Patent Description:
During endoscopic gastrointestinal (GI) procedures, the patient may be at risk of perforation of a wall of the GI 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 a ligating device comprising a clip having arms for holding tissue, a press tube, and a tightening member for opening the arms of the clip when fitted on the clip. The device comprises a connection member that is inserted in the press tube and is joined to the clip, and projections, as connection portions, for holding the arms of the clip in a closed state when the clip and the press tube are joined together.

The present disclosure relates to a device for treating tissue, comprising a capsule extending longitudinally from a proximal end to a distal end and including a channel extending therethrough along with first and second clip arms, proximal ends of which are received within the channel so that the first and second clip arms are movable relative to one another between an open configuration and a closed configuration. A deployment mechanism including a tension member connected to a proximal end of the first and second clip arms, a yoke releasably coupled to the tension member and longitudinally movable relative to the capsule to move the first and second clip arms between the open and closed configurations. The tension member and yoke are configured to separate from one another to release the device from a proximal portion thereof, in response to a predetermined proximal force relative to the tension member. A locking mechanism is coupled to the deployment mechanism and including a pair of locking fingers configured to engage a corresponding locking feature of the capsule to lock the first and second clip arms in the closed configuration, when the yoke is separated from the tension member. The locking mechanism is separate from the one-piece clipping element.

In an embodiment, the first and second clip arms may be defined via a one-piece clipping element extending from a first end to a second end and including a bend along a portion thereof, the bend extending along a midpoint of the one-piece clipping element so that a length of the first and second clip arms substantially correspond.

In an embodiment, a distal end of tension member may be connected to the proximal end of the clip arms via a pin extending diametrically across the distal end of the tension member and through a substantially rounded space formed at the proximal end of the clip arms via the bend along the one-piece clipping element.

In an embodiment, the locking mechanism may include a ring coupled to the distal end of the tension member via the pin, the pair of locking fingers extending proximally from the ring.

In an embodiment, the locking fingers may be biased radially outward and include locking structures extending from proximal ends thereof.

In an embodiment, the yoke may include a pair of overhangs constraining the proximal ends of the locking fingers against the yoke and preventing the locking structures from engaging the locking features of the capsule until the yoke is separated from the tension member.

In an embodiment, the capsule may have a length ranging from between approximately <NUM> to <NUM>.

In an embodiment, the first and second clip arms may be biased toward the open configuration so that, when the first and second clip arms are drawn proximally into the capsule, the first and second clip arms are constrained toward the closed configuration, and when the first and second clip arms are moved distally out of the capsule, the first and second clip arms are permitted to revert to their biased open configuration.

The present disclosure also relates to a clipping device, comprising a clip including a capsule extending longitudinally from a proximal end to a distal end and including a channel extending therethrough. Proximal ends of first and second clip arms are slidably received within the channel of the capsule to move the first and second clip arms relative to one another between an open configuration and a closed configuration. A deployment mechanism includes a tension member connected to a proximal end of the first and second clip arms. A yoke is releasably coupled to the tension member and is couplable to a control member, which is movable relative to the capsule to move the first and second clip arms between the open and closed configurations. The tension member and yoke are configured to separate in response to a predetermined proximal force relative to the tension member. A locking mechanism is coupled to the deployment mechanism and includes a pair of locking fingers configured to engage a corresponding locking feature of the capsule to lock the first and second clip arms in the closed configuration, when the yoke is separated from the tension member. A proximal portion is releasably coupled to the proximal end of the capsule so that, upon separation of the yoke from the tension member, the clip is released from the proximal portion and deployed in a body over the target tissue.

In an embodiment, the first and second clip arms may be defined via a one-piece clipping element extending from a first end to a second end and including a bend along a portion thereof, the bend extending along a midpoint of the one-piece clipping element so that a length of the first and second clip arms substantially correspond.

In an embodiment, a distal end of the tension member may be connected to the proximal end of the clip arms via a pin extending diametrically across the distal end of the tension member and through a substantially rounded space formed at the proximal end of the clip arms via the bend along the one-piece clipping element.

The present disclosure also relates to a method for treating target tissue. A clip device is inserted through a working channel of an endoscope to a target site within a body until a clip of the clip device extends distally past a distal end of the working channel. The clip device includes a capsule and a pair of clip arms, proximal ends of which are slidably received within the capsule. The clip device is moved between an open configuration and a closed configuration until a selected target tissue is gripped between the first and second ends of the one-piece clipping element, the first and second clip arms moved between the open and closed configurations via a control wire coupled to a yoke that is releasably coupled to a tension member connected to the first and second clip arms. The clip device is locked in the closed configuration, once the target tissue is gripped as desired, by applying a predetermined proximal force along the control member to separate the yoke from the tension member, which permits locking fingers of a locking mechanism to engage corresponding locking features of the capsule.

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 internal tissue perforations, defects and/or bleeds. In some embodiments, 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 including clip arms defined via a one-piece element slidable within a capsule to move the clip between an open configuration and a closed configuration to clip target tissue, as desired. The one-piece element is connected to a separate deployment mechanism and locking mechanism to decrease a length of a deployed clip relative to other conventional clip designs which include capsules. It will be understood by those of skill in the art that the terms proximal and distal as used herein, are intended to refer to a direction toward and away from, respectively, a user of the device.

As shown in <FIG>, a clip device <NUM> according to an exemplary embodiment of the present disclosure comprises a clip <NUM> including a one-piece element <NUM> defining a pair of clip arms <NUM> received within a capsule <NUM> to move the clip arms <NUM> 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 to grip tissue. In embodiments, the one-piece element <NUM> extends from a first end <NUM> to a second end <NUM> and is bent, for example, at a joint or midpoint <NUM> to define the clip arms <NUM>. The midpoint <NUM> is connected to a deployment mechanism <NUM> including a tension member <NUM> and a yoke <NUM>, which are slidably received within the capsule <NUM> to move the clip arms <NUM> between the open and the closed configuration.

A locking mechanism <NUM> is coupled to the one-piece element <NUM> and the deployment mechanism <NUM> so that, when the clip <NUM> is deployed over target tissue in a body, the clip <NUM> is locked in the closed configuration. In one embodiment, as shown in <FIG>, the clip <NUM> is releasably coupled to an elongated proximal portion <NUM> of the device <NUM> sized to facilitate insertion of the clip <NUM> through a working channel of an endoscope to a target site within the body while a proximal end remains outside the body accessible to a user. The proximal portion <NUM> may include, for example, a handle member <NUM> including actuators <NUM> enabling a user to control movement and deployment of the clip <NUM> and a flexible shaft <NUM> extending distally from the handle member <NUM> to the clip <NUM>, a distal end <NUM> of the flexible shaft <NUM> being releasably coupled to the clip <NUM> via, for example, a bushing <NUM>. The user manipulates the actuators <NUM> to move a control member <NUM> that extends from the handle member <NUM>, through the flexible shaft <NUM> to connect to the clip arms <NUM> to control movement of the clip arms <NUM> between the open and closed configurations.

The capsule <NUM> extends from a 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 proximal portion of the device via tabs <NUM> at the proximal end <NUM> of the capsule <NUM>, which may be crimped radially inward to engage a corresponding portion of the proximal portion. The capsule <NUM> also includes, for example, locking features formed in a capsule wall such as, for example, locking windows <NUM> that extend laterally through the capsule wall for engaging a portion of the locking mechanism <NUM>, as will be described in further detail below.

In one embodiment, the capsule <NUM> may have a length ranging from between <NUM> to <NUM>. The capsule <NUM> of this embodiment is substantially shorter than capsule lengths of some conventional clips, which may have lengths ranging from between <NUM> to <NUM>. It will be understood by those of skill in the art that the one-piece design of the clip arms <NUM> and the separate locking mechanism <NUM>, which will be described in further detail below, permits the capsule <NUM> to have a shorter length relative to some existing clips without sacrificing an opening width of the clip arms <NUM>.

As described above, the clip arms <NUM> are formed from a one-piece element <NUM> which extends along a length from the first end <NUM> to the second end <NUM> and is bent at, for example, the midpoint <NUM> so that the clip arms <NUM> extend along a portion of a length extending from opposite sides of the midpoint <NUM>, e.g., proximal of the first and second ends <NUM>, <NUM>. Thus, the first and second ends <NUM>, <NUM> of the one-piece element <NUM> correspond to the distal ends <NUM> of the clip arms <NUM>. The midpoint <NUM> is connected to the deployment mechanism <NUM> which is slidably received within the channel <NUM> of the capsule <NUM> so that the clip arms <NUM> are movable between the open and the closed configurations.

In one embodiment, the clip arms <NUM> are biased toward the open configuration so that, when advanced distally out of the capsule <NUM>, the clip arms <NUM> move apart from one another into the open configuration under their natural bias. When the arms <NUM> are drawn proximally into the capsule <NUM>, the clip arms <NUM> are constrained by the wall of the capsule <NUM> and drawn together into the closed position with the distal ends <NUM> adjacent one another. Those skilled in the art will understand that any number of other mechanisms for opening and closing the clip arms <NUM> may be employed. It will also be understood by those of skill in the art that although the exemplary embodiments show and describe a one-piece element <NUM> including a bend to form clip arms <NUM>, in an alternative embodiment, proximal ends of clip arms may be attached to one another such that the proximal ends are connectable to the tension member <NUM>.

The clip arms <NUM> of this embodiment also include engaging features <NUM> extending therefrom and configured to engage a portion of the capsule <NUM> so that, when the engaging features <NUM> engage the capsule <NUM>, the clip arms <NUM> are prevented from being moved further proximally into the capsule <NUM>. In one embodiment, the engaging features <NUM> extend laterally outward from portions of the clip arms <NUM> so that portions of the clip arms <NUM> distal of the engaging features <NUM> have a greater width than portions of the clip arms <NUM> proximal of the engaging features <NUM>. The portions of the clip arms <NUM> extending proximal of the engaging features <NUM> are sized to permit these portions of the clip arms <NUM> to be drawn proximally into the capsule <NUM>.

As the proximal portions of the clip arms <NUM> are drawn proximally into the capsule <NUM>, the engaging features <NUM> abut a portion of a distal face <NUM> of the capsule <NUM> preventing the clip arms <NUM> from being drawn further proximally into the capsule <NUM>. The engaging features <NUM> are positioned along the length of the clip arms <NUM> so that, at the point where the engaging features <NUM> have engaged the capsule <NUM>, the clip arms <NUM> have been drawn sufficiently proximally into the capsule <NUM> to draw the clip arms <NUM> together into the closed configuration. In one example, the engaging features <NUM> are configured as wings extending laterally from longitudinal edges of the clip arms <NUM>.

The tension member <NUM> extends from a proximal end <NUM> configured to be releasably coupled to the yoke <NUM> to a distal end <NUM> attached to the midpoint <NUM> of the one-piece element <NUM> via, for example, a pin <NUM>. In one embodiment, the distal end <NUM> extends over the midpoint <NUM> such that the pin <NUM>, which extends diametrically across the distal end <NUM>, is received within a substantially rounded space at a proximal end <NUM> of the clip arms <NUM> defined by the bend of the one-piece element <NUM> at the midpoint <NUM>. In other words, the pin <NUM> extends immediately distal of the midpoint <NUM> so that the pin <NUM> extends between the pair of arms <NUM> along an interior surface of the one-piece element <NUM> along the bend at the midpoint <NUM>. The tension member <NUM> and the pin <NUM> are connected to the one-piece element <NUM> such that longitudinal movement of the tension member <NUM> relative to the capsule <NUM> correspondingly moves the clip arms <NUM> relative to the capsule <NUM>. The proximal end <NUM> of the tension member <NUM> is sized and shaped to engage a correspondingly sized and shaped portion of the yoke <NUM>. In one embodiment, the proximal end <NUM> includes a substantially C-shaped protrusion.

The yoke <NUM> extends from a proximal end <NUM> configured to be connected to a control member such as, for example, a pull wire to a distal end <NUM> configured to releasably engage the proximal end <NUM> of the tension member <NUM>. In one embodiment, the distal end <NUM> included a substantially C-shaped recess <NUM> sized and shaped to receive the C-shaped protrusion of the proximal end <NUM>. The proximal end <NUM> of the tension member <NUM> and the distal end <NUM> of the yoke <NUM> are configured to disengage one another when subject to a predetermined force as will be described in more detail below.

In one embodiment, a width along at least a portion of the yoke <NUM> substantially corresponds to a width (e.g., diameter) of the channel <NUM> of the capsule <NUM> so that, when the yoke <NUM> is positioned within the proximal end <NUM> of the capsule <NUM>, the yoke <NUM> engages the tabs <NUM> to move the tabs <NUM> radially outward, out of engagement with the proximal portion of the device. The yoke <NUM> also includes a pair of overhangs <NUM> extending distally from a portion thereof. As will be described in further detail below, the overhangs <NUM> are configured to constrain proximal ends <NUM> of locking arms <NUM> of the locking mechanism <NUM> so that the locking arms <NUM> are prevented from engaging the locking features <NUM> of the capsule <NUM> until the clip <NUM> has been deployed over target tissue.

The locking mechanism <NUM> is attached to the tension member <NUM> and, as described above, includes locking arms <NUM> that are constrained by the yoke <NUM> until the clip <NUM> is deployed. In one embodiment, the locking mechanism <NUM> includes a ring <NUM> and a pair of locking arms <NUM> extending proximally from the ring <NUM>. The ring <NUM> is attached to the tension member <NUM> via the same pin <NUM> that connects the tension member <NUM> to the clip arms <NUM>. In particular, the pin <NUM> extends diametrically across the ring <NUM> so that the ring <NUM> extends about both the distal end <NUM> of the tension member <NUM> and the proximal end <NUM> of the clip arms <NUM>.

The locking arms <NUM> extend proximally from the opposing sides of the ring <NUM> to the proximal ends <NUM> and, in one embodiment, are biased radially outward. The ring <NUM> is connected to the tension member <NUM> so that the locking arms <NUM> extend along opposing sides of the tension member <NUM> to be constrained via the overhangs <NUM> of the yoke <NUM>. The proximal ends <NUM> of the locking arms <NUM> include locking structures <NUM> extending therefrom so that, when the proximal ends <NUM> are permitted to revert to their biased configuration, the locking structures <NUM> engage the locking features <NUM> of the capsule <NUM>. In one embodiment, the locking structures <NUM> are configured as locking tabs extending from the proximal ends <NUM> to engage locking windows <NUM> of the capsule <NUM> when the proximal ends <NUM> are released from the overhangs <NUM>. As will be described in further detail below, the proximal ends <NUM> are released and permitted to revert to their radially outwardly biased configuration when the predetermined force is exerted on the yoke <NUM> to separate the yoke <NUM> from the tension member <NUM>.

According to an exemplary method, the clip <NUM> of the clip device <NUM> is inserted to a target site within the body via, for example, a working channel of an endoscope. The clip <NUM> is inserted through the working channel in the closed configuration so that the clip arms <NUM> do not damage in interior of the working channel. Once the clip <NUM> has reached the target site, the clip arms <NUM> are moved distally relative to the capsule <NUM> extending distal portions of the clip arms <NUM> out of the capsule <NUM> and freeing the clip arms <NUM> to move apart 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 repeatedly moved between the open and closed configurations until a target portion of tissue is positioned between the clip arms <NUM> as desired. The user then draws the clip arms <NUM> proximally into capsule <NUM> so that, as the clip arms <NUM> are drawn into the capsule <NUM>, the clip arms <NUM> are drawn toward one another to grip the target tissue between the distal ends <NUM> of the clip arms <NUM>. As described above, the clip <NUM> may be moved between the open and closed configurations via movement of, for example, the control member <NUM> coupled to the yoke <NUM>.

When the user is satisfied that the clip <NUM> is in a desired position gripping the target tissue, the user applies increasing proximally directed force to the control member <NUM> after the engaging features <NUM> have engaged the capsule <NUM>, as described above, until the predetermined force is pulling the yoke <NUM> proximally away from the tension member <NUM> so that they disengage from one another. As the yoke <NUM> is separated from the tension member <NUM>, the proximal ends <NUM> of the locking mechanism <NUM> of the clip arms <NUM> are released from the overhangs <NUM> of the yoke <NUM>, freeing the proximal ends <NUM> to spring toward their radially outwardly biased configuration until the locking tabs <NUM> engage the locking windows <NUM> of the capsule <NUM>, thereby locking the clip <NUM> in the closed configuration.

The yoke <NUM> may then be drawn further proximally relative to the capsule <NUM> (e.g., via the control member connected thereto) until a portion of the yoke <NUM> having a width corresponding to the channel <NUM> of the capsule <NUM> is positioned within the proximal end <NUM> of the capsule <NUM>, urging the radially inwardly crimped tabs <NUM> radially outward, out of engagement with, for example, the bushing <NUM> of the proximal portion <NUM> of the device <NUM> and separating the clip <NUM> from the proximal portion <NUM>. Thus, the clip <NUM> remains clipped over the target tissue while the proximal portion <NUM> may be removed from the body. In one embodiment, upon separation of the clip <NUM><NUM> I from the proximal portion <NUM>, the tabs <NUM> revert to their radially inwardly crimped configuration so that the yoke <NUM>, although separated from the tension member <NUM>, remains attached to the proximal end <NUM> of the capsule <NUM>.

In this embodiment, a further proximal force exerted on the control member <NUM> separates the control member from the yoke <NUM>, leaving the clip <NUM> in the body and allowing the proximal portion <NUM> of the device <NUM>, including the control member <NUM>, to be removed therefrom. According to another embodiment, upon separation of the capsule <NUM> from the proximal portion <NUM>, the yoke <NUM> may be drawn proximally out of the capsule <NUM> so that the clip <NUM> remains within the body, clipped over the target tissue, while the proximal portion <NUM> and the yoke <NUM> may be removed from the body.

Claim 1:
A device for treating tissue, comprising:
a capsule (<NUM>) extending longitudinally from a proximal end (<NUM>) to a distal end (<NUM>) and including a channel (<NUM>) extending therethrough;
a one-piece clipping element (<NUM>) defining a pair of clip arms (<NUM>), proximal ends (<NUM>) of which are received within the channel (<NUM>) so that the first and second clip arms (<NUM>) are movable relative to one another between an open configuration and a closed configuration;
a deployment mechanism (<NUM>) including a tension member (<NUM>) connected to a proximal end (<NUM>) of the first and second clip arms (<NUM>), a yoke (<NUM>) releasably coupled to the tension member (<NUM>) and longitudinally movable relative to the capsule (<NUM>) to move the first and second clip arms (<NUM>) between the open and closed configurations, the tension member (<NUM>) and yoke (<NUM>) configured to separate from one another to release the device from a proximal portion thereof, in response to a predetermined proximal force relative to the tension member (<NUM>);
a locking mechanism (<NUM>) coupled to the one-piece clipping element (<NUM>) and to the deployment mechanism (<NUM>) and including a pair of locking fingers (<NUM>) configured to engage a corresponding locking feature (<NUM>) of the capsule (<NUM>) to lock the first and second clip arms (<NUM>) in the closed configuration, when the yoke (<NUM>) is separated from the tension member (<NUM>); and
characterized in that the locking mechanism (<NUM>) is separate from the one-piece clipping element (<NUM>).