Patent Description:
The present disclosure relates to endoscopic devices and, in particular, relates to endoscopic clipping devices for treating tissue along the gastrointestinal tract.

During endoscopic gastrointestinal (GI) procedures, the patient may be at risk of perforation of a wall of the Gl tract, or may require closure of the GI tract wall as part of the procedure. Hemostasis clips may be used for hemostasis of, for example, mucosal/sub-mucosal defects, bleeding ulcers, arteries, polyps, diverticula, along with closure of luminal tract perforations. Depending on the size of the defect, multiple clips may be required. <CIT> describes an apparatus for deployment of a hemostatic clip. The apparatus includes a clip assembly releasably coupled to a distal portion of a shaft, wherein the clip assembly includes a capsule releasably coupled to the shaft, clip arms slidably received within the capsule and cooperating with the capsule to provide a first user feedback indicating a decision configuration of the clip assembly and a yoke having a proximal and distal portion and being slidably received within the capsule. A second control wire extends from the handle assembly and is coupled to a proximal end of the second portion to move the clip assembly between open and closed configurations. <CIT> discloses a system for treating tissue. The system has a clip assembly including a pair of clip arms, proximal ends of the clip arms slidably received within a channel of a capsule to be moved between a tissue receiving configuration and a tissue clipping configuration. The assembly includes an applicator including a catheter and a control member extending therethrough, a distal end of the control member configured to be connected to the clip arms to move the clip assembly between the tissue receiving and tissue clipping configurations. A coupler is releasably coupled to proximal ends of the clip arms and configured to be coupled to the distal end of the control member, the coupler configured to yield when a proximal force exerted on the coupler via the control member exceeds a first predetermined threshold value to disengage the clip arms to deploy the clip assembly. <CIT> discloses a system for treating tissue. The system includes an applicator including a catheter and a control member extending therethrough, the control member longitudinally movable relative to the catheter and including an abutment structure proximate a distal end thereof, and a clip assembly releasably coupleable to a distal end of the applicator. The clip assembly includes a pair of clip arms, a proximal end of each of the clip arms slidably received within a channel of a capsule and configured to be releasably coupled to the distal end of the control member so that the clip arms are movable relative to the capsule between a tissue receiving configuration and a tissue clipping configuration. The capsule includes proximal tabs movable between a biased non-engaging and an engaging configuration, in which the proximal tabs engage an engaging portion of the lumen of the catheter, when the abutment structure is received within the capsule. <CIT> describes a clip member of substantially a figure "eight" shape which is detachably attached to an instrument body. The instrument body has an outer flexible tube, an actuating tubular member inserted into the outer tube, and a wire inserted into the actuating tubular member. A holder is detachably mounted through a guide member to the forward end portion of the actuating member. To the forward end of the wire is secured a hook member for anchoring the clip member. A pair of clamping portions of the clip member is opened by forcefully engaging a pair of offset portions of the clip member with the inner surface of the holder and closed by forcefully engaging a pair of intersecting portions with the inner surface of the holder.

The presently claimed invention relates to a device for treating a target tissue according to claim <NUM>. Further developments of the presently claimed invention are defined in the dependent claims.

The present disclosure may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present disclosure is directed to an endoscopic clipping device for treating tissue perforations, defects and/or bleeds. In some cases, a shorter deployed clip may be preferred to improve visualization of the target site and to allow better maneuverability when placing multiple clips. Exemplary embodiments of the present disclosure describe a clip comprising clip arms, proximal ends of which are slidably received within a capsule to move the clip between an open configuration and a closed configuration to clip a target tissue, as desired. As the clip is deployed over the target tissue in the closed configuration, the capsule collapses to reduce a length of the deployed clip, improving visibility of a target site and maneuverability when placing multiple clips. It should be noted that the terms proximal and distal, as used herein, are intended to refer to a direction toward (proximal) and away from (distal) a user of the device.

As shown in <FIG>, a clipping device <NUM> for treating tissue defects comprises a clip <NUM> including a pair of clip arms <NUM>, proximal ends <NUM> of which are slidably received within a capsule <NUM> so that the clip <NUM> may move between an open configuration, in which distal ends <NUM> of the clip arms <NUM> are separated from one another, and a closed configuration, in which the distal ends <NUM> are drawn toward one another. The capsule <NUM> further comprises a longitudinal body <NUM> and a cap <NUM> coupled to one another and movable relative to one another from a pre-deployed configuration to a deployed configuration. In one embodiment, the cap <NUM> may be coupled to the longitudinal body <NUM> via, for example, a shear pin <NUM>, which breaks or separates to move the capsule from the pre-deployed to the deployed configuration. As the capsule <NUM> is moved from the pre-deployed to the deployed configuration, the cap <NUM> moves relative to the longitudinal body <NUM> to reduce a length of the capsule <NUM> upon deployment. The device <NUM> is releasably coupled to a proximal portion <NUM> facilitating insertion of the device <NUM> to a target site, connecting the clip <NUM> to actuators accessible to a user (i.e., outside the body) to permit the user to control movement of the device <NUM> between the open and closed configurations and to deploy the device clip <NUM> over target tissue. The proximal portion <NUM> may include, for example, a flexible shaft <NUM> extending from a proximal end connected to a handle member (not shown) that remains outside the body, the handle including controls for moving and deploying the device <NUM> to a distal end <NUM> releasably coupled to a proximal end <NUM> of the capsule <NUM>. The proximal portion <NUM> also includes a control member <NUM> extending from a proximal end connected to the controls of the handle member to a distal end <NUM> connected to the proximal ends <NUM> of the clip arms <NUM>.

As described above, the capsule <NUM> includes the longitudinal body <NUM> and the cap <NUM>. The longitudinal body <NUM> extends from the proximal end <NUM> to a distal end <NUM> and includes a channel <NUM> extending therethrough. In one embodiment, the proximal end <NUM> is configured to be releasably coupled to the distal end <NUM> of the flexible shaft <NUM>. For example, the proximal end <NUM> may include tabs <NUM> that are crimped radially inward to engage a corresponding portion of a bushing at the distal end <NUM> of the flexible shaft <NUM>. The longitudinal body <NUM> may also include locking windows <NUM> extending laterally through a wall thereof or other structures for engaging locking tabs <NUM> of the clip arms <NUM>, as will be described in further detail below.

In one embodiment, the cap <NUM> is mounted over the distal end <NUM> so that the cap <NUM> is movable relative to the longitudinal body <NUM> from the pre-deployed to the deployed configuration. The cap <NUM> also extends longitudinally from a proximal end <NUM> to a distal end <NUM> with a channel <NUM> extending longitudinally therethrough so that channels <NUM>, <NUM> of the cap <NUM> and the longitudinal body <NUM> are aligned to permit the clip arms <NUM> to slide longitudinally therein. In the pre-deployed configuration, the cap <NUM> is in a distal-most position relative to the longitudinal body <NUM>. As the capsule <NUM> is moved from the pre-deployed to the deployed configuration, the cap <NUM> moves proximally relative to the longitudinal body <NUM> so that a length of the capsule <NUM> in the deployed configuration is shorter than a length of the capsule <NUM> in the pre-deployed configuration. In one embodiment, the distal end <NUM> of the cap <NUM> includes a shoulder <NUM> configured to engage the distal end <NUM> of the longitudinal body <NUM> to prevent the distal end <NUM> of the longitudinal body <NUM> from moving distally therepast. In other words, when the shoulder <NUM> engages the distal end <NUM> of the longitudinal body <NUM>, the cap <NUM> is in a proximal-most position relative to the longitudinal body <NUM> and defines a minimum length of the capsule <NUM>.

The cap <NUM> may be coupled to the distal end <NUM> of the longitudinal body <NUM> in any of a variety of ways. In one embodiment, the cap <NUM> may be overmolded to the longitudinal body <NUM>. In one example, as shown in <FIG>, the cap <NUM> is overmolded to the distal end <NUM> of the longitudinal body <NUM> via a shear pin <NUM>, in the pre-deployed configuration. The shear pin <NUM> is configured to break and/or separate when a predetermined force is exerted thereon. In one embodiment, when the clip arms <NUM> are drawn proximally relative to the capsule <NUM> to lock and deploy the clip <NUM>, as will be described in further detail below, a portion of the one or both clip arms <NUM> engages the distal end <NUM> of the cap <NUM> so that a proximal force is exerted thereon. The proximal force exerted on the cap <NUM> breaks the shear pin <NUM> so that the cap <NUM> is freed to move proximally with respect to the longitudinal body <NUM>, from the pre-deployed to the deployed configuration.

Each of the clip arms <NUM> extends from the proximal end <NUM> to the distal end <NUM>. As described above, proximal portions of the clip arms <NUM> are slidably received within the channels <NUM>, <NUM> of the longitudinal body <NUM> and the cap <NUM> of the capsule <NUM>. In some embodiments, the proximal ends <NUM> of the clip arms <NUM> are slidably received within the longitudinal body <NUM> to move the clip <NUM> between the open and closed configurations. For example, as described above, the proximal ends <NUM> of the clip arms <NUM> may be coupled to the control member <NUM> (directly or indirectly) so that the clip arms <NUM> may be moved between the open and closed configurations via manipulation of the control member <NUM>. In one embodiment, the clip arms <NUM> are biased toward the open configuration so that, in the closed configuration, the clip arms <NUM> are constrained toward one another via an interior surface of the cap <NUM> and/or the longitudinal body <NUM>. When the clip arms <NUM> are moved distally to extend further out of the capsule <NUM>, the clip arms <NUM> revert to their biased open configuration.

Each of the clip arms <NUM> also includes an engaging feature <NUM> configured to engage a portion of the cap <NUM> to exert a proximal force thereon when the clip arms <NUM> are drawn proximally with respect to the capsule <NUM>. In one embodiment, as shown in <FIG>, the engaging features <NUM> extend from a portion of the clip arms <NUM> so that, when the clip arms <NUM> are drawn proximally relative to the capsule <NUM>, the engaging features <NUM> abut a portion of a distal face <NUM> of the cap <NUM>. The engaging features <NUM> are positioned along the clip arms <NUM> so that, when the engaging features <NUM> engage the cap <NUM>, the clip arms <NUM> are drawn toward the closed configuration. In one example, the engaging features <NUM> are configured as wings extending from longitudinal edges of the clip arms <NUM>.

Proximal ends <NUM> of the clip arms <NUM> also include locking tabs <NUM> extending therefrom. The proximal ends <NUM> in this embodiment are biased outward, away from a centerline of the capsule <NUM>, but are restrained via the distal end <NUM> of the control member <NUM> until the clip <NUM> is being deployed. As will be described in further detail below, when it is desired to lock the clip <NUM> in the closed configuration, the clip arms <NUM> are moved proximally relative to the capsule <NUM> until the proximal ends <NUM> of the clip arms <NUM> are released from the control member <NUM> and the locking tabs <NUM> are permitted to spring outward and engage the locking windows <NUM> of the longitudinal body <NUM>.

According to an exemplary method utilizing the device <NUM>, the clip <NUM> is inserted through, for example, a working channel of an endoscope to a target site within a body while the handle member remains exterior to the body. The clip <NUM> is inserted through the working channel in the closed configuration. Once the clip <NUM> has reached the target site, the clip arms <NUM> are extended distally out of the capsule <NUM> and move under their natural bias toward the open configuration so that target tissue may be received between the clip arms <NUM>. The clip <NUM> may be moved between the open and closed configurations by extending the control member <NUM> distally or withdrawing it proximally until a desired portion of target tissue is positioned between the clip arms <NUM>, as desired. At this point, the clip <NUM> is drawn into the closed configuration to grip this portion of target tissue between the distal ends <NUM> of the clip arms <NUM> as desired. The clip <NUM> may be moved toward the locked configuration by, for example, drawing the control member <NUM> further proximally relative to the capsule <NUM> until the engaging features <NUM> engage the cap <NUM>, as described above, exerting a proximal force on the cap <NUM> to break, separate or otherwise cause the shear pin <NUM> to fail. Upon breaking/separating of the shear pin <NUM>, the cap <NUM> moves proximally relative to the longitudinal body <NUM> from the pre-deployed configuration to the deployed configuration, collapsing the capsule <NUM> and reducing a length of the capsule <NUM>.

When the shoulder <NUM> of the cap <NUM> contacts the distal end <NUM> of the longitudinal body <NUM> and prevents the cap <NUM> from moving further proximally relative to the longitudinal body <NUM>, the clip <NUM> is locked and deployed. According to one example, when the shoulder <NUM> engages the longitudinal body <NUM>, the proximal force on the control member <NUM> causes the control member <NUM> to release from the proximal ends <NUM> of the clip arms <NUM>, allowing the proximal ends <NUM> to revert to their biased configuration so that the locking tabs <NUM> engage the locking windows <NUM>, thereby locking the clip <NUM> in the collapsed, closed configuration. The control member <NUM> is drawn proximally until an enlarged portion <NUM> at the distal end <NUM> of the control member <NUM> is positioned within the proximal end <NUM> of the longitudinal body <NUM> of the capsule <NUM> to move the inwardly crimped tabs <NUM> outward (i.e., away from a centerline of the capsule <NUM>), out of engagement with, for example, the bushing at the distal end <NUM> of the flexible shaft <NUM>. Further proximal motion of the control member <NUM> separates the control member <NUM> from the clip <NUM>, freeing the clip <NUM> from the proximal portion of the device <NUM> and freeing it to remain in the body as the rest of the device <NUM> is removed from the body.

Although the exemplary embodiments show and describe a specific deployment mechanism, it will be understood by those of skill in the art that the clip <NUM> may be deployed via any of a number of deployment mechanisms so long as the capsule <NUM> collapses to reduce a length thereof during the deployment process. Specifically, as described above, the capsule <NUM> is collapsed via the proximal motion of the cap <NUM> relative to the longitudinal body. Although the exemplary embodiment describes and shows mounting of the cap <NUM> over the distal end <NUM> of the longitudinal body <NUM> in the pre-deployed configuration via a shear pin <NUM>, it will be understood by those of skill in the art that the cap <NUM> may be temporarily fixed relative to the longitudinal body <NUM> in the pre-deployed configuration and moved toward the deployed configuration via any of a number of mechanisms.

For example, as shown in <FIG>, a capsule <NUM> may be substantially similar to the capsule <NUM> described above, and may be utilized in place of the capsule <NUM> in the device <NUM>. Similarly to the capsule <NUM>, the capsule <NUM> includes a cap <NUM> mounted over a distal end <NUM> of a longitudinal body <NUM> and movable relative thereto from a pre-deployed configuration to a deployed configuration. The cap <NUM> and the longitudinal body <NUM> may be substantially similar to the cap <NUM> and longitudinal body <NUM> described above with respect to the capsule <NUM>. Rather than being mounted over the longitudinal body in the pre-deployed configuration via a shear pin, however, the cap <NUM> is coupled to the longitudinal body <NUM> via a pin <NUM> and slot <NUM>.

In one embodiment, a distal portion of the longitudinal body <NUM> includes the slot <NUM> extending longitudinally through a wall thereof. The pin <NUM> extends from an interior surface of the cap <NUM> and through the slot <NUM> to couple the cap <NUM> to the longitudinal body <NUM>. In a pre-deployed configuration, the pin <NUM> extends through a distal portion <NUM> of the slot <NUM> while in the deployed configuration, the pin <NUM> extends through the proximal portion <NUM> of the slot <NUM>. The distal and proximal portions <NUM>, <NUM> of the slot <NUM> are sized and shaped to correspond to a size and shape of the pin <NUM> received therein. A middle portion <NUM> of the slot <NUM> connecting the distal and proximal portions <NUM>, <NUM> has a width smaller than a width of each of the distal and proximal portions <NUM>, <NUM>. In other words, where the pin <NUM> is cylindrical, a width of the middle portion <NUM> is smaller than a diameter of the pin <NUM> so that, to be moved from the pre-deployed to the deployed configuration, a predetermined force must be exerted on the pin <NUM>, causing one of the pin <NUM> and/or the middle portion <NUM> to elastically deform allowing the pin <NUM> to slide along the middle portion <NUM> from the distal portion <NUM> to the proximal portion <NUM>.

Claim 1:
A device (<NUM>) for treating a target tissue, comprising:
a clip (<NUM>) including a capsule (<NUM>, <NUM>) extending longitudinally from a proximal end to a distal end and including a channel (<NUM>) extending therethrough, proximal ends of a pair of clip arms (<NUM>) slidably received within the channel (<NUM>) so that the pair of clip arms (<NUM>) are movable between an open configuration, in which distal ends (<NUM>) thereof are separated from one another, and a closed configuration, in which the distal ends (<NUM>) thereof are moved toward one another, the capsule (<NUM>, <NUM>) further including a cap (<NUM>, <NUM>) coupled to a distal end of a longitudinal body (<NUM>, <NUM>) so that, when a predetermined force is exerted on the cap (<NUM>, <NUM>) via engaging features (<NUM>) of the clip arms (<NUM>), the cap (<NUM>, <NUM>) is moved from a pre-deployed configuration to the deployed configuration, in which the cap (<NUM>, <NUM>) is moved proximally relative to the longitudinal body (<NUM>, <NUM>) to reduce a length of the capsule (<NUM>, <NUM>); and
a proximal portion (<NUM>) configured to permit insertion of the clip (<NUM>) through a working channel of an endoscope, the proximal portion including a flexible shaft (<NUM>) extending from a proximal end to a distal end configured to be releasably coupled to the proximal end of the capsule (<NUM>, <NUM>) and a control member (<NUM>) extending through the flexible shaft to a distal end releasably coupled to proximal ends of the clip arms (<NUM>) so that moving the control member longitudinally relative to the flexible shaft moves the clip arms (<NUM>) between the open and the closed configurations.