Patent Description:
Endoscopic resection procedures, such as diagnostic tissue acquisition from the digestive tract, may be performed with an endoscope and an endoscopic resection device. In general, an endoscope includes a long flexible insertion tube having one or more channels through which miniaturized, flexible instruments can be inserted and advanced. The endoscope typically includes various optical features allowing for visualization of internal views of particular body parts, organs, or passages without requiring invasive surgery. For example, the insertion tube may transmit images or image-producing signals from the illuminated operative site to a viewing means, providing the operator with full vision of the actions being performed at the working end of the endoscope.

In some endoscopic full thickness resection procedures, the operator first identifies a tissue such as a lesion in the digestive tract. The tissue is pulled into a cap provided on the endoscopic device via suction or other means. Next, a clip is deployed over the tissue. Lastly, a cutting device such as a snare cuts over the top of the clip, removing the tissue and leaving the clip closed over the otherwise open defect.

The clip should be deployed before the cutting in order to pre-close the defect resulting from the cutting. Also, the clip should remain at the resection site until the body can heal itself.

<CIT> relates generally to the field of tissue ligation, and more particularly to an improved device and method for electrosurgically severing lesions. <CIT> relates to a method, a system and subsystems thereof for endoscopic full thickness resection surgical procedures, typically, but not necessarily, of the gastrointestinal (GI) tract. <CIT> relates generally to systems and methods for resecting tissue, and more particularly, to systems for endoscopic mucosal resection. <CIT> relates to a system for attaching devices to the distal end of endoscopic instruments. <CIT> relates generally to devices and methods for securing inverted tissue, and more particularly, though not exclusively, to securing inverted diverticulum serosa to serosa.

Therefore, there is a need for preventing the cutting of the tissue before the clip is deployed. There is also a need for ensuring that some tissue remain on top of the clip after resection and removal of the tissue, such that the clip can remain locked onto the resection site.

The present invention provides endoscopic resection assemblies for use in endoscopic procedures. No surgical methods are claimed.

The present invention provides an endoscopic resection assembly (<NUM>), comprising: (a) an adaptor (<NUM>), configured to couple to an endoscopic device; (b) a pusher (<NUM>), disposed on the adaptor (<NUM>); (c) at least one driver, configured to move the pusher (<NUM>) in a distal direction with respect to the adaptor (<NUM>); and (d) a cutting device (<NUM>), removably coupled to the pusher (<NUM>), wherein the cutting device (<NUM>) is configured to be removed from the pusher (<NUM>) when at least a portion of the pusher is distal to the adaptor (<NUM>), wherein the adaptor (<NUM>) is configured to be loaded with a clip (<NUM>), wherein the clip (<NUM>) is configured to operate between an open state and a closed state. wherein the clip (<NUM>) is configured to be loaded on the adaptor (<NUM>) in the open state at a position distal to the pusher (<NUM>), wherein the clip (<NUM>) is configured to be pushed by the pusher (<NUM>) to slide off the distal edge (<NUM>) of the adaptor (<NUM>) so that the clip (<NUM>) is configured to be released from the adaptor (<NUM>) and to engage onto a tissue before the cutting device (<NUM>) is removed from the pusher (<NUM>).

Further features and advantages of the invention will become apparent from the following detailed description made with reference to the accompanying drawings.

The invention now will be described more fully hereinafter. As used in the specification, and in the appended claims, the singular forms "a", "an", and "the", include plural referents unless the context clearly dictates otherwise.

The present invention can be used for cutting into or through the muscularis of the GI tract in order to remove dysplasia that has invaded past the mucosal layer of tissue. A clip can be deployed over the tissue prior to resection in order to pre-close the resulting defect created from the resection.

As illustrated in <FIG> and <FIG>, as per the invention, an endoscopic resection assembly <NUM> includes an adaptor <NUM>, a pusher <NUM>, a cutting device <NUM>, and a clip <NUM>. The adaptor <NUM> is configured to attach to an endoscopic device. As illustrated in <FIG>, the pusher <NUM> is disposed on the adaptor <NUM> and configured to slide in the axial direction with respect to the adaptor <NUM>. The cutting device <NUM> is an endoscopic tool for cutting a tissue, which operates between an open state and a closed state. As illustrated in <FIG> and <FIG>, the cutting device <NUM> is removably coupled to the pusher <NUM>. The clip <NUM> is an endoscopic tool configured to operate between an open state and a closed state, and is configured to engage onto a tissue. As illustrated in <FIG>, the clip <NUM> is loaded on the adaptor <NUM> in the open state at a position distal to the pusher <NUM>. The endoscopic resection assembly <NUM> further includes at least one driver, controlled by an operator, configured to slide the pusher <NUM> in the distal direction with respect to the adaptor <NUM>. As the pusher <NUM> slides in the distal direction with respect to the adaptor <NUM>, the clip <NUM> is pushed by the pusher <NUM> to slide off the distal edge <NUM> of the adaptor <NUM>, and engages onto a tissue by reforming toward the closed state. The cutting device <NUM> can then be activated by the operator to detach from the pusher <NUM>, and resect tissue above the pusher by operating toward the closed state.

As illustrated in <FIG> and <FIG>, the endoscopic resection assembly <NUM> may include at least one driver and at least one sheath, a catheter <NUM>, a clip deployment handle <NUM>, and a handle <NUM>. The at least one driver may comprise a first driver <NUM> and a second driver <NUM>. The at least one sheath may comprise a first sheath <NUM> and a second sheath <NUM>. The drivers may be directly adjacent to one another or spaced apart somewhat along the circumference of the pusher <NUM>. For example, the drivers may be spaced about <NUM> degrees to <NUM> degrees, or about <NUM> degrees to <NUM> degrees, or about <NUM> degrees, apart from one another.

<FIG> illustrates the assembly of the distal components of the endoscopic resection assembly <NUM>, including the pusher <NUM>, the cutting device <NUM>, and the at least one driver. The cutting device <NUM> is an endoscopic tool for cutting a tissue, and operates between an open state and a closed state. The cutting device <NUM> has a snare drive cable <NUM> and a snare loop <NUM>. The pusher <NUM> includes at least one retainer. As illustrated in <FIG>, the at least one retainer comprises the first retainer <NUM> and the second retainer <NUM>, and retains the snare loop <NUM>, such that the cutting device <NUM> is removably coupled to the pusher <NUM>. The pusher <NUM> is driven by the at least one driver. As illustrated in <FIG>, the at least one driver comprises the first driver <NUM> and the second driver <NUM>. The first driver <NUM> and the second driver <NUM> can be actuated to move the pusher <NUM> in the distal direction.

As illustrated in <FIG>, the pusher <NUM> is disposed on the adaptor <NUM> and configured to slide in the axial direction with respect to the adaptor <NUM>. The adaptor <NUM> may comprise a material to reduce friction and support movement of the pusher <NUM> and the clip <NUM>. Suitable materials for the adaptor <NUM> include plastics such as polycarbonate, K-resin, acrylic, xylar, ASA, polypropylene, silicone, and TPES, or other similar materials. The adaptor <NUM> may comprise such plastics, or other materials, entirely or in part. The clip <NUM> is an endoscopic tool configured to operate between an open state and a closed state, and is configured to engage onto a tissue. The clip <NUM> is loaded on the adaptor in the open state at a position distal to the pusher <NUM>. The pusher <NUM> and the clip <NUM> may not be secured together. However, the pusher <NUM> and the clip <NUM> may be secured together. For example, one or more indents can be formed on the pusher <NUM>, and one or more protrusions can be formed on the clip <NUM>, where the one or more protrusions are configured to be secured into the one or more indents. The pusher <NUM> and the clip <NUM> can be secured together by other means such as welding, gluing, and overmolding. The snare drive cable <NUM> of the cutting device <NUM> extends within the catheter <NUM>. The catheter <NUM> may be coupled with the adaptor <NUM>. The at least one driver may respectively extend within the at least one sheath. As illustrated in <FIG>, the first driver <NUM> and the second driver <NUM> respectively extend within the first sheath <NUM> and the second sheath <NUM>. The at least one sheath can be attached to the adaptor <NUM>.

The at least one driver can be actuated to move the pusher <NUM> in the distal direction. As a result, the pusher <NUM> slides in the distal direction with respect to the adaptor <NUM>. As the pusher <NUM> slides in the distal direction with respect to the adaptor <NUM>, the clip <NUM> is pushed by the pusher to slide off the distal edge <NUM> of the adaptor <NUM>, and engage onto a tissue by reverting to the closed state. The cutting device <NUM> can be activated to detach from the pusher <NUM>, and cut a tissue by operating toward the closed state.

As illustrated in <FIG>, the adaptor <NUM> has an inside surface and an outside surface. The adaptor <NUM> may include a lumen <NUM> and at least one overmolding. As illustrated in <FIG>, the at least one overmolding may comprise an overmolding <NUM> and an overmolding <NUM>.

The adaptor <NUM> may be substantially tubular with a distal open end and a proximal open end. The adaptor <NUM> may be hollow and define a tissue chamber channel. The adaptor <NUM> may be configured to attach with different types of endoscopic devices (e.g., Olympus®, Fujinon®, or Pentax® endoscopes). For example, the inner and outer surface of the adaptor <NUM> may be contoured, and the inner and outer diameter of the adaptor <NUM> may be varied, in order to provide a good fit with the endoscopic device. The endoscopic device may be press-fitted to the proximal end of the adaptor <NUM>. Flexible materials, such as rubber and other elastic polymers, can be overmolded or glued on the inside surface of the adaptor <NUM> in order to strengthen the fitting of the endoscopic device and the adaptor <NUM>. The adaptor <NUM> may comprise a flexible band, such as a rubber band, configured to be wrapped around the distal end of the endoscopic device. A person skilled in the art should understand that the shape of the adaptor <NUM> or the shape the tissue chamber channel can be any suitable shapes as long as it does not interfere with the operations of the endoscopic device. The tissue chamber channel may be configured to receive the tissue to be resected during resection operation. The adaptor <NUM> may be entirely or partially formed with materials sufficiently transparent to allow visualization of outside environment through various optical features from the inside of the adaptor <NUM>. During resection operation, the sufficiently transparent materials may allow the operator to confirm whether the clip <NUM> is deployed, and observe the position of the cutting device <NUM> prior to tissue resection.

The adaptor <NUM> is configured to allow the clip <NUM> and the pusher <NUM> to be disposed on the adaptor <NUM>. As illustrated in <FIG>, the adaptor <NUM> is configured to allow the clip <NUM> and the pusher <NUM> to be disposed on the outside surface of the adaptor <NUM>. The adaptor <NUM> is configured to allow the clip <NUM> and the pusher <NUM> to slide in the axial direction with respect to the adaptor <NUM>. As illustrated in <FIG>, the outside surface of the adaptor <NUM> may be a smooth surface such that the clip <NUM> and the pusher <NUM> can slide in the axial direction with respect to the adaptor <NUM>.

A person skilled in the art should understand that the adaptor <NUM> may have any shape and may include any structural components, as long as the clip <NUM> and the pusher <NUM> can be disposed on the adaptor <NUM> and slide in the axial direction with respect to the adaptor <NUM>. For example, the adaptor <NUM> is configured to allow the clip <NUM> and/or the pusher <NUM> to be disposed on the inside surface of the adaptor <NUM>. The adaptor <NUM> may include a support surface formed inside the adaptor <NUM>, such that the clip <NUM> and/or the pusher <NUM> can be disposed on the support surface. The adaptor <NUM> can include one or more guide rails, such that the clip <NUM> and/or the pusher <NUM> are allowed to slide in the axial direction along the one or more guide rails. The adaptor <NUM> can include one or more longitudinal slits, such that the clip <NUM> and/or the pusher <NUM> are allowed to slide in the axial direction along the one or more longitudinal slits.

The adaptor <NUM> may be configured to couple with the catheter <NUM>. As illustrated in <FIG>, , the adaptor <NUM> is coupled with the catheter <NUM> by inserting the catheter <NUM> into the lumen <NUM> of the adaptor <NUM>. The lumen <NUM> may be formed on the outside surface of the adaptor <NUM>, such that the catheter <NUM> is coupled with the outside surface of the adaptor <NUM>. The lumen <NUM> may provide slip fit between the catheter <NUM> and the adaptor <NUM>, such that the catheter <NUM> is allowed to freely slide in the axial direction with respect to the adaptor <NUM>. A person skilled in the art should understand that the catheter <NUM> may be coupled to any portion of the adaptor <NUM>, such as the inside surface of the adaptor <NUM>, as long as the catheter <NUM> does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>. The catheter <NUM> may penetrate the adaptor <NUM>, such that the catheter <NUM> extends through a hole formed on the adaptor <NUM>. In addition, a person skilled in the art should understand that the adaptor <NUM> can be fixed with the catheter <NUM>, or be detached from the catheter <NUM>, as long as the catheter <NUM> does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>.

The adaptor <NUM> may be configured to attach with the at least one sheath. As illustrated in <FIG>, the at least one sheath may comprise the first sheath <NUM> and the second sheath <NUM>, and the first sheath <NUM> and the second sheath <NUM> may be attached to the adaptor <NUM> respectively by the overmolding <NUM> and the overmolding <NUM>. The overmolding <NUM> and the overmolding <NUM> may be formed on the outside surface of the adaptor <NUM>, such that the at least one sheath is attached to the outside surface of the adaptor <NUM>. A person skilled in the art should understand that the at least one sheath can be attached with the adaptor <NUM> by other means, for example, friction, heat staking, gluing, or welding. A person skilled in the art should also understand that the at least one sheath can be attached to any portion of the adaptor <NUM>, such as the inside surface of the adaptor <NUM>, as long as the at least one sheath does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>. The at least one sheath may penetrate the adaptor <NUM>, such that the at least one sheath extends through a hole formed on the adaptor <NUM>. In addition, a person skilled in the art should understand that the at least one sheath may not be attached with the adaptor <NUM>. Instead, the at least one sheath may be attached with any component of the endoscopic device or the endoscopic resection assembly <NUM>, as long as the at least one sheath does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>.

As illustrated in <FIG>, the pusher <NUM> includes at least one knob which comprises the first knob <NUM> and the second knob <NUM>, and at least one retainer which comprises the first retainer <NUM> and the second retainer <NUM>.

The pusher <NUM> may be configured to be disposed on the adaptor <NUM> and can slide in the axial direction with respect to the adaptor <NUM>. As illustrated in <FIG>, the pusher <NUM> is substantially ring-shaped, defining a central opening <NUM>. As illustrated in <FIG>, the adaptor can be inserted into the central opening <NUM>, such that the pusher <NUM> is disposed on the outside surface of the adaptor <NUM> and can slide in the axial direction with respect to the adaptor <NUM>. The central opening <NUM> may have different shapes to fit with the different shapes of the outside surface of the adaptor <NUM>. The pusher <NUM> may be configured to be disposed on the inside surface or the outside surface of the adaptor <NUM>, or on a support surface formed inside the adaptor <NUM>. The pusher <NUM> may include structural components, such as protrusions and indents, to fit with guide rails, longitudinal slits, or other structural components of the adaptor <NUM>, such that the pusher <NUM> can slide in the axial direction with respect to the adaptor <NUM>.

The pusher <NUM> may have a closed ring structure configured to be disposed on the entire periphery of the adaptor <NUM>, as illustrated in <FIG>. A person skilled in the art should understand that the pusher <NUM> may be disposed on a portion of the periphery of the adaptor <NUM>, as long as there is no interference with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>. For example, the pusher <NUM> may have a half-ring structure configured to be disposed on a half of the periphery of the adaptor <NUM>.

The pusher <NUM> may be attached with at least one driver. The pusher <NUM> may include at least one knob for attaching with the at least one driver. As illustrated in <FIG>, the at least one driver comprises a first driver <NUM> and a second driver <NUM>, and the at least one knob comprises the first knob <NUM> and the second knob <NUM>. As illustrated in <FIG> and <FIG>, the distal ends of the first driver <NUM> and the second driver <NUM> are bent into a circle and fitted around the first knob <NUM> and the second knob <NUM>. As such, the at least one driver is secured to the at least one knob of the pusher <NUM>. The at least one knob is a round knob over which the bent distal end of the at least one driver can be snapped into place. A person skilled in the art should understand that the at least one driver may fit with, or be secured to, other structural components of the pusher <NUM>, for example, one or more holes formed on the pusher <NUM>. Glue may be applied to reinforce the attachment of the at least one driver to the pusher <NUM>. The at least one driver may be attached to the pusher <NUM> by different means, for example, gluing, welding, or overmolding.

The at least one driver is configured to move the pusher <NUM> in the distal direction. As illustrated in <FIG>, the first driver <NUM> and the second driver <NUM> respectively extend within the first sheath <NUM> and the second sheath <NUM>. The first driver <NUM> and the second driver <NUM> can be actuated to advance in the distal direction with respect to the first sheath <NUM> and the second sheath <NUM>, pushing the pusher <NUM> in the distal direction. A person skilled in the art should understand that the at least one driver may comprise various structural components configured to move the pusher <NUM> in the distal direction. For example, the at least one driver can comprise a pull thread with a distal end tied on the pusher <NUM>, where the pull thread is configured to pull the pusher <NUM> in the distal direction when a proximal end of the pull thread is retracted. A person skilled in the art should also understand that the at least one driver may not be coupled or attached to the pusher <NUM>, as long as the pusher <NUM> can be driven by the at least one driver in the distal direction.

A spring may be coupled to the clip deployment handle <NUM> or the at least one sheath. The spring can be configured to be compressed or extended, such that the spring exerts a force on the at least one driver in the axial direction. The clip deployment handle <NUM> can include a stopper for preventing the axial movement of the at least one driver with respect to the at least one sheath. The clip deployment handle <NUM> can be configured to activate the stopper by, for example, deforming the stopper, such that the stopper no longer prevents the axial movement of the at least one driver. As result, the compressed or extended spring moves the at least one driver in the axial direction with respect to the at least one sheath, and the at least one driver moves the pusher <NUM> in the distal direction.

The pusher <NUM> may be spring loaded on the adaptor <NUM>. A spring can be coupled with the adaptor <NUM> and configured to be compressed or extended by the pusher <NUM> when the pusher <NUM> is disposed on the adaptor <NUM>. As such, the spring exerts a force on the pusher <NUM> in the distal direction. A stopper can be coupled to the adaptor <NUM>, the endoscopic device, or other structural components of the endoscopic resection assembly <NUM>, and can be configured to prevent the distal movement of the pusher <NUM> with respect to the adaptor <NUM>. An actuator, such as a pull thread extending within a sheath, can be operatively coupled with the stopper. The actuator may be configured to activate the stopper by, for example, deforming the stopper or detaching the stopper from other structural components, such that the stopper no longer prevents the distal movement of the pusher <NUM>. As result, the compressed spring pushes the pusher <NUM>, and the pusher <NUM> slides in the distal direction with respect to the adaptor <NUM>.

The adaptor <NUM> may be slidably coupled with the endoscopic device, such that the adaptor <NUM> can slide in the axial direction with respect to the endoscopic device. An actuator, such as a pull thread extending within a sheath, can be operatively coupled with the adaptor. The actuator may be configured to move the adaptor <NUM> in the proximal direction with respect to the endoscopic device and the pusher <NUM>, such that the pusher <NUM> moves in the distal direction in relative to the adaptor <NUM>.

The pusher <NUM> may be removably coupled with the cutting device <NUM>. The cutting device <NUM> is an endoscopic tool for cutting a tissue, which operates between an open state and a closed state. As illustrated in <FIG>, the cutting device <NUM> includes a snare drive cable <NUM> and a snare loop <NUM>. <FIG> illustrates the cutting device <NUM> in the open state. The snare drive cable <NUM> can be actuated to contract the snare loop <NUM>, such that the cutting device <NUM> operates toward the closed state.

The pusher <NUM> includes at least one retainer. As illustrated in <FIG>, the at least one retainer may comprise a first retainer <NUM> and a second retainer <NUM>. Each of the at least one retainer may define a passage and a slit. As illustrated in <FIG>, the first retainer <NUM> defines a passage <NUM> and a slit <NUM>, and the second retainer <NUM> defines a passage <NUM> and a slit <NUM>. The passage defined by the at least one retainer may be configured to accommodate the snare loop <NUM> of the cutting device <NUM>. The slit defined by the at least one retainer may be configured to communicate the passage with the central opening <NUM> defined by the pusher <NUM>. <FIG> illustrates the assembly of the cutting device <NUM> with the pusher <NUM>. As illustrated in <FIG>, the snare loop <NUM> is in the open state and accommodated in the passage <NUM> defined by the first retainer <NUM> and the passage <NUM> defined by the second retainer <NUM>. As such, the snare loop <NUM> lies in a plane substantially parallel to the plane defined by the pusher <NUM>, and moves in tandem with the pusher <NUM> when the pusher <NUM> moves in the axial direction. When the snare loop <NUM> is contracted by actuating the snare drive cable <NUM>, the slit <NUM> defined by the first retainer <NUM> and the slit <NUM> defined by the second retainer <NUM> allow the snare loop <NUM> to escape from the passage and move radially inward into the central opening <NUM> defined by the pusher <NUM>. The pusher <NUM> can be formed from one or more components that could be snapped, glued, or welded together to form the at least one retainer that removably retains the cutting device <NUM> to the pusher <NUM>.

The pusher <NUM> may include at least one housing formed around the at least one knob. As illustrated in <FIG>, a housing <NUM> can be formed around the knob <NUM> and a housing <NUM> can be formed around the knob <NUM>. As illustrated in <FIG>, the snare loop <NUM> is bent at the positions where the at least one housing is located, such that the snare loop <NUM> is positioned along the inward facing surface of the at least one housing. As such, the at least one housing does not block the operation of the snare loop <NUM> between the open state and the closed state. A person skilled in the art should understand that the snare loop <NUM> can be bent or deformed to extend around various structural components formed on the pusher <NUM>, such that the structural components do not block the operation of the snare loop <NUM> between the open state and the closed state. A person skilled in the art should also understand that passages for accommodating the snare loop <NUM> can be formed on the surface of the various structural components of the pusher <NUM>, such that the structural components do not block the operation of the snare loop <NUM> between the open state and the closed state.

As illustrated in <FIG>, the at least one retainer is formed on the proximal surface of the pusher <NUM>. As such, when the snare loop <NUM> is accommodated in the passage formed through the at least one retainer, the snare loop <NUM> is positioned at a set distance from the distal surface of the pusher <NUM>. The set distance can be, for example, <NUM> to <NUM> or <NUM> to <NUM>. The set distance can be varied depending on user need and anatomical constraints. A person skilled in the art should understand that the at least one retainer may comprise various structural components configured to removably couple with the cutting device <NUM>. IThe at least one retainer may comprise a groove configured to hold the snare loop <NUM>. The at least one retainer may comprise holes or indents configured to fit with bent or protruding portions of the snare loop <NUM>. A person skilled in the art should also understand that the at least one retainer may be formed on any portion of the pusher <NUM>, for example, the proximal surface, the distal surface, the inward facing surface, or the outward facing surface.

The pusher <NUM> can be removably coupled with the snare loop <NUM> by various means. The snare loop <NUM> can be detachably glued to the pusher <NUM>. The snare loop <NUM> can be magnetically attached to the pusher <NUM>. The snare loop <NUM> can be removably coupled to the pusher <NUM> by a breakable seal. The breakable seal may comprise a rigid seal attached to the pusher <NUM> and configured to detach from the pusher <NUM>. The breakable seal may also comprise a soft seal attached to the pusher <NUM>, where the snare loop <NUM> is configured to break the seal by cutting through the soft seal. A person skilled in the art should understand that when the snare loop <NUM> is removably coupled with the pusher <NUM>, the snare loop <NUM> can be positioned at a set distance from the distal surface of the pusher <NUM>, where the set distance can be, for example, <NUM> to <NUM> or <NUM> to <NUM>.

The cutting device <NUM> is an endoscopic tool for resecting tissue, and operates between an open state and a closed state. As illustrated in <FIG>, the cutting device <NUM> includes the snare drive cable <NUM> and the snare loop <NUM>. The snare drive cable <NUM> and the snare loop <NUM> may be formed with conductive metal wire, which allows the use of diathermic energy by directing electric current in the snare drive cable <NUM> and the snare loop <NUM>. The snare drive cable <NUM> and the snare loop <NUM> can be formed with materials including stainless steel, nitinol, nickel-titanium shape memory alloy, and polymers such as PTFE, polyolefin, and fluorinated ethylene propylene. The snare drive cable <NUM> can be attached to the snare loop <NUM> by welding at an angle substantially perpendicular to the plane defined by the snare loop <NUM>. As illustrated in <FIG>, the snare drive cable <NUM> extends within the catheter <NUM>. The proximal end of the snare drive cable <NUM> is operatively coupled with the handle <NUM>. <FIG> and <FIG> illustrate the cutting device <NUM> in the open state. The handle <NUM> may be configured to retract the snare drive cable <NUM> with respect to the catheter <NUM>. As result, the snare drive cable <NUM> pulls a portion or the entirety of the snare loop <NUM> into the catheter <NUM>, such that the snare loop <NUM> is contracted toward the closed state having a smaller loop area than the loop area of the open state.

The cutting device <NUM> may be one integral piece of wire. The cutting device <NUM> may extend within the catheter <NUM> from the proximal end to the distal end, protrudes out of the distal end of the catheter <NUM> to form a snare loop, and extends within the catheter <NUM> back from the distal end to the proximal end. As such, both ends of the cutting device <NUM> are positioned at the proximal end of the catheter <NUM>, where the catheter <NUM> is operatively coupled with the handle <NUM>. The handle <NUM> may be configured to actuate the cutting device <NUM> by retracting one end or both ends of the cutting device <NUM> with respect to the catheter <NUM>, such that the snare loop <NUM> is contracted.

The cutting device <NUM> may be one integral piece of wire. The cutting device <NUM> may extend within the catheter <NUM>, with the proximal end positioned at the proximal end of the catheter <NUM> and the distal end attached to the distal end of the catheter <NUM>. The handle <NUM> may be configured to actuate the cutting device <NUM> by retracting the proximal end of the cutting device <NUM> with respect to the catheter <NUM>, such that the snare loop <NUM> is contracted.

The cutting device <NUM> may be removably coupled with the pusher 180As illustrated in <FIG>, the snare loop <NUM> of the cutting device <NUM> may be retained in the passage <NUM> and the passage <NUM> defined by the at least one retainer of the pusher <NUM>. When the snare drive cable <NUM> is retracted by the handle <NUM>, the snare loop <NUM> is contracted to escape from the passage <NUM> and the passage <NUM> through the slit <NUM> and the slit <NUM> defined by the pusher <NUM>, and move radially inward into the central opening <NUM> defined by the pusher <NUM>.

A person skilled in the art should understand that the cutting device <NUM> may comprise any known endoscopic tools for cutting a tissue, as long as the cutting device <NUM> can be removably coupled with the pusher <NUM>. The cutting device <NUM> may comprise one or more jaws for cutting a tissue. A person skilled in the art should also understand that the cutting device <NUM> may be removably coupled to any portion of the pusher <NUM>, for example, the proximal surface, the distal surface, the inward facing surface, or the outward facing surface of the pusher <NUM>. In addition, a person skilled in the art should understand that the cutting device <NUM> can be positioned at a set distance from the distal surface of the pusher <NUM>, where the set distance can be, for example, <NUM> to <NUM> or <NUM> to <NUM>.

As illustrated in <FIG>, the cutting device <NUM> may be removably coupled to the pusher <NUM> in the open state. A person skilled in the art should understand that the cutting device <NUM> may comprise various endoscopic tools allowing the operation between an open state and a closed state. The cutting device <NUM> may be removably coupled to the pusher <NUM> in the closed state or an intermediate state between the open state and the closed state.

The clip <NUM> may be an endoscopic clip which can be deployed to engage onto a tissue. The clip may be based on the Padlock Clip® Defect Closure System currently marketed by STERIS Corporation. The clip <NUM> may comprise a plurality of tines for engaging the tissue. Each tine of the clip <NUM> may be blunt or pointed for various purposes, for example, stopping bleeding by compressing the tissue, allowing for optimal healing abilities while still allowing blood flow to the tissue, and holding the tissue together until the site heals itself. <FIG> illustrates the clip <NUM> in the open state, and <FIG> illustrates the clip <NUM> in the closed state. The clip <NUM> is made from resilient materials which can store strain energy, for example, elastic metal alloy such as nitinol. The clip <NUM> can be formed with materials including stainless steel, nitinol, nickel-titanium shape memory alloy, and polymers such as PTFE, polyolefin, and fluorinated ethylene propylene. The clip <NUM> rests in the closed state when no external force is applied, and can be deformed into the open state by application of external force. When in the open state, the clip <NUM> defines a central opening <NUM>. When the external force is no longer applied, the clip <NUM> releases the stored energy and reforms back to the closed state.

<FIG> illustrates the assembly of the pusher <NUM> and the clip <NUM> onto the adaptor <NUM>. The pusher <NUM> is disposed on the adaptor <NUM> by inserting the adaptor <NUM> into the central opening <NUM> defined by the pusher <NUM>. In other words, the pusher <NUM> rides along the outside surface of the adaptor <NUM>, where the pusher <NUM> can slide in the axial direction with respect to the adaptor <NUM>. The at least one driver is attached to the pusher <NUM> by securing onto the at least one knob of the pusher <NUM>. The clip <NUM> is deformed into the open state by external force, and the clip <NUM> in the open state defines a central opening <NUM>. The clip <NUM> is then loaded onto the adaptor <NUM> at a position distal to the pusher <NUM>. The outside surface of the adaptor <NUM> supports the clip <NUM> such that the clip <NUM> is maintained in the open state, which creates a friction against the sliding of the clip <NUM> with respect to the adaptor <NUM> in the axial direction. When a predetermined amount of force is exerted on the clip <NUM> in the distal direction, the clip <NUM> overcomes the friction to slide off the distal edge <NUM> of the adaptor <NUM> and detach from the adaptor <NUM>. <FIG> illustrates the pusher <NUM> and the clip <NUM> assembled onto the adaptor <NUM>. As illustrated in <FIG>, the clip <NUM> contacts the pusher <NUM> such that the clip <NUM> can be pushed in the distal direction when the pusher <NUM> moves in the distal direction.

A person skilled in the art should understand that the clip <NUM> can be loaded onto the inside surface or the outside surface of the adaptor <NUM>, or onto a support surface formed inside the adaptor <NUM>, as long as the clip <NUM> can be maintained in the open position and can slide off the distal edge <NUM> of the adaptor <NUM>. The clip <NUM> and the pusher <NUM> can be disposed on different surfaces of the adaptor <NUM>, where the adaptor <NUM> provides one or more longitudinal slits allowing the pusher <NUM> to contact the clip <NUM> and push the clip <NUM> in the distal direction.

The pusher <NUM> may not contact and push the clip <NUM> in the distal direction. Instead, a clip driver such as a drive wire or a pull thread can be configured to move the clip <NUM> in the distal direction, such that the clip <NUM> can slide off the distal edge <NUM> of the adaptor <NUM>.

Each of the at least one sheath defines a passage for each of the at least one driver. As illustrated in <FIG>, the first driver <NUM> and the second driver <NUM> respectively extends within the first sheath <NUM> and the second sheath <NUM>. The at least one sheath can be reinforced sheaths, such as a spring sheath, formed with various materials including, but not limited to stainless steel, HDPE, PTFE, and nitinol. The at least one sheath may be coated inside or outside to improve the deployment of the device. A heat shrink may be applied over the top of the at least one sheath to increase strength along lengths where the sheath transitions from flexible to stiffer segments of the assembly.

The proximal end of the at least one sheath can be coupled with the clip deployment handle <NUM>. The distal end of the at least one sheath is attached to the adaptor <NUM> by, for example, heat staking, gluing, welding, or overmolding. As illustrated in <FIG>, the first sheath <NUM> and the second sheath <NUM> are attached to the adaptor <NUM> respectively by the overmolding <NUM> and the overmolding <NUM>. As illustrated in <FIG>, the overmolding <NUM> and the overmolding <NUM> may be integrally formed with the lumen <NUM> by one step of overmolding. Each of the at least one sheath can be separately attached to the adaptor <NUM>, either before or after the lumen <NUM> is formed. A person skilled in the art should understand that the at least one sheath can be attached to any portion of the adaptor <NUM>, such as the inside surface of the adaptor <NUM>, as long as the at least one sheath does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>. The at least one sheath may penetrate the adaptor <NUM>, such that the at least one sheath extends through a hole formed on the adaptor <NUM>. In addition, a person skilled in the art should understand that the at least one sheath may not be attached with the adaptor <NUM>. Instead, the at least one sheath may be attached with any component of the endoscopic device or the endoscopic resection assembly <NUM>, as long as the at least one sheath does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>.

The at least one driver comprises endoscopic tools for pushing the pusher <NUM> in the distal direction. As illustrated in <FIG>, the at least one driver comprises the first driver <NUM> and the second driver <NUM> which are drive wires respectively extending within the first sheath <NUM> and the second sheath <NUM>. The proximal end of the at least one driver may operatively couple with the clip deployment handle <NUM>. The clip deployment handle <NUM> is configured to actuate the at least one driver, such that the at least one driver advances with respect to the at least one sheath.

The catheter <NUM> is a catheter configured for allowing the operation of the cutting device <NUM> between the open state and the closed state. The catheter <NUM> may define a passage for the snare drive cable <NUM> of the cutting device <NUM>. The catheter <NUM> can be a sheath formed with various materials including, but not limited to stainless steel, HDPE, PTFE, and nitinol. The catheter <NUM> and the at least one sheath, for example the first sheath <NUM> and the second sheath <NUM>, may be contained within the same catheter subassembly, such as in a multilumen catheter sheath. The proximal end of the catheter <NUM> may be coupled with the handle <NUM>. As illustrated in <FIG>, the catheter <NUM> is coupled with the adaptor <NUM> by slip fitting into the lumen <NUM> of the adaptor <NUM>. A person skilled in the art should understand that the catheter <NUM> may be coupled to any portion of the adaptor <NUM>, such as the inside surface of the adaptor <NUM>, as long as the catheter <NUM> does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>. The catheter <NUM> may penetrate the adaptor <NUM>, such that the catheter <NUM> extends through a hole formed on the adaptor <NUM>. In addition, a person skilled in the art should understand that the catheter <NUM> can be fixed with the adaptor <NUM>, or be detached from the adaptor <NUM>, as long as the catheter <NUM> does not interfere with the operations of the endoscopic device and other components of the endoscopic resection assembly <NUM>.

Additionally, a marking device, such as a probe, can be provided in the endoscopic device to outline the perimeter of the target tissue to be resected.

In operation (not according to the invention), the endoscopic resection assembly is mounted on an endoscopic device through the adaptor <NUM> configured to attach with the endoscopic device (e.g., Olympus®, Fujinon®, or Pentax® endoscopes) by, for example, press fitting. The operator guides the endoscope into the GI tract and to the lesion that needs to be resected. The perimeter of the target tissue to be resected can be marked with a marking device, such as a probe, provided in the endoscopic device.

In a next step (not according to the invention), the target tissue to be resected is recruited into the tissue chamber channel defined by the adaptor <NUM>. In cases where the target tissue is a lesion, some extra tissue surrounding the lesion in addition to the lesion can be recruited into the adaptor <NUM>, which ensures that the entire lesion can be resected and removed. An endoscopic grasper may be provided in the adaptor <NUM>. The endoscopic grasper may advance out of the adaptor <NUM>, grasp a tissue, and pull the tissue into the adaptor <NUM>. Tissue can be recruited into the adaptor <NUM> via suction or by other means and endoscopic tools. When the perimeter of the target tissue is initially marked with a marking device, the marked edges can help the operator in determining whether the target tissue is entirely pulled into the cap.

In a next step (not according to the invention), the clip <NUM> is deployed over the tissue. The clip deployment handle <NUM> may be actuated to advance the at least one driver with respect to the at least one sheath. Through the attachment of the pusher <NUM> with the at least one driver, a force may be exerted on the pusher <NUM> in the distal direction. As result, as illustrated in <FIG>, the pusher <NUM> moves in the distal direction with respect to the adaptor <NUM>. The clip <NUM> may be loaded on the adaptor <NUM> at a position distal to the pusher <NUM> and maintained in the open state. As the pusher <NUM> moves in the distal direction, the distal surface of the pusher <NUM> may contact the clip <NUM> to exert a force sufficient to overcome the friction between the clip <NUM> and the adaptor <NUM>. As result, the clip <NUM> slides against the outside surface of the adaptor <NUM> in the distal direction. As the clip <NUM> slides off the distal edge <NUM> of the adaptor <NUM>, as illustrated in <FIG>, the support provided by the outside surface of the adaptor <NUM> becomes insufficient to maintain the clip <NUM> in the open state. Due to the energy stored in the clip <NUM>, the clip <NUM> reforms toward the closed state where the tines of the clip <NUM> engage onto the tissue recruited into the adaptor <NUM>. In cases where the target tissue is a lesion, the clip <NUM> may engage onto some extra or marginal tissue surrounding the lesion which ensures that the entire lesion can be resected and removed.

The clip deployment handle <NUM> may be further actuated to advance the at least one driver, which further moves the pusher <NUM> in the distal direction. The clip deployment handle <NUM> is actuated until the pusher <NUM> sits directly on top of the clip <NUM>. <FIG> illustrates the clip <NUM> and the pusher <NUM> in the deployed position where the tissue is not shown. As illustrated in <FIG>, when the pusher <NUM> is in the deployed position, at least a portion of the pusher <NUM> is distal to the adapter <NUM>. In other words, at least a portion of the pusher <NUM> in the deployed position extends beyond the edge <NUM> of the adaptor <NUM>. For example, the pusher <NUM> in the deployed position may extend beyond the edge <NUM> of the adaptor <NUM> by <NUM> to <NUM>.

In a next step (not according to the invention), the tissue is resected by operating the cutting device <NUM>. The cutting device <NUM> is operated from the open state toward the closed state while cutting the tissue. The cutting device <NUM> is operated from the closed state toward the open state, and then operated from the open state toward the closed state while cutting the tissue. The handle <NUM> is actuated to retract the snare drive cable <NUM> with respect to the catheter <NUM>, which pulls the snare loop <NUM> into the catheter <NUM>. As result, the snare loop <NUM> is contracted such that the cutting device <NUM> operates from the open state toward the closed state. The cutting device <NUM> is removably coupled to the pusher <NUM> where the snare loop <NUM> is accommodated in the passage defined by the at least one retainer of the pusher <NUM>. When contracted, the snare loop <NUM> escapes from the passage through the slit defined by the at least one retainer, and moves radially inward into the central opening <NUM> defined by the pusher <NUM>. As such, the cutting device <NUM> is removed from the pusher <NUM>, and the tissue recruited in the adaptor <NUM> is resected by the snare loop <NUM> moving radially inward. Diathermic energy may be applied through the snare loop to assist the resection. The amount of tissue that can be resected is affected by the axial distance between the distal end of the pusher <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled. As illustrated in FIGS. 2D and 3A-3C, the cutting device <NUM> is coupled to the top surface of the pusher <NUM>. As such, the axial distance between the distal end of the pusher <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled is equivalent to the stack height of the pusher <NUM>, that is, the distance between the top surface and the bottom surface of the pusher <NUM>. When the pusher <NUM> has a large stack height, there is a large axial distance between the distal end of the pusher <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled. Therefore, the resection will be shallow, with less tissue being resected by the cutting device <NUM> and more tissue remaining within the central opening <NUM> defined by the pusher <NUM> after resection. In contrast, when the pusher <NUM> has a small stack height, there is a small axial distance between the distal end of the pusher <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled. Therefore, the resection will be deep, with more tissue being resected by the cutting device <NUM> and less tissue remaining within the central opening <NUM> defined by the pusher <NUM> after resection. The axial distance between the distal end of the pusher <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled can be varied and adjusted, for example by adjusting the stack height of the pusher <NUM>, in order to ensure there is an appropriate amount of tissue to be resected as well as an appropriate amount of tissue remaining within the central opening <NUM> defined by the pusher <NUM> after resection. After resection, some tissue remains at the resection site on the proximal side of the clip <NUM> due to the axial distance between the clip <NUM> and the position on the pusher <NUM> where the cutting device <NUM> is coupled, which ensures that the clip <NUM> remains engaged with the tissue to close the defect. When the snare loop <NUM> is accommodated in the passages positioned at <NUM> to <NUM> from the distal surface of the pusher <NUM>, about <NUM> to <NUM> of tissue will remain on the proximal side of the clip <NUM> after resection. The endoscopic resection assembly, except for the clip <NUM>, is then removed from the GI tract. For a less traumatic removal process, the clip deployment handle <NUM> can be actuated to retract the at least one driver which moves the pusher <NUM> in the proximal direction and back onto the adaptor <NUM>.

Claim 1:
An endoscopic resection assembly (<NUM>), comprising:
(a) an adaptor (<NUM>), configured to couple to an endoscopic device;
(b) a pusher (<NUM>), disposed on the adaptor (<NUM>);
(c) at least one driver, configured to move the pusher (<NUM>) in a distal direction with respect to the adaptor (<NUM>); and
(d) a cutting device (<NUM>), removably coupled to the pusher (<NUM>),
wherein the cutting device (<NUM>) is configured to be removed from the pusher (<NUM>) when at least a portion of the pusher is distal to the adaptor (<NUM>),
wherein the adaptor (<NUM>) is configured to be loaded with a clip (<NUM>), wherein the clip (<NUM>) is configured to operate between an open state and a closed state wherein the clip (<NUM>) is configured to be loaded on the adaptor (<NUM>) in the open state at a position distal to the pusher (<NUM>), wherein the clip (<NUM>) is configured to be pushed by the pusher (<NUM>) to slide off the distal edge (<NUM>) of the adaptor (<NUM>) so that the clip (<NUM>) is configured to be released from the adaptor (<NUM>) and to engage onto a tissue before the cutting device (<NUM>) is removed from the pusher (<NUM>).