Patent Description:
Access to and severing of one or more filaments during a medical procedure, e.g., a filament in use as a tether in a tissue dissection procedure, may be difficult to perform by a medical professional because of remote access to the filament, visualization, tortious anatomies, establishing sufficient shear force, or the like. <CIT> discloses a medical ligature tool which includes a holding member which includes distal lateral holes and proximal lateral holes through which the open ends of a ligature wire are guided. A cutting member is provided to cut the ligature wire. <CIT> discloses a surgical crimping instrument for crimping a sleeve onto a suture. A cutting edge is provided for cutting the suture.

A variety of advantageous medical outcomes may be realized by the embodiments of the present disclosure.

The presently claimed invention defines filament cutting devices according to claims <NUM> and <NUM>. Further developments of the herein claimed invention are described in the dependent claims. Various embodiments of filament cutting devices and systems are described herein. For example, use of filament cutting devices in systems including tether devices having filaments, which may be delivered into a body lumen of a patient and deployed to apply traction to tissue during a dissection procedure, e.g., endoscopic mucosal resection and/or endoscopic submucosal dissection (EMR/ESD), and which may be retrieved after the procedure by severing the filament with such filament cutting devices, are described. Exemplary tether devices and/or tether delivery devices for use together, alone, and/or in combination with filaments cutting devices, in such systems or other systems, are also described herein.

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

In various of the described and other aspects, a proximal portion of the cavity may include an angled sloping surface. A distal portion of the cavity may include an innermost curvature of the cavity defining a hook shape. The innermost curvature of the cavity may extend radially within the engaging body a length greater than <NUM>% of a diameter of the engaging body. The cutting edge may be at a distal tip of the bushing. A cutting cavity may be defined along a length of the bushing, and the cutting edge may be along the cutting cavity. The outer sheath may comprise winding coils, and a distal tip of the outer sheath may comprise a ground outer surface where the bushing is coupled to the outer sheath. A proximal portion of the outer sheath may include a smaller inner diameter than a remainder of the outer sheath, and the proximal portion of the outer sheath may include a smaller outer diameter than the remainder of the outer sheath. The engaging body may include a second cavity substantially opposing the first cavity about a longitudinal axis of the engaging body. The engaging body may include a substantially square outer perimeter that substantially matches an inner perimeter of the bushing.

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

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

In an aspect, a filament cutting device may include an outer sheath. A bushing may be coupled to a distal end of the outer sheath. The bushing may include a cavity. A cutter may extend across the cavity and may be configured to sever the filament. The cavity may be defined along a length of the bushing and may be configured to capture a portion of a filament within the cavity. The cutter may be a blade having an edge extending substantially parallel with a longitudinal axis of the filament cutting device. The cavity may be defined transversely across a distal tip of the bushing. The cutter may be an activatable wire configured to melt the filament.

In an aspect, a filament cutting device may include an outer sheath. A bushing may be coupled to a distal end of the outer sheath. An inner diameter of the bushing may be a cutting edge at a distal tip of the bushing. An actuation wire may be slidably extendable within the outer sheath and bushing. An engaging body may be coupled to a distal end of the actuation wire. The engaging body may include an outer surface having a diameter that substantially matches an inner diameter of the cutting edge of the bushing. A cavity may be defined along a length of the engaging body and may be configured to capture a portion of the filament within the cavity. Movement of the actuation wire and engaging body with the filament captured within the cavity may cause the cutting edge to sever the filament. The filament may be positionable at least partially in the cavity of the engaging body such that in response to proximal movement of the engaging body into the bushing, the filament is severable via the bushing and/or an edge of the cavity.

In another aspect, a system may include a filament cutting device, such as the filament cutting devices described above and elsewhere herein. The system may include a tether device. The system may include a tether delivery device.

In an aspect, a tether device may include a tether having a distal end, a proximal end, and a stretchable elongate body extending therebetween. The proximal end of the tether may be configured to be attached to a deployable clipping device at a distal end of a delivery catheter. The distal end of the tether may be configured with a loop extending from a neck. The loop may be configured to be engaged by a second deployable clipping device at the distal end of a delivery catheter. The loop and neck may comprise a filament that may be severable by a filament cutting device, such as the filament cutting devices described above and elsewhere herein.

The present disclosure is not limited to the particular embodiments 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 to which the disclosure belongs.

The terms "comprises" and/or "comprising," or "includes" and/or "including" when used herein, specify the presence of stated features, regions, steps elements and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and/or groups thereof. As used herein, the conjunction "and" includes each of the structures, components, features, or the like, which are so conjoined, unless the context clearly indicates otherwise, and the conjunction "or" includes one or the others of the structures, components, features, or the like, which are so conjoined, singly and in any combination and number, unless the context clearly indicates otherwise. The term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

Various embodiments according to the present disclosure are described below. As used herein, "proximal end" refers to the end of a device that lies closest to the medical professional along the device when introducing the device into a patient, and "distal end" refers to the end of a device or object that lies furthest from the medical professional along the device during implantation, positioning, or delivery.

The term "about", in the context of numeric values, generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (i.e., having the same function or result). Other uses of the term "about" (i.e., in a context other than numeric values) may be assumed to have their ordinary and customary definition(s), as understood from and consistent with the context of the specification, unless otherwise specified. The recitation of numerical ranges by endpoints includes all numbers within that range, including the endpoints (e.g. <NUM> to <NUM> includes <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>).

Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it would be within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described, unless clearly stated to the contrary.

Throughout the disclosure, although embodiments of a filament cutting device, tether device, and/or tether delivery device may be described with specific reference to medical devices and systems and procedures within the digestive system, it should be appreciated that such medical devices and methods may be used in association with tissues of the abdominal cavity, gastrointestinal system, thoracic cavity, urinary and reproductive tract and the like. Moreover, a variety of medical procedures may benefit from the presently disclosed medical devices and procedures, including, for example, Endoscopic Submucosal Dissection (ESD), Peroral Endoscopic Myotomy (POEM), cholecystectomy and Video-Assisted Thorascopic Surgery (VATS) procedures. The structures and configurations, and methods of deploying, in order to stabilize, manipulate and provide a clear field of view may find utility beyond dissection.

Referring to <FIG>, an embodiment of a filament cutting device is depicted including an outer sheath <NUM> for extending within a body lumen of a patient. A filament may be a component connecting other elements together for performing a medical procedure (see <FIG> and <FIG>), or a filament may be a suture used for suturing or other closing of tissue. After performing the medical procedure, the filament may need to be severed to complete the procedure and remove components from the patient.

A distal end of the outer sheath <NUM> of the device is illustrated with an engaging body <NUM> extended distally out of the outer sheath <NUM>. The engaging body <NUM> is extendable distally and proximally through the outer sheath <NUM>. The outer sheath <NUM> may be formed as a coil, e.g., to allow for increased bending motion in a tortuous anatomy. A proximal end of the device includes a handle <NUM> for manipulating the device and the engaging body <NUM> with respect to the outer sheath <NUM>. The handle <NUM> is depicted with a finger slide <NUM> for translating the engaging body <NUM> along a longitudinal axis of the device relative to the outer sheath <NUM>, and a rotating knob <NUM> for rotating the engaging body <NUM> about the longitudinal axis.

Referring to <FIG>, an embodiment of an actuation element <NUM> is depicted within an inner sheath <NUM>. The actuation element <NUM> may be connected to an engaging body such that the actuation element <NUM> and/or the inner sheath <NUM> may be translated proximally or distally or may be rotated about a longitudinal axis of a device to manipulate the engaging body relative to an outer sheath of the device. The actuation element <NUM> may be slidable with respect to the inner sheath <NUM> or they may axially extend together. The inner sheath <NUM> and the actuation element <NUM> may be disposed within an outer sheath of a device. The actuation element <NUM> may comprise a stiffer material (e.g., nitinol or the like) than that of the inner sheath such that the actuation element <NUM> may axially translate through the inner sheath <NUM> and/or the device. The inner sheath <NUM> may comprise a less stiff material (e.g., PTFE or the like) than the actuation element <NUM> such that contact of the stiffer actuation element <NUM> with the outer sheath is reduced. The actuation element <NUM> may be axially translated within the inner sheath <NUM> without substantial contact with the outer sheath, thereby reducing frictional forces between the substantially axial translation of the actuation element <NUM> and the outer sheath. The actuation element <NUM> and/or the inner sheath <NUM> may be coated, e.g., with silicone or the like to reduce friction. An actuation element <NUM> may be, e.g., a wire, a rod, or the like. An actuation element <NUM>, such as an actuation wire, of any embodiment described herein or otherwise within the scope of the present disclosure may or may not include an inner sheath <NUM>.

Referring to <FIG>, an embodiment of a filament cutting device is illustrated including an outer sheath <NUM> extending from a proximal end of the device to a distal end of the device. A slidable body <NUM> (e.g., a finger slide) may be axially translated (e.g., in the direction of the arrows <NUM>) by a hand (e.g., index and middle fingers of a hand) of a medical professional along a longitudinal axis of a handle <NUM> at the proximal end of the device to axially translate an actuation wire <NUM> and engaging body <NUM> with respect to the outer sheath <NUM> and a filament <NUM> to be cut. It is understood that in some embodiments, the handle <NUM> may translate axial movement of the outer sheath <NUM> relative to the actuation wire <NUM> and engaging body <NUM>, such that the outer sheath <NUM> is retractable and advanceable while the actuation wire <NUM> and engaging body <NUM> remain stationary.

Referring to <FIG>, the filament cutting device of <FIG> is illustrated including a rotatable body <NUM> at the handle <NUM> that may be rotated about the longitudinal axis of the proximal end of the device (e.g., in the direction of the arrows <NUM>) by a hand (e.g., thumb and finger of a hand) of a medical professional to rotate the actuation wire <NUM> and engaging body <NUM> with respect to the outer sheath <NUM> and a filament <NUM> to be cut.

Referring to <FIG> and <FIG>, a cross-sectional view of the handle <NUM> proximal end of the filament cutting device of <FIG> and <FIG> is illustrated with the actuation wire <NUM> extending through the proximal end of the device. A proximal end of the actuation wire <NUM> is coupled to a shaft <NUM> that is rotatably coupled to the slidable body <NUM>. An axial translation of the slidable body <NUM> axially translates the shaft <NUM> and the actuation wire <NUM>. The actuation wire <NUM> is coupled to a tubular member <NUM>. The tubular member <NUM> extends through the rotatable member <NUM> such that rotation of the rotatable member <NUM> translates rotation to the tubular member <NUM> and the actuation wire <NUM>. In various embodiments, the tubular member <NUM> may be a cannula, a hypotube, or the like, and may have a cross-sectional shape that is round, oblong, square, rectangular, a combination thereof, or the like for translating rotation between the rotatable member <NUM> and the actuation wire <NUM>. The tubular member <NUM> may extend solely within the proximal end of the filament cutting device (e.g., only extending within the handle <NUM>), or the tubular member <NUM> may also extend distally along the actuation wire <NUM> to a distal end of the filament cutting device. In various embodiments, the actuation wire <NUM> may include an inner sheath (e.g., the inner sheath <NUM> of <FIG>). The inner sheath may also be coupled to the shaft <NUM>. In various embodiments, the tubular member may be an inner sheath (e.g., the inner sheath <NUM> of <FIG>).

Referring to <FIG>, a proximal portion of an assembled filament cutting device according to an embodiment of the present disclosure is illustrated including a handle <NUM>. The handle <NUM> includes a slidable body <NUM> for manipulating the device axially and a rotatable body <NUM> for manipulating the device rotationally. The mechanics for axial and rotational movement may be configured identical to or substantially similar to that described above with respect to the embodiments of <FIG>. A proximal portion of an outer sheath <NUM> includes a strain relief tube <NUM> that is coupled to an outer surface of the outer sheath <NUM> by a heat shrink tube <NUM>. A strain relief tube <NUM> may comprise of a material such as polypropylene or the like. <FIG> illustrates the unassembled device of <FIG>, revealing a proximal end 409p of the strain relief tube <NUM> including a flare having larger outer and inner diameters than a remainder of the tube <NUM>. The proximal end 409p of the tube <NUM> is coupled to the handle <NUM> by securing the proximal end 409p to a threaded protrusion <NUM>. An actuation wire <NUM> extends from the handle <NUM>, through the threaded protrusion <NUM>, and through the outer sheath <NUM>. The flare of the proximal end 409p may be placed over and/or adjacent the protrusion <NUM> along the actuation wire <NUM> to assemble the device. The strain relief tube <NUM> is coupled to the handle <NUM> by a cap <NUM> mating with the threaded protrusion <NUM> such that the flare of the proximal end 409p of the tube <NUM> is held (e.g., compressed, constrained, etc.) between the cap <NUM> and the threaded protrusion <NUM>. The heat shrink tube <NUM> when melted couples the strain relief tube <NUM> to the outer sheath such that a proximal end 411p of the heat shrink tube bonds to the strain relief tube <NUM> and a distal end 411d of the heat shrink tube <NUM> bonds to the outer sheath <NUM>.

Referring to <FIG>, a distal end of an embodiment of a filament cutting device is illustrated including an engaging body <NUM> distally extendable out of a bushing <NUM> coupled to a distal end of an outer sheath <NUM>. The engaging body <NUM> is distally extendable relative to a filament <NUM> for severing via translation of an actuation wire <NUM> coupled to the engaging body <NUM> relative to the outer sheath <NUM>.

In various embodiments, an outer diameter of an engaging body may substantially match an inner diameter of a bushing. A bushing may be a cylindrical tube for receiving an engaging member that may be substantially cylindrical. One or both of an engaging body and a bushing may be substantially straight along a longitudinal axis of the engaging body and/or the bushing. An engaging body and/or bushing may be constructed so that one or both are more rigid than an actuation wire for the engaging body (e.g., a wider or thicker engaging body than an actuation wire) and/or the shaft of the outer member that is connected to the bushing. The more rigid construction of the engaging body and/or bushing may provide the strength to sever a filament working in combination, while the less rigid actuation wire and outer member shaft for the bushing may provide flexibility to navigate tortious anatomies and may allow for bending along pathways of anatomy. The relative rigidity and width of the engaging body compared to the bushing may also improve pushability of engaging body through the outer member. A lubricious fluid or coating may be applied to one or both of the bushing and/or the engaging body such that they are slidable with respect to each other. In various embodiments, an engaging body or a bushing may comprise stainless steel, <NUM> stainless steel, nitinol, a polymer, or the like.

Referring to <FIG>, the engaging body <NUM> of <FIG> is proximally translated relative to the bushing <NUM> and the filament <NUM>. The filament <NUM> is captured within a substantially radial cavity <NUM> of the engaging body <NUM>. The filament <NUM> may be captured by proximal translation of the engaging body <NUM> with the filament <NUM> sliding along an outer surface of the engaging body <NUM>. The filament <NUM> may slide along an angled sloping surface <NUM> of a proximal portion of the engaging body <NUM> that defines a perimeter of the cavity <NUM>. The angled sloping surface <NUM> may be a lead-in for the filament <NUM> until contacting an innermost curvature of the cavity <NUM> defining a hook portion <NUM>. The hook portion <NUM> may be formed so that the filament <NUM> is substantially perpendicular across the bushing <NUM> when the engaging body <NUM> is aligned with the bushing <NUM>. For example, the innermost curvature of the cavity <NUM> may be defined on two sides of the engaging body <NUM>. Each side may be positioned relative to each other such that the filament <NUM> may be perpendicular relative to the engaging body <NUM> and/or bushing <NUM>. That is, one side of the filament may not be positioned at an angle relative to the engaging body <NUM> or bushing <NUM> different from another side of the filament across the engaging body <NUM> or bushing <NUM>. The filament <NUM> may be prevented from moving distally past the cavity <NUM> by contacting a distal portion <NUM> of the engaging body <NUM> that extends proximally at the perimeter of the cavity <NUM>. Although the cavity <NUM> is depicted as an aperture including a lumen of the engaging body <NUM>, in various embodiments the engaging body <NUM> may be solid and the radial cavity <NUM> may instead be defined by a solid engaging body <NUM> (e.g., as illustrated in <FIG>). In various embodiments, the angled sloping surface <NUM> may be uniform with the remainder of the perimeter of the cavity <NUM>, may wider at the surface <NUM> and uniform along the remainder of the perimeter of the cavity <NUM>, or may be wider at the angled sloping surface <NUM> and taper along the perimeter of the cavity <NUM>. A wider surface <NUM> and/or a tapering perimeter of the cavity <NUM> may assist with capturing and positioning of the filament <NUM> within the cavity <NUM>.

Referring to <FIG>, the engaging body <NUM> of <FIG> may be translated proximally with respect to the outer sheath <NUM> and within the bushing <NUM> of the outer sheath <NUM> with the filament <NUM> captured within the cavity <NUM>. The bushing <NUM> includes a lumen defined at a distal end of the bushing <NUM> by a substantially sharp edge <NUM> (e.g., compared to an atraumatic blunt outer edge or surface of the distal end of the bushing <NUM>). The engaging body <NUM> is substantially straight along a longitudinal axis of the engaging body <NUM> and is aligned with the bushing <NUM>. An outer diameter of the engaging body <NUM> may substantially match, or be a slip fit to, an inner diameter of the bushing <NUM> at the edge <NUM> such that as the filament <NUM> is proximally translated to the edge <NUM> by the cavity <NUM> of the engaging body <NUM>, a shear force between the edge <NUM> and the outer surface of the engaging body <NUM>, or an edge defining a distal portion of the cavity <NUM>, severs the filament <NUM>. In various embodiments, the edge defining the cavity <NUM> (e.g., the hook portion <NUM> of the cavity) may be substantially sharp and/or the edge <NUM> of the bushing <NUM> may be substantially sharp. In various embodiments, the bushing <NUM> and outer sheath <NUM> may be distally translatable with respect to the engaging body <NUM> and the filament <NUM>.

Referring to <FIG>, the engaging body <NUM> of <FIG> may be further proximally translated within the bushing <NUM> and the outer sheath <NUM> such that a severed portion (not illustrated) of the filament <NUM> is captured within the bushing <NUM> and/or the outer sheath <NUM> for removal. It is also understood that the filament <NUM> may be severed at a single point by the bushing <NUM> and/or the cavity <NUM> such that no additional portion of the filament <NUM> is captured within the bushing <NUM> and/or the outer sheath <NUM>. The device may be removed from the patient with the cut filament <NUM> left temporarily (e.g., graspers or other end effectors may secure and remove the cut filament <NUM>) or permanently within the patient.

With reference to <FIG>, a side view profile (and accompanying detail view) of a cavity <NUM> of an embodiment of an engaging body <NUM> is illustrated. The engaging body <NUM> includes a decreasing outer diameter in a proximal direction along the engaging body <NUM> to a proximal portion of the engaging body <NUM> that may couple to an actuation wire. The diameter may be tapered to guide in the engaging body <NUM> relative to the bushing and/or an outer sheath without having to be in exact alignment (e.g., axially along a longitudinal axis of either/both of the engaging body <NUM> and the bushing). In some embodiments, the engaging body <NUM> may be a constant diameter along its length. The cavity <NUM> may have a depth <NUM> from an outer surface of the engaging body <NUM> that is larger than <NUM>% of an outer diameter <NUM> of the engaging body <NUM>. In various embodiments, the depth <NUM> may have a length that is about <NUM>% of the outer diameter <NUM>. The profile of the cavity <NUM> may have numerous shapes including a hook-like shape, which may aid in retaining a filament when contacting the innermost surface of the cavity <NUM>. Exemplary dimensions of the profile of the cavity <NUM> may include, e.g., that a lead-in angled surface of a proximal portion of the cavity <NUM> includes an angle of about <NUM>° from an outer surface of the engaging body <NUM>. A lead-out angled surface distal to the lead-in angled proximal surface of the cavity <NUM> may include an angle of about <NUM>° from an outer surface of the engaging body <NUM>. Angles herein can vary and be chosen as desired depending on a given application, e.g., a lead-in angled proximal surface and/or a lead-out angled surface of the cavity <NUM> may be about <NUM>° to about <NUM>° from the outer surface of the engaging body <NUM>. It will be appreciated that other dimensions are contemplated and within the scope of the present disclosure.

In various embodiments, an engaging body and/or a bushing may include a cavity as described herein. A filament may be captured by axial translation of one or both of an engaging body or a bushing. A filament may slide along an outer surface of an engaging body and/or a bushing. A filament may slide along an angled sloping surface of a proximal or distal portion of an engaging body or a bushing that defines a perimeter of the cavity. A filament may be prevented from moving out of and/or past the cavity by contacting a perimeter of the cavity that extends back towards an opposing end of the cavity (e.g., forming a hook-like shape).

With reference to <FIG>, a cross-sectional view of an embodiment of a bushing is illustrated including a lumen <NUM> therethrough. The lumen <NUM> has a proximal portion 704p having a wider diameter than a distal portion 704d such that the proximal portion 704p of the lumen <NUM> may be disposed about a distal end of an outer sheath. The distal portion 704d of the lumen <NUM> has a diameter <NUM> that may substantially match an outer diameter of an engaging body such that an internal edge <NUM> of a distal end of the bushing may create a shear force with the engaging body sufficient to sever a filament. The bushing may be fixedly coupled to the distal end of the outer sheath, e.g., by welding, soldering, brazing, adhesive, gluing, mechanical fasteners, and the like. In some embodiments, the outer sheath and the bushing may be integrally formed, and in other embodiments, the outer sheath and the bushing may be joined together.

Referring to <FIG>, an embodiment of an outer sheath <NUM> is illustrated (with accompanying cross-sectional views respectively along lines A-A and B-B) comprising a coiled body. The coiled body may be formed with a variable outer diameter over one or more mandrels. An outer sheath <NUM> having a coiled body may allow for more radial flexibility and axial stiffness than a solid uniform-walled outer sheath. A proximal portion 808p of the outer sheath <NUM> has a smaller inner diameter and a smaller outer diameter than the remainder of the outer sheath <NUM>, which may assist with maintaining a lower profile and maneuverability compared to a remainder of the device. The proximal portion 808p of the outer sheath <NUM> extends distally to a tapered section 808t of the outer sheath <NUM>. The tapered section 808t includes a distally increasing outer diameter and a distally increasing inner diameter. The tapered section 808t extends to a distal portion 808d of the outer sheath <NUM> that is depicted with a substantially uniform outer diameter. The distal portion 808d may be treated by grinding (e.g., longitudinally grinding, polishing, or the like) to form the substantially uniform outer diameter. The diameter of the distal portion 808d of the outer sheath <NUM> may substantially match or be a slip fit within an inner diameter of a working channel (e.g., about <NUM> or the like) of an endoscope. A distal tip <NUM> of the outer sheath <NUM> extending from the distal portion 808d may be ground, e.g., as illustrated in <FIG>, more than the distal portion 808d is ground, such that an outer diameter of the distal tip <NUM> is smaller than the outer diameter of the distal portion 808d. The outer diameter of the distal tip <NUM> may substantially match an inner diameter of a proximal portion of a lumen of a bushing such that the bushing may be disposed over and attachable to the distal tip <NUM>, and the outer diameter of the bushing may substantially match the outer diameter of the distal portion 808d of the outer sheath <NUM>. The inner diameter of the distal tip <NUM> may match the inner diameter of the distal portion 808d of the outer sheath <NUM> and an inner diameter of a distal portion of the bushing such that an engaging body may slidably translate within the distal portion 808d and distal tip <NUM> of the outer sheath <NUM> and through the bushing. In various embodiments, an outer sheath <NUM> may have a substantially uniform outer diameter along its length.

With reference to <FIG>, an engaging body <NUM> is illustrated including a transverse distal tip 900t surface transitioning to a sloped surface <NUM> extending proximally at an angle along a longitudinal axis of the engaging body <NUM>. The sloped surface <NUM> is substantially distal to a cavity <NUM> of the engaging body <NUM> along the length of the engaging body <NUM>. The cavity <NUM> is illustrated as being formed within or defined by a solid body of the engaging body <NUM>, however the cavity <NUM> may include a substantially radial aperture formed within the engaging body <NUM>. The sloped surface <NUM> transitions to an outer circumferential surface <NUM> of the engaging body <NUM> in a proximal direction and continues extending to the cavity <NUM>. The sloped surface <NUM> may assist with capturing a filament within the cavity <NUM> of the engaging body as illustrated and discussed with respect to a sloped surface of <FIG>. The transitions between the sloped surface <NUM> and the outer circumferential surface <NUM>, and the outer circumferential surface <NUM> to the cavity <NUM>, may each include fillets <NUM> (e.g., rounded surfaces, smoothed surfaces, atraumatic surfaces, or the like). The fillets <NUM> may reduce friction with other portions of a device, another device, and/or a patient anatomy compared to non-filleted edges. During a procedure, axial viewing of an engaging body <NUM>, portions of an engaging body <NUM>, and/or the orientation of an engaging body <NUM> or a cavity <NUM> may be difficult for a medical professional to identify. The fillets <NUM> may provide surfaces that are identifiable to the medical professional compared to other surfaces of the engaging body <NUM> (e.g., by reflecting light at a different angle or reflecting light in a different shape than other surfaces of the engaging body <NUM>).

Referring to <FIG>, a distal end of an embodiment of a filament cutting device is illustrated substantially similar to that discussed with respect to <FIG>. In <FIG>, a distal portion of an engaging body <NUM> includes a sloped surface <NUM>. The sloped surface <NUM> may slide along a filament <NUM>, for example, as an actuation wire <NUM> and engaging body <NUM> are translated distally into contact with the filament <NUM>. During a distally-traveling contact of the engaging body <NUM> with the filament <NUM>, the filament <NUM> may slide along the sloped surface <NUM> proximally toward a cavity <NUM> of the engaging body <NUM>. Contacting a distal tip of an engaging body <NUM> including the sloped surface <NUM> with the filament <NUM> may be easier to facilitate capture of the filament <NUM> within the cavity <NUM> compared to a distal tip of an engaging body <NUM> that has a substantially transverse surface that may collide with the filament <NUM> and direct the filament <NUM> away from the cavity <NUM>. The engaging body <NUM> may include filleted surfaces along the outside of the engaging body from the distal tip to the cavity <NUM> to help prevent the filament <NUM> from being damaged or severed prematurely. The filament <NUM> may be captured within the cavity <NUM> and proximally retracted for severing within a bushing <NUM> of an outer sheath <NUM> by proximal translation of the engaging body <NUM> relative to the outer sheath <NUM>. The engaging body <NUM> may remain stationary after capturing the filament <NUM>, and the bushing <NUM> and outer sheath <NUM> may extend distally to sever the filament <NUM> as the engaging body <NUM> is received into the outer sheath <NUM>. The engaging body <NUM> may be translated distally with respect to the bushing <NUM> to eject a severed portion <NUM> of the filament <NUM>.

In various embodiments, a filament may be severed in a variety of ways. For example, a filament may be severed by a cut, a plastic break, a tensioned break, or the like that may be performed by a cutter that is mechanical, electrical, chemical, or the like. In various embodiments, a filament of a device may be cut during or at the termination of a medical procedure. Severing a filament may be performed for a variety of reasons including, e.g., to release a device, to remove a filament such as a suture, to release tension between devices, between a device and an anatomy, between anatomies, between a first portion of an anatomy and a second portion of an anatomy, or the like.

Referring to <FIG>, an embodiment of an engaging body <NUM> and a bushing <NUM> are illustrated. The engaging body <NUM> may be coupled to an actuation wire and the bushing <NUM> may be coupled to an outer sheath as described herein. The engaging body <NUM> is slidable within a lumen <NUM> of the bushing <NUM>. The engaging body <NUM> has a non-circular perimeter (e.g., square, rectangular, polyhedral, or the like) that substantially matches the non-circular lumen <NUM>. A cavity <NUM> of the engaging body <NUM> may be used to capture a filament <NUM> to sever the filament <NUM> between the cavity <NUM> and the bushing <NUM> via translation of the engaging body <NUM> toward the bushing <NUM> and/or translation of the bushing <NUM> toward the engaging body <NUM>. In embodiments, such as the one illustrated, the perimeter of the engaging body <NUM> and the cavity <NUM> do not include any curved surfaces. In some embodiments, non-circular perimeter geometries of the engaging body <NUM> may be advantageous in that fewer inputs, less time, and/or tolerance controls may be utilized than others for manufacturing.

Referring to <FIG>, an embodiment of an engaging body <NUM> is illustrated including a first cavity <NUM> and a second cavity <NUM>. The cavities <NUM>, <NUM> are oriented substantially opposite each other about a longitudinal axis ℓ of the engaging body <NUM>. The second cavity <NUM> allows for another portion of the engaging body <NUM> to capture a filament. The substantially opposite orientation of the cavities <NUM>, <NUM> allows for minimal rotation of the engaging body <NUM> in order to capture a filament (i.e., a smaller rotation of the engagement member <NUM> about the longitudinal axis ℓ may be required to expose a cavity <NUM>, <NUM> to a filament compared to a larger rotation that may be required with an embodiment having only a first cavity <NUM>). Both cavities <NUM>, <NUM> are arranged such that they have a depth extending through the longitudinal axis ℓ (i.e., beyond <NUM>% of the outer diameter of the engaging body <NUM>); however, in various embodiments, the cavities may extend up to or radially short of the longitudinal axis ℓ. For example, the lead-in proximal angle of the cavities <NUM>, <NUM> with respect to an outer surface of the engaging body <NUM> may be smaller such that the cavities <NUM>, <NUM> do not radially extend past the longitudinal axis ℓ. The cavities <NUM>, <NUM> overlap with each other along the longitudinal axis ℓ and also radially overlap transversely through the longitudinal axis ℓ. However, the cavities <NUM>, <NUM> may be arranged such that they do not overlap with each other along the longitudinal axis ℓ, do not radially overlap transversely through the longitudinal axis ℓ, and/or may not be arranged substantially opposite each other about the longitudinal axis ℓ. Although two cavities <NUM>, <NUM> are illustrated, any number of cavities may be employed, e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc. Although the cavities <NUM>, <NUM> are illustrated as arranged approximately <NUM>° about the longitudinal axis ℓ, any angled arrangement may be employed, e.g., about <NUM>°, about <NUM>°, about <NUM>°, about <NUM>°, etc..

With reference to <FIG>, an embodiment of an engaging body <NUM> and a bushing <NUM> are illustrated. The engaging body <NUM> may be coupled to an actuation wire and the bushing <NUM> may be coupled to an outer sheath as described herein. The engaging body <NUM> is slidable within a lumen <NUM> of the bushing <NUM>. The engaging body <NUM> includes a substantially radial first cavity <NUM> and an angled sloping surface <NUM> of a proximal portion of the engaging body <NUM> that defines a perimeter of the first cavity <NUM>. The angled sloping surface <NUM> of the first cavity <NUM> extends to an innermost curvature of the first cavity <NUM> defining a hook portion at a second surface <NUM> of the first cavity <NUM>. Although the first cavity <NUM> is depicted as an aperture including a lumen of the engaging body <NUM>, in various embodiments the engaging body <NUM> may be solid and the radial cavity <NUM> may instead be defined by a solid engaging body <NUM> (e.g., as illustrated in <FIG>). The bushing <NUM> includes a substantially radial second cavity <NUM> that extends into the lumen <NUM>. The second cavity <NUM> includes a proximal surface <NUM> and a distal surface <NUM> that meet at a curved midportion <NUM> of the second cavity <NUM>. The proximal surface <NUM> and the distal surface <NUM> are angled such that the outer portions of the surfaces <NUM>, <NUM> are farther apart from each other compared to the inner portions of the surfaces <NUM>, <NUM> (i.e., towards the midportion <NUM>). This orientation of the proximal and distal surfaces <NUM>, <NUM> of the second cavity <NUM> forms a perimeter of the second cavity <NUM> such that the second cavity <NUM> has a wider outer portion at the outer surface of the engaging body <NUM> and a narrower inner portion at the curved midportion <NUM>.

Referring to <FIG>, the first and second cavities <NUM>, <NUM> of <FIG> may be substantially aligned to accept and capture a filament <NUM>. The bushing <NUM> may be distally extended such that the filament <NUM> enters the widest outer portion of the second cavity <NUM>. The filament <NUM> may be moved into the second cavity <NUM> along the angled perimeter of the second cavity <NUM>. The second cavity may direct the filament <NUM> proximally toward the narrowest inner portion of the second cavity <NUM>. At the inner portion of the second cavity <NUM> the filament <NUM> is proximal to the distal surface (i.e., the distal surface <NUM> of <FIG>) of the first cavity <NUM> when the cavities <NUM>, <NUM> are aligned.

Referring to <FIG>, with the filament <NUM> captured within the first and second cavities <NUM>, <NUM> of <FIG>, the engaging body <NUM> may be translated proximally with respect to the bushing <NUM>. As the first and second cavities <NUM>, <NUM> move past each other, the filament <NUM> is subjected to shearing forces between a distal perimeter outer edge <NUM> of the first cavity <NUM> and a proximal inner edge <NUM> of the perimeter of the second cavity <NUM>.

Referring to <FIG>, as the first and second cavities <NUM>, <NUM> of <FIG> move past each other across the filament <NUM>, the filament <NUM> is severed. A severed portion <NUM> of the filament <NUM> may be kept within the lumen <NUM>, withdrawn proximally through the lumen <NUM>, expelled distally through the lumen <NUM>, or expelled substantially radially out of the second cavity <NUM>.

In various embodiments, a cavity of an engaging body and/or a bushing may include various shapes, surfaces, and/or edges for engaging, accepting, trapping, moving, sliding, stopping, guiding, shearing, and/or or holding a filament or a portion of a filament. A combination of various portions of shapes and/or surfaces of cavities depicted and described with respect to a particular embodiment or embodiments may be used across other embodiments of cavities described or otherwise within the scope of the present disclosure.

Referring to <FIG>, an embodiment of an engaging body <NUM> and a bushing <NUM> are illustrated. The engaging body <NUM> may be coupled to an actuation wire and the bushing <NUM> may be coupled to an outer sheath as described herein. The engaging body <NUM> is slidable within a lumen <NUM> of the bushing <NUM>. The bushing <NUM> includes a substantially radial cavity <NUM> that extends into the lumen <NUM>. The cavity <NUM> includes a proximal surface <NUM> and a distal surface <NUM> that meet at a curved midportion <NUM> of the cavity <NUM>. The engaging body <NUM> includes a cutting edge <NUM> at a distal tip of the engaging body <NUM> at an outer diameter of the engaging body <NUM>. The distal tip of the engaging body <NUM> includes a surface <NUM> having an angle extending from a longitudinal axis ℓ of the engaging body <NUM> to the cutting edge <NUM>. The surface <NUM> extends both proximally and inwardly from the cutting edge <NUM> towards the longitudinal axis ℓ. A filament may be captured within the cavity <NUM> and the engaging body <NUM> may be translated within the lumen <NUM> toward the filament within the cavity <NUM>. A contact body <NUM> is disposed within a distal end 1402d of the bushing <NUM> that prevents distal translation of the engaging body <NUM>. The contact body <NUM> may comprise a material that is soft enough such that the cutting edge <NUM> is not damaged when it contacts the contact body <NUM> and resilient enough such that the cutting edge <NUM> may extend at least partially into the contact body <NUM> distally past a filament to ensure a complete severing a filament, for example, comprising a material such as urethane, high density polyethylene, a plasticized grade of PVC, or the like. The bushing <NUM> includes an atraumatic tip 1402t with a distally narrowing diameter such that anatomies or other instruments may not be harmed while delivering the device and/or such that narrow pathways may be easier to traverse compared to a device without the atraumatic tip 1402t.

With reference to <FIG>, an embodiment of an engaging body <NUM> and a bushing <NUM> are illustrated. The engaging body <NUM> may be coupled to an actuation wire and the bushing <NUM> may be coupled to an outer sheath as described herein. The engaging body <NUM> is slidable within a lumen <NUM> of the bushing <NUM>. The bushing <NUM> includes a substantially radial cavity <NUM> that extends into the lumen <NUM>. The cavity <NUM> includes a proximal surface <NUM> and a distal surface <NUM> that meet at a curved midportion <NUM> of the cavity <NUM>. The engaging body <NUM> includes a cutting portion <NUM> at a distal tip of the engaging body <NUM> that may be a cutting edge or a blunt surface. The cutting portion <NUM> is a distal portion of the engaging body <NUM> that tapers distally with a decreasing width. A filament may be captured within the cavity <NUM> and the engaging body <NUM> may be translated within the lumen <NUM> toward the filament within the cavity <NUM>. A contact body <NUM> is disposed within a distal end 1502d of the bushing <NUM> that prevents distal translation of the engaging body <NUM>. The contact body <NUM> comprises a tapered proximal portion <NUM> that tapers proximally with a decreasing width. With a filament captured within the cavity <NUM>, the engaging body <NUM> may be translated distally towards the contact body <NUM> such that the filament is compressed between the cutting portion <NUM> and the proximal portion <NUM> and/or sheared between the cutting portion <NUM> and the proximal portion <NUM>, thereby severing the filament.

Referring to <FIG>, an embodiment of an engaging body <NUM> and a bushing <NUM> are illustrated. The engaging body <NUM> may be coupled to an actuation wire and the bushing <NUM> may be coupled to an outer sheath as described herein. The engaging body <NUM> is slidable within a lumen <NUM> of the bushing <NUM>. The bushing <NUM> includes a substantially radial cavity <NUM> that extends into the lumen <NUM>. The cavity <NUM> includes a proximal surface <NUM> and a distal surface <NUM> that meet at a curved midportion <NUM> of the cavity <NUM>. The engaging body <NUM> includes a cutting edge <NUM> at a distal tip of the engaging body <NUM> at an outer diameter of the engaging body <NUM>. The distal tip of the engaging body <NUM> includes a surface <NUM> having an angle extending across a longitudinal axis ℓ of the engaging body <NUM> to the cutting edge <NUM>. The angled surface <NUM> may be used to trap a filament and the cutting edge <NUM> about the angled surface <NUM> may decrease a required amount of shear stress to sever a filament compared to a radial cross-sectional surface with a shorter perimeter about the surface. A filament <NUM> may be captured within the cavity <NUM> and the engaging body <NUM> may be translated within the lumen <NUM> toward the filament <NUM> within the cavity <NUM>. As the cutting edge <NUM> is translated distally past the cavity <NUM>, the cutting edge <NUM> and an inner edge of the distal surface <NUM> shear the filament <NUM>.

Referring to <FIG>, an embodiment of a filament cutting device is illustrated including a bushing <NUM> coupled to a distal end of the outer sheath <NUM>. The bushing <NUM> includes a substantially radial cavity <NUM>. The cavity <NUM> includes a proximal surface <NUM> and a distal surface <NUM> that meet at a curved midportion <NUM> of the cavity <NUM>. A cutter <NUM> extends across the cavity <NUM>. The cutter <NUM> extends substantially parallel with a longitudinal axis of the bushing <NUM>, but may be angled, e.g., parallel or normal to the proximal surface <NUM>. The cutter <NUM> includes an edge oriented substantially radially outward from the cavity <NUM>. A filament <NUM> may be captured within the cavity <NUM> and the bushing <NUM> may be translated proximally and/or radially against the filament <NUM> such that the cutter <NUM> severs the filament <NUM>. A distance between an outer surface of the bushing <NUM> to the edge of the cutter within the cavity <NUM> may be substantially equal to a diameter of a filament <NUM>, e.g., about <NUM> millimeters or the like, such that the distal surface <NUM> may be placed adjacent the filament <NUM> for manipulation of the filament <NUM> and/or to act as a backstop against the filament <NUM> for cutting. The embodiment of <FIG> has no moving parts with respect to each other, which may reduce stress on the outer sheath <NUM> and/or the filament <NUM> during operation.

Referring to <FIG>, an embodiment of a filament cutting device is illustrated including a bushing <NUM> coupled to a distal end of an outer sheath <NUM>. The bushing <NUM> includes a cavity <NUM>. The cavity <NUM> is defined substantially transversely across a distal tip 1802t of the bushing <NUM> and includes a curved midportion <NUM> of the cavity <NUM>. A cutter <NUM> extends across the cavity <NUM>. The cutter <NUM> extends substantially transversely across a longitudinal axis of the bushing <NUM>, but may be angled. The cutter <NUM> is an activatable wire configured to melt a filament. Ends <NUM>, <NUM> of the cutter <NUM> extend into the bushing <NUM> and are coupled (e.g., welded) to a first lead wire <NUM> and a second lead wire <NUM> that extend proximally along the bushing <NUM> and the outer sheath <NUM> to an energy source (e.g., a battery within a handle). The cutter <NUM> and leads <NUM>, <NUM> may be overmolded within the bushing <NUM>. The cutter <NUM> has a conductive outer surface while the leads <NUM>, <NUM> are insulated by the bushing <NUM> and/or insulative coverings along the leads <NUM>, <NUM>. The embodiment of <FIG> has no moving parts, which may reduce stress on the outer sheath <NUM> and/or a filament during operation. The cutter <NUM> may comprise various conductive materials such as nichrome, iron-chromium-aluminum alloy, or the like.

Referring to <FIG>, an embodiment of a tether device <NUM> is illustrated including an elastic, stretchable body <NUM> having first <NUM> and second ends <NUM>. An elongate tubular hollow body alignment member <NUM> is extendable at least partially over the elastic body <NUM>. The alignment member <NUM> may align and/or orient the device <NUM> within a working channel of a scope, other introducer sheath, or catheter during device <NUM> manipulation. A clip <NUM> is coupled to the first end <NUM> of the elastic body <NUM>. A neck <NUM> extends from the second end <NUM> of the elastic body <NUM> to a loop <NUM>. The clip <NUM> may be manipulated by a medical professional such that the clip <NUM>, coupled to the first end <NUM> of the tether device <NUM>, is delivered toward a tissue. The clip <NUM> may be coupled to the tissue in addition to being coupled to the first end <NUM> of the elastic body <NUM>. The loop <NUM> may be engaged by another device such as an additional clip. The additional clip may be moved to position the loop <NUM> within the additional clip jaws and to couple the additional clip to another anatomy or another portion of the tissue such that the second end <NUM> of the elastic member <NUM> extends away from the first end <NUM>. In this position, the tether device <NUM> is placed in greater axial tension compared to a relaxed state of the tether device <NUM> that is illustrated in <FIG>. In various embodiments, a clip <NUM> may be rotatable to rotate the tether device <NUM>. A clip <NUM> may be repositionable before, during, and/or after a procedure. A clip <NUM> may be a single use clip. With the tether device <NUM> and the tissue(s) coupled to the tether device <NUM> in tension, a medical procedure may be performed, e.g., resecting of the tissue. During and/or after the procedure, tension may be released by severing a filament of the tether device such as the elastic body <NUM>, the alignment member <NUM>, the neck <NUM>, and/or the loop <NUM> (see e.g., FIGS. <NUM>-5D and <FIG>). In various embodiments, the elastic body <NUM> may be severable by the cutting device. In various embodiments, an elastic body <NUM> may include one or more securing bodies at one or more ends <NUM>, <NUM> of the elastic body <NUM> that may each be coupled to a filament. An elastic body <NUM> may include an internal filament that may prevent the elastic body <NUM> from stretching beyond a desirable length. A filament of an elastic body <NUM> may comprise, extend to, or be coupled to one or more loops (e.g., loop <NUM> with or without a neck <NUM>) that can be various shapes and diameters.

Referring to <FIG>, an embodiment of a tether device is illustrated as delivered and applying tension between a target tissue <NUM> and another tissue <NUM>. An elastic body <NUM> is coupled to a first clip <NUM> at a first end of the elastic body <NUM>. The first clip <NUM> is coupled to the target tissue <NUM> for resection. A second end of the elastic body <NUM> is coupled to a second clip <NUM>. The second clip <NUM> is coupled to tissue <NUM> such that the elastic body <NUM> is in tension. A resecting tool <NUM> is delivered toward the target tissue <NUM> via an endoscope <NUM>. As the target tissue <NUM> is resected, the elastic body <NUM> pulls the first clip <NUM> and the target tissue <NUM> substantially toward the second clip <NUM> such that visualization between the endoscope <NUM>, the tool <NUM>, and the target tissue <NUM> is maintained. During or at the termination of the procedure, an embodiment of a filament cutting device may be delivered to the elastic body <NUM> to cut the elastic body <NUM>, releasing tension in the elastic body <NUM>. Various embodiments of a tether device and clip delivery device, or other delivery device for a tether device, such as the tether device and clip delivery device of <FIG>, may be used in a tissue dissection procedure, such as the procedure depicted in <FIG>.

Claim 1:
A filament cutting device, comprising:
an outer sheath (<NUM>; <NUM>; <NUM>);
a bushing (<NUM>; <NUM>; <NUM>; <NUM>) coupled to a distal end of the outer sheath (<NUM>; <NUM>; <NUM>), wherein an inner diameter of the bushing (<NUM>; <NUM>; <NUM>; <NUM>) includes a cutting edge (<NUM>; <NUM>; <NUM>);
an actuation wire (<NUM>; <NUM>) slidably extendable within the outer sheath (<NUM>; <NUM>; <NUM>) and bushing (<NUM>; <NUM>; <NUM>; <NUM>); and
an engaging body (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) coupled to a distal end of the actuation wire (<NUM>; <NUM>), the engaging body comprising a cavity (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) defined along a length of the engaging body configured to capture a portion of a filament (<NUM>; <NUM>; <NUM>; <NUM>) within the cavity (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) by axial translation of the engaging body (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) and/or the bushing (<NUM>; <NUM>; <NUM>; <NUM>); and
wherein movement of the actuation wire (<NUM>; <NUM>) and engaging body (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) with the filament (<NUM>; <NUM>; <NUM>; <NUM>) captured within the cavity (<NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>) causes the cutting edge (<NUM>; <NUM>; <NUM>) to sever the filament (<NUM>; <NUM>; <NUM>; <NUM>).