outer diameter of the assembly 500 substantially matches the inner diameter of the bushing 502 at the edge 504, i.e., a sliding fit is possible. Thus, when the filament 530 is moved proximally by the cavity 512 of the assembly 500 to the edge 504, the shearing force between the edge 504 and the outer surface of the assembly 500 or the edge defining the distal portion of the cavity 512 cuts the filament 530. In various embodiments, the edge defining the cavity 512 (e.g., the hook portion 505 of the cavity) may be substantially sharp and / or the edge 504 of the bushing 502 may be substantially sharp. In various embodiments, the bushing 502 and the outer sheath 508 can be moved distally relative to the assembly 500 and the filament 530.

[0032] Referring to FIG. 5D, the assembly 500 of FIGS. 5A-5C can be moved further proximally inside the bushing 502 and the outer sheath 508. Thus, the cut portion of the filament 530 (not shown) is captured for removal within the bushing 502 and / or the outer sheath 508. Since the filament 530 can be cut at one location by the bushing 502 and / or the cavity 512, it is also understood that additional portions of the filament 530 are not captured within the bushing 502 and / or the outer sheath 508. The device can be removed with the cut filament 530 left temporarily (e.g., a retrieval device or other end effector can protect and remove the cut filament 530) or permanently within the patient.

[0033] With respect to FIG. 6, a side view (and accompanying detailed view) of cavity 612 of an embodiment of engagement body 600 is shown. Engagement body 600 includes an outer diameter that tapers in a proximal direction along engagement body 600 toward a proximal portion of engagement body 600 that may be connected to an actuating wire. The diameter may gradually taper to guide engagement body 600 relative to a bushing and / or outer sheath without the need to be precisely aligned (e.g., axially along the longitudinal axis of one or both of engagement body 600 and the bushing). In some embodiments, engagement body 600 may have a constant diameter along its length. Cavity 612 may have a depth 622 from the outer surface of engagement body 600 that is greater than 50% of outer diameter 620 of engagement body 600. In various embodiments, depth 622 may have a length that is about 50% of outer diameter 620. The outer profile of cavity 612 may have a number of shapes including a hook-like shape that may assist in holding a filament when contacting the surface at the innermost portion of cavity 612. A typical size of the outer profile of cavity 612 may include, for example, that the inclined surface of the introduction portion of the proximal portion of cavity 612 is at an angle of about 30 degrees from the outer surface of engagement body 600. The inclined surface of the outlet portion distal to the angled proximal surface of cavity 612 may include an angle of about 50 degrees from the outer surface of engagement body 600. The angles herein can be varied and selected as desired based on a given application such that, for example, the angled proximal surface of cavity 612 with an introduction angle and / or the angled surface with an outlet angle can be from about 0 degrees to about 90 degrees from the outer surface of engagement body 600. Other sizes are contemplated and will be recognized as being within the scope of the present disclosure.

[0034] In various embodiments, the engagement body and / or bushing may include a cavity as described herein. The filament may be captured by axial movement of one or both of the engagement body and the bushing. The filament may slide along the outer surface of the engagement body and / or bushing. The filament may slide along an inclined surface having a gradient at a proximal or distal portion of the engagement body or bushing that defines the outer perimeter of the cavity. The filament may be prevented from moving out of and / or beyond the cavity by contacting the outer perimeter of the cavity that extends in a direction back to an opposing end of the cavity (e.g., forming a hook-like shape).

[0035] With reference to FIG. 7, a cross-sectional view of an embodiment of the bushing is shown to include a lumen 704 therethrough. The lumen 704 has a proximal portion 704p having a larger diameter than the distal portion 704d. Thus, the proximal portion 704p of the lumen 704 can be disposed around the distal end of the outer sheath. The distal portion 704d of the lumen 704 has a diameter 706 that can substantially match the outer diameter of the engaging body. Thus, the inner edge 708 inside the distal end of the bushing can generate sufficient shearing force with the engaging body to cut the filament. The bushing can be fixedly coupled to the distal end of the outer sheath, for example, by welding, soldering, waxing, adhesives, bonding, mechanical fasteners, etc. In some embodiments, the outer sheath and the bushing can be integrally formed. And in other embodiments, the outer sheath and the bushing can be coupled.

[0036] Referring to FIG. 8, an embodiment of the outer sheath 808 is shown with a coil body (accompanied by cross-sectional views along lines A-A and B-B respectively). The coil body can be formed to have a variable outer diameter on one or more mandrels. The outer sheath 808 having the coil body can allow for greater radial flexibility and axial stiffness than an outer sheath with a solid, uniform wall. The proximal portion 808p of the outer sheath 808 has an inner diameter and an outer diameter that are smaller than those of the remainder of the outer sheath 808. This can help maintain a lower profile and maneuverability compared to the rest of the device. The proximal portion 808p of the outer sheath 808 extends distally towards the tapered portion 808t of the outer sheath 808. The tapered portion 808t includes an outer diameter that increases distally and an inner diameter that increases distally. The tapered portion 808t extends towards the distal portion 808d of the outer sheath 808, which is shown with a substantially uniform outer diameter. The distal portion 808d of the outer sheath 808 can be processed by grinding (e.g., longitudinal grinding, polishing, etc.) to form a substantially uniform outer diameter. The diameter of the distal portion 808d of the outer sheath 808 substantially matches within the inner diameter of the working channel of the endoscope (e.g., about 2.8 mm, etc.), i.e., it can be slip-fitted. The distal tip 809 of the outer sheath 808 extending from the distal portion 808d can be ground more than the distal portion 808d is ground, as shown in FIG. 8 for example. Thus, the outer diameter of the distal tip 809 is smaller than the outer diameter of the distal portion 808d. The outer diameter of the distal tip 809 can substantially match the inner diameter of the proximal portion of the lumen of the bushing. Thus, the bushing can be disposed over and attachable to the distal tip 809, and thus, the outer diameter of the bushing can substantially match the outer diameter of the distal portion 808d of the outer sheath 808. The inner diameter of the distal tip 809 can match the inner diameter of the distal portion 808d of the outer sheath 808 and the inner diameter of the distal portion of the bushing. Thus, the engagement body can move slidably within the distal portion 808d and the distal tip 809 of the outer sheath 808 and through the bushing. In various embodiments, the outer sheath 808 has a substantially uniform outer diameter along its length.

[0037] With respect to FIG. 9, the engagement body 900 is shown to include a surface of the lateral distal tip 900t that transitions to an inclined surface 901 extending proximally at an angle along the longitudinal axis of the engagement body 900. The inclined surface 901 is substantially distal to the cavity 912 of the engagement body 900 along the length of the engagement body 900. The cavity 912 is shown as being formed within or defined by the solid body of the engagement body 900. However, the cavity 912 may include a substantially radial opening formed within the engagement body 900. The inclined surface 901 transitions proximally to the outer peripheral surface 903 of the engagement body 900 and continues to extend into the cavity 912. The inclined surface 901 may assist in capturing a filament within the cavity 912 of the engagement body, as shown and described with respect to the inclined surfaces of FIGS. 10A - 10D. The transitions between the inclined surface 901 and the outer peripheral surface 903, and between the outer peripheral surface 903 and the cavity 912 may each include a fillet 902 (e.g., a circular surface, a smooth surface, a non-traumatic surface, etc.). The fillet 902 may reduce friction with other parts of the device, another device, and / or the patient's biological structure as compared to an edge without a fillet. Axial observation of the orientation of the engagement body 900, parts of the engagement body 900, and / or the engagement body 900 or cavity 912 during a procedure may be difficult for a healthcare provider to identify. The fillet 902 may provide a surface (e.g., reflecting light at an angle different from other surfaces of the engagement body 900 or reflecting light in a different shape) that is distinguishable by a healthcare provider as compared to other surfaces of the engagement body 900.

[0038] Referring to FIGS. 10A - 10D, the distal end of the embodiment of the filament cutting device is shown to be substantially similar to that described with respect to FIGS. 5A - 5D. In FIGS. 10A - 10D, the distal portion of the engaging body 1000 includes an inclined surface 1001. The inclined surface 1001 can slide along the filament 1030, for example, when the actuating wire 1010 and the engaging body 1000 are moved distally into contact with the filament 1030. While the engaging body 1000 moves distally into contact with the filament 1030, the filament 1030 can slide proximally along the inclined surface 1001 toward the cavity 1012 of the engaging body 1000. The contact of the distal tip of the engaging body 1000 including the inclined surface 1001 with the filament 1030 can facilitate the capture of the filament 1030 within the cavity 1012 as compared to a distal tip of the engaging body 1000 having a substantially lateral surface that collides with the filament 1030 and guides the filament 1030 away from the cavity 1012. The engaging body 1000 can have a fillet surface along the outside of the engaging body from the distal tip to the cavity 1012 to assist in preventing the filament 1030 from being damaged or cut prematurely. The filament 1030 can be captured within the cavity 1012 and stored proximally for cutting within the bushing 1002 of the outer sheath 1008 by the proximal movement of the engaging body 1000 relative to the outer sheath 1008. When the engaging body 1000 is received within the outer sheath 1008, the engaging body 1000 can remain fixed after capturing the filament 1030, and the bushing 1002 and the outer sheath 1008 can extend distally to cut the filament 1030. The engaging body 1000 can be moved distally relative to the bushing 1002 to remove the cut portion 1031 of the filament 1030.

[0039] In various embodiments, the filament can be cut in various ways. For example, the filament can be cut by a cutter such as mechanical, electrical, chemical, etc., by plastic fracture, or by tensile fracture. In various embodiments, the filament of the device can be cut during or at the end of a medical procedure. The cutting of the filament can be performed for various reasons, including, for example, release of the device, removal of the filament such as a suture, release of tension between devices, between the device and a biological structure, between biological structures, and between a first part and a second part of a biological structure.

[0040] Referring to FIGS. 11A and 11B, embodiments of the engagement body 1100 and the bushing 1102 are shown. As described herein, the engagement body 1100 can be coupled to the actuating wire, and the bushing 1102 can be coupled to the outer sheath. The engagement body 1100 is slidable within the lumen 1104 of the bushing 1102. The engagement body 1100 has a non-circular outer periphery (e.g., square, rectangular, polygonal, etc.) that substantially conforms to the non-circular lumen 1104. The cavity 1112 of the engagement body 1100 can be used to capture the filament 1130 for the purpose of cutting the filament 1130 between the cavity 1112 and the bushing 1102 by movement of the engagement body 1100 relative to the bushing 1102 and / or movement of the bushing 1102 relative to the engagement body 1100. As shown, in the embodiment, neither the outer periphery nor the cavity 1112 of the engagement body 1100 includes any curved surfaces. In some embodiments, the non-circular outer periphery shape of the engagement body 1100 can be advantageous in that it can utilize less input, less time, and / or less tolerance control for manufacturing than others.

[0041] Referring to FIG. 12, an embodiment of the engagement body 1200 is shown to include a first cavity 1212 and a second cavity 1213. Cavities 1212, 1213 are oriented substantially opposite to each other with respect to the longitudinal axis l of the engagement body 1200. The second cavity 1213 enables capturing a filament at another portion of the engagement body 1200. The substantially opposite orientation of the cavities 1212, 1213 allows for a minimal rotation of the engagement body 1200 to capture the filament (i.e., less rotation around the longitudinal axis l of the engagement body 1200 may be required compared to more rotation that may be required in an embodiment having only the first cavity 1212 to bring the cavities 1212, 1213 into contact with the filament). Both cavities 1212 and 1213 are arranged to have a depth that extends through the longitudinal axis l (i.e., exceeding 50% of the outer diameter of the engagement body 1200). However, in various embodiments, the cavities may extend to the longitudinal axis l or may not reach radially. For example, the proximal angles of the introductions of the cavities 1212, 1213 to the outer surface of the engagement body 1200 are smaller, so the cavities 1212, 1213 do not extend radially beyond the longitudinal axis l. Cavities 1212, 1213 overlap each other along the longitudinal axis l and also overlap transversely and radially through the longitudinal axis l. However, cavities 1212, 1213 may be arranged such that they do not overlap each other along the longitudinal axis l and do not overlap transversely and radially through the longitudinal axis l. And / or, cavities 1212, 1213 may not be oriented substantially opposite to each other with respect to the longitudinal axis l. Although two cavities 1212, 1213 are shown, any number of cavities, such as 0, 1, 3, 4, 5, 8, 10, 20, etc., may be employed. Cavities 1212, 1213 are shown to be arranged at approximately 180 degrees with respect to the longitudinal axis l, but any angular arrangement, such as approximately 60 degrees, approximately 90 degrees, approximately 120 degrees, approximately 150 degrees, etc., may be employed.

[0042] Referring to FIG. 13A, an embodiment of the engagement body 130 and the bushing 1302 is shown. As described herein, the engagement body 1300 can be connected to an actuating wire, and the bushing 1302 can be connected to an outer sheath. The engagement body 1300 is slidable within the lumen 1304 of the bushing 1302. The engagement body 1300 includes a substantially radial first cavity 1312 and an angled ramp 1303 of the proximal portion of the engagement body 1300 that defines the outer periphery of the first cavity 1312. The angled ramp 1303 of the first cavity 1312 extends to the innermost curved portion of the first cavity 1312 that defines a hook portion at the second surface 1305 of the first cavity 1312. The first cavity 1312 is shown as an opening that includes the lumen of the engagement body 1300, but in various embodiments the engagement body 1300 may be solid and the cavity 1312 may alternatively be defined by a solid engagement body 1300 (e.g., as shown in FIGS. 10A - 10D). The bushing 1302 includes a substantially radial second cavity 1313 that extends into the lumen 1304. The second cavity 1313 includes a proximal surface 1314 and a distal surface 1315 that converge at the curved central portion 1316 of the second cavity 1313. The proximal surface 1314 and the distal surface 1315 are angled such that the outer portions of the surfaces 1314, 1315 are further apart from each other compared to the inner portions of the surfaces 1314, 1315 (i.e., towards the central portion 1316). This orientation of the proximal and distal surfaces 1314, 1315 of the second cavity 1313 forms the outer periphery of the second cavity 1313. Thus, the second cavity 1313 has a wider outer portion at the outer surface of the engagement body 1300 and a narrower inner portion at the curved central portion 1316.

[0043] Referring to FIG. 13B, the first and second cavities 1312, 1313 of FIG. 13A can be substantially aligned to receive and capture the filament 1330. Since the bushing 1302 can extend in the distal direction, the filament 1330 enters the widest outer portion of the second cavity 1313. The filament 1330 can be moved into the second cavity 1313 along the angled outer periphery of the second cavity 1313. The second cavity can guide the filament 1330 in the proximal direction toward the narrowest inner portion of the second cavity 1313. When the cavities 1312, 1313 are aligned, the filament 1330 is proximal to the distal surface of the first cavity 1312 (i.e., the distal surface 1315 of FIG. 13A) within the inner portion of the second cavity 1313.

[0044] Referring to FIG. 13C, with the filament 1330 captured within the first and second cavities 1312, 1313 of FIGS. 13A and 13B, the engagement body 1300 can be moved in the proximal direction relative to the bushing 1302. Since the first and second cavities 1312, 1313 move past each other, the filament 1330 is subjected to a shearing force between the outer edge 1316 of the distal outer periphery of the first cavity 1312 and the proximal inner edge of the outer periphery of the second cavity 1313.

[0045] Referring to FIG. 13D, since the first and second cavities 1312, 1313 of FIGS. 13A - 13C cross the filament 1330 and move past each other, the filament 1330 is cut. The cut portion 1331 of the filament 1330 can remain within the lumen 1304, be pulled proximally through the lumen 1304, be pushed distally through the lumen 1304, or be pushed substantially radially outwardly toward the outside of the second cavity 1313.

[0046] Referring to various embodiments, the cavity and / or bushing of the engagement body can include various shapes, surfaces and / or edges for the engagement, reception, capture, movement, sliding, stopping, guiding, shearing and / or retention of filaments or portions of filaments. Combinations of various portions of the cavity shapes and / or surfaces shown and described with respect to a particular embodiment or embodiments can be used across other embodiments of the disclosed cavity or other cavities within the scope of the present disclosure.

[0047] Referring to FIG. 14, an embodiment of an engagement body 1400 and a bushing 1402 is shown. As described herein, the engagement body 1400 can be connected to an operating wire and the bushing 1402 can be connected to an outer sheath. The engagement body 1400 is slidable within the lumen 1404 of the bushing 1402. The bushing 1402 includes a substantially radial cavity 1412 that extends into the lumen 1404. The cavity 1412 includes a proximal surface 1414 and a distal surface 1415 that converge at a curved central portion 1416 of the cavity 1412. The engagement body 1400 includes a cutting edge 1401 at the distal tip of the engagement body 1400 at the outer diameter of the engagement body 1400. The distal tip of the engagement body 1400 includes a surface 1403 having an angle that extends from the longitudinal axis l of the engagement body 1400 towards the cutting edge 1401. The surface 1403 extends in both the proximal direction and the inward direction from the cutting edge 1401 towards the longitudinal axis l. A filament can be captured within the cavity 1412 and the engagement body 1400 can be moved within the lumen 1404 towards the filament within the cavity 1412. A contact body 1408 is disposed within the distal end 1402d of the bushing 1402 that prevents the distal movement of the engagement body 1400. To ensure complete cutting of the filament, the contact body 1408 can include a material that is soft enough such that the cutting edge 1401 can extend distally beyond the filament into the contact body 1408 at least partially. For example, the contact body 1408 can include urethane, high density polyethylene, plasticized PVC, etc. The bushing 1402 includes a non-traumatic tip 1402t having a diameter that narrows distally so that a biological structure or other device is not damaged during delivery of the device and / or a narrow passage can be traversed more easily compared to a device without the non-traumatic tip 1402t.

[0048] Referring to FIG. 15, an embodiment of the engagement body 1500 and the bushing 1502 is shown. As described herein, the engagement body 1500 can be connected to the actuating wire, and the bushing 1502 can be connected to the outer sheath. The engagement body 1500 is slidable within the lumen 1504 of the bushing 1502. The bushing 1502 includes a substantially radial cavity 1512 that extends into the lumen 1504. The cavity 1512 includes a proximal surface 1514 and a distal surface 1515 that converge at the curved central portion 1516 of the cavity 1512. The engagement body 1500 includes a cutting portion 1501 at the distal tip of the engagement body 1500, which can be a blade tip or a blunt surface. The cutting portion 1501 is the distal portion of the engagement body 1500 that gradually tapers distally while decreasing in width. The filament can be captured within the cavity 1512, and the engagement body 1500 can be moved within the lumen 1504 toward the filament within the cavity 1512. The contact body 1508 is disposed within the distal end 1502d of the bushing 1502 that prevents the distal movement of the engagement body 1500. The contact body 1508 includes a tapered proximal portion 1509 that gradually tapers proximally while decreasing in width. With the filament captured within the cavity 1512, the engagement body 1500 can be moved distally toward the contact body 1508. Thereby, the filament is compressed and / or sheared between the cutting portion 1501 and the proximal portion 1509. Thereby, the filament is cut.

[0049] Referring to FIGS. 16A - 16C, an embodiment of the engagement body 1600 and the bushing 1602 is shown. As described herein, the engagement body 1600 is coupled to the actuating wire and the bushing 1602 is coupled to the outer sheath. The engagement body 1600 is slidable within the lumen 1604 of the bushing 1602. The bushing 1602 includes a substantially radial cavity 1612 that extends into the lumen 1604. The cavity 1612 includes a proximal surface 1614 and a distal surface 1615 that converge at the curved central portion 1616 of the cavity 1612. The engagement body 1600 includes a cutting edge 1601 at the distal tip of the engagement body 1600 at the outer diameter of the engagement body 1600. The distal tip of the engagement body 1600 includes a surface 1603 having an angle that extends across the longitudinal axis l of the engagement body 1600 toward the cutting edge 1601. The inclined surface 1603 is used to capture the filament and the cutting edge 1601 around the inclined surface 1603 can reduce the amount of shear stress required to cut the filament as compared to a radial cross-section having a shorter outer perimeter around the surface. The filament 1630 can be captured within the cavity 1612 and the engagement body 1600 can be moved within the lumen 1604 toward the filament 1630 within the cavity 1612. Since the cutting edge 1601 is moved distally beyond the cavity 1612, the cutting edge 1601 and the inner edge of the distal surface 1615 shear the filament 1630.

[0050] Referring to FIG. 17, an embodiment of a filament cutting device is shown to include a bushing 1702 coupled to the distal end of an outer sheath 1708. The bushing 1702 includes a substantially radial cavity 1712. The cavity 1712 includes a proximal surface 1714 and a distal surface 1715 that converge at a curved central portion 1716 of the cavity 1712. A cutter 1701 extends across the cavity 1712. The cutter 1701 extends substantially parallel to the longitudinal axis of the bushing 1702, but may be angled parallel or perpendicular to, for example, the proximal surface 1714. The cutter 1701 includes an edge that is oriented substantially radially outward from the cavity 1712. The filament 1730 can be trapped within the cavity 1712 and the bushing 1702 can be moved in a proximal direction and / or a radial direction relative to the filament 1730 such that the cutter 1701 cuts the filament 1730. The distance between the outer surface of the bushing 1702 and the edge of the cutter within the cavity 1712 is substantially equal to the diameter of the filament 1730, such as about 0.25 mm. Thus, the distal surface 1715 can be positioned adjacent to the filament 1730 to act as a backstop against the filament 1730 for manipulation of the filament 1730 and / or for cutting. Since the embodiment of FIG. 17 has no moving parts relative to each other, the pressure applied to the outer sheath 1708 and / or the filament 1730 during operation can be reduced.

[0051] Referring to FIG. 18, an embodiment of a filament cutting device is shown to include a bushing 1802 coupled to the distal end of an outer sheath 1808. The bushing 1802 includes a cavity 1812. The cavity 1812 extends substantially laterally across the distal tip 1802t of the bushing 1802 and includes a curved central portion 1816 of the cavity 1812. A cutter 1801 extends across the cavity 1812. The cutter 1801 extends across the longitudinal axis of the bushing 1812, although it may be angled. The cutter 1801 is an operable wire configured to melt the filament. The ends 1814, 1815 of the cutter 1801 extend into the bushing 1802 and are coupled (e.g., welded) to a first lead wire 1851 and a second lead wire 1852 that extend proximally along the bushing 1802 and the outer sheath 1808 towards an energy source (e.g., a battery within a handle). The cutter 1801 and the leads 1851, 1852 may be externally coated within the bushing 1802. The cutter 1801 has a conductive outer surface, while the leads 1851, 1852 are insulated by an insulating coating along the bushing 1802 and / or the leads 1851, 1852. Since the embodiment of FIG. 18 has no moving parts, it may reduce the pressure on the outer sheath 1808 and / or the filament during operation. The cutter 1801 may include various conductive materials such as nichrome, an iron-chromium-aluminum alloy, and the like.

[0052] Referring to FIG. 19, an embodiment of a tether device 1900 is shown to include an elastic extensible body 1904 having a first end 1901 and a second end 1902. A long tubular hollow body alignment member 1908 is extendable at least partially over the elastic body 1904. The alignment member 1908 can align and / or orient the device 1900 within the working channel of an endoscope, another introducer sheath, or a catheter during operation of the device 1900. A clip 1910 is coupled to the first end 1901 of the elastic body 1904. A neck 1912 extends from the second end 1902 of the elastic body 1904 to a loop 1914. Since the clip 1910 can be manipulated by a healthcare provider, the clip 1010 coupled to the first end 1901 of the tether device 1900 is delivered toward the tissue. The clip 1910 can be coupled to the tissue in addition to being coupled to the first end 1901 of the elastic body 1904. The loop 1914 can be engaged by another device such as an additional clip. The additional clip can be moved to place the loop 1914 within the jaws of the additional clip and to couple the additional clip to another living structure or another portion of tissue. Thus, the second end 1902 of the elastic body 1904 extends away from the first end 1901. In this position, the tether device 1900 is subjected to a greater axial tension as compared to the relaxed state of the tether device 1900 shown in FIG. 19.

[0053] In various embodiments, the clip 1910 can be rotatable to rotate the tether device 1900. The clip 1910 can be repositionable before, during, and / or after the procedure. The clip 1910 can be a disposable clip. A medical procedure, such as tissue resection, is performed with tension applied to the tether device 1900 and the tissue coupled to the tether device 1900. During or after the procedure, the tension can be released by cutting filaments of the tether device, such as the elastomer 1904, the alignment member 1908, the neck 1912, and / or the loop 1914 (see, e.g., FIGS. 5A-5D and 10A-10D). In various embodiments, the elastomer 1904 can be cuttable by a cutting device. In various embodiments, the elastomer 1904 can include one or more protectors at one or more ends 1901, 1902 of the elastomer 1904, each of which can be coupled to a filament. The elastomer 1904 can include an internal filament that can prevent the elastomer 1904 from stretching beyond a desired length. The filaments of the elastomer 1904 can include one or more loops (e.g., loop 1914 with or without neck 1912) that can be of various shapes and diameters, extend to, or be coupled to, the loop.

[0054] Referring to FIG. 20, an embodiment of a tethering device is shown as being delivered and applying tension between a target tissue 2004 and another tissue 2038. An elastomer 2014 is coupled to a first clip 2012 at a first end of the elastomer 2014. The first clip 2012 is coupled to the target tissue 2004 for excision. A second end of the elastomer 2014 is coupled to a second clip 2011. The second clip 2011 is coupled to the tissue 2038, such that the elastomer 2014 is under tension. An excising tool 2020 is delivered toward the target tissue 2004 via an endoscope 2006. When the target tissue 2004 is excised, the elastomer 2014 pulls the first clip 2012 and the target tissue 2004 substantially toward the second clip 2011. Thereby, visualization between the endoscope 2006, the excising tool 2020, and the target tissue 2004 is maintained. During or at the end of the procedure, an embodiment of a filament cutting device may be delivered to the elastomer 2014 to release the tension applied to the elastomer 2014 by cutting the elastomer 2014. Various embodiments of the tethering device and clip delivery device, or other delivery devices for the tethering device such as the tethering device and clip delivery device of FIG. 19, may be used in a tissue incision procedure such as the procedure shown in FIG. 20.

[0055] An embodiment of a method of filament cutting includes inserting a device having an outer sheath into a patient. An engaging body and / or a bushing of the device may be manipulated toward the filament. The filament may be captured within one or more cavities of the device. The engaging body and / or the bushing may be moved axially along the device to cut the filament.

[0056] All of the apparatus and / or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. Although the apparatus and methods of the present disclosure have been described with reference to preferred embodiments, it may be apparent to those skilled in the art that changes may be applied to the apparatus and / or methods, and the steps or series of steps of the methods, described herein without departing from the concept, spirit, and scope of the present disclosure. All such similar substitutes and modifications that are apparent to those skilled in the art are considered to be within the spirit, scope, and concept of the present disclosure as defined by the appended claims.

Claims

Claim 1. A filament cutting device, comprising: an outer sheath; an engaging body having a predetermined length and extending linearly along a longitudinal axis, the engaging body including a first radially extending cavity positioned along the length of the engaging body and configured to capture a portion of a filament therein; a bushing connected to the distal end of the outer sheath and having a predetermined length, the bushing defining a second radially extending cavity that extends radially inwardly through the wall of the bushing and is configured to capture the portion of the filament; an operating wire slidably and extendably disposed within the outer sheath and the bushing; the engaging body being connected to the distal end of the operating wire; at least one of an outer diameter of the first radially extending cavity and an inner diameter of the second radially extending cavity includes an edge; the filament cutting device being configured to capture a portion of the filament oriented to extend laterally across the first radially extending cavity and the second radially extending cavity; the filament being severed by at least one edge of the first and second radially extending cavities as a result of relative axial movement of the bushing and the engaging body with the filament captured within the first radially extending cavity and the second radially extending cavity. Claim 2. The filament cutting device according to claim 1, wherein a proximal portion of the first radially extending cavity includes an angled ramp surface and a distal portion of the first radially extending cavity includes a deepest curved portion of the first radially extending cavity defining a hook shape. Claim 3. The filament cutting device according to claim 2, wherein the deepest curved portion of the first radially extending cavity extends radially with respect to the longitudinal axis of the engaging body within the engaging body over a depth of the first radially extending cavity greater than 50% of a diameter of the engaging body. Claim 4. The filament cutting device according to any one of claims 1 to 3, wherein the first radially extending cavity and the second radially extending cavity each further include an edge. Claim 5. The filament cutting device according to any one of claims 1 to 4, wherein the outer sheath includes a wound coil and a distal tip of the outer sheath includes a ground outer surface connecting the bushing to the outer sheath. Claim 6. The proximal portion of the outer sheath has an inner diameter smaller than that of the remaining portion of the outer sheath, and the proximal portion of the outer sheath has an outer diameter smaller than that of the remaining portion of the outer sheath. The filament cutting device according to any one of claims 1 to 5.

7. The engaging body further includes a third radial cavity substantially opposite to the first radial cavity around the longitudinal axis of the engaging body. The filament cutting device according to any one of claims 1 to 6.

8. The engaging body includes a substantially rectangular outer periphery that substantially matches the inner periphery of the bushing. The filament cutting device according to any one of claims 1 to 7.

9. A filament cutting device, An outer sheath, A bushing connected to the distal end of the outer sheath and having a predetermined length, the bushing being positioned along the length of the bushing and configured to capture a portion of the filament inside, the bushing including a radial cavity extending radially inward through the wall of the bushing, An operating wire slidably extendable within the outer sheath and the bushing, An engaging body connected to the distal end of the operating wire and having a predetermined length and extending linearly along its longitudinal axis, the engaging body having a cutting edge positioned along the length of the engaging body, The filament cutting device is configured to capture a portion of the filament oriented to extend laterally across the radial cavity, A filament cutting device that cuts the filament with the cutting edge by the movement of the operating wire and the engaging body with the filament captured within the radial cavity.

10. The cutting edge is the outer diameter of the engaging body. The filament cutting device according to claim 9.

11. The distal tip of the engaging body includes a surface having an angle extending from the longitudinal axis of the engaging body to the cutting edge. The filament cutting device according to claim 10.

12. The filament cutting device according to any one of claims 9 to 11 further includes a contact body disposed within the distal end of the bushing configured to prevent the distal movement of the engaging body.

13. The filament cutting device according to claim 12, wherein the contact body includes a tapered proximal portion that tapers proximally while decreasing in width. **Claim 14** The filament cutting device according to any one of claims 9 to 13, wherein the engaging body includes a tapered distal portion that tapers distally while decreasing in width.

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