Patent Description:
Physicians have become more willing to perform aggressive interventional and therapeutic endoscopic gastrointestinal (GI) procedures, which may increase the risk of perforating the wall of the GI tract or may require closure of the GI tract wall as part of the procedure. Such procedures may include, for example, the removal of large lesions, tunneling under the mucosal layer of the GI tract to treat issues below the mucosa, full thickness removal of tissue, treatment of issues on other organs by passing outside of the GI tract, and endoscopic treatment/repair of post-surgical issues (e.g., post-surgical leaks, breakdown of surgical staple lines, and anastomotic leaks). Currently, tissue may be treated via endoscope closure devices such as, for example, hemostasis clips inserted through an endoscope. Depending on the size of the defect, multiple clips may be required. In some cases, however, current endoscopic closure devices may be difficult to use, time consuming to position, or insufficient for certain perforations, conditions and anatomies.

<CIT> relates to a system for treating tissue which includes a clip assembly including a pair of clip arms, proximal ends of which are slidably received within a channel of a capsule to be moved between a tissue receiving configuration, in which distal ends of the clip arms are separated from one another, and a tissue clipping configuration, in which the distal ends are moved toward one another. The system also includes an applicator including a catheter and a control member extending therethrough. The control member is configured to be connected to the clip arms to move the clip assembly between the tissue receiving and tissue clipping configurations. The system also includes a coupler attached to one of a proximal end of the capsule of the clip assembly and a distal end of the catheter which is configured to releasably couple the capsule and the catheter to one another.

The present disclosure relates to a clipping system for treating tissue. The system includes an insertion device extending longitudinally from a proximal end to a distal end and including a channel extending therethrough, the insertion device including a plurality of longitudinal slots extending through a wall thereof and along a distal portion thereof such that the longitudinal slots are open to the channel and the distal end of the insertion device. The system also includes a clip releasably received within the distal portion of the insertion device, the clip including a capsule extending longitudinally from a proximal end to a distal end and including a channel extending therethrough, and a pair of clip arms, proximal ends of which are slidably received within the channel of the capsule to move the clip arms between an open configuration, in which distal ends thereof are separated from one another to receive a tissue therebetween, and a closed configuration, in which the distal ends are drawn toward one another to grip tissue therebetween.

The system further includes a collet slidably mounted over the insertion device and movable between an insertion configuration, in which the collet is positioned over the distal portion of the insertion device to press the distal portion against the capsule and to hold the capsule therein, and a deployed configuration, in which the collet is proximal the distal portion so that the clip is releasably from the distal portion of the insertion device. Furthermore, the system includes a control member extending through the channel of the insertion device to be coupled to the proximal ends of the clip arms and a portion of the collet so that movement of the clip between the open and closed configurations and movement of the collet between the insertion configuration and the deployed configuration is controlled via a longitudinal movement of the control member relative to the insertion device.

In an embodiment, the system further includes a yoke coupling the control member to the clip arms and the collet, the yoke including a distal portion connected to the clip arms and a proximal portion connected to a portion of the collet, the distal and proximal portions of the yoke connected to one another via a separable connection that is configured to separate when subject to a predetermined force exceeding a predetermined threshold value.

In an embodiment, the distal portion is received between the proximal ends of the clip arms and include protrusions extending from opposing sides thereof, the protrusions received within openings extending through a proximal portion of the clip arms.

In an embodiment, the proximal portion houses a distal end of the control member therein and includes a longitudinal groove extending therealong, an engaging tab of the collet extending into the channel of the insertion to be slidably received within the longitudinal groove.

In an embodiment, a length of the longitudinal groove corresponds to a distance via which the control member is moved relative to the insertion device during a movement of the clip between the open and the closed configurations.

In an embodiment, the proximal ends of the clip arms are biased radially outward and include locking structures extending laterally therefrom so that, when the proximal ends of the clip arms are moved proximally of the proximal end of the capsule, the locking structures engage a proximal edge of the capsule to lock the clip in the closed configuration.

In an embodiment, the clip arms include engaging features configured to engage portion of the capsule such that, when the engaging features engage the capsule, the clip arms are prevented from moving further proximally relative to capsule and the predetermined force is exerted on the distal end of the control member.

In an embodiment, the distal ends of the clip arms are biased toward the open configuration so that, when the clip arms are drawn into the capsule, the clip arms are constrained toward the closed configuration via an interior surface of the capsule and, when the clip arms are moved distally out of the capsule, the clip arms are permitted to revert to their biased open configuration.

In an embodiment, the capsule is keyed to the insertion device so that a rotation of the insertion device correspondingly rotates the clip.

In an embodiment, the insertion device is keyed to the collet so that a rotation of the insertion device correspondingly rotates the collet and the clip.

In an embodiment, the insertion device further includes a crimp tab positioned immediately distal a proximal end of the collet when the collet is in the insertion configuration and extending into the channel of the insertion device, the crimp tab deformable to permit the collet to move proximally therepast when subject to a predetermined force exceeding a predetermined threshold value via the collet.

The present disclosure also relates to a clipping system which includes a catheter extending longitudinally from a proximal end to a distal end and including a channel extending therethrough, the catheter including a plurality of longitudinal slots extending through a wall thereof from the distal end along a distal portion of the catheter; a clip including a capsule extending longitudinally from a proximal end to a distal end and including a channel extending therethrough, and a pair of clip arms, proximal ends of which are slidably received within the channel of the capsule to move the clip arms between an open configuration and a closed configuration, the capsule of the clip configured to be releasably received within the distal portion of the catheter; a collet slidably mounted over the catheter and movable between an insertion configuration, in which the collet is positioned over the distal portion of the catheter to press the distal portion against the capsule and to hold the capsule therein, and a deployed configuration, in which the collet is proximal the distal portion so that the clip is releasably from the distal portion of the catheter; and a control member connected to the clip arms and the collet via a yoke, the yoke including a distal portion connected to the clip arms and a proximal portion connected to a portion of the collet, the distal and proximal portions of the yoke connected to one another via a separable connection that is configured to separate when subject to a predetermined force exceeding a predetermined threshold value.

In an embodiment, the proximal portion houses an enlarged distal end of the control member therein and includes a longitudinal groove extending therealong, an engaging tab of the collet extending into the channel of the insertion to be slidably received within the longitudinal groove.

In addition, the present disclosure relates to a method for treating target tissue. The method includes inserting a clip through a working channel of an endoscope to a target site within a body via a catheter, the clip inserted through the endoscope in an insertion configuration in which the clip is received within a distal portion of the catheter and held therein via a collet mounted thereover, the clip including a capsule and a pair of clip arms slidably received therein; moving the clip between an open configuration and a closed configuration via a control member coupled to the clip arms until selected target tissue is received between distal ends of the clip arms, the clip arms coupled to the control member via a yoke; drawing the clip arms further proximally into the capsule until locking tabs at proximal ends of the clip arms engage a portion of the capsule to lock the clip arms in the closed configuration; and deploying the clip from the catheter by drawing the collet proximally relative to the catheter via the control member until the collet is proximal the distal portion and the clip is releasably therefrom, a portion of the collet slidably coupled to the yoke.

In an embodiment, the deploying the clip includes drawing the control member proximally relative to the catheter until the yoke connecting the control member to the clip is subject to a predetermined force exceeding a predetermined threshold value so that a proximal portion of the yoke connected to a distal end of the control member is separated from a distal portion of the yoke connected to the clip arms.

In an embodiment, the moving the clip between the open configuration and the closed configuration causes an engaging portion of the collet to be slid within a longitudinal groove extending along the proximal portion of the yoke.

In an embodiment, the proximal and distal portions of the yoke are separated from one another when engaging features of the clip arms engage a portion of the capsule to prevent the clip arms from moving further proximally relative to capsule while the control member is moved further proximally relative to the catheter.

In an embodiment, the deploying the clip includes drawing the control member proximally relative to the catheter so that the collet is pressed proximally against a crimp tab of the catheter until tab to permit the collet to be moved proximally therepast.

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 system for treating, for example, internal tissue perforations, defects and/or bleeds. Exemplary embodiments of the present disclosure describe a clipping system comprising a clip releasably coupled to a catheter via a collet that is slidable relative to the catheter to deploy the clip. The collet coupling minimizes the possibility of the clip being inadvertently reengaged with the catheter during or after deployment, while also allowing for a deployed clip that is shortened compared to most current clips which include a joint at a proximal end of the clip that couples the clip to the catheter. A shorter deployed clip may improve visualization of a target site and allow better maneuverability when placing multiple clips.

A yoke of the deployment mechanism according to the exemplary embodiment includes a proximal portion configured to break and/or separate from a distal portion of the yoke so that the proximal portion, which is connected to both the distal end of a control member and a proximal end of the collet, is entirely separated and removed from the deployed clip during deployment and then removed from the body, to eliminate any shed parts. Some current clip designs create shed parts during the process of separating the clip from the catheter which shed parts are left in the body after the procedure has been completed. As larger defect cases such as Peroral Endoscopic Myotomy (POEM) and Endoscopic Submucosal Dissection (ESD) become more prevalent, physicians may prefer clips that do not generate shed parts that may become embedded in tissue defects. 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 system.

<FIG> show a clipping system <NUM> for treating tissue defects. The clipping system <NUM> comprises a clip <NUM> releasably coupled to a catheter <NUM> via a collet <NUM> slidably mounted over the catheter <NUM> to move the clipping system <NUM> between an insertion configuration, as shown in <FIG>, and a deployed configuration, as shown in <FIG>. The clip <NUM> includes a pair of clip arms <NUM>, proximal ends <NUM> of which are slidably received within a capsule <NUM> so that the clip <NUM> may be moved 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. In an insertion configuration, the capsule <NUM> is received within a distal portion <NUM> of the catheter <NUM>, the collet <NUM> positioned over the distal portion <NUM> to hold the capsule <NUM> therein.

Upon insertion of the clip <NUM> to a target site in a body, the clip <NUM> may be moved between the open and closed configuration via a control member <NUM> that extends from a distal end <NUM> coupled to the clip arms <NUM> to a proximal end extending proximally of a proximal end of the catheter <NUM> at which it is accessible to a user of the system <NUM> (e.g., surgeon). The control member <NUM> is connected to the clip arms <NUM> via a yoke <NUM> including a distal portion <NUM> connected to the clip arms <NUM> and a proximal portion <NUM> fixedly connected to the distal end <NUM> of the control member <NUM> and slidably connected to the collet <NUM>. The distal and proximal portions <NUM>, <NUM> of the yoke <NUM> are configured to break apart or otherwise separate from one another.

Thus, when tissue has been gripped via the clip arms <NUM>, as desired, the clip <NUM> is deployed by drawing the control member <NUM> proximally relative to the catheter <NUM> until the clip arms <NUM> are locked with respect to the capsule <NUM>, the proximal portion <NUM> of the yoke <NUM> is separated from the distal portion <NUM> of the yoke <NUM> and the collet <NUM> is drawn proximally relative to the catheter <NUM> so that the capsule <NUM> and the clip <NUM> are released from the proximal portion of the device which may then be withdrawn from the body while leaving the clip <NUM> in position within the body clipped to the target tissue.

As shown in <FIG>, the clip <NUM> includes the clip arms <NUM> and the capsule <NUM>. The capsule <NUM> extends longitudinally from a proximal end <NUM> to a distal end <NUM> and includes a channel <NUM> extending therethrough. The distal end <NUM> of the capsule <NUM> in this embodiment includes a pair of capsule tabs <NUM> extending therefrom and bent radially inward into the channel <NUM>. In one embodiment, the capsule tabs <NUM> are diametrically opposed from one another so that the capsule tabs <NUM> aid in alignment and positioning of the clip arms <NUM>, as will be described in further detail below.

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 channel <NUM>. Specifically, the proximal end <NUM> of each of the clip arms <NUM> is slidably received within the channel <NUM> allowing the clip <NUM> to be moved between the open and closed configurations via manipulation of the control member <NUM>. In one embodiment, the clip arms <NUM> are diametrically opposed to one another within the channel <NUM>, extending along opposite sides of the capsule tabs <NUM>.

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 form one another toward the open configuration under their natural bias. When the clip arms <NUM> are drawn proximally into the capsule <NUM>, the clip arms <NUM> are constrained by a wall of the capsule <NUM> and drawn together toward the closed configuration in which the distal ends <NUM> are 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.

The clip arms <NUM> of this embodiment also include engaging features <NUM> extending therefrom. The engaging features are 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 moving further proximally relative to the capsule. In one embodiment, the engaging features <NUM> extend laterally outward from a distal portion <NUM> of each of the clip arms <NUM> so that the distal portion <NUM> has a width greater than that of a proximal portion <NUM> of the clip arm <NUM> which is sized and shaped to permit the proximal portion <NUM> to be drawn proximally into the capsule <NUM>.

Thus, as the clip arms <NUM> are drawn proximally into the capsule <NUM>, the engaging features <NUM> abut the capsule tabs <NUM> and/or a distal face <NUM> of the capsule <NUM>, preventing the distal portions <NUM> of the clip arms <NUM> from being drawn proximally into the capsule <NUM>. The engaging features <NUM> are positioned along 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.

At least one of the proximal ends <NUM> of the clip arms <NUM> (in this embodiment, the proximal ends <NUM> of both of the clip arms <NUM> include a locking feature) includes a locking feature such as, for example, a locking tab <NUM> extending therefrom positioned and shaped to engage a corresponding locking portion of the capsule <NUM> when the clip <NUM> has been drawn proximally into the capsule <NUM> to a locking position. The proximal ends <NUM> of the clip arms <NUM>, in this embodiment, are biased radially outward, away from a centerline of the capsule <NUM>. Before the clip <NUM> is locked, the proximal ends <NUM> are restrained via an interior surface <NUM> of the capsule <NUM> so that the proximal ends <NUM> are slidable along the interior surface <NUM> of the channel <NUM> as the clip <NUM> is moved between the open and the closed configurations.

When the target tissue has been gripped via the clip arms <NUM> and it is desired to lock the clip arms <NUM> in the closed configuration, the clip arms <NUM> are drawn further proximally relative to the capsule <NUM> until the proximal ends <NUM> move proximally past the proximal end <NUM> of the capsule <NUM> so that the proximal ends <NUM> are no longer constrained via the capsule <NUM> and are freed to move radially away from one another under their natural bias. The locking tabs <NUM> thereby spring radially outward to engage a proximal edge <NUM> of the capsule <NUM> so that the clip arms <NUM> are prevented from moving distally relative to the capsule <NUM> and the clip arms <NUM> are held in the closed configuration. In this embodiment, a distance between the engaging features <NUM> and the locking tabs <NUM> of the clip arms <NUM> substantially corresponds to a length of the capsule <NUM>.

In the locked configuration, the engaging features <NUM> engage the distal end of the capsule <NUM> while the locking tabs <NUM> extend proximally of the capsule <NUM>, thereby locking the clip arms <NUM> relative to the capsule <NUM> in the closed configuration. In an exemplary embodiment, the proximal portion <NUM> of each of the clip arms <NUM> also includes an opening <NUM> extending therethrough. As will be described in further detail below, the opening <NUM> receives a portion of the yoke <NUM> therein so that the clip arms <NUM> are held in a desired alignment relative to one another and so that the clip arms <NUM> may be connected to the control member <NUM>.

According to one example, the clip <NUM> has a rigid length of approximately <NUM> inches. As will be understood be understood by those of skill in the art, the clip <NUM> may have a shortened length relative to other standard hemostatic clips. In particular, since the clip <NUM> does not require a separate coupling joint for connecting the capsule <NUM> to the catheter <NUM> and because the clip arms <NUM> engage the proximal edge <NUM> of the capsule <NUM> rather than a locking structure along a length of the capsule <NUM>, the capsule <NUM> may be reduced in length compared to conventional hemostatic clipping devices. In one example, the capsule <NUM> may be reduced in length by approximately <NUM> inches. It will be understood by those of skill in the art, however, that the clip <NUM> and capsule <NUM> may have any of a variety of lengths so long as the clip arms <NUM> are coupled to the control member <NUM> and the capsule <NUM> is configured to be received within the distal portion <NUM> of the catheter <NUM>, as described in further detail below.

As described above, the clip arms <NUM> are connected to the control member <NUM> via the yoke <NUM>. As shown in <FIG>, <FIG> and the yoke <NUM> includes the distal portion <NUM> and the proximal portion <NUM> connected to one another via a separable connection <NUM> which is configured to break, fail or otherwise separate when subjected to a predetermined force exceeding a threshold force. In one embodiment, the distal and proximal portions <NUM>, <NUM> are connected to one another via a frangible link including, for example, a reduced diameter portion configured to break when the yoke <NUM> is subject to the predetermined force. In another embodiment, the distal and proximal portions <NUM>, <NUM> are connected to one another via corresponding mating features which deform and release from one another when subject to the predetermined force. It will be understood by those of skill in the art, however, that the distal and proximal portions <NUM>, <NUM> may be connected to one another via any of a number of connections so long as the distal and proximal portions <NUM>, <NUM> are configured to separate from one another when subject to the predetermined force.

The distal portion <NUM> of the yoke <NUM> is received between the proximal ends <NUM> of the clip arms <NUM>. The distal portion <NUM> of the yoke <NUM> includes a pair of protrusions <NUM> extending from opposing surfaces thereof so that each protrusion <NUM> is received within a corresponding one of the openings <NUM> of the clip arms <NUM> to maintain a desired alignment between the clip arms <NUM>. Thus, each protrusion <NUM> is sized and shaped to correspond to a shape of the corresponding one of the openings <NUM>.

The proximal portion <NUM> of the yoke <NUM> extends longitudinally and houses the distal end <NUM> of the control member <NUM> therein. In one embodiment, the control member <NUM> includes an enlarged distal end <NUM> received within a correspondingly sized and shaped recess <NUM> within the proximal portion <NUM> of the yoke <NUM>. It will be understood by those of skill in the art, however, that the proximal portion <NUM> may be connected to the distal end <NUM> of the control member <NUM> in any of a number of ways so long as moving the control member <NUM> longitudinally relative to the catheter <NUM> and capsule <NUM> correspondingly moves the clip arms <NUM> to which the yoke <NUM> is connected and so that, upon separation of the proximal portion <NUM> of the yoke <NUM> from the distal portion <NUM>, the control member <NUM> remains connected to the proximal portion <NUM>.

According to an embodiment, the proximal portion <NUM> also includes a longitudinal groove <NUM> extending longitudinally along an exterior surface <NUM> of the proximal portion <NUM>. The longitudinal groove <NUM> is configured to slidably receive a portion of the collet <NUM>, as will be described in further detail below. In another embodiment, the proximal portion <NUM> includes a pair of longitudinal grooves <NUM> extending along opposing sides of the proximal portion <NUM>. In yet another embodiment, the longitudinal grooves <NUM> extend laterally through the proximal portion <NUM> of the yoke <NUM> so that the longitudinal groove <NUM> receives portions of the collet <NUM> therein, from opposing sides of the yoke <NUM>.

The clip <NUM>, as described above, is releasably coupled to a catheter <NUM>, as shown in <FIG> (or to any other flexible insertion device) sized and configured for insertion through, for example, a working channel of an endoscope, to a target site within a body. The catheter <NUM> or other insertion device is, in one embodiment, sufficiently flexible to navigate through even tortuous paths of a body lumen as would be understood by those skilled in the art. The catheter <NUM> extends longitudinally from a distal end <NUM> to a proximal end which, when the clipping system <NUM> is in use and the clip <NUM> has been inserted to the target site, remains outside the body. The catheter <NUM> includes a channel <NUM> extending longitudinally therethrough.

The channel <NUM> is sized and shaped to receive the capsule <NUM> therein and a distal portion <NUM> of the catheter <NUM> includes a plurality of longitudinal slots <NUM> extending through a wall <NUM> thereof. The longitudinal slots <NUM> are open to the distal face <NUM> of the capsule <NUM> and in communication with the channel <NUM> so that the clip <NUM> may be received within the distal portion <NUM>. The clip <NUM> is received substantially coaxially within the channel <NUM> so that a portion of the yoke <NUM> is received within the channel <NUM> and the control member <NUM> extends from the yoke <NUM>, through the channel <NUM>, to the proximal end which is accessible via a user of the system <NUM> (e.g., via any known actuator (not shown)). The distal end <NUM> of the catheter <NUM> includes a lip <NUM> extending about a perimeter thereof. The lip <NUM> acts as a stop which, as will be described in greater detail below, prevents the collet <NUM> from being moved distally therebeyond.

In one embodiment, the catheter <NUM> includes two longitudinal slots <NUM> extending along the distal portion <NUM>. The longitudinal slots <NUM> of this embodiment extend through the wall <NUM> along opposing sides of the catheter <NUM>. In another embodiment, the catheter <NUM> includes three longitudinal slots <NUM> extending along the distal portion <NUM>. The longitudinal slots <NUM> are, in certain embodiments, equally circumferentially spaced from one another about a perimeter of the catheter <NUM>. It will be understood by those of skill in the art that although the exemplary embodiments specifically show a catheter <NUM> including two or three longitudinal slots <NUM>, the catheter <NUM> may include any number of longitudinal slots <NUM>. It will also be understood by those of skill in the art that although the exemplary embodiments show and describe the longitudinal slots <NUM> equally spaced relative to one another, the catheter <NUM> may have any number of longitudinal slots <NUM> in any of a variety of configurations so long as the longitudinal slots <NUM> facilitate slidable insertion of the capsule <NUM> within the distal portion <NUM>.

Proximally of the longitudinal slots <NUM>, the catheter <NUM> includes an engaging slot <NUM> extending through the wall <NUM> along a portion of a length thereof. The engaging slot <NUM> is receives a portion of the collet <NUM> from an exterior of the capsule <NUM> into the channel <NUM> so that the collet <NUM> is slidably engaged with the longitudinal groove <NUM> of the proximal portion <NUM> of the yoke <NUM>. In one embodiment, the catheter <NUM> includes one engaging slot <NUM>. In another embodiment, the catheter <NUM> includes two engaging slots <NUM> with the engaging slots <NUM> extending through opposing portions of the catheter <NUM> and corresponding to the size and position of the longitudinal grooves <NUM> of the proximal portion <NUM> of the yoke <NUM>.

The collet <NUM> is slidably mounted over the distal portion <NUM> of the catheter <NUM> for movement between the insertion configuration and the deployed configuration. In the insertion configuration, as shown in <FIG>, the collet <NUM> is positioned over the distal portion <NUM> of the catheter <NUM> so that the distal portion <NUM> is pressed against the capsule <NUM>, holding the capsule <NUM>, and thereby the clip <NUM>, therein. It will be understood by those of skill in the art that the collet <NUM> may be mounted over the distal portion <NUM> and held in position thereover via a friction fit. In the insertion configuration, the collet <NUM> of this embodiment abuts the lip <NUM> at the distal end <NUM> of the catheter <NUM> so that the collet <NUM> is prevented from moving distally past the distal end <NUM> of the catheter <NUM> and thus does not interfere with the opening and closing of the clip arms <NUM>. When moving toward the deployed configuration, as shown in <FIG>, the collet <NUM> is moved proximally along the catheter <NUM> until the collet <NUM> is proximal of the longitudinal slots <NUM> thereof. In the deployed configuration, the distal portion <NUM> of the catheter <NUM> is no longer pressed against the capsule <NUM> freeing the clip <NUM> to be released from therefrom.

As will be understood by those of skill in the art, as the collet <NUM> is moved over the distal portion <NUM> toward the insertion configuration, a width of the longitudinal slots <NUM> (i.e., a distance between longitudinal sides of the longitudinal slots <NUM>) is reduced so that the inner diameter of the distal portion <NUM> is reduced and the catheter <NUM> is held firmly against the capsule <NUM> retaining the capsule <NUM> and the clip <NUM> within the catheter <NUM>. As the collet <NUM> is moved toward the deployed configuration, the with of the longitudinal slots <NUM> is permitted to widen so that the distal portion <NUM> is no longer pressed firmly against the capsule <NUM>. Thus, the clip <NUM> may be released from the catheter <NUM> by drawing the catheter <NUM> proximally away from the clip <NUM>.

The collet <NUM> of this embodiment includes a ring portion <NUM> sized and shaped to extend about the catheter <NUM> and a pair of fingers <NUM> extending proximally therefrom to extend longitudinally along portion of the catheter <NUM>. At a proximal end <NUM> of each of the fingers <NUM>, the collet <NUM> includes an engaging tab <NUM> extending radially inward. Each of the engaging tab <NUM> is configured to be extend through a corresponding one of the engaging slots <NUM> to be received within a corresponding one of the longitudinal grooves <NUM> of the proximal portion <NUM>. Each engaging tab <NUM> is longitudinally slidable within the corresponding longitudinal groove <NUM> to permit movement of the clip <NUM> between the open and closed configurations while the clipping system <NUM> is in the insertion configuration.

In particular, while the collet <NUM> remains stationary over the catheter <NUM> and the control member <NUM> is moved distally and proximally relative to the catheter <NUM> to move the clip <NUM> between the open and the closed configuration, respectively, the yoke <NUM> slides along the engaging tab <NUM> via the longitudinal groove <NUM>. Thus, a length of the longitudinal groove <NUM> corresponds to a range over which the control member <NUM> may be moved relative to the catheter <NUM> as the clip <NUM> is moved between the open and the closed configurations.

Once it is determined that the clip <NUM> has been closed over target tissue as desired, the control member <NUM> is drawn proximally relative to the catheter <NUM> until the engaging tabs <NUM> engages a distal end <NUM> of the longitudinal groove <NUM>. At this point, when the control member <NUM> is moved further proximally relative to the catheter <NUM>, the collet <NUM> is also drawn proximally relative to the catheter <NUM> toward the deployed configuration. As the collet <NUM> is moved proximally along the catheter <NUM>, the engaging tab <NUM> of each of the fingers <NUM> slides proximally through the corresponding one of the engaging slots <NUM>. It will be understood by those of skill in the art that although the exemplary embodiments show and describe the collet <NUM> as including two fingers <NUM>, the collet <NUM> may include any number of fingers <NUM> (and so long as the number of fingers <NUM> and engaging tabs <NUM> correspond to then number of longitudinal grooves <NUM> along the proximal portion <NUM> of the yoke <NUM>.

According to another exemplary embodiment, as shown in <FIG>, a system <NUM> is substantially similar to the system <NUM> including all of the features the system as described above except for the differences discussed below. A capsule <NUM>, catheter <NUM> and collet <NUM> of the system <NUM> are in this embodiment substantially similar to system <NUM> described above. The capsule <NUM> and the catheter <NUM>, however, may be correspondingly sized and shaped so that, when a portion of the capsule <NUM> is received within longitudinal slots <NUM>, torque may be transferred from the catheter <NUM> to the clip <NUM> so that rotation of the catheter <NUM> to the clip <NUM>. In one example, the capsule <NUM>, catheter <NUM> and the collet <NUM> have a substantially oval cross-sectional shape. In another example, the capsule <NUM> includes features <NUM> keyed to the longitudinal slots <NUM> so that the capsule <NUM> is prevented from being rotated relative to the catheter <NUM>. Thus, a torsional force applied to the catheter <NUM> (e.g., via rotation of the catheter <NUM>) is transferred to the clip <NUM>.

In another exemplary embodiment, as shown in <FIG>, a ring portion <NUM> of a collet <NUM> according to a system <NUM> includes key features <NUM> received within the longitudinal slots <NUM> of a catheter <NUM> so that, a rotation of the catheter <NUM> correspondingly rotates the collet <NUM> and a capsule <NUM>. In one embodiment, the key feature <NUM> is configured as a protrusion extending radially inward from an interior surface of the ring portion <NUM> along a length thereof. It will be understood by those of skill in the art, however, that the embodiments shown in <FIG> are exemplary only and that there are any number of ways for the catheter <NUM> to be keyed to the clip <NUM> and/or collet <NUM> so that a rotation of the catheter <NUM> provides a torque transfer to the clip <NUM>.

According to an exemplary method utilizing the system <NUM>, the clip <NUM> is inserted through, for example, a working channel of an endoscope to a target site within a body. In the insertion configuration, the clip <NUM> remains coupled to the catheter <NUM> via the collet <NUM>. The clip <NUM> is inserted into the body via the catheter <NUM>, in the closed configuration, so that a proximal end of the catheter <NUM> remains exterior to the body. Once the clip <NUM> has reached the target site, the user advances the control member <NUM> distally to advance the clip arms <NUM> distally out of the capsule <NUM>, freeing the clip arms <NUM> to move under their natural bias toward the open configuration so that target tissue may be received between the clip arms <NUM>.

The user may then operate the control member <NUM> to move the clip <NUM> between the open and closed configurations, as desired, until a target portion of tissue is positioned between the clip arms <NUM> as desired. The user then draws the control member <NUM> proximally (or advances the catheter <NUM> distally over the control member <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, while the clip <NUM> is being moved between the open and closed configurations, the engaging tabs <NUM> of the collet <NUM> slide within the longitudinal grooves <NUM> along the proximal portion <NUM> of the yoke <NUM>.

When the user is satisfied that the clip <NUM> is in a desired position gripping the target tissue, the user draws the control member <NUM> proximally relative to the catheter <NUM> until the locking tabs <NUM> at the proximal ends <NUM> of the clip arms <NUM> are moved proximally of the proximal end <NUM> of the capsule <NUM>. Once the proximal ends <NUM> are no longer restrained via the interior surface <NUM> of the capsule <NUM>, the proximal ends <NUM> spring outward away from the centerline of the capsule <NUM> so that the locking tabs <NUM> engage the proximal edge <NUM> of the capsule <NUM> locking the clip arms <NUM> closed over the target tissue. The user continues to draw the control member <NUM> proximally until the engaging features <NUM> engage the capsule tabs <NUM> and/or the distal face <NUM> of the capsule <NUM> and a predetermined force is exerted on the separable connection <NUM> of the yoke <NUM>. When this predetermined force is met or exceeded, the separable connection <NUM> breaks or otherwise releases so that the proximal portion <NUM> of the yoke <NUM> is separated from the distal portion <NUM> of the yoke <NUM>. Thus, the distal portion <NUM> remains within the capsule <NUM>, and the clip <NUM> is locked in the closed configuration while the proximal portion <NUM> is draw proximally away from the clip <NUM>.

The user then operates the actuator to move the control member <NUM> proximally relative to the catheter <NUM> so that the proximal portion <NUM> of the yoke <NUM> is correspondingly moved proximally relative to the catheter <NUM> until the distal end <NUM> of the longitudinal groove <NUM> engages the engaging tabs <NUM> of collet <NUM>. At this point, continued proximal movement of the control member <NUM> draws the collet <NUM> proximally relative to the catheter <NUM>, moving the collet <NUM> from the insertion configuration toward the deployed configuration. As the collet <NUM> is moved toward the deployed configuration, as shown in <FIG>, the engaging tabs <NUM> of the collet <NUM> side along the engaging slots <NUM> of the catheter <NUM>.

When the collet <NUM> reaches the deployed configuration, the distal portion <NUM> of the catheter <NUM> expands and the capsule <NUM> is no longer held frictionally within the distal portion <NUM> of the catheter <NUM>. Thus, drawing the catheter <NUM> proximally relative to the clip <NUM> moves the catheter <NUM> proximally away from the clip <NUM> as shown in <FIG>. Thus, the clip <NUM> may remain in position clipped to the target tissue as the catheter <NUM> is withdrawn from the body. In a further embodiment, upon release of the clip <NUM> from the catheter <NUM> and removal of the catheter <NUM> from the body, the catheter <NUM> may be reloaded with a new clip <NUM> so that additional clips <NUM> may be placed within the body to treat the target site.

According to a further exemplary embodiment, as shown in <FIG>, a system <NUM> is substantially similar to the system <NUM> described above excepted as noted below. The catheter <NUM> further includes a crimp tab <NUM> crimped through a wall of a catheter <NUM> in a position along the catheter <NUM> immediately proximal of a proximal end <NUM> of a collet <NUM>, when the collet <NUM> is in the insertion configuration. The crimp tab <NUM> acts as a stop which prevents the collet <NUM> from being inadvertently moved from the insertion configuration toward the deployed configuration.

Claim 1:
A clipping system (<NUM>, <NUM>) for treating tissue, comprising:
an insertion device (<NUM>, <NUM>) extending longitudinally from a proximal end to a distal end (<NUM>) and including a channel (<NUM>) extending therethrough, the insertion device including a plurality of longitudinal slots (<NUM>) extending through a wall (<NUM>) thereof and along a distal portion (<NUM>) thereof such that the longitudinal slots are open to the channel and the distal end of the insertion device;
a clip (<NUM>) releasably received within the distal portion of the insertion device, the clip including a capsule (<NUM>) extending longitudinally from a proximal end (<NUM>) to a distal end (<NUM>) and including a channel (<NUM>) extending therethrough, and a pair of clip arms (<NUM>), proximal ends (<NUM>) of which are slidably received within the channel of the capsule to move the clip arms between an open configuration, in which distal ends (<NUM>) thereof are separated from one another to receive a tissue therebetween, and a closed configuration, in which the distal ends are drawn toward one another to grip tissue therebetween;
a collet (<NUM>, <NUM>) slidably mounted over the insertion device and movable between an insertion configuration, in which the collet is positioned over the distal portion of the insertion device to press the distal portion against the capsule and to hold the capsule therein, and a deployed configuration, in which the collet is proximal the distal portion so that the clip is releasable from the distal portion of the insertion device; and
a control member (<NUM>, <NUM>) extending through the channel of the insertion device to be coupled to the proximal ends of the clip arms and a portion of the collet so that movement of the clip between the open and closed configurations and movement of the collet between the insertion configuration and the deployed configuration is controlled via a longitudinal movement of the control member relative to the insertion device.