Patent Description:
A component of accurately and efficiently performing an endoscopic tissue resection/dissection procedure is the ability to maintain traction as the boundaries of the target tissue are dissected. Traction systems that are associated with and/or provided by an endoscopic cap tend to obstruct a physician's view of the target tissue and/or interfere with accessory tools extending alongside or through the endoscope. These complications may directly contribute to increased procedure time, complexity and risk of perforation or bleeding.

A variety of advantageous medical outcomes may therefore be realized by the tissue retraction devices and related methods of use of the present disclosure.

<CIT> relates to a tissue retraction system including a first anchor, a second anchor, and an elongate coupling member extending between the first anchor and the second anchor. The system also may include a holder for receiving the first anchor, the second anchor, and the elongate coupling element. The holder may include a proximal portion and a distal portion. The distal portion may have a smaller width than the proximal portion such that the distal portion exerts a force on a proximal end of the first anchor during deployment of the first anchor from the holder. The force may move the first anchor into an open configuration for receiving tissue.

<CIT> relates to a method and device for approximation and retraction of tissue portions during a medical procedure. A tissue approximator-retractor elastic device comprises an elastic portion having a contracted length and adapted to expand to a different length to exert a contractile force, and at least three coupling rings spaced along the elastic portion for an operator to choose between the rings and couple at least two rings to at least two tissue portions to adjust a contractile force on the two tissue portions. Also disclosed is providing the device near the tissue portions, coupling a first coupling ring to a first tissue portion, choosing between the remaining coupling rings to select a second coupling ring, engaging the second coupling ring and elastically pulling the elastic portion to the second tissue portion to attach to the second tissue portion.

In one aspect, the present disclosure relates to a tissue retraction / traction device comprising a traction band comprising a compliant or semi-compliant material. A first attachment member may be pivotably attached to a first end of the traction band by a first swivel. A second attachment member may be pivotably attached to a second end of the traction band by a second swivel.

In the described and other embodiments, the compliant or semi-compliant material include rubbers, latex, elastics, thermoplastic elastomer (TPE), or combinations thereof. The first and second attachment members may include a compressible material such as polymers, plastics, shape memory metals, shape memory alloys, or combinations thereof. The first and second swivels may pivot around a longitudinal axis of the traction band. The traction band may be configured to move between a first configuration having a length of approximately <NUM> to <NUM> and a second configuration having a maximum length of approximately <NUM>. A filament is disposed along a length of the traction band. The filament may include a substantially non-compliant material configured to limit a maximum extended length of the traction band or may include a substantially compliant or semi-compliant material configured to increase a retraction force of the traction band.

In another aspect, the present disclosure relates to a tissue retraction system comprising a flexible elongate tubular member defining a working channel therethrough. A first endoscopic instrument may be disposed within the working channel. The first endoscopic instrument may include a first tissue clip attached to a distal end of the instrument. A tissue retraction device may be disposed within the working channel. A first attachment member of the tissue retraction device may be engaged with the first tissue clip.

In the described and other embodiments, the first tissue clip may be releasably attachable to the first attachment member of the tissue retraction device. The first tissue clip at a first end of the tissue retraction / traction device may be positionable in a body lumen. A second tissue clip may be positionable in the body lumen and attachable to a second end of the tissue retraction / traction device opposite the first end of the tissue retraction / traction device. A third tissue clip may be positionable in the body lumen and attachable to a portion of the tissue retraction / traction device. The tissue retraction / traction device may include a traction band comprising a compliant or semi-compliant material. A first attachment member may be pivotably attached to a first end of the traction band via a first swivel. A second attachment member may be pivotably attached to a second end of the traction band via a second swivel. The first and second swivels may allow the respective first and second attachment members to pivot around a longitudinal axis of, or otherwise move with respect to, the traction band.

In various embodiments, more than one attachment member may be provided on the second end of the tissue retraction / traction device. A first tissue clip may be releasably attachable to a first attachment member provided on the first end of the tissue retraction / traction device. The first tissue clip and the first attachment member may be engaged with a target tissue in a body lumen. A second tissue clip may be positionable in the body lumen and attachable to an attachment member provided on the second end of the tissue retraction / traction device. The second tissue clip and accompanying attachment member may be engaged with a first portion of anchoring tissue opposite the target tissue. If it is desired to adjust traction on the tissue retraction / traction device, a third tissue clip may be positionable in the body lumen and attachable to a different attachment member provided on the second end of the tissue retraction / traction device. The third tissue clip and accompanying attachment member may be engaged with a second portion of anchoring tissue opposite the target tissue and spaced apart from the first portion of anchoring tissue. If desired, any attachment member at the second end of the tissue retraction / traction device may be cut to release the clips associated therewith.

In yet another aspect, the present disclosure relates to an unclaimed method comprising inserting in a body lumen a tissue retraction / traction device loaded onto a first tissue clip of a first endoscopic instrument, advancing the first endoscopic instrument through a working channel of an elongate tubular member and beyond a distal end of the elongate tubular member, and engaging a target tissue of the body lumen with the first tissue clip to secure a first end of the tissue retraction / traction device to a wall of the body lumen.

In the described and other embodiments, the method may further include releasing the first tissue clip from the first endoscopic instrument. The method may further include withdrawing the first endoscopic instrument from within the working channel of the elongate tubular member and attaching a second tissue clip to the distal end of the first endoscopic instrument. The method may further include advancing the first endoscopic instrument through the working channel of the elongate tubular member and beyond a distal end of the elongate tubular member and engaging the wall of the body lumen with the second tissue clip to secure a second end of the tissue retraction / traction device to the wall of the body lumen. The first and second tissue clips may be engaged with opposite sides of the body lumen. The method may further include releasing the second tissue clip from the first endoscopic instrument. The method may further include manipulating the target tissue with a medical device attached to a distal end of a second endoscopic instrument.

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.

Although embodiments of the present disclosure are described with specific reference to tissue retraction / traction devices, systems and methods designed to provide traction within the gastrointestinal tract during a tissue dissection/resection procedure, it should be appreciated that such systems and methods may be used to manipulate a variety of tissues within a variety of different body lumens and/or body passages.

As used herein, the term "distal" refers to the end farthest away from the medical professional when introducing a device into a patient, while the term "proximal" refers to the end closest to the medical professional when introducing a device into a patient.

In various embodiments, the present disclosure relates generally to devices and systems configured to provide tissue retraction and cutting plane visualization independent of an endoscope during an endoscopic submucosal dissection (ESD) procedure.

Referring to <FIG>, in one embodiment, a tissue retraction / traction (such terms being used in the alternative, or simply referenced as "traction" for the sake of simplicity and without intent to limit) device <NUM> of the present disclosure may include a traction band <NUM> (e.g., elastic band, tether, stretchable elongate member, etc.) formed from or otherwise comprising a variety of compliant or semi-compliant materials. The traction band <NUM> may be an elongate cylindrical tube and may be formed hollow or solid. By way of non-limiting example, such materials may include flexible/stretchable rubbers, thermoplastic elastomer (TPE), plastics, polyethylene terephthalate (PET), and the like. A first attachment member <NUM> (e.g., loop, hook, ring, mini-snare, etc.) may be pivotably attached to a first end of the traction band <NUM> and a second attachment member <NUM> (e.g., loop, hook, ring, mini-snare, etc.) may be pivotably attached to a second end of the traction band <NUM>. In various embodiments, the first and second attachment members <NUM>, <NUM> may comprise a variety of flexible and/or compressible materials configured to compress or fold when disposed, e.g., within the working channel of an endoscopic instrument. Non-limiting examples of such flexible/compressible materials may include flexible plastics, hard rubbers, shape memory metals and/or alloys, and the like. In one embodiment, the first attachment member <NUM> may be pivotably attached to the first end of the traction band <NUM> by a first swivel <NUM> and the second attachment member <NUM> may be pivotably attached to the second end of the traction band <NUM> by a second swivel <NUM>. In various embodiments, the first and second attachment members <NUM>, <NUM> may swivel or pivot or rotate about or otherwise move with respect to a longitudinal axis of the traction band <NUM>. In addition, or alternatively, the first and second attachment members <NUM>, <NUM> may swivel or pivot about an axis perpendicular to the traction band <NUM>, an axis parallel to the traction band <NUM> and/or any plane or angle of orientation between a perpendicular axis and a longitudinal axis to the traction band <NUM>. As discussed below, the first and second swivels <NUM>, <NUM> may be configured to alleviate and/or prevent torsional strain exerted on a target tissue or opposing wall of a body lumen as the margins of the target tissue are dissected. In various embodiments, an end of the first and second swivels may be attached to the respective ends of the traction band using a suitable glue, adhesive or resin, as are commonly known in the art. In some embodiments, the first and second swivels <NUM>, <NUM> may be fixedly attached to opposite ends of the traction band <NUM> by an interference fit. For example, a portion of the respective first and second swivels <NUM>, <NUM> may be disposed in a hollow end portion of the traction band <NUM>. In some embodiments, the first and second swivels <NUM>, <NUM> may be integrally formed with the traction band <NUM>. In other embodiments, the first and second swivels <NUM>, <NUM> may be fixedly attached to opposite ends of the traction band <NUM> by an internal coupling component, disposed within and extending along the traction band <NUM>.

In one embodiment, the traction band <NUM> may be configured to move (e.g., stretch) from a first position (e.g., relaxed or non-tensioned) to a second position (e.g., extended, tensioned). By way of non-limiting example, the traction band <NUM> may have a length of approximately <NUM> to <NUM> when in the first position and may move a second position with maximum length of approximately <NUM>.

Referring to <FIG>, according to the invention, a filament <NUM> (e.g., wire, connector, band, etc.) is disposed along all or a portion of a length of the traction band <NUM> (e.g., along a longitudinal axis of the traction band between the first and second swivels <NUM>, <NUM>). In various embodiments, the filament <NUM> may be attached to an outer surface of the traction band <NUM> using a suitable glue, resin, or adhesive. In addition, or alternatively, the filament may be embedded within or integrally formed with the material(s) comprising the traction band <NUM>. In some embodiments, the filament <NUM> may be fixedly coupled to the first and/or second swivels <NUM>, <NUM>.

In one embodiment, the filament <NUM> may comprise a substantially non-compliant (e.g., rigid or non-stretchable) material configured to limit the maximum length to which the traction band <NUM> may stretch. The filament <NUM> may prevent over-stretching of the traction band <NUM> beyond a predetermined breaking point. Non-limiting examples of such non-compliant materials may include hard plastics, non-compliant rubber or polymers, metals, and the like. In another embodiment, the filament <NUM> may comprise a substantially compliant or semi-compliant material configured to increase (e.g., supplement) the traction force exerted by the traction band <NUM> when stretched.

Although <FIG> depict a single filament <NUM> disposed in a linear configuration (e.g., when stretched) along the length of the traction band <NUM>, in various embodiments, multiple filaments may be disposed along the traction band in a variety of patterns and/or configuration (e.g., zig-zag patterns, knitted patterns, wrapped helically around the traction band, etc.).

Referring to <FIG>, in one embodiment, a tissue traction device <NUM> of the present disclosure may be configured for use with a first endoscopic instrument <NUM>. In various embodiments, the first endoscopic instrument <NUM> may include a handle <NUM> operatively attached to a proximal end of a flexible elongate sheath <NUM> (e.g., catheter, etc.) and a first tissue clip <NUM> releasably attached to a distal end of the flexible elongate sheath <NUM>. The instrument <NUM> may be configured for use with an endoscope, bronchoscope, colonoscope, duodenoscope, ureteroscope, catheters, diagnostic or therapeutic tools or devices, or other types of medical devices. In one embodiment, the first tissue clip <NUM> may include first and second arms or jaws 136a, 136b configured to move upon actuation of the handle <NUM> between a first position (e.g., closed) and a second position (e.g., open). In various embodiments, in the closed position the arms or jaws 136a, 136b of the first tissue clip <NUM> may engage a target tissue <NUM> within a body lumen, e.g., a target tissue of the gastrointestinal (GI) tract. In various additional embodiments, the handle <NUM> may be further actuated to disengage (e.g., release) the first tissue clip <NUM> from the distal end of the sheath <NUM> such that the first tissue clip <NUM> remains engaged with the target tissue <NUM> after the first endoscopic instrument <NUM> has been removed from within the patient.

In one embodiment, a tissue traction system <NUM> of the present disclosure may include a first endoscopic instrument <NUM> slidably disposed within a working channel of a flexible elongate tubular member <NUM> (e.g., endoscope; <FIG>). For example, the sheath <NUM> may extend through the working channel of an endoscope for deploying a clip <NUM> in a patient. As discussed above, the first endoscopic instrument <NUM> may include a first tissue clip <NUM> attached to a distal end of a flexible elongate sheath <NUM>. In one embodiment, a tissue traction device <NUM> of the present disclosure may be attached to the first tissue clip <NUM> within the working channel of the flexible elongate member <NUM>. For example, a tissue traction system <NUM> of the present disclosure may be assembled by advancing the first endoscopic instrument <NUM> through the working channel of the flexible elongate tubular member <NUM> such that the first tissue clip <NUM> attached to the distal end of the sheath <NUM> of the first endoscopic instrument <NUM> extends distally beyond a distal end of the flexible elongate tubular member <NUM>. The handle <NUM> of the first endoscopic instrument <NUM> may be actuated to move the first tissue clip <NUM> from the first position to the second position, e.g., such that the first and second arms 136a, 136b are open/separated in a Y-shape. Either one of the first or second arms 136a or 136b may then be advanced through an opening of the first attachment member <NUM> of the tissue traction device <NUM>. The handle <NUM> may then be actuated to move the first tissue clip <NUM> from the second position to the first position and the first endoscopic instrument <NUM> may be proximally retracted to load the tissue clip and tissue traction device within the working channel of the elongate tubular member, e.g., such that the first tissue clip <NUM> and tissue traction device <NUM> are disposed (e.g., protected, shielded, hidden, etc.) within the working channel of the elongate tubular member <NUM>.

Referring to <FIG>, the tissue traction system <NUM> may then be advanced through a body lumen of a patient and the distal end of the flexible elongate tubular member <NUM> positioned adjacent to a target tissue <NUM>. The first endoscopic instrument <NUM> may then be distally advanced through the working channel to position the tissue retraction device <NUM> and first tissue clip <NUM> attached thereto beyond the distal end of the elongate tubular member <NUM>. The handle <NUM> may then be actuated to move the first tissue clip <NUM> from the first position to the second position and the open arms 136a, 136b placed in contact with a surface of the target tissue <NUM> (e.g., with either one of the first or second arms 136a or 136b extending through an opening of the first attachment member <NUM> of the tissue traction device <NUM>, as discussed above). The handle <NUM> may then be actuated to move the first tissue clip <NUM> from the second position to the first position to engage (e.g., clamp) the first tissue clip <NUM>, and the first attachment member <NUM> of the tissue traction device <NUM> attached thereto, with the target tissue <NUM>. In one embodiment, the first tissue clip <NUM> may be directly engaged with the portion of the target tissue <NUM> on which a procedure is to be performed (e.g., tissue to be dissected). Alternatively, the first tissue clip <NUM> may be engaged with the target tissue <NUM> adjacent to the portion on which a procedure is to be performed (e.g., the portion being dissected). The handle <NUM> may then be actuated to disengage the first tissue clip from the sheath <NUM> of the first endoscopic instrument <NUM>.

In one embodiment, the first endoscopic instrument <NUM> may then be withdrawn from within the working channel of the flexible elongate tubular member <NUM> and a second tissue clip <NUM> attached to the distal end of the sheath <NUM>. The first endoscopic instrument <NUM> may then be advanced back through the working channel to position the second tissue clip <NUM> beyond the distal end of the flexible elongate tubular member <NUM>. The handle <NUM> of the first endoscopic instrument <NUM> may then be actuated to move the second tissue clip <NUM> from the first position to the second position, e.g., such that the first and second arms 137a, 137b are open/separated in a Y-shape. Either one of the first or second arms 137a or 137b may then be advanced through an opening of the second attachment member <NUM> of the tissue traction device <NUM> within the body lumen. The first endoscopic instrument <NUM> may then be distally advanced through the working channel such that the traction band <NUM> of the tissue traction device <NUM> engaged with the first or second arms 137a, 137b of the second tissue clip <NUM> moves (e.g., stretches) from the first position to an extended/stretched second position. The arms 137a, 137b of the second tissue clip <NUM> may then be placed in contact with a wall of the body lumen opposite the target tissue <NUM>. The handle <NUM> may then be actuated to move the second tissue clip <NUM> from the second position to the first position to engage (e.g., clamp) the second tissue clip <NUM>, and the second attachment member <NUM> of the tissue traction device <NUM> attached thereto, with the wall of the body lumen opposite the target tissue <NUM>. The handle <NUM> may then be actuated to disengage the second tissue clip <NUM> from the sheath <NUM> of the first endoscopic instrument <NUM>, thereby placing the target tissue <NUM> under tension/traction by the stretched traction band <NUM> of the tissue traction device <NUM>. Although the traction band <NUM> may have a maximum second (e.g., stretched) length of approximately <NUM>, in various embodiments sufficient traction force may be provided by a traction band having a second length of approximately <NUM> to <NUM>.

In various embodiments, the first endoscopic instrument <NUM> may then be removed (e.g., withdrawn) from the working channel of the elongate tubular member <NUM> and a second endoscopic instrument <NUM> advanced through the working channel to position a second medical device <NUM> (e.g., an electrocautery knife, resection tool, etc.) attached to a distal end of the second endoscopic instrument adjacent to the target tissue <NUM>. A procedure may then be performed on the target tissue <NUM> (e.g., the target tissue may then be dissected) using the second medical device <NUM> while the tissue traction device <NUM> provides tension/traction on the target tissue <NUM>. For instance, the tissue traction device <NUM> may provide tension/traction away from the cutting plane and without impeding/blocking visualization from the distal end of the flexible elongate tubular member <NUM>.

Referring to <FIG>, in one embodiment, the direction or angle or amount of traction may be adjusted during the procedure using a third tissue clip <NUM>. For example, a third tissue clip <NUM> may be attached to the distal end of the sheath <NUM> of the first endoscopic instrument <NUM> and the first endoscopic instrument advanced through a second working channel of the elongate tubular member <NUM> to position the third tissue clip <NUM> beyond the distal end of the elongate tubular member <NUM>. The handle <NUM> of the first endoscopic instrument <NUM> may then be actuated to move the third tissue clip <NUM> from the first position to the second position, e.g., such that the first and second arms 138a, 138b are open/separated in a Y-shape. The first endoscopic instrument <NUM> may then be maneuvered to position the stretched traction band (e.g., engaged with the wall of the body lumen by the first and second tissue clips <NUM>, <NUM>) between the first and second arms 138a, 138b of the third tissue clip <NUM>. The arms 138a, 138b of the third tissue clip <NUM> may then be placed in contact with another/second portion of the wall of the body lumen opposite the target tissue <NUM>, drawing a portion of the traction band <NUM> towards the other/second portion of the wall of the body lumen to apply traction to the target tissue <NUM>. The handle <NUM> may then be actuated to move the third tissue clip <NUM> from the second position to the first position to engage (e.g., clamp) the third tissue clip <NUM> (along with the traction band <NUM>) with the other/second portion of the wall of the body lumen opposite the target tissue <NUM>. The handle <NUM> may then be actuated to disengage the third tissue clip <NUM> from the sheath <NUM> of the first endoscopic instrument <NUM>, thereby providing traction to the target tissue in a different direction or plane.

Referring to <FIG>, in another embodiment, the direction or angle or amount of traction may be adjusted during the procedure using a third tissue clip and moving the position of the second end of the traction band (opposite the first end which is coupled to the target tissue). In various embodiments, once a first attachment member <NUM> (shown in cross-section with a jaw of a first tissue clip <NUM> extending therethrough) is coupled to target tissue <NUM>, such as via a first tissue clip <NUM>, the second end of the traction band <NUM> is extended to couple a second attachment member <NUM> at the second end of the traction band <NUM> to another/second portion of the wall of the body lumen opposite the target tissue <NUM> to apply traction to the target tissue <NUM>. As illustrated in <FIG>, more than one second attachment members <NUM> may be coupled directly or indirectly to the second end of the traction band. Referring to <FIG>, a traction device <NUM> is shown with at least two attachment members 214a, 214b, such as in the form of hoops or loops, may be coupled to the second end of the traction band <NUM>. Referring to <FIG>, each attachment member 214a', 214b' may be coupled to the traction band <NUM> via a respective stem 215a, 215b. Additional attachment members with or without stems may be provided, and are not shown only for the sake of simplifying the illustrations of the embodiments and not with intent to limit the disclosure. A first attachment member 214a, 214a' may be initially coupled to a first anchoring tissue position (similar to as shown in <FIG>). If and when it is desired to modify traction, a third clip is used (such as the third clip <NUM> described with reference to <FIG>) to engage a different attachment member (such as attachment member 214b, 214b') at the second end of the traction band, such as attachment member 215b, 215b'. The first attachment member at the second end of the traction band may then be cut, either through the loop of the attachment member 214a (such as in the embodiment illustrated in <FIG>) or through the stem element 215a coupling the attachment member 214a' to the traction band <NUM> (such as in the embodiment illustrated in <FIG>). The third clip and next attachment member may then be engaged with another/second portion of the wall of the body lumen to apply traction to the target tissue <NUM> from a different direction/angle or with increased tension or otherwise.

In various embodiments, the multiple-attachment members coupled to the second end of the traction device are coupled independent of each other, and/or separately coupled to the traction device. As such, each attachment member may function independently of the others. In some embodiments, one or more of the multiple attachment members may be coupled to the traction device via a swivel connection allowing the attachment member to pivot or rotate about or otherwise move with respect to the longitudinal of the traction device.

In various embodiments, an overtube, such as, for example, the alignment member described in United States Patent Application Publication <CIT>, and titled "Tissue Retraction Device and Delivery System", may be provided over at least a portion of the traction band of a traction device formed in accordance with the present disclosure. Referring to <FIG>, an overtube <NUM> is provided over the traction band <NUM> (shown in an extended configuration to apply traction) of a traction device <NUM>. The overtube <NUM> may be provided to facilitate delivery of the traction device <NUM> through the working channel of the flexible elongate member <NUM>, such as by inhibiting or preventing folding or wrapping of the traction band <NUM> upon itself (e.g., folding back on itself) while the traction device <NUM> is advanced and/or manipulated through the working channel. The overtube <NUM> may cover the majority or all of the traction band <NUM> during advancement of the traction device <NUM>. However, once the first attachment member <NUM> (shown in cross-section with a jaw of a first tissue clip <NUM> extending therethrough) is coupled to target tissue <NUM>, such as via a first tissue clip <NUM>, and the second end of the traction band <NUM> is extended to couple the second attachment member <NUM> to another/second portion of the wall of the body lumen opposite the target tissue <NUM> to apply traction to the target tissue <NUM>, the traction band <NUM> may extend beyond the end of the overtube <NUM>, as illustrated in <FIG>. In various embodiments, the overtube may be fixed adjacent to the first end of the traction device <NUM> (e.g., adjacent to the first attachment member <NUM>, to which a first clip <NUM> may be pre-loaded, or later coupled, to attach the first attachment member to target tissue), such as by crimping (to the traction band or a swivel coupling the attachment member to the traction band or to another end element of the traction device), adhesive, or other connection known to those of ordinary skill in the art. Such fixing may be helpful in reliably positioning the overtube, such as if the target tissue is positioned above the endoscope.

In various embodiments, with the first tissue clip <NUM>, <NUM> directly engaged with the portion of the target tissue <NUM> on which a procedure is to be performed (e.g., tissue being dissected), after the procedure has been completed (e.g., the target tissue has been fully dissected), the second tissue clip <NUM> (or second and third tissue clips <NUM>, <NUM>) may be detached from the opposing wall of the body lumen. In some embodiments, the clips arms may be separated by applying a sufficient amount of force (e.g., using forceps, etc.) to either the jaws and/or a proximal end to disengage the arms of the tissue clip. Excised target tissue <NUM> and attached tissue clips may then be removed from the patient through a working channel of the elongate tubular member <NUM>. Alternatively, the traction band <NUM>, <NUM>, <NUM> or swivels <NUM>, <NUM> may be cut (e.g., using the second medical device <NUM>) and the second tissue clip (or second and third tissue clips <NUM>, <NUM>) left behind in the body lumen and expelled from the patient by the body's natural course. Or, the second attachment member <NUM>, 214a, 214b, 214a', 214b', <NUM>, or a stem 215a, 215b thereof, can be cut, releasing the traction device <NUM>, <NUM> therefrom.

The present disclosure is not limited to a tissue traction device <NUM>, <NUM>, <NUM> attached to a first tissue clip <NUM>, <NUM>, <NUM> of a first endoscopic instrument <NUM> and loaded/pre-loaded within a working channel of an elongate tubular member <NUM>. In various embodiments, some of steps involved in assembling the tissue retraction device and tissue clip(s) may occur outside of the patient's body, while some other steps involved in assembling the tissue retraction device and tissue clips(s) may occur inside the patient. The specific order and/or timing of any or all of these steps is not limited to the description of the present disclosure, but may be performed in a variety of different steps before, during or after a medical procedure. For example, in one embodiment, a tissue traction device <NUM>, <NUM>, <NUM> of the present disclosure may be loaded within the flexible elongate sheath <NUM> of the first endoscopic instrument <NUM>, advanced through the working channel of an elongate tubular member <NUM> and ejected into the body lumen by distally advancing the first tissue clip <NUM> , <NUM>, <NUM> within the sheath <NUM>. The first and second attachment members <NUM>, <NUM>, 214a, <NUM>,b, 214a', 214b', <NUM> of the tissue traction device <NUM>, <NUM>, <NUM> may then be engaged by respective first and second tissue clips <NUM>, <NUM>, <NUM>, <NUM> within the body lumen and engaged (e.g., clamped) to the target tissue and opposing wall of the body lumen as discussed above. Alternatively, a tissue traction device <NUM>, <NUM>, <NUM> of the present disclosure may be pre-loaded within a biopsy cap. The pre-loaded biopsy cap may be secured to a proximal end of the elongate tubular member <NUM> and then distally advanced over/along an outer surface of the elongate tubular member to seal a working channel at a distal end of the elongate tubular member <NUM>. The biopsy port and the tissue traction device <NUM>, <NUM>, <NUM> may then be removed from the biopsy cap within the body lumen using the first tissue clip <NUM>, <NUM>, <NUM>.

In various embodiments, the second medical instrument of the present disclosure is not limited to a tissue resection element (e.g., electrocautery knife, etc.), but may include a variety of medical instruments configured to manipulate a target tissue under traction (e.g., ablative elements, biopsy needles, injection needles, scissors, graspers, etc..

In various additional embodiments, a traction band of the present disclosure is not limited to an elongate (e.g., rectangular) and/or planar (e.g., flat) configuration, but may include a variety of different shapes and/or configurations. For example, a traction band of the present disclosure may include a coiled or helical shape; a round, oblong or spherical shape; a square shape; a triangular shape, etc..

In various additional embodiments, the first and second attachment members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be engaged with a variety of different hemostasis (e.g., Resolution™ Clip, Boston Scientific Corp. , Marlborough MA. ) and non-hemostasis tissue clips configured to secure/engage the disclosed tissue traction device to the wall of a body lumen. For example, a tissue clip contemplated for use with the disclosed tissue traction device may include a naturally open/biased configuration configured to move to a closed/clamped configuration upon actuation by a handle assembly. In addition, or alternatively, a tissue clip contemplated for use with the disclosed tissue traction device may include a naturally closed/biased configuration configured to move an open configuration upon actuation by a handle assembly. In addition, or alternatively, fasteners other than the described tissue clips may be used to secure/engage the first and second attachment members of the disclosed tissue traction device to the wall of a body lumen. Examples of fasteners may include, but are not limited to, those described in U. Patent Application Publication No. <CIT>, and titled "Tissue Retraction Device and Delivery System", along with its priority applications <CIT>, and titled "Tissue Retraction Device and Delivery System," <CIT>, and titled "Tissue Retraction Device," and <CIT>, and titled "Tissue Retraction Device and Delivery System"; <CIT>, and titled "Clip Devices, Systems, and Methods for Engaging Tissue"; and <CIT>, and titled "Endoscopic Hemostatic Clipping Apparatus". Other features and aspects of these patents and patent applications, as well as <CIT>, and titled "Tissue Traction Bands And Methods For Tissue Traction"; and <CIT>, and titled "Tether Traction Systems And Methods Of Use Thereof', may complement devices and methods of the present disclosure and may be used therewith.

Claim 1:
A tissue traction device (<NUM>, <NUM>), comprising:
a traction band (<NUM>, <NUM>, <NUM>) comprising a compliant or semi-compliant material;
a first attachment member (<NUM>, <NUM>, <NUM>) pivotably attached to a first end of the traction band (<NUM>, <NUM>, <NUM>) by a first swivel (<NUM>); and
a second attachment member (<NUM>, <NUM>, <NUM>) pivotably attached to a second end of the traction band (<NUM>, <NUM>, <NUM>) by a second swivel (<NUM>), and
a filament (<NUM>) disposed along a length of the traction band (<NUM>, <NUM>, <NUM>),
wherein the filament (<NUM>) comprises a substantially non-compliant material configured to limit a maximum extended length of the traction band (<NUM>, <NUM>, <NUM>), or wherein the filament (<NUM>) comprises a substantially compliant or semi-compliant material configured to increase a retraction force of the traction band (<NUM>, <NUM>, <NUM>).