Endoscopic tissue resection device
By designing an endoscopic tissue resection device, and combining an innovative configuration of a cap, snare sheath, and spring wire, the contradiction between the flexibility and grip of the snare is resolved, achieving precise and reliable tissue resection without occupying the endoscope channel, and providing greater suction and instrument usage space.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- UNIVERSITY HOSPITALS OF CLEVELAND CLEVELAND
- Filing Date
- 2022-01-20
- Publication Date
- 2026-05-15
AI Technical Summary
Existing endoscopic snares have a trade-off between flexibility and tissue gripping ability, resulting in inaccurate, ineffective, and difficult-to-reproduce tissue resections, and the inability to use auxiliary devices to assist in resection.
An endoscopic tissue resection device has been designed, including a cap, a snare sheath, a snare, and a spring wire. The device achieves reliable and repeatable tissue resection through the cavity of the cap, the snare actuation cable, and the foldable snare wire, combined with the deflection and bending of the spring wire.
It achieves more reliable, repeatable and effective tissue removal, ensuring precise capture and removal of tissue without occupying the internal channel of the endoscope, and providing greater suction and instrument usage space.
Smart Images
Figure CN116916837B_ABST
Abstract
Description
[0001] Citation of relevant applications
[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 140,013, filed January 21, 2021, which is incorporated herein by reference. Technical Field
[0003] The present invention generally relates to an apparatus for endoscopic tissue resection within a lumen, and more specifically to an apparatus for endoscopic tissue resection within a lumen comprising a cap, a snare sheath, a snare, and a spring wire. Background Technology
[0004] Endoscopic resection of tissue within the lumen is a challenging procedure.
[0005] Endoscopic snares are commonly used during colonoscopies and upper gastrointestinal endoscopy to perform biopsies and remove polyps or tissue for tumor evaluation. Commercially available endoscopic snares are used through the working channel of the endoscope. The snare is a loop of metal wire within a retractable outer sheath. When deployed, the snare forms a loop and positions itself around the tissue of interest, then closes to encircle, capture, and cut the surrounding tissue. If the sample is small enough, it can be removed using suction through the same working channel of the endoscope. Larger samples are captured by the endoscopic mesh and removed with the endoscope.
[0006] The snare wire must be flexible so that it can retract into a sheath to grip the tissue. Paradoxically, the more flexible the snare, the more difficult it is to engage the tissue. The snare often slips off the tissue.
[0007] Therefore, precise, effective, and repeatable tissue resection is challenging or impossible in some anatomical locations. Because the snare sheath occupies the only passage within the endoscope, auxiliary devices cannot be used to assist tissue resection. Distal endoscopic attachments, also known as “distal cap attachments” or “caps,” can be combined with the snare. The cap allows the use of suction to retract the tissue. However, positioning the snare within the cap remains a technical challenge.
[0008] There is a need for a device that can perform effective, precise, and repeatable endoscopic tissue resection. Summary of the Invention
[0009] An endoscopic tissue resection device configured to be attached to the distal end of an endoscope is disclosed. The device includes a cap, a snare sheath, a snare, and a spring wire.
[0010] The cap includes a cap body, a proximal end, a proximal opening, a distal end, and a distal opening. The cap body defines a cavity for tissue retraction and has an inner periphery.
[0011] The snare sheath includes a proximal end, a distal end, and a snare sheath body located between the proximal and distal ends. The distal end of the snare sheath is fixed to the cap body along the inner periphery of the cap body.
[0012] The snare includes a snare actuation cable and a foldable snare wire.
[0013] The snare actuation cable includes a proximal end, a distal end, and snare actuation cable bodies located at the proximal and distal ends, disposed within a snare sheath, and configured to translate proximally and distally within the snare sheath.
[0014] The foldable snare wire includes a base, an opposite vertex, and two opposing wire portions extending between the base and the vertex, disposed within a cavity of a cap, and reversibly foldable from an expanded state to a folded state. The base of the foldable snare wire is attached to the snare actuation cable at or near the distal end of the snare actuation cable.
[0015] The foldable snare wire is configured to retract from the cavity of the cap into the snare sheath by translating the snare actuation cable proximally within the snare sheath. The foldable snare wire reversibly folds from an expanded state to a folded state during retraction, and is advanced from the snare sheath into the cavity of the cap by translating the snare actuation cable distally within the snare sheath. The foldable snare wire reversibly expands to an expanded state during advancement.
[0016] The spring wire is disposed within the cavity of the cap and includes a proximal end, a distal end, and a flexible portion located between the proximal and distal ends. The proximal end of the spring wire is attached to the cap body at or near the proximal end of the cap. The distal end of the spring wire is attached to the apex of the foldable snare wire.
[0017] The spring wire can reversibly deflect from a rest state to a deflection state. When the foldable snare wire is positioned within the cavity of the cap, the spring wire is at rest. When the foldable snare wire retracts into the snare sheath, the spring wire deflects to the deflection state. In the rest state, the spring wire orients and stabilizes the apex of the foldable snare wire within the cap, at or near the distal opening of the cap, opposite the distal end of the snare sheath, such that the two opposing wire portions of the foldable snare wire are positioned opposite the distal opening of the cap. During deflection, the spring wire bends along an arc-shaped path into the snare sheath.
[0018] The distal end of the snare sheath is recessed into the cavity of the cap relative to the distal end of the spring wire, allowing the spring wire to bend along an arc-shaped path.
[0019] In some embodiments, the cap has an outer diameter of 0.5 to 1.5 cm.
[0020] In some embodiments, the cavity of the cap has an internal depth of 0.5 cm to 1.5 cm.
[0021] In some embodiments, the cavity of the cap has an inner diameter, the spring wire has a length, and the inner diameter of the cavity of the cap is greater than the length of the spring wire.
[0022] In some embodiments, the distal end of the hood has a sloping profile.
[0023] In some embodiments, the distal end of the cap includes a lip located within the cavity of the cap for retaining the foldable snare wire within the cavity of the cap.
[0024] In some embodiments, the two opposing wire portions of the foldable snare wire have an approximately hexagonal, circular, or elliptical shape in the expanded state.
[0025] In some embodiments, the distal opening of the cap has an inner circumference having a diameter, and the foldable snare wire in its expanded state is sufficiently close to the inner circumference of the distal opening of the cap such that any gap between the two opposing wire portions of the foldable snare wire and the inner circumference of the distal opening of the cap is no greater than 10%, 8%, 6%, 4%, or 2% of the diameter of the inner circumference of the distal opening of the cap.
[0026] In some embodiments, the distal opening of the cap has an inner circumference, and the foldable snare wire in an expanded state is sufficiently close to the inner circumference of the distal opening of the cap such that any gap between the two opposing wire portions of the foldable snare wire and the inner circumference of the distal opening of the cap is no greater than 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm.
[0027] In some embodiments, the hood has a distal edge at its distal end, the cavity of the hood has an internal depth, and the foldable snare wire in its expanded state is fully flush with the distal edge of the hood at its distal end, such that any gap between the two opposing wire portions of the foldable snare wire and the distal edge of the hood at its distal end does not exceed 20%, 16%, 12%, 8%, or 4% of the internal depth of the cavity of the hood.
[0028] In some embodiments, the hood has a distal edge at its distal end, the hood has an axis extending from the proximal end of the hood to the distal end of the hood, and the foldable snare wire in an expanded state is fully flush with the distal edge of the hood's distal end, such that any gap between the two opposing wire portions of the foldable snare wire and the distal edge of the hood's distal end, measured along the axis, does not exceed 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm.
[0029] In some embodiments, the snare sheath has an axis extending from its proximal end to its distal end, and the foldable snare wire is shaped to deflect from the axis as the foldable snare wire is advanced from the distal end of the snare sheath.
[0030] In some embodiments, the device further includes a blade disposed in a cavity of the cap adjacent to the distal end of the snare sheath. Attached Figure Description
[0031] These and other features, aspects and advantages of this disclosure can be better understood when the following detailed description is read in conjunction with the accompanying drawings.
[0032] Figure 1 This is a top view of one embodiment of an endoscopic tissue resection device, which includes a cap, a snare sheath, a snare and a spring wire, and a snare actuator handle attached to the device. A portion of the snare sheath and the snare are in a coiled configuration. As shown, the device terminates proximally at the snare actuator handle and distally at the cap.
[0033] Figure 2 yes Figure 1 Side view of the cap of an endoscopic tissue resection device.
[0034] Figure 3 yes Figure 1 A front view of the cap of an endoscopic tissue resection device.
[0035] Figure 4 yes Figure 1 Rear view of the cap of the endoscopic tissue resection device.
[0036] Figure 5 yes Figure 1 A top view of the snare sheath and distal portion of the snare of an endoscopic tissue resection device, wherein the foldable snare wire is fully extended from the snare sheath and in an expanded state.
[0037] Figure 6 yes Figure 1 A side view of the snare sheath and distal portion of the snare of an endoscopic tissue resection device, wherein the foldable snare wire is partially retracted into the snare sheath.
[0038] Figure 7 yes Figure 1 A side view of the spring wire of an endoscopic tissue resection device, wherein the spring wire is straight in its resting state.
[0039] Figure 8 yes Figure 1A frontal perspective view of the endoscopic tissue resection device's cap, snare sheath, distal portion of the snare, and spring wire, showing the foldable snare wire fully extended from the snare sheath, in an expanded state, and the spring wire at rest. Based on the orientation and stability provided by the spring wire and two opposing wire portions of the foldable snare wire positioned juxtaposed with the distal opening of the cap, the foldable snare wire is tightly aligned with the inner circumference of the distal opening of the cap and flush with the distal edge of the cap. The fully opened foldable snare wire is seen aligned with the periphery of the distal cap edge. The spring wire is seen longitudinally aligned with the cap wall.
[0040] Figure 9 yes Figure 1 A frontal perspective view of the cap, snare sheath, and distal portion of the snare of an endoscopic tissue resection device, as well as the spring wire, showing the foldable snare wire partially retracted into the snare sheath, folding from an expanded state to a folded state, and the spring wire deflecting from a stationary state to a deflected state. The distal edge of the partially closed foldable snare wire can be seen narrowing away from the cap. The spring wire begins to flex away from the cap wall.
[0041] Figure 10 yes Figure 1 A frontal perspective view of the cap, snare sheath, distal portion of the snare, and spring wire of an endoscopic tissue resection device, wherein the foldable snare wire is fully retracted into the snare sheath, the foldable snare wire is in a folded state, and the spring wire is in a deflected state. The fully closed foldable snare wire is retracted into the snare sheath. The spring wire flexes across the diameter of the cap.
[0042] Figure 11 Is it like this? Figure 8 The hood, snare sheath, and distal portion of the snare shown are illustrated in a side view, along with the spring wire.
[0043] Figure 12 Is it like this? Figure 9 The hood, snare sheath, and distal portion of the snare shown are illustrated in a side view, along with the spring wire.
[0044] Figure 13 Is it like this? Figure 10 The hood, snare sheath, and distal portion of the snare shown are illustrated in a side view, along with the spring wire.
[0045] Figure 14 Is it like this? Figure 8 The hood, snare sheath, and distal portion of the snare shown are illustrated in a side view, with the tissue retracted into the hood and surrounded by the snare's foldable snare wire.
[0046] Figure 15 Is it like this? Figure 9 The diagram shows a side view of the hood, snare sheath, and distal portion of the snare, as well as the spring wire, with the tissue retracted into the hood and being cut off by the snare's foldable snare wire.
[0047] Figure 16 Is it like this? Figure 10 The hood, snare sheath, and distal portion of the snare shown are illustrated in a side view of the spring wire, with the tissue retracted into the hood and cut off by the foldable snare wire of the snare.
[0048] Figure 17 It includes the lips. Figure 1 Side view of the cap of an endoscopic tissue resection device.
[0049] Figure 18 yes Figure 1 A frontal perspective view of the cap, snare sheath, and distal portion of the snare of an endoscopic tissue resection device, and the spring wire, wherein the blade is positioned in the cavity of the cap adjacent to the distal end of the snare sheath.
[0050] Figure 19 yes Figure 1 A top view of the snare sheath and distal portion of the snare and the distal portion of the spring wire of an endoscopic tissue resection device, wherein the foldable snare wire is fully extended from the snare sheath and in an expanded state, and the distal end of the spring wire is attached to the apex of the snare at a welded location.
[0051] Figure 20 yes Figure 1 A side view of another embodiment of the spring wire of the endoscopic tissue resection device, wherein the spring wire has been folded over itself.
[0052] Figure 21 yes Figure 1 A top view of the snare sheath and distal portion of the snare and the distal portion of the spring wire of the endoscopic tissue resection device, wherein the spring wire is folded over itself, the foldable snare wire is fully extended from the snare sheath and is in an expanded state, and the distal end of the spring wire is attached to the apex of the snare by placing the folded spring wire on the apex of the snare and securing the joint with a collar. Detailed Implementation
[0053] An endoscopic tissue resection device 100 configured to be attached to the distal end of an endoscope is disclosed. Figure 1 The endoscopic tissue resection device 100 includes a cap 102, a snare sheath 104, a snare 106, and a spring wire 108, which are configured to advantageously provide more reliable, reproducible, and effective tissue resection. Figure 1-16 ).
[0054] The hood 102 includes a hood body 110, a proximal end 112, a proximal opening 114, a distal end 116, and a distal opening 118. Figure 2-4 The cap body 110 defines a cavity 120 for tissue retraction and has an inner periphery 122.
[0055] The cap 102 may be made of transparent or translucent plastic or polymer material to provide endoscopic visualization while minimizing interference. The cap 102 may be made with a smooth surface to avoid harm to the patient.
[0056] The cap 102 is sized to allow it to attach to the distal end of the endoscope, tissue to be retracted into the cavity 120 of the cap 102, and spring wire 108 to flex along an arcuate path 124 within the cavity 120 of the cap 102 toward the distal end 126 of the snare sheath 104. To attach the cap 102 to the distal end of the endoscope and to retract tissue into the cavity 102, the cap 102 can be configured to have a range of outer diameter and internal depth. For example, the diameter of the cap 102 can be in the range of approximately 0.5–1.5 cm, and the depth of the cap 102 can vary in the range of approximately 0.5–1.5 cm. The cap 102 may also have a variable (e.g., adjustable) depth option, allowing for varying depths of tissue retraction. Regarding the bending of the spring wire 108 along the arcuate path 124 within the cavity 120 of the cap 102, the cap 102 must have a sufficiently large inner diameter to accommodate the bending of the spring wire 108 along the arcuate path 124 toward the distal end 126 of the snare sheath 104. This ensures that the inner surface 128 of the cap 102 does not impede the bending of the spring wire 108 along the arcuate path 124. This can be achieved by providing the cap 102 with a cavity 120 having an inner diameter greater than the length of the spring wire 108. Therefore, in some embodiments, the cap 102 has an outer diameter 130 of 0.5 to 1.5 cm. In some embodiments, the cavity 120 of the cap 102 has an internal depth 132 of 0.5 cm to 1.5 cm. In some embodiments, the cap 102 has a variable depth option. In some embodiments, the cavity 102 of the cap 102 has an inner diameter 134, the spring wire 108 has a length 136, and the inner diameter 134 of the cavity 120 of the cap 102 is greater than the length 136 of the spring wire 108.
[0057] The cap 102 is shaped to conform to the arcuate path 124 of the spring wire 108. Figure 11-13For example, compared to, for example, a vertical profile, a sloping profile at the distal end 116 of the cap 102 can advantageously better accommodate the arcuate path 124 of the spring wire 108. Thus, in some embodiments, the distal end 116 of the cap 102 has a sloping profile 138.
[0058] In some embodiments, the orientation and / or shape of the cap 102 may vary. For example, the orientation and / or shape of the cap 102 may be flat or beveled, circular or elliptical.
[0059] In some embodiments, the cap 102 may include a lip 140 located at the distal end 116 of the cap 102. Figure 14 This can facilitate better containment of the foldable snare wire 142 of the snare 106, for example, by physically preventing the foldable snare wire 142 in its expanded state 144 from passing distally through the distal opening 118 of the cap 102. Therefore, in some embodiments, the distal end 116 of the cap 102 includes a lip 140 located within the cavity 120 of the cap 102 for retaining the foldable snare wire 142 within the cavity 120 of the cap 102.
[0060] The snare sheath 104 includes a proximal end 146, a distal end 126, and a snare sheath body 148 located therebetween. Figure 1 , 5 -6, 11-13). The distal end 126 of the snare sheath 104 is secured to the cap body 110 along the inner periphery 122 of the cap body 110. The snare sheath 104 can be secured to the cap body 110, for example, by passing the snare sheath 104 through the snare sheath hole 150 of the cap 102 from the distal end 116 of the cap 102 to the cavity 120 of the cap 102, and then securing the snare sheath 104 to the cap body 110 along the inner periphery 122 of the cap body 110.
[0061] The snare sheath 104 may be made of polyethylene tubing or similar tubing. The snare sheath 104 may be made with a minimum inner and outer diameter to accommodate the snare actuation cable 152 and the snare 106, and a foldable snare wire 142, but with sufficient wall thickness to support tissue resection.
[0062] The snare 106 includes a snare actuation cable 152 and a foldable snare wire 142. Figure 1 , 5 -13)
[0063] The snare actuation cable 152 includes a proximal end 154, a distal end 156, and a snare actuation cable body 158 located therebetween. Figure 1 , Figure 11The snare actuation cable 152 is disposed within the snare sheath 104. The snare actuation cable 152 is configured to translate proximally and distally within the snare sheath 104.
[0064] The snare actuator cable 152 may be made of braided stainless steel or other similar commonly used wires.
[0065] The foldable snare wire 142 includes a base 160, a vertex 162 opposite to the base 160, and two opposing wire portions 164 extending therebetween. Figure 5-13 A foldable snare wire 142 is disposed within the cavity 120 of the cap 102. The foldable snare wire 142 can be reversibly folded from an expanded state 144 to a folded state 166. In the expanded state 144, the two opposing wire portions 164 of the foldable snare wire 142 have an open shape. This allows endoscopic visualization of the tissue between the two opposing wire portions 164 of the foldable snare wire 142 in the expanded state 144, i.e., visualization through the open shape formed by the two opposing wire portions 164. For example, the two opposing wire portions 164 of the foldable snare wire 142 may have an approximately hexagonal, circular, or elliptical shape in the expanded state 144. For example, the contact between the two opposing wire portions 164 of the foldable snare wire 142 and the inner surface 128 of the cap 102—which may cause some deformation of the wire—and / or, due to the flexibility of the two opposing wire portions 164 of the foldable snare wire 142—also causes some deformation of the shape. The two opposing wire portions 164 of the foldable snare wire 142 may have an approximate hexagonal, circular, or elliptical shape in the expanded state, rather than a strictly hexagonal, circular, or elliptical shape. The shape may also be pre-formed. The two opposing wire portions 164 of the foldable snare wire 142 may also have other shapes, such as other polygonal shapes that are approximately circular or elliptical. Therefore, in some embodiments, the two opposing wire portions 164 of the foldable snare wire 142 have an approximate hexagonal, circular, or elliptical shape in the expanded state 144. Moreover, in some examples, the two opposing wire portions 164 of the foldable snare wire 142 have a pre-formed shape.
[0066] The base 160 of the foldable snare wire 142 is attached to the snare actuation cable 152 at or near the distal end 156 of the snare actuation cable 152. Figure 5 ).
[0067] The foldable snare wire 142 is configured to retract from the cavity 120 of the cap 102 into the snare sheath 104 by translating the snare actuation cable 152 proximally within the snare sheath 104. Figure 8-13 The foldable snare wire 142 reversibly folds from the expanded state 144 to the folded state 166 upon retraction. The foldable snare wire 142 is also configured to be extended from the snare sheath 104 into the cavity 120 of the cap 104 by translating the snare actuation cable 152 distally within the snare sheath 104. The foldable snare wire 142 reversibly expands to the expanded state 144 upon extension.
[0068] The foldable snare wire 142 may be made of a material that allows the foldable snare wire 142 to repeatedly fold into the snare sheath 104 when retracted and expand when extended from the snare sheath 104, thereby maintaining its previous shape, such as generally hexagonal, circular, or elliptical. The foldable snare wire 142 may be made of, for example, braided stainless steel, nitinol, or other similar commonly used wire materials.
[0069] The spring wire 108 is disposed within the cavity 120 of the cap 102 and includes a proximal end 168, a distal end 170, and a flexible portion 172 located therebetween. Figure 7-13 20). The spring wire 108 can be, for example, a spring wire 108 that is substantially straight in its resting state. Figure 7 The proximal end 168 and the distal end 170 are the opposite ends of the spring wire 108. The spring wire 108 can also be, for example, a spring wire 108 like this (…). Figure 20 The spring wire 108 is folded in or near its middle part, such that the two ends of the spring wire 108 become the proximal end 168 of the spring wire 108 and the folded part becomes the distal end 170 of the spring wire 108.
[0070] The proximal end 168 of the spring wire 108 is attached to the cap body 110 at or near the proximal end 112 of the cap 102. Figure 8 , 11 The proximal end 168 of the spring wire 108 can be attached to the cap body 110, for example, by attaching the spring wire 108 to the cap 110 within the spring wire hole 174 inside the cap 110.
[0071] The distal end 170 of the spring wire 108 is attached to the apex 162 of the foldable snare wire 142. Figure 11-13(19, 21). This can be achieved by methods such as welding, bonding, using a collar, sheath, tube or other similar structure, or crimping. For example, for a spring wire 108 that is substantially straight in its resting state, the distal end 170 of the spring wire 108 can be welded to the apex 162 of the foldable snare wire 142 to form a welded portion 204. Moreover, for example, for a spring wire 108 that has been folded in or near its middle, the distal end 170 of the spring wire 108, i.e., the folded portion of the spring wire 108, can be attached to the apex 162 of the foldable snare by placing the folded spring wire 108 on the apex 162 and securing the joint with a collar 206 that is pressed tightly against the apex 162. Sheaths, tubes or other similar structures can be used instead of collars 206 or in addition to collars 206. The collar 206 or the sheath, tube or similar structure can be made of a material such as plastic, which provides insulation during the use of standard electrosurgical energy.
[0072] The spring wire 108 can reversibly deflect from a rest state 176 to a deflection state 178. When the foldable snare wire 142 is disposed within the cavity 120 of the cap 110, the spring wire 108 is in the rest state 176. When the foldable spring wire 108 is retracted into the snare sheath 104, the spring wire 108 deflects to the deflection state 178.
[0073] In the static state 176, the spring wire 108 orients and stabilizes the apex 162 of the foldable snare wire 142 within the cap 102, located at or near the distal opening 114 of the cap 102, opposite the distal end 126 of the snare sheath 104, such that the two opposing wire portions 164 of the foldable snare wire 142 are positioned juxtaposed with the distal opening 118 of the cap 102. Figure 8 , 11 As described above, in the expanded state 144, the two opposing wire portions 164 of the foldable snare wire 142 have an open shape, thereby allowing endoscopic visualization of the tissue between the two opposing wire portions 164 of the foldable snare wire 142 in the expanded state 144. By orienting and stabilizing the apex 162 of the foldable snare wire 142 in this manner, the spring wire 108 helps to position the foldable snare wire 142 to allow endoscopic visualization of the tissue beyond the distal opening 118 of the cap 102.
[0074] During deflection, the spring wire 108 bends along the arc path 124 to the snare sheath 104. Figure 9 , 1012, 13). The distal end 126 of the snare sheath 104 is recessed into the cavity 120 of the cap 102 relative to the distal end 170 of the spring wire 108 to allow the spring wire 108 to bend along the arcuate path 124.
[0075] The spring wire 108 can be made of spring material, such as nitinol, for example, nitinol with a diameter of 0.025 inches (0.635 mm), or plastic.
[0076] Near the point where the cap 102 is secured to the endoscope, the proximal end 168 of the spring wire 108 can be directly attached to the cap 102, opposite the distal end 126 of the snare sheath 104—for example, at approximately 180 degrees. The spring wire 108 can be disposed adjacent to the inner surface 128 of the cap 102 within the cavity 120 of the cap 102. The spring wire 108 can be oriented generally parallel to the longitudinal axis of the endoscope and the portion of the snare sheath 104 oriented along the endoscope. The distal end 170 of the spring wire 108 is located near the distal edge 180 of the distal end 116 of the cap 102. The distal end 170 of the spring wire 108 is attached to the apex 162 of the snare 106 in such a way that interference with the folding of the foldable snare wire 142 is avoided or minimized, and consequently interference with the closure of the two opposing wire portions 164 of the foldable snare wire 142 is avoided or minimized. The length of the spring wire 108 can be made proportional to the depth, diameter, and profile of the cap 102 to provide an arcuate path 124 for the spring wire 108 from the distal edge 180 of the distal end 116 of the cap 102 to the snare sheath 104.
[0077] The spring wire 108 has sufficient "spring" properties to achieve the following features without restricting the closing and reopening of the foldable snare wire 142.
[0078] The spring wire 108 contributes at least three distinct functions to the device 100. First, the spring wire 108 stabilizes the apex 162 of the foldable snare wire 142 at the distal end 116 of the cap 102, thereby ensuring that tissue retracted into the device 100 does not cause the foldable snare wire 142 to also retract into the cap 102. Second, the spring wire 108 ensures that the two opposing wire portions 164 of the foldable snare wire 142 open toward a position juxtaposed with the inner circumference of the distal opening 118 of the cap 102. Third, the spring wire 108 stably holds the foldable snare wire 142 against the tissue to be removed, thereby reducing the tissue's ability to slip across the foldable snare wire 142.
[0079] The endoscopic tissue resection device 100 can be operated as follows to complete tissue resection ( Figure 1 , 8 11, 14-16)
[0080] The cap 102 of the endoscopic tissue resection device 100 is attached to the distal end of the endoscope at the proximal end 112 of the cap 102. Figure 8 , Figure 11 For example, attachment can be achieved by using a compression fitting such as a compression belt or similar mechanism, or other similar low-profile accessories. The cavity 120 of the cap 102 is kept in fluid communication with the suction source, for example, through the internal endoscopic channel of the endoscope via the proximal opening 114 of the cap 102.
[0081] The snare actuator handle 182 is attached to the snare actuator cable 152. Figure 1 The snare sheath 104 terminates at its proximal end 146 at the snare actuator handle 182. Therefore, the snare actuator handle 182 allows control of the retraction and advance of the foldable snare wire 142 via the snare actuator cable 152, thereby facilitating manual opening and closing of the opposing wire portion 164 of the foldable snare wire 142 for tissue removal.
[0082] During operation of the endoscopic tissue resection device 100, the snare sheath 104 extends across the entire length of the endoscope and is located outside the endoscope.
[0083] The foldable snare wire 142 is positioned within the cavity 120 of the cap 102, such that the foldable snare wire 142 is in an expanded state 144 and the spring wire 108 is in a stationary state 166. Figure 8 , 11 As described above, in the resting state 166, the spring wire 108 orients and stabilizes the apex 162 of the foldable snare wire 142 within the cap 102, located at or near the distal opening 118 of the cap 102, opposite the distal end 126 of the snare sheath 104, such that the two opposing wire portions 164 of the foldable snare wire 142 are positioned juxtaposed with the distal opening 118 of the cap 102. Furthermore, as noted, the two opposing wire portions 164 of the foldable snare wire 142 may have a pre-formed approximately hexagonal, circular, or elliptical shape.
[0084] Based on the orientation and stability provided by the spring wire 108 and the two opposing wire portions 164 of the foldable snare wire 142, which is positioned juxtaposed with the distal opening 118 of the cap 102, the foldable snare wire 142 is closely aligned with the inner circumference of the distal opening 118 of the cap 102 and flush with the distal edge 180 of the distal end 116 of the cap 102.
[0085] Organization 200 retracts back into cap 102 through suction. Figure 14The foldable snare wire 142 is located adjacent to and flush with the inner circumference of the distal opening 118 of the hood 102, which ensures that when the tissue 200 is retracted into the hood 102 by suction, the tissue 200 becomes surrounded and captured by the foldable snare wire 142.
[0086] Then, the snare actuation cable 152 is translated proximally within the snare sheath 104 to retract the foldable snare wire 142 back into the snare sheath 104. Figure 15 This can be achieved, for example, by using a snare actuator handle 182 attached to a snare actuator cable 152.
[0087] When the foldable snare wire 142 retracts into the snare sheath 104, the foldable snare wire 142 folds to the folded state 166. Figure 16 When the foldable snare wire 142 is folded, the tissue 200 captured by the foldable snare wire 142 is removed.
[0088] Moreover, when the foldable snare wire 142 retracts into the snare sheath 104, the spring wire 108 bends along its arc path 124 to the snare sheath 104, thereby remaining attached to the apex 162 of the foldable snare wire 142.
[0089] After tissue 200 is removed, the foldable snare wire 142 can be pushed back into the cavity 120 of the cap 102 by translating the snare actuation cable 152 distally within the snare sheath 104. Figure 10 , Figure 13 This can be accomplished using a snare actuator handle 182 attached to the snare actuator cable 152. Upon extension, the foldable snare wire 142 expands to its expanded state 144, for example, returning to its pre-formed, approximately hexagonal, circular, or elliptical shape. The spring wire 108, still attached to the apex 162 of the foldable snare wire 108, returns to its rest state 166, and again orients and stabilizes the apex 162 of the foldable snare wire 142 within the cap 102, at or near the distal opening 118 of the cap 102, opposite the distal end 126 of the snare sheath 104, such that the two opposing wire portions 164 of the foldable snare wire 142 are positioned juxtaposed with the distal opening 118 of the cap 102. Based on the orientation and stability provided by the spring wire 108 and the two opposing wire portions 164 of the foldable snare wire 142 positioned juxtaposed with the distal opening 118 of the cap 102, the foldable snare wire 142 is again closely aligned with the inner circumference of the distal opening 118 of the cap 102 and flush with the distal edge 180 of the distal end 116 of the cap 102.
[0090] Furthermore, after tissue 200 is removed, the removed tissue 202 can be retrieved.
[0091] During the procedure, the entire endoscopic tissue resection device 100 is positioned outside the endoscope, thereby advantageously freeing up the internal endoscopic channel for use with additional instruments. The absence of devices within the internal endoscopic channel also advantageously increases the available suction provided by the endoscope, thereby achieving greater tissue retraction.
[0092] Further considering the endoscopic tissue resection device 100, as described above, based on the orientation and stability provided by the spring wire 108 and two opposing wire portions 164 of a foldable snare wire 142 positioned juxtaposed with the distal opening 118 of the cap 102, the foldable snare wire 142 is closely aligned with the inner circumference of the distal opening 118 of the cap 102 and flush with the distal edge 180 of the distal end 116 of the cap 102. Figure 8 , 11 Moreover, as noted, the foldable snare wire 142 is closely aligned with and flush with the inner circumference of the distal opening 118 of the cap 102, which ensures that the tissue is surrounded and captured by the foldable snare wire 142 when the tissue is drawn back into the cap 102 by suction.
[0093] Therefore, in some embodiments, the inner circumference 184 of the distal opening 118 of the cap 102 has a diameter 186, and the foldable snare wire 142 in the expanded state 144 is sufficiently closely juxtaposed with the inner circumference 184 of the distal opening 118 of the cap 102 such that any gap 188 between the two opposing wire portions 164 of the foldable snare wire 142 and the inner circumference 184 of the distal opening 118 of the cap 102 does not exceed 10%, 8%, 6%, 4%, or 2% of the diameter 186 of the inner circumference 184 of the distal opening 118 of the cap 102. Figure 2 , 3 8).
[0094] In some embodiments, the distal opening 118 of the cap 102 has an inner circumference 184, and the foldable snare wire 142 in the expanded state 144 is sufficiently closely juxtaposed with the inner circumference 184 of the distal opening 118 of the cap 102 such that the gap 190 between the two opposing wire portions 164 of the foldable snare wire 142 and the inner circumference 184 of the distal opening 118 of the cap 102 does not exceed 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm. Figure 2 , 3 8).
[0095] In some embodiments, the distal end 116 of the cap 102 has a distal edge 180, the cavity 120 of the cap 102 has an internal depth 132, and the foldable snare wire 142 in the expanded state 144 rests fully flush with the distal edge 180 of the distal end 116 of the cap 102, such that any gap 190 between the two opposing wire portions 164 of the foldable snare wire 142 and the distal edge 180 of the distal end 118 of the cap 102 is not greater than 20%, 16%, 12%, 8%, or 4% of the internal depth 132 of the cavity 120 of the cap 102. Figure 2 , 3 8).
[0096] In some embodiments, the distal end 116 of the cap 102 has a distal edge 180, the cap 102 has an axis 194 extending from the proximal end 112 of the cap 102 to the distal end 116 of the cap 102, and the foldable snare wire 142 in the expanded state 144 is fully flush with the distal edge 180 of the distal end 116 of the cap 102, such that any gap 190 between the two opposing wire portions 164 of the foldable snare wire 142 and the distal edge 180 of the distal end 116 of the cap 102 is measured along the axis 194 to be no more than 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm. Figure 2 , 3 8).
[0097] The foldable snare wire 142 can be further shaped such that it exits the snare sheath 104 at an angle relative to the longitudinal orientation of the endoscope. Figure 6 , 11 This helps allow the size and shape of the foldable snare wire 142, in its expanded state 144, to fit closely to the inner circumference of the distal opening 118 of the hood 102 and rest substantially flush with the distal edge 180 of the distal end 116 of the hood 102. Thus, in some embodiments, the snare sheath 104 has an axis 196 extending from its proximal end 146 to its distal end 126, and the foldable snare wire 142 is shaped to deflect from the axis 196 during extension of the foldable snare wire 142 from the distal end 126 of the snare sheath 104.
[0098] Near the distal end 126 of the snare sheath 104, where it is fixed along the inner periphery 122 of the cap body 110, a blade 198 may be provided so that the tissue captured by the foldable snare wire 142 can be better cut as the foldable snare wire 142 is folded. Figure 18Therefore, in some embodiments, the endoscopic tissue resection device 100 also includes a blade 198 disposed in the cavity 120 of the cap 102 adjacent to the distal end 126 of the snare sheath 104. According to these embodiments, the blade 198 may be oriented to shear tissue captured by the foldable snare wire 142 when the foldable snare wire 142 is folded; for example, the blade 198 may be oriented distally.
[0099] The snare actuator handle 182 used with the endoscopic tissue resection device 100 may include an accessory for standard surgical energy. In some embodiments, the diameter of the foldable snare wire 142 may also be varied, allowing for “cold” (no energy) or “hot” (electrical) application to cut tissue and / or use of the snare 106 to grip tissue. In the case of the “hot” snare 106, the spring wire 108 should be insulated, for example, with a plastic collar to reduce the energy transmitted to the tissue through the spring wire 108.
[0100] In some embodiments, the endoscopic tissue resection device 100 may include additional spring wires 108, such as up to two, three, four, or five spring wires 108 in total, to position two opposing wire portions 164 of the foldable snare wire 142 juxtaposed with the distal opening 118 of the cap 102, for example, to restore the approximate hexagonal, circular, or elliptical shape of the two opposing wire portions 164 of the foldable snare wire 142 such that the foldable snare wire 142 is closely aligned with the inner circumference of the distal opening 118 of the cap 102 and flush with the distal edge 180 of the distal end 116 of the cap 102. According to these embodiments, the proximal ends 168 of the additional spring wires 108 are attached to or near the proximal end 112 of the cap 102, and the distal ends 170 are attached to the foldable snare wire 142 at fixed points ranging from 90° to 270° relative to the base 160 of the foldable snare wire 142 corresponding to 0° and the apex 162 of the foldable snare wire 142 corresponding to 180°. Attaching the additional spring wires 108 to the fixed points in this manner provides improved alignment and positioning of the two opposing wire portions 164 of the foldable snare wire 142 relative to the inner circumference of the distal opening 118 of the cap 102 and the distal edge 180 of the distal end 116 of the cap 102, without interfering with the expansion of the foldable snare wire 142.
[0101] Furthermore, in some embodiments, the endoscopic tissue resection device 100 may include, in addition to one or more spring wires 108, a mechanism for achieving this, such as an elastic membrane.
[0102] In some embodiments, the apex of the foldable snare wire can be fixed, and the foldable snare wire or sheath can be a spring component such that the sheath moves toward the apex when the snare wire retracts.
[0103] In some embodiments, the apex of the foldable snare wire and the snare sheath may each include spring components such that each spring component moves toward each other to close in or near the center of the cap.
[0104] In some embodiments, the endoscopic tissue resection device 100 can be used for tissue evaluation.
[0105] While the invention has been described in conjunction with the specific embodiments outlined above, it will be apparent to those skilled in the art that many alternatives, modifications, and variations will be readily apparent. Therefore, the preferred embodiments of the invention described above are intended to be illustrative and not restrictive. Various changes may be made without departing from the spirit and scope of the invention.
Claims
1. An endoscopic tissue resection device configured to be attached to the distal end of an endoscope, the endoscopic tissue resection device comprising a cap, a snare sheath, a snare, and a spring wire, wherein: The hood includes a hood body, a proximal end, a proximal opening, a distal end, and a distal opening; The cap body defines a cavity for tissue retraction and has an inner periphery; The snare sheath includes a proximal end, a distal end, and a snare sheath located between them; The distal end of the snare sheath is connected to the hood body along the inner periphery of the hood body; The snare includes a snare actuation cable and a foldable snare wire; The snare actuation cable includes a proximal end, a distal end, and a snare actuation cable body located therebetween, disposed within the snare sheath, and configured to translate proximally and distally within the snare sheath. The foldable snare wire includes a base, a vertex opposite to the base, and two opposing wire portions extending therebetween, disposed within the cavity of the cap, and capable of reversibly folding from an expanded state to a folded state. The base of the foldable snare wire is attached to the snare actuation cable at or near the distal end of the snare actuation cable. The foldable snare wire is configured to retract from the cavity of the cap into the snare sheath by translating the snare actuation cable proximally within the snare sheath, the foldable snare wire reversibly folding from the expanded state to the folded state upon retraction, and to be pushed out from the snare sheath into the cavity of the cap by translating the snare actuation cable distally within the snare sheath, the foldable snare wire reversibly expanding to the expanded state upon extension; The spring wire is disposed within the cavity of the cap and includes a proximal end, a distal end, and a flexible portion located therebetween; The proximal end of the spring wire is attached to the body of the cap at or near the proximal end of the cap; The distal end of the spring wire is attached to the apex of the foldable snare wire. The spring wire is reversibly deflected from a stationary state to a deflected state. When the foldable snare wire is placed in the cavity of the cap, the spring wire is in a stationary state, and when the foldable snare wire is retracted into the snare sheath, the spring wire deflects to the deflected state. In the stationary state, the spring wire orients and stabilizes the apex of the foldable snare wire within the cap, located at or near the distal opening of the cap, opposite the distal end of the snare sheath, such that the two opposing wire portions of the foldable snare wire are positioned juxtaposed with the distal opening of the cap. During deflection, the spring wire bends along an arc-shaped path to the snare sheath; and The distal end of the snare sheath is recessed into the cavity of the cap relative to the distal end of the spring wire, allowing the spring wire to bend along an arcuate path.
2. The endoscopic tissue resection device according to claim 1, wherein, The cap has an outer diameter of 0.5 to 1.5 cm.
3. The endoscopic tissue resection device according to claim 1, wherein, The cavity of the cap has an internal depth of 0.5 cm to 1.5 cm.
4. The endoscopic tissue resection device according to claim 1, wherein, The cavity of the cap has an inner diameter, the spring wire has a length, and the inner diameter of the cavity of the cap is greater than the length of the spring wire.
5. The endoscopic tissue resection device according to claim 1, wherein, The distal end of the hood has a sloping profile.
6. The endoscopic tissue resection device according to claim 1, wherein, The distal end of the cap includes a lip located within the cavity of the cap for retaining the foldable snare wire within the cavity of the cap.
7. The endoscopic tissue resection device according to claim 1, wherein, The two opposing wire portions of the foldable snare wire have an approximately hexagonal, circular, or elliptical shape in the expanded state.
8. The endoscopic tissue resection device according to claim 1, wherein, The distal opening of the cap has an inner circumference having a diameter, and the foldable snare wire in the expanded state is sufficiently closely juxtaposed with the inner circumference of the distal opening of the cap such that any gap between the two opposing wire portions of the foldable snare wire and the inner circumference of the distal opening of the cap does not exceed 10%, 8%, 6%, 4%, or 2% of the diameter of the inner circumference of the distal opening of the cap.
9. The endoscopic tissue resection device according to claim 1, wherein, The distal opening of the cap has an inner circumference, and the foldable snare wire in the expanded state is sufficiently closely juxtaposed with the inner circumference of the distal opening of the cap such that any gap between the two opposing wire portions of the foldable snare wire and the inner circumference of the distal opening of the cap does not exceed 5 mm, 4 mm, 3 mm, 2 mm or 1 mm.
10. The endoscopic tissue resection device according to claim 1, wherein, The cap has a distal edge at its distal end, the cavity of the cap has an internal depth, and the foldable snare wire in the expanded state is fully flush with the distal edge of the cap's distal end, such that any gap between the two opposing wire portions of the foldable snare wire and the distal edge of the cap's distal end does not exceed 20%, 16%, 12%, 8%, or 4% of the internal depth of the cap's cavity.
11. The endoscopic tissue resection device according to claim 1, wherein, The cap has a distal edge at its distal end, the cap has an axis extending from the proximal end of the cap to the distal end of the cap, and the foldable snare wire in the expanded state is fully flush with the distal edge of the distal end of the cap, such that any gap between the two opposing wire portions of the foldable snare wire and the distal edge of the distal end of the cap, measured along the axis, does not exceed 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm.
12. The endoscopic tissue resection device according to claim 1, wherein, The snare sheath has an axis extending from its proximal end to its distal end, and the foldable snare wire is shaped such that it deflects from the axis during the extension of the foldable snare wire from the distal end of the snare sheath.
13. The endoscopic tissue resection device according to claim 1, wherein, The endoscopic tissue resection device also includes a blade disposed in the cavity of the cap adjacent to the distal end of the snare sheath.