Tissue retraction device

Abstract

The present disclosure relates to the field of tissue dissection. Specifically, the present disclosure relates to medical devices that lift and retract tissue during a dissection procedure to improve visualization of target tissue and mitigate obstruction of dissection tools. In particular, the present disclosure relates to a tissue retraction device that moves from a constrained configuration to a relaxed configuration during a dissection procedure to secure and retract a peeled portion of target tissue.

Description

[0001] This application is a divisional application of the application entitled “Tissue Retraction Device” and application number 201780059734.9 filed on September 29, 2017.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of priority under 35 USC §119 to U.S. Provisional Patent Application Serial No. 62 / 402,649, filed on September 30, 2016, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0004] The present disclosure relates to the field of tissue dissection. Specifically, the present disclosure relates to medical devices that lift and retract tissue during a dissection procedure to improve visualization of the target tissue and reduce obstruction of dissecting tools. In particular, the present disclosure relates to a tissue retraction device that moves from a constrained configuration to a relaxed configuration during a dissection procedure to secure and retract a dissected portion of the target tissue. Background Art

[0005] During the dissection procedure, surgical dissection of lesions from narrow body passages, such as the digestive tract, can be inefficient and time-consuming due to poor visualization of the target tissue. This problem can be exacerbated during the surgical procedure because partially dissected target tissue blocks the working area, further reducing visibility and obstructing the dissection tool. Summary of the Invention

[0006] The present disclosure, in its various aspects, is directed to a tissue retraction device that immobilizes and retracts target tissue during a dissection procedure to improve tissue visualization and manipulation.

[0007] In one aspect, the present disclosure relates to a tissue retractor comprising an elongated flexible element and at least one guide member attached to the elongated flexible element; the elongated flexible element comprising a proximal end configured to engage a first target tissue portion and a distal end configured to engage a second target tissue portion; the at least one guide member defining a lumen extending therethrough. The elongated flexible element moves between a first (i.e., constrained, restricted, stored, or delivered) configuration and a second (i.e., relaxed, free, or deployed) configuration.

[0008] In another aspect, the present disclosure relates to a tissue retractor comprising an elongated flexible element, at least one guide member attached to the elongated flexible element, and a control wire; the elongated flexible element comprising a proximal end configured to engage a first target tissue portion and a distal end configured to engage a second target tissue portion; the at least one guide member defining a lumen extending therethrough; the control wire configured to be slidably received within the lumen of the at least one guide member, wherein the elongated flexible element moves between a first (i.e., constrained, restricted, stored, or delivered) configuration when the control wire is disposed within the lumen of the at least one guide member and a second (i.e., relaxed, free, or deployed configuration) configuration when the control wire is not disposed within the lumen of the at least one guide member. The at least one guide member may comprise a plurality of guide members attached along the length of the elongated flexible element. An end of the at least one guide member may comprise a cap. The elongated flexible element may be substantially flat when in the first configuration. The elongated flexible element may be curved along its longitudinal axis when in the second configuration. The elongated flexible element may comprise a woven mesh. Additionally or alternatively, the elongated flexible element may comprise two or more parallel elements. Two or more parallel elements can be attached to each other by the at least one guide member. A portion of the parallel elements can be configured to arch outward from the longitudinal axis of the elongated flexible element. The control wire can pass between the parallel elements when it is arranged in the lumen of at least one guide member. The proximal and distal ends of the elongated flexible element may include one or more tissue anchors, for example, tines, forks, hooks, fingers, barbs, loops and / or clamps. Additionally or alternatively, one or more stabilizers (e.g., hooks and / or barbs, etc.) can be attached to the elongated flexible element. The elongated flexible element can be formed by a polymer, including but not limited to acrylate-based polymers, polyurethane-based polymers, polynorbornene-based polymers and polylactide-based polymers. Additionally or alternatively, the elongated flexible element can be formed by a metal or metal alloy, including but not limited to platinum, tungsten, titanium, stainless steel, nickel, nickel-titanium alloy, and other alloys of the above or other metals.

[0009] In yet another aspect, the present disclosure relates to a system comprising a delivery catheter and an elongated flexible element slidably disposed within a lumen of the delivery catheter. The elongated flexible element may include a proximal end configured to engage a first target tissue portion, a distal end configured to engage a second target tissue portion, at least one guide member attached to the elongated flexible element, the at least one guide member defining a lumen extending therethrough, and a control wire configured to be slidably received within the lumen of the at least one guide member. The elongated flexible element may be movable between a first (i.e., constrained, restricted, stored, or delivered) configuration when the control wire is disposed within the lumen of the at least one guide member and a second (i.e., relaxed, free, or deployed configuration) configuration when the control wire is not disposed within the lumen of the at least one guide member. The proximal end of the control wire may extend beyond the proximal end of the delivery catheter. The delivery catheter may be slidably disposed within a working channel of an endoscope. Additionally or alternatively, the at least one guide member may be attached along the length of the elongated flexible element.

[0010] In yet another aspect, the present disclosure relates to an aspect comprising advancing a delivery catheter through a working channel of an endoscope to a position adjacent to a target tissue such that a distal end of the delivery catheter is above a first portion of the target tissue, wherein the working channel of the delivery catheter comprises an elongated flexible element comprising a proximal end configured to engage the first target tissue portion, a distal end configured to engage a second target tissue portion, at least one guide member attached to the elongated flexible element (wherein the at least one guide member defines a lumen extending therethrough), and a control wire configured to be slidably received within the lumen of the at least one guide member, wherein the elongated flexible element The method further comprises: moving the control wire between a first configuration when the control wire is disposed within the lumen of at least one guide member and a second configuration when the control wire is not disposed within the lumen of at least one guide member; advancing the control wire distally so that the distal end of the elongated flexible element engages the target tissue past a first portion of the distal end of the delivery catheter; retracting the delivery catheter proximally so that the proximal end of the elongated flexible element moves past the distal end of the delivery catheter; forcing the distal end of the delivery catheter against the proximal end of the elongated flexible element so that the proximal end of the elongated flexible element engages the second portion of the target tissue; and retracting the control wire proximally so that the control wire is removed from the lumen of at least one guide member. The method also includes advancing a tissue removal (e.g., cutting) element through a working channel of the endoscope and peeling along an edge of the target tissue as the elongated flexible element moves from the first configuration to the second configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Non-limiting embodiments of the present disclosure are described by way of example with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. In the drawings, each identical or nearly identical component is generally represented by a single reference numeral. For purposes of clarity, not every component is labeled in every figure, and not every component of every embodiment of the present disclosure is shown, where illustration is not necessary for a person skilled in the art to understand the present disclosure. In the drawings:

[0012] Figures 1A-1B Shows a constrained flat form ( Figure 1A ) and the relaxed curved form ( Figure 1B ) tissue retractor.

[0013] Figures 2A-2D Various tissue anchor configurations are shown that may be provided on an end portion of a tissue retractor according to various embodiments of the present disclosure.

[0014] Figure 3 A tissue stabilizer is shown disposed on a bottom surface of a tissue retractor according to an embodiment of the present disclosure.

[0015] Figures 4A-4B According to an embodiment of the present disclosure, a parallel configuration ( Figure 4A ) and arched form ( Figure 4B ) is part of a tissue retractor.

[0016] Figure 5 According to one embodiment of the present disclosure, a device is provided in the cavity of the delivery system. Figure 1A Tissue retractor.

[0017] Figures 6A-6D A method of deploying a tissue retractor onto target tissue according to an embodiment of the present disclosure is shown.

[0018] Figures 7A-7C FIG. 1 shows the use of a tissue retractor to perform dissection on a target tissue according to an embodiment of the present disclosure.

[0019] Figures 8A-8B Shown is another embodiment of the present disclosure in a constrained flat form ( Figure 8A ) and the relaxed curved form ( Figure 8B ) tissue retractor.

[0020] Figure 9 Two tissue retractors are shown deployed along opposing planes of target tissue according to an embodiment of the present disclosure.

[0021] Figures 10A-10B According to another embodiment of the present disclosure, the Figure 10A ) and the relaxed form ( Figure 10B ) tissue retractor.

[0022] Figures 11A-11C According to another embodiment of the present disclosure, the Figure 11A ), relaxed form ( Figure 11B ) and delivery modality ( Figure 11C ) tissue retractor.

[0023] Figures 12A-12B According to another embodiment of the present disclosure, the Figure 12A ) and the relaxed form ( Figure 12B ) tissue retractor.

[0024] It should be noted that the drawings are intended to illustrate only representative or exemplary embodiments of the present disclosure. Therefore, the drawings should not be considered as limiting the scope of the present disclosure. The present disclosure will now be described in more detail with reference to the drawings. DETAILED DESCRIPTION

[0025] Before describing the present disclosure in more detail, it should be understood that the present disclosure is not limited to the specific embodiments described and, therefore, changes may be made. It should also be understood that the terms used herein are for the purpose of describing specific embodiments only and are 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 present disclosure belongs. Finally, although embodiments of the present disclosure are described with specific reference to medical devices and systems for dissecting tissue of the digestive system, it should be understood that such medical devices can be used for dissecting tissue of the abdominal cavity, gastrointestinal system, thoracic cavity, etc. In addition, various medical procedures can benefit from the presently disclosed medical devices, including, for example, endoscopic submucosal dissection (ESD), peroral endoscopic myotomy (POEM), cholecystectomy, and video-assisted thoracoscopic surgery (VATS) procedures.

[0026] As used herein, the term "distal" refers to the end of the device farthest from the medical professional when introduced into a patient, and the term "proximal" refers to the end of the device closest to the medical professional when introduced into a patient.

[0027] As used herein, the term "tissue retraction" or "retraction" refers to the ability to control the position of tissue during a dissection procedure. For example, "retraction" can allow a stripped portion of target tissue to be secured and lifted away from the cutting plane to improve visualization of the remaining (i.e., unstripped) target tissue while also applying tension to the target tissue for more precise manipulation of the cutting element.

[0028] As used herein, the term "target tissue" refers to an unhealthy, diseased (i.e., cancerous, precancerous, etc.) or other undesirable portion of tissue. "Target tissue" may also include tissue that is suspected to be unhealthy or diseased, but which requires surgical removal to verify its disease state by biopsy. It should be understood that surgical removal of "target tissue" typically involves removing a portion of surrounding healthy tissue along the edges of the "target tissue" to ensure complete removal and minimize the possibility of the remaining or removed "target tissue" cells metastasizing to other parts of the body.

[0029] In one embodiment, the present disclosure provides a tissue retraction device that improves visibility and accessibility of target tissue during a dissection procedure by retracting and securing a dissected portion of target tissue, including without occupying and / or obstructing a working channel of an endoscope. Figures 1A-1B As shown, in one embodiment, the tissue retractor of the present disclosure may include an elongated flexible element 110 (e.g., a spine) including a proximal end 112 configured to engage a first target tissue portion, a distal end 114 configured to engage a second target tissue portion, a first surface 116 (i.e., a top or upper surface), and a second surface 118 (i.e., a bottom or lower surface). A plurality of guide members 130 may be disposed along the length of the elongated flexible element 110. Although Figures 1A-1B The guide members 130 are generally evenly spaced along the second surface 118 of the elongated flexible element 110, but it should be understood that the guide members can be provided on either the first surface 116 and / or the second surface 118 in a uniform or non-uniform pattern. Alternatively, the guide members can be tangential or coplanar with either the first surface 116 or the second surface 118 of the elongated flexible element 110. Additionally, although Figures 1A-1BThe elongated flexible element 110 is shown to include five guide members 130, but it should be understood that the number of guide members 130 may be less than five (i.e., four or less) or more than five (i.e., six or more). Although shown as circular, the cross-section of the guide members may be any of a variety of shapes, such as semicircular, oval, square, rectangular, etc. The elongated flexible element may include various lengths (e.g., approximately 6.0 inches, approximately 5.0 inches, approximately 4.0 inches, approximately 3.0 inches, approximately 2.75 inches, approximately 2.0 inches, approximately 1.5 inches, approximately 1.0 inches). Each guide member 130 may define a lumen 132 extending therethrough. In one embodiment, the end of the most distal guide member 130 (i.e., the guide member closest to the distal end 114 of the elongated flexible element 110) may include a cap 134. In one embodiment, the elongated flexible element 110 may include parallel elements or wires 126a, 126b connected to each other by a plurality of guide members 130. The tissue retractor may further include a control wire 140 (eg, a restraining mandrel) configured to be slidably received by the corresponding lumen 132 of each guide member 130 along the longitudinal axis of the elongated flexible element 110. Figure 1A , when the control wire 140 is disposed within the corresponding lumen 132 of each guide member 130, the elongated flexible element 110 remains in the first configuration (ie, the constrained, restricted, storage, or delivery configuration). Figure 1B When the control wire 140 is not disposed within (ie, removed from) the corresponding lumen 132 of each guide member 130 , the elongated flexible element 110 moves to a second configuration (ie, a relaxed, free, or deployed configuration).

[0030] In the first configuration, the elongated flexible element 110 has a flat or planar configuration such that substantially all of the second surface 118 is placed in contact with the tissue surface. In one embodiment, the elongated flexible element 110 can have a width and a thickness, wherein the width exceeds the thickness, such that the elongated flexible element 110 resists a tendency to roll or twist during a dissection procedure. For example, the elongated flexible element can have a width (e.g., approximately 0.070 inches, approximately 0.065 inches, approximately 0.060 inches, approximately 0.055 inches, approximately 0.050 inches) that is greater than the thickness (e.g., approximately 0.040 inches, approximately 0.035 inches, approximately 0.030 inches, approximately 0.025 inches, approximately 0.020 inches), and in some cases, the width can be approximately twice the thickness. The elongated flexible element 110 can be made of, for example, a variety of elastic, biocompatible materials, including metals and metal alloys, such as platinum, tungsten, titanium, stainless steel, nickel, and nickel-titanium alloys (e.g., Nitinol); polymers, such as acrylate-based polymers, polyurethane-based polymers, polynorbornene-based polymers, and polylactide-based polymers, and any combination thereof.

[0031] It will be appreciated that, when in the constrained configuration, the "force" stored within such material allows the elongated flexible element 110 to apply and maintain a constant upward lifting / retraction pressure against the tissue in which it is embedded. The natural tendency of the elongated flexible element 110 to move (i.e., return) from the flat or planar shape of the first configuration to the curved (e.g., rounded or hemispherical) shape of the second configuration allows the peeled portion of the target tissue to be lifted or elevated above the cutting plane, making the unpeeled target tissue portion more easily visualized and more effectively resectable. The shape of the second configuration can be controlled during manufacture of the elongated flexible element 110 to impart or set a desired memory for the elongated flexible element material to assume in a relaxed, unconstrained position.

[0032] Reference Figures 2A-2D The proximal and distal ends 112, 114 of the elongated flexible element 110 may include various anchor configurations including, by way of non-limiting example, wire pins or tines ( Figure 2A ), wire forks, fingers or hooks ( Figure 2B ), wire end ( Figure 2C ) and / or rings, clamps or barbs ( Figure 2D ) to prevent the elongated flexible element 110 from dislodging from the tissue surface prior to completion of the dissection procedure. Additionally or alternatively, the proximal end 112 and the distal end 114 may advantageously include sharpened or pointed tips to facilitate tissue penetration. In one embodiment, these (and other) wire anchor configurations may include a shape memory material (e.g., Nitinol) that is heat-set to point downward when deployed, but can be constrained in a straight position within a delivery catheter prior to deployment. When embedded within the target tissue, the proximal end 112 and the distal end 114 apply upward (e.g., lifting) and outward (e.g., longitudinal) retractive forces to the target tissue while simultaneously pushing or pressing the second surface 118 of the elongated flexible element 110 downward against the target tissue surface.

[0033] Reference Figure 3 In one embodiment, one or more stabilizers 325 (e.g., hooks, barbs, etc.) may be disposed along and extend outwardly from one or more of the guide members 330 attached to the second surface 318 of the elongated flexible element 310. Pressure applied against the target tissue along the second surface 318 of the elongated flexible element 310 allows such stabilizers 325 to engage an additional portion of the target tissue between the proximal end 312 and the distal end 314. The additional tissue engagement provided by the stabilizers 325 may also prevent or minimize any tendency of the elongated flexible element 310 to roll or twist during the dissection procedure while also providing additional retraction force to the target tissue. Additionally or alternatively, the stabilizers 325 may be attached to the bottom surface of the parallel wires when the guide members are placed on top of the parallel wires.

[0034] Reference Figures 4A-4B In one embodiment, the portions of the parallel wires 426a, 426b between the one or more guide members 430 may be flared or arched after deployment of the elongated flexible element 410 to provide one or more regions of increased surface area to provide additional stability (e.g., resistance to rolling or twisting). For example, one or more portions of the parallel wires 426a, 426b may be heat set during production so that their posture when constrained is straight ( Figure 4A ) and arches outwards upon leaving the delivery tube ( Figure 4B ).

[0035] Reference Figure 5 In one embodiment, the present disclosure can include a delivery system having an elongated flexible member 510 slidably disposed in a first (i.e., constrained) configuration within a lumen 556 of a delivery catheter 550 (e.g., an outer cannula, a constraining sheath, etc.). A control wire 540 can extend through the lumen 556 of the delivery catheter 550 such that a proximal end (not shown) of the control wire 540 extends beyond a proximal end (not shown) of the delivery catheter 550.

[0036] Reference Figure 6A In use and by way of example, the endoscope 660 can be advanced into a body passageway such that the distal end 664 of the endoscope 660 is positioned adjacent the target tissue 72. A delivery system (such as Figure 5 The catheter in the delivery catheter 650 may then be advanced through the working channel 666 of the endoscope 660 such that the distal end 654 of the delivery catheter 650 is positioned over the first portion of the target tissue 72. The proximal end of the control wire may then be advanced distally such that the distal end 614 of the elongated flexible element 610 moves past the distal end 654 of the delivery catheter 650. It should be understood that the cap 634 ( Figure 6B ) provides a surface against which the control wire 640 can apply such distal force. The control wire 640 can be further advanced distally to embed the distal end 614 of the elongated flexible element 610 within the first portion of the target tissue 72. Alternatively, the control wire can remain in place and the catheter or endoscope advanced to embed the anchor. In one embodiment, the distal end 614 can be moved from the constrained configuration to the deployed configuration upon exiting the delivery catheter 650. The deployed configuration can provide a larger (i.e., wider) surface area for increased engagement with the target tissue. Figure 6B When a distal force is applied (eg, maintained) to the elongated flexible element 610 via the control wire 640, the delivery catheter 650 can be retracted proximally such that the proximal end 612 of the elongated flexible element 610 moves past the distal end 654 of the delivery catheter 650. Figure 6C, the distal end 654 of the delivery catheter 650 can then be advanced distally such that a distal force is applied or exerted against the proximal end 612 of the elongated flexible element 610 to embed the proximal end 612 within the second portion of the target tissue 72. It should be understood that the distal force applied by the distal end 654 of the delivery catheter 650 against the proximal end 612 can cause the elongated flexible element 610 to bow or flex inwardly before (or during) the embedment of the proximal end 612 within the second portion of the target tissue 72. Upon removal of the distal force applied by the distal end 654 of the delivery catheter 650, the elongated flexible element 610 can return to an unflexed configuration such that the proximal and distal ends 612, 614 are further pressed and engaged into the respective first and second portions of the target tissue 72. Alternatively, sufficient distal pressure can be applied to the control wire itself to cause the elongated flexible element to bow sufficiently to embed the anchor without engaging the elongated flexible element with the distal end of the delivery catheter. Additionally or still alternatively, the anchor itself may be configured such that it can be self-seated or embedded with little or no distal pressure. Figure 6D , the control wire 640 can then be retracted proximally and removed from the corresponding lumen 632 of each guide member 630. As the control wire 640 is removed, the elongated flexible element 610 is further secured to the target tissue 72 due to the natural tendency of the elongated flexible element 610 to move from the first configuration to the second configuration, thereby applying an upward and outward force to the proximal end 612 and the distal end 614. Simultaneously, pressure can be generated to push or press the second surface 618 of the elongated flexible element 610 against the surface of the target tissue 72. It should also be understood that in certain surgical procedures, it may be preferable to embed one or both of the proximal end 612 and the distal end 614 into a portion of healthy (e.g., non-lesional) tissue outside of or beyond the edge of the target tissue to minimize the possibility of removing cancerous cells that may promote metastasis. In such cases, tissue can be retracted only from the side of the elongated flexible element having the anchor embedded in the tissue to be removed.

[0037] Reference Figures 7A-7CThe cutting element 768 can then be advanced through the working channel 766 of the endoscope 760 to dissect the target tissue 72 from the surrounding healthy tissue 70. As the target tissue 72 is dissected, the portion of the elongate flexible element 710 attached to the dissected tissue shifts from the first configuration to the second configuration, lifting and pulling the dissected target tissue 72 away from the cutting element 768 and the endoscope camera 769. Once the target tissue is fully dissected, the elongate flexible element 710 and attached target tissue 72 can be removed through the working channel 766 of the endoscope 760 with a suitable grasping element (not shown) for biopsy. Alternatively, the elongate flexible element 710 and attached target tissue 72 can be allowed to remain within the body passageway for removal by the body's natural processes. Importantly, the elongate flexible element 710 does not occupy the working channel 766 of the endoscope 760 during the dissection process, thereby allowing the medical professional to introduce and manipulate additional medical tools as needed for a given medical procedure.

[0038] Referring to Figures 8A-8B In one embodiment, the tissue retractor of the present disclosure can include an elongate flexible element 810 having a mesh structure that can be formed from various woven or interlaced shapes of polymer, metal, or alloy. The proximal end 812 and the distal end 814 of the elongate flexible element 810 can include a plurality of free wire ends 824 (e.g., wire tines) configured to engage a first target tissue portion and a second target tissue portion in a "Velcro-like" manner. In one embodiment, the surface of the elongate flexible element 810 can include one or more guide members configured to receive a control wire (not shown). As above, the control wire can maintain the elongate flexible element 810 in a first (i.e., constrained) configuration when disposed within a central lumen (not shown) and allow the elongate flexible element to return to a second (i.e., relaxed) configuration when not disposed within the central lumen. Figure 8A Figure 8B The elongate flexible element 810 can be deployed into and over the target tissue with a delivery catheter and endoscope, as discussed above.

[0039] Referring to Figure 9 In one embodiment, one or more elongate flexible elements 910a, 910b can be deployed onto the target tissue 72 to provide multiple planes of tissue retraction. For example, a first elongate flexible element 910a can be deployed along a first plane of the target tissue 72, and a second elongate flexible element 910b can be deployed along a second plane of the target tissue 72, above and perpendicular to the first elongate flexible element 910a. It should be appreciated that the multiple planes of retraction achieved with multiple elongate flexible elements can provide the required tissue retraction force to safely and effectively dissect a large and / or irregularly shaped target tissue, or to dissect tissue within and around delicate anatomical structures.

[0040] Referring to​ Figure 10A In one embodiment, a tissue retractor of the present disclosure can include an elongated flexible element 1010 (as discussed above) and further comprising a first arm 1028a and a second arm 1028b (e.g., a strip, a flap, a leg, etc.) extending radially outward from a central portion 1013 of the elongated flexible element 1010. An end 1029a of the first arm 1028a can be configured to engage a third target tissue portion, and an end 1029b of the second arm 1028b can be configured to engage a fourth target tissue portion. A plurality of guide members 1030 can be disposed along a first surface 1016 (e.g., a top surface) of the first arm 1028a and the second arm 1028b. Each guide member 1030 can define a lumen 1032 extending therethrough. In one embodiment, the distal-most guide member 1030 (i.e., the guide member closest to the ends 1029a, 1029b) on each of the first and second arms 1028a, 1028b may include a cap 1034 to provide a surface against which the control wire can apply distal force. To this end, the tissue retractor may further include first and second control wires 1040a, 1040b configured to be slidably received by respective lumens 1032 of each guide member 1030 disposed along the first surface 1016 of the first and second arms 1028a, 1028b. For example, the first control wire 1040a may extend along the first surface 1016 of the proximal portion 1017 of the elongated flexible element 1010 and turn approximately 90 degrees at the central portion 1013 to be slidably received by the lumen 1032 of the guide member 1030 on the first arm 1028a. The second control wire 1040b can extend parallel to the first control wire 1040a along the first surface 1016 of the proximal portion 1017 of the slender flexible element 1010 and turn approximately 90 degrees at the central portion 1013 to be slidably received by the lumen 1032 of the guide member 1030 on the second arm 1028b. Although not shown, an additional control wire (i.e., a third control wire) can be disposed along the second surface 1018 (e.g., the bottom surface) of the slender flexible element 1010, for example, as shown. Figures 1A-1B When the first control wire 1040a and the second control wire 1040b are disposed within the corresponding lumen 1032 of each guide member 1030, the first arm 1028a and the second arm 1028b are maintained in the first (ie, constrained) configuration. Figure 10B , when the first and second control wires 1040a, 1040b are not disposed within (i.e., removed from) the respective lumens 1032 of the guide members 1030, the first and second arms 1028a, 1028b move to a second (i.e., relaxed) configuration. It will be appreciated that when in the constrained configuration, the "force" stored within such materials can allow the elongated flexible element 1010 to exert and maintain a constant upward lifting / retracting pressure along multiple planes of the target tissue in which it is embedded.

[0041] Figure 10B The tissue retractor shown is slidably disposed within the lumen of a delivery catheter as discussed above. In one embodiment, the elongated flexible element 1010 portion of the tissue retractor can be deployed at the target tissue site by following the steps outlined above. The first control wire 1040a and the second control wire 1040b can then be advanced distally to force the first arm 1028a and the second arm 1028b outward to a flat configuration ( Figure 10A ), such that the ends 1029a, 1029b engage the respective third and fourth tissue portions. It should be understood that the arms of the elongated flexible element can be formed in any variety of shapes, and the ends 1029a, 1029b of each arm can include any manner of tissue anchor configuration, including Figures 2A-2D shown.

[0042] Reference Figure 11A In another embodiment, the tissue retractor of the present disclosure may include an elongated flexible element 1110, such as Figure 1AAs shown, it also includes a first arm 1128a and a second arm 1128b extending radially from a distal portion 1115 of the elongated flexible member 1110, and a third arm 1128c and a fourth arm 1128d extending radially from a proximal portion 1117 of the elongated flexible member 1110. An end 1129a of the first arm 1128a can be configured to engage a third target tissue portion, an end 1129b of the second arm 1128b can be configured to engage a fourth target tissue portion, an end 1129c of the third arm 1128c can be configured to engage a fifth target tissue portion, and an end 1129d of the fourth arm 1128d can be configured to engage a sixth target tissue portion. A plurality of guide members 1130 can be disposed along the first surface 1118 (i.e., top surface) of the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d. Each guide member 1130 can define a lumen extending therethrough. In one embodiment, the distal most guide member 1130 on each of the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d (i.e., the guide member closest to the ends 1129a-d) can include an end cap to provide a surface against which a control wire can apply a distal force. To this end, the tissue retractor can also include a first control wire 1140a, a second control wire 1140b, and a third control wire 1140c configured to be slidably received by the respective lumens of each guide member 1130 disposed along the first surface 1118 of the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d. For example, the first control wire 1140a can extend along the first surface 1118 of the elongated flexible member 1110 and include a bifurcated or split end configured to be slidably received by the lumens of the guide members 1130 on the first arm 1128a and the second arm 1128b. Alternatively, the elongated flexible member 1110, the first arm 1128a, and the second arm 1128b can include separate / distinct control wires (not shown) to allow independent deployment. The second control wire 1140b can extend parallel to a portion of the first control wire 1140a and turn 90 degrees or more at the proximal portion 1117 of the elongated flexible member 1110 to be slidably received by the lumens of the guide members 1130 on the third arm 1128c. The third control wire 1140c can extend parallel to a portion of the first control wire 1140a and turn 90 degrees or more at the proximal portion 1117 of the elongated flexible member 1110 to be slidably received by the lumens of the guide members 1130 on the fourth arm 1128d. Although not shown, an additional control wire (i.e., a fourth control wire) can be disposed along the second surface (i.e., bottom surface) of the elongated flexible member 1110, for example, Figures 1A-1B as outlined above.

[0043] When the first control wire 1140a, the second control wire 1140b, and the third control wire 1140c are disposed within the corresponding lumens of each guide member 1130, the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d are maintained in the first (ie, constrained) configuration. Figure 11B , when the first control wire 1140a, the second control wire 1140b, and the third control wire 1140c (not shown) are not disposed within (i.e., moved out of) the corresponding lumen of each guide member 1130, the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d move to a second (i.e., relaxed) configuration. Additionally or alternatively, the distal arm and the proximal arm along the longitudinal axis can be folded into the second configuration when unconstrained similarly to the other arms. Figure 11C In one embodiment, the first arm 1128a, the second arm 1128b, the third arm 1128c, and the fourth arm 1128d can be formed of a sufficiently flexible or deformable material that can collapse inwardly along the elongated flexible element 1110 when constrained within the lumen of a delivery catheter. It will be appreciated that when in the constrained configuration, the "force" stored within such material can allow the elongated flexible element 1110 to apply and maintain a constant upward lifting / retracting pressure along multiple planes of the target tissue in which it is embedded.

[0044] Figure 11C The tissue retractor shown is slidably disposed within the lumen of a delivery catheter as discussed above. In one embodiment, the elongated flexible element 1110 portion of the tissue retractor can be deployed on the target tissue by following the steps outlined above. The first, second, and third control wires (not shown) can then be advanced distally to force the first, second, third, and fourth arms 1128a, 1128b, 1128c, and 1128d outward to an expanded configuration ( Figure 11A ), such that the ends 1129a-d engage the respective third, fourth, fifth, and sixth tissue portions. It should be understood that the ends 1129a-d of each arm may include any manner of tissue anchor configuration, including, for example, Figures 2A-2D shown.

[0045] Reference Figures 12A-12B In one embodiment, the tissue retractor of the present disclosure may include a device configured to be in a first (ie, constrained) configuration ( Figure 12B ) and the second (i.e., relaxed, rolled, or collapsed) morphology ( Figure 12A ) between the sheet 1210 of shape memory material. A plurality of tissue anchors 1224 can be provided around the perimeter 1210a of the sheet 1210. Although Figures 12A-12BThe tissue anchors 1224 are generally evenly spaced along the perimeter 1210a of the sheet 1210, it being understood that the tissue anchors may be arranged in a uniform or non-uniform pattern around the perimeter 1210a. It will be understood that the "force" stored in such shape memory material may allow the sheet 1210 to apply and maintain a constant upward lifting / retracting pressure along multiple planes of the target tissue in which it is embedded. Figure 12A As shown, the sheet 1210 can be delivered rolled into a first relaxed, cylindrical configuration and slidably positioned and constrained within the lumen of a delivery catheter (not shown), as shown. Figures 1A-1B The sheet 1210 can be advanced distally over the distal end of the delivery catheter and unfolded to present a Figure 12B 1224 into a second, constrained configuration, thereby allowing tissue anchors 1224 to engage portions of the target tissue. Additionally or alternatively, a medical device (i.e., a biopsy forceps, etc.) may be advanced through the delivery catheter to precisely position sheet 1210 and apply sufficient pressure to engage at least some of tissue anchors 1224 within the target tissue. Once sheet 1210 is in its second configuration ( Figure 12B ) is fixed to the target tissue, the central portion of the sheet 1210 can contact (i.e., strike, hit, tap, etc.) the medical device to stimulate the sheet 1210 to attempt to return to the first shape memory configuration ( Figure 12A ), thereby applying upward lifting / retracting pressure to the target tissue, as discussed above. It should be understood that the tissue retractors described herein may include arms and tissue anchors of any number, shape, size, and / or orientation.

[0046] All of the devices and / or methods disclosed and claimed herein can be made and executed in accordance with the present disclosure without undue experimentation. Although the devices and methods of the present disclosure have been described in terms of preferred embodiments, it will be apparent to those skilled in the art that modifications may be made to the devices and / or methods, as well as to the steps or order of steps of the methods, described herein without departing from the concept, spirit, and scope of the present disclosure. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the present disclosure as defined by the appended claims.

Claims

1. A tissue retractor comprising: An elongated flexible member configured to be embedded in target tissue, comprising: configured to engage the proximal end of the first target tissue portion, a distal end configured to engage a second target tissue portion; the proximal end and the distal end comprising one or more tissue anchors to prevent the elongated flexible member from detaching from a tissue surface, wherein the one or more tissue anchors extend from the proximal end and the distal end of the elongated flexible member; at least one guide member attached to the elongated flexible element, wherein the at least one guide member defines a lumen extending therethrough; and a control wire configured to be slidably received within the lumen of the at least one guide member; wherein the elongated flexible element moves between a first configuration when the control wire is disposed within the lumen of the at least one guide member and a second configuration when the control wire is not disposed within the lumen of the at least one guide member; and wherein the proximal end and the distal end are configured to apply an upward and outward retraction force to tissue.

2. The tissue retractor of claim 1, wherein the at least one guide member comprises a plurality of guide members attached along the length of the elongated flexible element.

3. The tissue retractor of claim 1 or 2, wherein an end of the at least one guide member comprises a cap.

4. The tissue retractor of claim 1, wherein the elongated flexible element is flat when in the first configuration.

5. The tissue retractor of claim 1 or 4, wherein the elongated flexible element is curved along a longitudinal axis when in the second configuration.

6. The tissue retractor of claim 1, wherein the elongated flexible element comprises a woven mesh.

7. The tissue retractor of claim 1, wherein the elongated flexible elements comprise parallel elements.

8. The tissue retractor of claim 7, wherein the parallel elements are attached to each other by the at least one guide member.

9. The tissue retractor of claim 8, wherein the control wire passes between the parallel elements when disposed within the lumen of the at least one guide member.

10. The tissue retractor of any one of claims 1, 4, or 6 to 9, wherein the one or more tissue anchors are selected from the group consisting of: tines, prongs, hooks, fingers, barbs, loops, and clamps.

11. The tissue retractor of any one of claims 1, 4, or 6 to 9, further comprising at least one stabilizer attached to the elongate flexible element.

12. The tissue retractor of claim 11, wherein the stabilizer comprises one or more tissue engaging elements selected from the group consisting of a hook or a barb.

13. The tissue retractor of any one of claims 7 to 9, wherein a portion of the parallel elements are configured to bow outwardly from the longitudinal axis of the elongate flexible element.

14. The tissue retractor of any one of claims 1, 2, 4, or 6 to 9, wherein the elongated flexible element comprises a polymer selected from the group consisting of acrylate-based polymers, polyurethane-based polymers, polynorbornene-based polymers, and polylactide-based polymers.

15. The tissue retractor of any one of claims 1, 2, 4, or 6 to 9, wherein the elongated flexible element comprises a metal or metal alloy selected from the group consisting of platinum, tungsten, titanium, stainless steel, nickel, and nickel-titanium alloy.

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