Patent Abstract:
An apparatus for deployment of multiple hemostatic clips, comprises a shaft connected to a handle and a control linkage operatively connected to the handle in combination with a magazine disposed at a distal end of the shaft, the magazine containing a plurality of clips arranged in a chain rotatable within the magazine, wherein a proximal-most one of the clips is coupled to the control linkage, a distal portion of the magazine being contoured to permit opening of a distal-most one of the clips during a distal stroke of the control linkage, and to assist closing and locking of the distal-most clip during a proximal stroke of the control linkage, the magazine including an expanded chamber sized to allow opening in any rotational orientation of a next clip located immediately proximal to the distal-most clip to a degree sufficient to disengage the distal-most clip. A method for deploying multiple hemostatic clips, comprises positioning a distal end of a magazine containing a clip chain over selected target tissue and actuating a control link of the magazine in a distal stroke to open and distally translate a distal-most clip of the clip chain in combination with orienting the open distal-most clip in a desired orientation to grasp the target tissue and actuating the control link in a proximal stroke to close and lock the distal-most clip over the target tissue. The control link is further actuated in the proximal stroke to move a next clip immediately proximal to the distal-most clip into an expanded portion of the magazine sized to allow the next clip to open to a degree sufficient to release the distal-most clip regardless of a circumferential orientation of the next clip.

Full Description:
BACKGROUND 
       [0001]    Endoscopic procedures to treat abnormal pathologies of the gastrointestinal (“GI”) canal, of the biliary tree, of the vascular system and of various other body lumens are becoming increasingly common. An endoscope is basically a hollow tube placed at a desired location within the body to facilitate access to the relevant body ducts and lumens, etc. The endoscope itself cannot carry out many of the required procedures. To that end, the endoscope is fitted with a lumen, or internal channel, which permits the user to insert various medical devices therethrough to the location that requires treatment. Once the distal end of the inserted device has reached the tissue to be treated, it can be manipulated using controls which remain outside the body. 
         [0002]    An hemostatic clipping tool is one of the devices which may be inserted through an endoscope so that treatment may be carried out. Hemostatic clips are deployed from the clipping tool and are used to stop internal bleeding by clamping together the edges of a wound. The clipping tool complete with clips attached to its distal end is inserted through the endoscope to the location of the bleeding. A clip is then remotely manipulated into position over the site of bleeding, clamped over the wound and detached from the tool. After a number of clips sufficient to stop the bleeding has been deployed, the tool is withdrawn from the patient&#39;s body through the endoscope. The size and shape of the clips and of the clipping tool are limited by the inner diameter of the endoscope&#39;s lumen, thus placing constraints on the design of the clip positioning and release mechanisms. 
         [0003]    One challenge facing the endoscope operator is to properly position the hemostatic clips over the wound, so that closing the clips over the tissue will be effective in stopping the bleeding. If a clip is deployed improperly, additional clips may be required to stop the bleeding extending the time required for and the complexity of the procedure and leaving additional medical devices within the patient. It is thus beneficial if the clipping tool allows the user to orient the clips as required during deployment. It is also important for the device operator to be certain of the status of the clip during the deployment operation. For example, before withdrawing the tool from the endoscope, the operator should have positive indication that a clip has fully deployed, and has been released from the tool. At the same time the design of the tool should ensure that clips are fully released after they have been closed over the tissue. 
       SUMMARY OF THE INVENTION 
       [0004]    In one aspect, the present invention is directed to an apparatus for deployment of multiple hemostatic clips, comprising a shaft connected to a handle and a control linkage operatively connected to the handle in combination with a magazine disposed at a distal end of the shaft, the magazine containing a plurality of clips arranged in a chain rotatable within the magazine, wherein a proximal-most one of the clips is coupled to the control linkage. A distal portion of the magazine is contoured to permit opening of a distal-most one of the clips during a distal stroke of the control linkage and to assist closing and locking of the distal-most clip during a proximal stroke of the control linkage. The magazine includes an expanded chamber sized to allow opening in any rotational orientation of a next clip located immediately proximal to the distal-most clip to a degree sufficient to disengage the distal-most clip from the clip chain. 
         [0005]    The present invention is further directed to a method for deploying multiple hemostatic clips, comprising positioning a distal end of a magazine containing a clip chain over selected target tissue and actuating a control link of the magazine in a distal stroke to open and distally translate a distal-most clip of the clip chain in combination with orienting the open distal-most clip in a desired orientation to grasp the target tissue and actuating the control link in a proximal stroke to close and lock the distal-most clip over the target tissue. The control link is further actuated in the proximal stroke to move a next clip immediately proximal to the distal-most clip into an expanded portion of the magazine sized to allow the next clip to open to a degree sufficient to release the distal-most clip from the clip chain regardless of a circumferential orientation of the next clip and the distal-most clip is released by partially opening the next clip. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic side view of a clipping device according to an embodiment of the present invention, with a detail view of an exemplary clip assembly; 
           [0007]      FIG. 2  is a schematic side view of the embodiment shown in  FIG. 1 , with a outer sheath; 
           [0008]      FIG. 3  is a cut away side view of the shaft section according to an embodiment of the present invention; 
           [0009]      FIG. 4  is a cross sectional view of the shaft section shown in  FIG. 3 ; 
           [0010]      FIG. 5  is a detail view of the distal end of the control wire according to an embodiment of the present invention; 
           [0011]      FIG. 6  is a perspective view of an outer sheath according to an embodiment of the present invention; 
           [0012]      FIG. 7  is an cross sectional exploded view of the handle of the outer sheath shown in  FIG. 6 ; 
           [0013]      FIG. 8  is a perspective view of an outer sheath lock according to an embodiment of the present invention; 
           [0014]      FIG. 9  is a cross sectional side view of a distal end of a clipping device according to an embodiment of the present invention; 
           [0015]      FIG. 10  is a cross sectional top view of a distal end of the clipping device shown in  FIG. 9 ; 
           [0016]      FIG. 11  is a perspective view of the distal end of the clipping device shown in  FIG. 9 ; 
           [0017]      FIG. 12  is a top view of the clip arms according to an embodiment of the present invention; 
           [0018]      FIG. 13  is a perspective view of the clip arms shown in  FIG. 12 , according to an embodiment of the present invention; 
           [0019]      FIG. 14  is a perspective view of a capsule according to an embodiment of the present invention; 
           [0020]      FIG. 15  is a cross sectional side view of the of the capsule shown in  FIG. 14 ; 
           [0021]      FIG. 16  is a top view of the distal end of a clipping device according to an embodiment of the present invention; 
           [0022]      FIG. 17  is a side view of the distal end shown in  FIG. 16 ; 
           [0023]      FIG. 18  is a perspective view of a clip arm according to an embodiment of the present invention; 
           [0024]      FIG. 19  is a side view of the clip arm shown in  FIG. 18 ; 
           [0025]      FIG. 20  is a top view of the clip arm shown in  FIG. 18 ; 
           [0026]      FIG. 21  is a perspective view of a bushing according to an embodiment of the present invention; 
           [0027]      FIG. 22  is a cross sectional side view of the bushing shown in  FIG. 21 ; 
           [0028]      FIG. 23  is a perspective view of a wire stop according to an embodiment of the present invention; 
           [0029]      FIG. 24  is a schematic side view of a clip assembly detached from a bushing, according to an embodiment of the present invention; 
           [0030]      FIG. 25  is a side view of a tension member according to an embodiment of the present invention; 
           [0031]      FIG. 26  is a top view of the tension member shown in  FIG. 25 ; 
           [0032]      FIG. 27  is a top view of a yoke according to an embodiment of the present invention; 
           [0033]      FIG. 28  is a perspective view of the yoke shown in  FIG. 27 ; 
           [0034]      FIG. 29  is a top view of a yoke with a control wire according to an embodiment of the present invention; 
           [0035]      FIG. 30  shows a detail of a connection between a control link and a clip chain according to an embodiment of the invention; 
           [0036]      FIG. 31  shows a perspective view of an individual hemostatic clip of a clip chain according to an embodiment of the invention; 
           [0037]      FIG. 32  shows a side elevation view of a clip chain according to an embodiment of the invention; 
           [0038]      FIG. 33  shows a perspective view of a second embodiment of a clip for a clip chain according to the invention; 
           [0039]      FIG. 34  shows a perspective view of a third embodiment of a clip for a clip chain according to the invention; 
           [0040]      FIG. 35  shows a perspective view of the clip chain shown in  FIG. 32 ; 
           [0041]      FIG. 36  shows a perspective view of a clip magazine according to an embodiment of the invention; 
           [0042]      FIG. 37  shows a distal end detail of the clip magazine shown in  FIG. 36 ; 
           [0043]      FIG. 38  shows a cut away perspective view of a clip chain loaded in a clip magazine according to an embodiment of the invention; 
           [0044]      FIG. 39  shows the clip chain of  FIG. 38  being pushed out of the clip magazine; 
           [0045]      FIG. 40  shows the clip chain of  FIG. 38  yet further out of the clip magazine with one clip deployed; 
           [0046]      FIG. 41  shows a distal end detail of the clip magazine shown in  FIG. 39 ; 
           [0047]      FIG. 42  shows the clip chain of  FIG. 38  with a clip deployed and released from the clip chain; 
           [0048]      FIG. 43  is a schematic diagram showing a detail of the magazine an clips according to an embodiment of the present invention; 
           [0049]      FIG. 44  is a cut-away diagram showing two clips in the magazine in a pre-deployment configuration; 
           [0050]      FIG. 45  is a cut-away diagram showing one of the clips shown in  FIG. 44  with open clip arms; 
           [0051]      FIG. 46  is a cut-away diagram showing one of the clips of  FIG. 44  being locked in the closed configuration; 
           [0052]      FIG. 47  is a cut-away diagram showing one of the clips of  FIG. 44  being disconnected from the other clip; and 
           [0053]      FIG. 48  is a cut-away diagram showing one of the clips of  FIG. 44  deployed from the magazine. 
       
    
    
     DETAILED DESCRIPTION 
       [0054]    Hemostatic clips are used routinely to stop bleeding from openings created during surgery as well as wounds resulting from other trauma to tissues. In the simplest form, these clips grasp the tissue surrounding a wound and bring the wound&#39;s edges together, to allow the natural scarring process to heal the wound. Endoscopic hemostatic clips are used to stop internal bleeding due resulting from surgical procedures and/or tissue damage from disease, etc. Specialized endoscopic hemostatic clipping devices are used to bring the clips to the desired location within a patient&#39;s body and to position and deploy the clip at the appropriate place on the tissue. The clipping device is then withdrawn, leaving the clip within the patient. Such hemostatic clipping devices are described in U.S. patent application Ser. No. 10/647.512, filed on Sep. 30, 2003, and Provisional U.S. Patent Application Ser. No. 60/518,167 which are hereby incorporated herein by reference in their entirety. 
         [0055]    Endoscopic hemostatic clipping devices are designed to reach affected tissues deep within a patient&#39;s body, such as within the GI tract, the pulmonary system, the vascular system or within other lumens and ducts. During the procedures to treat those areas, an endoscope is generally used to provide access to and visualization of the tissue which is to be treated. The clipping device may, for example, be introduced through a working lumen of the endoscope. The design and construction of such a “through the scope” endoscopic hemostatic clipping device presents several challenges. The endoscopic clipping device has to be sufficiently small to fit in the lumen of an endoscope and, at the same time, must be designed to provide for the positive placement and actuation of the hemostatic clip. Feedback to the operator is preferably also provided so that the operator will not be confused as to whether the hemostatic clip has been properly locked in place on the tissue and released from the device before the device itself is withdrawn through the endoscope. 
         [0056]      FIG. 1  shows a side elevation view of a through the scope hemostatic clipping device according to an exemplary embodiment of the present invention. This device is a hand operated tool that is used to insert a hemostatic clip through an endoscope lumen, position the clip over a wound, clamp it and deploy it over the affected tissue. The tool is further designed to release the hemostatic clip once it has been clamped in place, and to be withdrawn through the endoscope. To more clearly explain the operation and construction of the exemplary device, it may be divided into three principal components. As shown, the hemostatic clipping device  100  comprises a handle assembly  102 , a shaft section  104 , and a clip assembly  106 . The clip assembly  106  is shown more clearly in the detail A depicted in  FIG. 1 . 
         [0057]    Handle assembly  102  forms the component that supplies a mechanical actuation force to deploy and clamp the clip. In this embodiment, the device is hand operated (i.e., the user&#39;s hands provide the force required to carry out all the functions related to the hemostatic clip). The handle assembly  102  may be constructed in a manner similar to conventional handle assemblies of the type generally employed in endoscopic biopsy devices or in similar applications. The handle assembly  102  allows the user to move a control wire  118  or other force transmission member, which extends through the shaft section  104  to the clip assembly  106  at a distal end of the device  100 . The handle assembly  102  comprises a handle body  108  which can be grasped by the user to stabilize the device and apply a force to it. A sliding spool  110  is connected to control wire  118 , so that the user can easily pull or push said wire  106  as desired. 
         [0058]    As shown in  FIGS. 1 and 2 , a sliding spool  110  is mounted on the handle body  108  so that it can slide along a slot  116 , which maintains its position within the handle assembly  102 . Because the sliding spool  110  is connected to the control wire  118 , the user may manipulate the control wire  118  by grasping the handle body  108  and moving the sliding spool  110  along the slot  116 . A return spring  112  may be provided within the handle body  108  to bias the sliding spool  110 , and thus the control wire  118  toward a desired position. In the present embodiment, the sliding spool  110  is biased to the proximal position. The handle assembly  102  may also include a connection portion  114 , which receives the control wire  118  and attaches the shaft section  104  to the handle assembly  102 . 
         [0059]    The shaft section  104  mechanically connects the handle assembly  102  to the clip assembly  106  and, together with the clip assembly  106 , is designed to be inserted into a lumen of an endoscope. As shown in  FIGS. 3 and 4 , the shaft section  104  comprises an outer flexible coil  130  which is designed to transmit a torque from the proximal end to the distal end of the device  100  and to provide structural strength to the shaft section  104 . The coil  130  may be a conventional coil used in biopsy devices and may, for example, comprise a single, coiled wire. The coiled wire may have a round, square or a rectangular cross section, and may be made of a biocompatible material such as, for example, stainless steel. Additional protective and low friction outer layers may be included on the shaft section  104 , according to known methods of construction. 
         [0060]    The control wire  118  transmits mechanical force applied to the handle  102  to the clip assembly  106 . The control wire  118  has a proximal end which is attached to a movable part of the handle  102 , such as the sliding spool  110 , using known methods. Stainless steel or other high yield biocompatible materials may be used to manufacture the control wire  118 , so that the structural integrity of the assembly is maintained. It is also important to prevent stretching of the control wire  118  when under tension since, if the wire stretches, the handle  102  will have to travel a greater distance to carry out a desired operation. As shown in  FIG. 5 , the distal end of the control wire  118  ends in a ball  140  which is used to connect the control wire  118  to the appropriate elements of the clip assembly  106 , as will be described below. In this embodiment, the diameter of the control wire  118  is substantially constant from a proximal end thereof to a proximal end of a distal tapered section  144 . The ball  140  may have a diameter which is greater than the diameter of the control wire  118 , to facilitate attachment to a yoke  204 . The control wire  118  may extend the length of the device  1   00 , from the yoke  204  to the sliding spool  110 , and may be designed to slide longitudinally along the device  100 . It may be made, for example, of stainless steel or other biocompatible metal. 
         [0061]    The control wire  118  may also include a reduced diameter section  142  designed to fail when a predetermined tension is applied thereto through the handle assembly  102 . The tapered section  144  may be used to transition between the main body of the control wire  118  and the reduced diameter section  142 , without steps or other discontinuities which may concentrate stress and make the fracture point more unpredictable. As will be described in greater detail below, one purpose of the reduced diameter section  142  is to facilitate the release of a hemostatic clip from the hemostatic clipping device  100  once the clip has been properly deployed. It will be apparent to those of skill in the art that the location of the reduced diameter section  142  the along control wire  118  may be varied to take into account specific requirements of the device  100 . 
         [0062]    An inner sheath  132  may be used in the construction of the shaft section  104 , as shown in  FIGS. 3 and 4 . The inner sheath  132  provides a low friction bearing surface disposed between the outer diameter of the control wire  118 , and the inner diameter of the shaft section  104 . The inner sheath  132  may be formed of a low friction material such as, for example, Teflon™, HDPE or Polypropylene. In one exemplary embodiment, the inner sheath  132  is slidable within the shaft section  104 , and the control wire  118  is slidable within the inner sheath  132  forming a low friction system of multiple bearing surfaces. To further reduce friction, a bio-compatible lubricant may be applied to the inner and outer surfaces of the inner sheath  132 , along the length of the shaft section  104 . For example, silicone lubricants may be used for this purpose. 
         [0063]    A slidable over-sheath  150  may be included in the design of the shaft section  104 , as shown in  FIGS. 1 and 2 . The over-sheath  150  is designed to protect the inner lumen of the endoscope from the metal clip assembly  106  and from the metal coil  130  while the hemostatic clipping device  100  passes through the endoscope&#39;s lumen. After the clipping device  100  and, more specifically, after the clip assembly  106  has passed through the endoscope, the over-sheath  150  may be withdrawn to expose the distal portion of the clipping device  100 . The over-sheath  150  may be formed, for example, as a single lumen plastic extrusion element slidable over the distal portions of the clipping device  100  to selectively cover and uncover the clip assembly  106 . In one embodiment, the over-sheath  150  is formed of a low friction polymer such as, for example, Teflon™, HDPE, Polypropylene, or similar materials. 
         [0064]    The over-sheath  150  may include a grip portion  152  and an elongated body  154 . The grip portion  152  is designed as a handle making it easier for the user to slide the over-sheath  150  over the shaft of the clipping device  100 . In one exemplary embodiment, the grip portion  152  is made of a rubber-like material to provide a good gripping surface for the user. For example, an injection moldable polymer such as TPE may be used to construct the grip portion  152 . The elongated body  154  may be formed as a substantially cylindrical shell surrounding the shaft of the clipping device  100 . The elongated body  154  may be attached to the grip portion  152  using conventional methods as would be understood by those skilled in the art. 
         [0065]    As shown in  FIGS. 6 and 7 , an exemplary grip portion  152  comprises a central hollow channel  160  that may be used to receive the shaft of the clipping device  100 . The central hollow channel  160  is aligned with the elongated body  154  to provide a continuous channel containing the shaft of the clipping device  100 . The material of the grip portion  152  may have a high coefficient of friction, so that an interference fit is possible between the central hollow channel  160  and the shaft of the clipping device  100  without the use of adhesives or mechanical fastening devices. In one embodiment, friction bosses  158  may be provided on an inner diameter of the hollow channel  160  to provide additional friction between the shaft of the clipping device  100  and the over-sheath  150  assembly. The friction bosses  158  may be formed, for example, as protrusions extending from the inner diameter of the over-sheath  150  and may have a variety of stubby or elongated shapes. The amount of friction between these two components may be balanced so that no unwanted relative movement takes place while, at the same time, making it relatively easy for the user to slide the over-sheath  150  proximally and distally when necessary. 
         [0066]    A sheath stop  156  may be provided for the clipping device  100  to prevent the over-sheath  150  from sliding away from the distal end while the clipping device  100  is inserted in the endoscope. As shown in the exemplary embodiment of  FIGS. 2 and 8 , the sheath stop  156  physically blocks the grip portion  152  from sliding proximally to prevent the over-sheath  150  from being withdrawn and exposing the clip assembly  106 . The sheath stop  156  is designed to easily snap in place near the proximal end of the shaft section  104  where it can be reached and manipulated by the operator during the surgical procedure. Once the clip assembly  106  has been inserted in the endoscope and has reached the desired location in the patient&#39;s body, the sheath stop  156  may be removed from the shaft section  104  so that the user can move the grip portion  152  proximally to uncover the clip assembly  106 . 
         [0067]    The connection between the sheath stop  156  and the shaft section  104  may include, for example, pairs of opposing fingers  162 ,  164  that are designed to snap over the shaft section  104 . The fingers  162 ,  164  cooperate to securely and releasably hold the body of the shaft section  104  therebetween. The fingers  162 ,  164  respectively comprise guide portions  170 ,  172 ; shaft channel portions  166 ,  168 ; and blocking portions  174 ,  176 . Insertion of the sheath stop  156  on the elongated body  154  is accomplished by pressing the body of the shaft section  104  between the guide portions  170 ,  172 , to spread the fingers  162 ,  164  and allow further insertion of the shaft  104  between the fingers  162 ,  164 . The guide portions  170 ,  172  and the blocking portions  174 ,  176  are shaped so that insertion of the shaft section  104  towards the channel portions  166 ,  168  requires less effort than moving the shaft section  104  in the opposite direction. 
         [0068]    Once shaft section  104  has been placed within the channel portions  166 ,  168 , the fingers  162 ,  164  snap back to their non-spread position and retain the shaft section  104  in place therebetween. The shaft section  104  is removed by pulling the sheath stop  156  away from the shaft section  104 . Due to the shape of the blocking portions  174 ,  176 , removing the shaft section  104  requires the application of more force than does insertion thereinto. Stops  180  may also be provided on the sheath stop  156  to limit the movement of the shaft section  104  towards the grasping portion  161  to prevent damage to the device that may be caused by excessive spreading of the fingers  162 ,  164 . The sheath stop  156  may be formed of a resilient material, such as a polymer, and may be manufactured by injection molding. 
         [0069]    The clip assembly  106  is disposed at the distal end of the clipping device  100 , and contains the mechanism that converts the proximal and distal movement of the control wire  118  into the actions necessary to deploy and release a hemostatic clip  90 .  FIGS. 9 ,  10  and  11  show, respectively, side, top and perspective views of the distal end of the clipping device  1   00 , including the clip assembly  106  having clips in the folded configuration. This configuration is used, for example, to ship the clipping device  100  and to insert the clipping device  100  through the lumen of an endoscope. Some of the components of the clip assembly  106  include a capsule  200  which provides a structural shell for the clip assembly  106 , the clip arms  208  which move between open and closed positions, a bushing  202  attached to the distal end of the control wire  118 , and a yoke  204  adapted to connect the capsule  200  to the control wire  118 . 
         [0070]    As depicted, the proximal end of the capsule  200  slides over the distal end of the bushing  202 . A locking arrangement between these two components is provided by capsule tabs  212 , which are designed to lock into the bushing  202  so that mechanical integrity is temporarily maintained between the capsule  200  and the bushing  202 . Within the capsule  200  are contained a yoke  204  and a tension member  206  which transmit forces applied by the control wire  118  to the clip arms  208 . The ball  140  formed at the distal end of the control wire  118  is mated to a receiving socket  210  formed at the proximal end of the yoke  204 . A male C-section  214  extending from the tension member  206  is received in a corresponding female C-section  216  formed in the yoke  204 , so that the two components are releasably connected to one another, as will be described below. The clip arms  208  in the closed configuration have a radius section  300  which is partially contained within the capsule  200  to prevent opening of the arms. Each of the clip arms  208  goes over the tension member  206  and has a proximal end  222  which slips under a yoke overhang  254 , to further control movement of the arms  208 . 
         [0071]      FIGS. 12 and 13  show a top and a perspective view of one exemplary embodiment of the clip assembly  106  in an open configuration with the clip arms  208  in a fully open position. The open configuration is obtained when the sliding spool  110  shown in  FIG. 1  is moved distally so that the ball  140  of the control wire  118  pushes the assembly containing the yoke  204  and the tension member  206  forward, sliding within the capsule  200 . As will be described below, the distal ends of the clip arms  208  are biased toward the open position and revert to this position whenever they are not constrained by the capsule  200 . In the exemplary embodiment, a maximum opening of the clip arms  208  occurs when the clip arms  208  ride over the folded distal folding tabs  220  which extend from the distal end of the capsule  200 , as shown in  FIGS. 14 and 15 . In this embodiment, the tabs  220  provide a cam surface, and the clip arms  208  act as cam followers, being deflected by the tabs  220 . In addition, the folding tabs  220  may also provide a distal stop for the tension member  206 , to retain it within the capsule  200 . Thus, by moving the sliding spool  110  distally, the user opens the clip arms  208  to prepare to grasp tissue therebetween. 
         [0072]    When the sliding spool  110  is moved proximally by the user, the assembly within the capsule  200  also moves proximally and the clip arms  208  are withdrawn within the capsule  200 . As the clip arms  208  move proximally within the capsule  200 , clip stop shoulders (CSS)  222  contact a distal portion of the capsule  200 , for example, the folded tabs  220 . This interaction of the CSS  222  with the capsule  200  provides to the user a first tactile feedback in the form of increased resistance to movement of the sliding spool  110 . This feedback gives to the operator a positive indication that further movement of the handle control will cause the hemostatic clip  90  to be deployed from the clip assembly  106 . The operator may then decide whether the current position of the clip  90  is acceptable or not. If the position is acceptable, the operator can deploy the clip  90  by continuing to move the sliding spool  110  with increased proximal pressure to cause the clip arms  208  to close on the tissue. If not, the operator can move the sliding spool  110  distally to re-open the clip arms  208  and extend them out of the capsule  200 , reposition the clip  90 , and repeat the above steps to close the clip  90  at a more appropriate location. 
         [0073]    When the user determines that the clipping device  100  is positioned correctly, the proximal pressure on the sliding spool  110  may be increased to continue deployment of the hemostatic clip  90  from the clip assembly  106 .  FIGS. 16 and 17  show respectively a top and side view of the clipping device  100  in this condition. As the proximal tension on sliding spool  110  is increased, the control cable  118  pulls the yoke  204  proximally, away from the tension member  206 . The tension member  206  is firmly attached to the clip arms  208  which are prevented from moving proximally by the interaction of the CSS  222  with the folded tabs  220 . If sufficient pulling force is applied to the yoke  204 , the male C section  214  of the tension member  206  yields and loses integrity with the female C section  216  of the yoke  204 . This can occur because, in the exemplary embodiment, the tension member  206  is formed of a material with a lower yield strength than the material of the yoke  204 . 
         [0074]    The force required to break the tension member  206  away from the yoke  204  may be tailored to achieve a desired feedback that can be perceived by the user. The minimum force required to break the tension member  206  free of the yoke  204  may be selected so that a tactile feedback is felt by the user, to prevent premature deployment of the hemostatic clip  90  while a maximum force may be selected so that other components of the linkage between the sliding spool  110  and the clip arms  208  do not fail before the male C section  214  and the female C section  216  disconnect from one another. In one exemplary embodiment, the tension force necessary to disconnect the two components may be in the range of approximately 4 lbf to about 12 lbf. This range may vary depending on the size of the device and the specific application. To obtain this force at the interface of the male and female C sections  214 ,  216  a larger force will be applied by the user at the sliding spool  110 , since friction within the device may cause losses along the long flexible shaft. 
         [0075]    When the male C section  214  of tension member  206  yields, several events take place within the exemplary device  100  nearly simultaneously. More specifically, the yoke  204  is no longer constrained from moving proximally by the CSS  222  abutting the capsule  200 . Thus the yoke  204  travels proximally until coming to rest against a distal bushing shoulder  250 . The tension member  206  is not affected by this movement since it is no longer connected to the yoke  204 . The proximal ends  252  of the clip arms  208  are normally biased away from a center line of the device  100  and are no longer constrained by the yoke overhangs  254 . Accordingly, the clip latches  302  are free to engage the latch windows  304  of the capsule  200 , thus maintaining the integrity of the capsule-clip arms combination after deployment. Details of one exemplary embodiment of the capsule  200  are shown in  FIGS. 14 ,  15  and details of the clip arms  208  are shown in  FIGS. 18 ,  19  and  20 . 
         [0076]    As the yoke  204  moves proximally to abut against the bushing  202 , the capsule tabs  306  are bent away from the centerline of the capsule  200  by the cam surfaces of the yoke  204 . As a result, the capsule tabs  306  are no longer engaged to the corresponding bushing undercuts  350 , shown in the side and perspective views of the bushing  202  depicted in  FIGS. 21 ,  22 . Since the capsule  200  and the bushing  202  (which is securely connected to shaft section  104 ) are no longer connected, the clip assembly  106  is prevented from being released from the shaft section  104  only by its connection to the ball  140  of the control wire  118 . 
         [0077]    A further result of moving the yoke  204  against the distal bushing shoulder  250  of the bushing  202  is that the distal end of the wire stop  360  (shown in  FIGS. 12 ,  16 ) is placed near the proximal bushing shoulder  364  (shown in  FIG. 22 ). The flared fingers  362  located at the distal end of the wire stop  360 , better shown in  FIG. 23 , are compressed as they pass through the central ID of the bushing  202 , but return to their normally biased open position (shown in  FIG. 23 ) after passing past the proximal bushing shoulder  364 . Further distal movement of the sliding spool  110  is thus prevented since that movement would engage the fingers  362  of the wire stop  360  with the proximal bushing shoulder  364 . This feature prevents the clip assembly  106  from being pushed away from the bushing  202  before the ball  140  is separated from the control wire  118 , as will be described below. 
         [0078]    The wire stop  360  comprises a tube with a first slotted and flared end attached to the control wire  118  by conventional means. As shown in  FIG. 23 , the slots impart flexibility to the device so it can easily pass through the central lumen of the bushing  202 . Flared fingers  362  are formed by the slots, and engage the proximal bushing shoulder  364 . The wire stop  360  is made of a material that is biocompatible and that has enough resilience so that the fingers  362  re-open after passage through the bushing  202 . For example, stainless steel may be used for this application. 
         [0079]    One feature of the exemplary embodiment of the invention described above is that the user receives both tactile and auditory feedback as the clip assembly  106  is deployed and released. The separation of the tension member  206  from the yoke  204  produces a small clicking noise and a tactile feel that is perceptible while holding the handle assembly  102 . The change in axial position of the sliding spool  110  is thus augmented by the changes in resistance to its movement and by the clicking sound and feel through the start and stop of the movement. As a result the user is always aware of the status of the clip assembly  106 , and the inadvertent deployment of a hemostatic clip  90  in an incorrect location is less likely. It will be apparent to those of skill in the art that the order of male and female connectors in the device may be reversed or changed without affecting the operation of the device. 
         [0080]    It may be beneficial for the user to be certain that the clip assembly  106  has been deployed before the rest of the clipping device  100  is removed from the endoscope. Injury to the tissue being treated could result if the clipping device  100  is removed from the operative site when the hemostatic clip  90  is only partially deployed. Accordingly, a large tactile feedback may be incorporated, to augment the auditory and tactile feedback stemming from the separation of the yoke  204  from the tension member  206 .  FIG. 24  depicts the condition where the clip assembly  106  separates from the rest of the clipping device  100 . According to the described embodiment, this second user feedback is obtained by designing the control wire  118  so that it will separate from the end ball  140  when a predetermined tension is applied to it. In other words, the ball  140  of the control wire  118  is mechanically programmed to yield and separate from the body of the control wire  118  when a pre-set tension is applied thereto. The size of the reduced diameter section  142  can be selected so that, when the user continues to move the sliding spool  110  proximally as the programmed yield tension is reached, the ball  140  detaches from the tapered section  144  and provides a large tactile feedback to the operator. 
         [0081]    When the ball  140  detaches, the sliding spool  110  bottoms out at the proximal end of the handle  108 , such that a full stroke of the handle assembly  102  is reached. The tension required to cause the reduced diameter section  142  to yield and release the ball  140  may vary over a range of values. However, for best results the force should be greater than the tension force required for the male C section member  214  to separate from the yoke  204 . If this condition is not satisfied, a situation may occur where the clip assembly  106  is locked in place on the patient&#39;s tissue, but cannot be released from the clipping device  100 . It will be apparent that this situation should be avoided. In one exemplary embodiment, the tension force required to separate the ball  140  from the body of the control wire  118  is in the range of between about 10 lbf and 20 lbf at the distal end of the control wire  118 . As discussed above, losses along the elongated flexible shaft may require the user to apply a force substantially greater than this to the handle body  102 . 
         [0082]    Once the ball  140  has separated from the rest of the control wire  118 , the user can pull the rest of the clipping device  100  from the endoscope. As this is done, the yoke  204  is retained within the capsule  200  by the spring and frictional forces of various features of the capsule  200 , such as the capsule tabs  306 . Prior to withdrawing the clipping device  100 , the over-sheath  150  may be moved distally by the user over the entire remaining portions of the shaft section  104  to prevent damage to the endoscope as the clipping device  100  is withdrawn therethrough. The sheath stop  156  may also be placed on the shaft section  104  proximally of the over-sheath grip  152  to prevent inadvertent sliding of the over-sheath  150  from the distal end of the device  100 . 
         [0083]    A more detailed description of several components of the clipping device  100  follows. The clip arms  208  are shown in detail in  FIGS. 18 ,  19  and  20 ; the tension member  206  is shown in side and top views in  FIGS. 25 ,  26 ; while top and side views of the yoke  204  are shown respectively in  FIGS. 27 and 28 . the clip arms  208  may be formed of a biocompatible material such as Nitinol, Titanium or stainless steel. Maximum spring properties may be obtained by using materials such as  400  series stainless or 17-7 PH. As shown, a tear drop keyway  400  is formed in the clip arm  208  to mate with a corresponding tear drop key  402  formed on the tension member  206 . This feature maintains the relative positions of these two components and of the yoke  204  substantially constant. The shape of the keyways  400  may be varied. For example, the keyway  400  may be oval or elliptical. Central portions of the clip arms  208  define a spring section  404 . When the proximal ends  252  of the clip arms  208  are under the yoke overhangs  254 , the clip arms  208  are allowed to pivot over the tension member  206 , which in turn biases the distal ends  252  towards the open configuration when no longer restrained by the capsule  200 . As a result, the proximal end  252  of each clip arm  208  springs upward and engages the latch windows  304  in the capsule  200 . 
         [0084]    the clip arms  208  also comprise a radius section  300  that adds strength to the clip and reduces system friction. The radius of the radius section  300  approximately matches the inner diameter of the capsule  200  and has a smooth profile to avoid scratching the inner surface of the capsule  200 . A pre-load angle α is defined between the radius section  300  and the spring section  404 . The pre-load angle α determines how much interference (pre-load) exists between the two opposing clip arms  208  at their distal ends when closed. The greater the pre-load angle α, the greater the engaging force that is applied by the clip arms  208 . However, this condition also causes the greatest system friction when the hemostatic clip  90  is closed. The clip arms  208  also comprise interlocking teeth  408  disposed at their distal ends. In the exemplary embodiment, the teeth  408  are identical so that the arms may be interchangeable and will mesh smoothly with the set facing them. The teeth  408  are disposed at a nose angle β which may be between approximately 90 and 135 degrees, but in other applications may be greater or lesser than the described range. 
         [0085]    One exemplary embodiment of the capsule  200  is shown in detail in  FIGS. 14 and 15  and comprises alignment keyways  500  that are designed to mate with corresponding features on the bushing  202  to rotationally align the two components. In this embodiment, the capsule tabs  306  may be bent towards the centerline of the capsule  200  to engage the bushing undercuts  350 . The engagement maintains the integrity between the capsule assembly  200  and the rest of the clipping device  100  until the yoke is pulled into the distal bushing shoulder. the capsule overhangs  502  provide added clamping strength to the deployed clip arms  208 . This is achieved by reducing the length of the portion of each clip arm  208  that is not supported by a portion of the capsule  200 . This feature does not affect the amount of tissue that may be captured by the clip arms  208  since the capsule overhangs  502  extend on a plane substantially parallel to the plane of the clip arms  208 . 
         [0086]    Additional features of the capsule  200  include an assembly aid port which may be used to assist in aligning the components of the clip assembly  106 . Bending aids  506  facilitate a smooth bend when the distal folding tabs  220  are bent inward, as described above. The bending aids  506 , as shown, are holes aligned with the folding line of the tabs  220 , but may also include a crease, a linear indentation, or other type of stress concentrator. The capsule  200  may be formed from any of a variety of biocompatible materials. For example, stainless steel, Titanium or Nitinol or any combination thereof may be used. High strength polymers like PEEK™ or Ultem™ may also be used to form the capsule  200 , with a heat set treatment being used to adjust positionable elements. 
         [0087]      FIGS. 25 and 26  depict additional details of the tension member  206 . As shown, tear drop keys  402  are designed to engage the tear drop keyways  400  of the clip arms  208 , as described above. Clip follower planes  508  are shaped to form a fulcrum which allows the clip arms  208  to rock between the open and closed configurations. The tension member  206  comprises a distal stop face  510  which abuts the distal folding tabs  220  of the capsule  200  to stop the distal motion of the capsule assembly  106 . In general, all surfaces and edges of the tension member  206  that are in contact with the inner surfaces of the capsule  200  preferably have a radius substantially similar to an inner radius of the capsule  200  to provide a sliding fit therein. The tension member  206  may be formed of a biocompatible polymer, monomer or thermoset. The type of mechanism selected to release the tension member  206  from the yoke  204  may determine the type of material used since a release due to fracture of the male C section  214  requires a relatively brittle material while release due to yielding without fracture calls for a softer material. 
         [0088]    Additional details of the yoke  204  are shown in  FIGS. 27-29 . When the control wire  118  is seated in the yoke  204 , it is desirable to ensure that it cannot inadvertently be removed from the control wire slot  600 . Accordingly, in the present embodiment the ball cavity  602  has a diameter sufficiently large to allow the ball  140  to pass therethrough while the wire cavity  604  is large enough to allow the control wire  118  to pass therethrough, but not large enough to allow the ball  140  pass therethrough. To assemble the control wire  118  with the yoke  204  according to the exemplary embodiment, the proximal end of wire  140  is inserted into the ball cavity  602  until the ball bottoms out, and then the control wire  118  is rotated until it is seated in the control wire cavity  604 , thus constraining further movement of the ball  140 . According to the present embodiment, the yoke  204  may be made of a biocompatible metal such as stainless steel or a high strength polymer such as Ultem™. 
         [0089]    According to embodiments of the present invention, the clipping device  100  may be scaled to fit the requirements of different surgical procedures. In one exemplary embodiment, the clipping device  100  may be sized to fit through an endoscope having a working channel diameter of approximately 0.110 inches. The exemplary bushing may have a length of about 0.22 inches and an OD of approximately 0.085 inches. The capsule may have a length of about 0.5 inches, an OD of about 0.085 inches, and a wall thickness of about 0.003 inches. When assembled, the rigid length of the capsule  200  and the bushing  202  is approximately 0.625 inches. This length is important because if it is too great, the assembly will not pass through the bends of the flexible endoscope. In the exemplary clipping device, the outer sheath may have an ID of approximately 0.088 inches and an OD of about 0.102 inches. The overall length of the clipping device may be approximately 160 inches, while the tissue grasping portion of the clip arms  208  may be approximately 0.4 inches long. 
         [0090]    In treating internal bleeding, and in particular to apply an hemostatic treatment to gastrointestinal bleeding, it is often necessary to apply more than one hemostatic clip to the injured tissue. Using conventional methods, the treatment involves repeatedly utilizing a single deployment clip apparatus, with the disadvantage of having to remove the old clipping device from the endoscope, prepare additional clipping devices, and re-inserting the additional clipping devices in the endoscope for each clip. After insertion in the endoscope, each additional device has to be re-positioned over the wounded tissue before the new clip may be deployed. Multi deployment clipping devices are also in use, but generally require the device to be removed from the endoscope so that a new clip may be loaded manually in the device. 
         [0091]    In a further embodiment of the present invention, a multiclip endoscopic hemostatic device may be used to discharge multiple hemostatic clips without the necessity to remove the device from the endoscope after each clip is deployed. The multiclip device achieves equal or better results than conventional single deployment clipping devices, while greatly facilitating the placement of multiple hemostatic clips in cases where a single hemostatic clip is insufficient. In one embodiment, the clips used by the multiclip device according to the present invention are substantially similar in size to conventional hemostatic clips, and thus can be used with conventional endoscopes. According to the invention, the cost of manufacturing the multiclip apparatus is sufficiently low to permit the units to be disposable, and be discarded after use with only one patient. 
         [0092]    According to the invention, the multiclip hemostatic clipping apparatus is used in a minimally invasive environment, such that it is applied to the surgical site through an endoscope. The distal end of the hemostatic multiclip device is inserted through the working lumen of the endoscope, and is brought in the vicinity of the surgical site where the bleeding occurs. For example, an endoscope having a working channel of at least about 1.8 mm inner diameter may be used to reach the surgical site. The proximal ends of the endoscope and of the hemostatic multiclip device are provided with hand controls used by the user/physician to operate the devices. 
         [0093]    The hemostatic multiclip device according to an exemplary embodiment of the present invention uses a magazine containing a plurality of hemostatic clips that is advanced through the endoscope&#39;s working lumen, to a location near the surgical site. The magazine may be attached to a sheath designed to protect the inner surfaces of the endoscope from damage caused by sharp edges of the magazine and clip assembly, and which extends beyond the magazine through the length of the endoscope. The hemostatic clips are joined in a clip chain which is inserted in the magazine, and is free to translate in the magazine within certain limits that will be described below. Each of the clips may be formed, for example, of sheet metal or of another material having appropriate mechanical and bio-compatibility properties. The material of the clips is selected to resist plastic deformation while constrained in the closed configuration, so that the hemostatic clips will return to the open configuration when not otherwise restrained. 
         [0094]    A modified version of the clipping device  100 , shown in  FIGS. 1 and 2 , may be used with the clip magazine and clip chain described above. A clip magazine containing multiple hemostatic clips may be inserted in the proximal end of the shaft section  104 , such that the clips are deployed from the distal end thereof. A handle  108  and sliding spool  110 , or similar implements, may be used in conjunction with a control linkage to operate the multiclip dispensing apparatus, as will be described in detail below. 
         [0095]      FIG. 31  shows an exemplary embodiment of a hemostatic clip according to the present invention. Exemplary clip  702  comprises two clip arms  704  which have inner facing surfaces adapted to grasp and retain tissue therebetween when placed in a closed configuration. In  FIG. 31 , the clip arms  704  are in the open configuration which is assumed by the clip  702  in the early phase of deployment, before the tissue is clamped. Clip  702  may be formed of two parts joined at the common portion  705 , or may be of a single piece construction. In the exemplary embodiment, clip  702  is biased in the open configuration (shown in  FIG. 31 ) prior to being loaded in the clip magazine. A sliding lock ring  706  may be used to lock clip arms  704  in the closed configuration, which is assumed by the clip  702  when it is clamped to the tissue. In different exemplary embodiments, the sliding locking ring  706  may be replaced by different devices adapted to lock clip arms  704  in the closed configuration. 
         [0096]    As indicated above, a plurality of clips may be loaded in the magazine for use with the hemostatic multiclip device according to the present invention.  FIG. 32  shows an exemplary embodiment of a clip chain according to the invention. Clip chain  700  is formed by joining hemostatic clips  702  to one another using, for example, a linking feature  708 . Linking feature  708  may comprise an attachment which retains the two joined clips  702  together as long as there is no movement of the joined clip ends in a direction perpendicular to the longitudinal axis of the clips. In this manner, the clip chain  700  remains intact as long as the clips are translated in a direction generally along the longitudinal axis of the clips. One clip may be released, however, by moving the appropriate clip end along a diameter of the device, that is in a direction perpendicular to the longitudinal axis. For example, linking feature  708  may be clamped between the distal ends of clip arms  704  which are held in the closed configuration. Linking feature  708  may be formed integrally with the body of hemostatic clip  702 , or may be an optional addition that may be attached to more conventional clips. 
         [0097]    An exemplary clip magazine  720  is shown in perspective view in  FIG. 36 . Clip chain  700  (shown in perspective view in  FIG. 35 ) may be inserted longitudinally in the hollow channel  722  of magazine  720 , as shown in  FIG. 38 . Magazine  720  may be a generally cylindrical structure located at the distal end of the hemostatic multiclip device, which contains a portion or all of the clips  702  within the clip chain  700 . Magazine  720 , together with clip chain  700 , forms a capsule having dimensions and sufficient flexibility to comply with the curvature of the endoscope&#39;s working channel. Compliance features  723  may be used to impart flexibility to the body of magazine  720 , and for example may comprise circumferential slits. A control link  726  may enter a proximal opening  722  of the clip magazine  720 , opposite from the distal end  724 . 
         [0098]    The most proximal of the clips  702  may be connected to control link  726  in a releasable manner. Control link  726  may be designed to carry compression and tension loads, so that clip chain  700  may be translated in both directions through forces transmitted by control link  726 . Control link  726  may be formed by a rigid tube, a semi rigid wire, or by any other structural element capable of transmitting tension and compression loads along the length of the hemostatic multiclip device. Control link  726  may be connected to a control handle at the proximal end, to give to the surgeon control of the clip&#39;s deployment. 
         [0099]      FIG. 30  shows a detail of the connection between the control link  726  and the most proximal hemostatic clip  702 . In this embodiment, control link  726  is a rod or tube which terminates in a connector portion  727  adapted to push against linking element  708 . Connector portion  727  may also be designed to apply a tension force to the linking element  708 , in a known manner. A sheath  725  may be used to encapsulate control link  726 , to protect the working channel of an endoscope from damage, and to reduce friction between the moving control link  726  and the clip magazine  720 . 
         [0100]    A control handle portion of the hemostatic multiclip device (not shown) is provided at the proximal end of the device, extending outside of the proximal end of the endoscope. The control portion may be similar to that shown in  FIG. 1 , and may comprise hand controls which operate the control link  726  to cause the deployment and the release of the successive clips  702 . For example, hand movements of the surgeon may be transformed within the control portion into longitudinal movements of the control link  726  along the working channel of the endoscope. In an exemplary embodiment, clip chain  700  is rigid in compression and supports tensile loads, at least while contained within the clip magazine  720 . Clip chain  700  can therefore be translated along magazine  720  via movement of the control link  726 . 
         [0101]    As shown in  FIG. 38 , the clip chain  700  is formed of hemostatic clips  702  which remain attached to one another while they are within the cylindrical containment of the clip magazine  720 . Clip magazine  720  supports and constrains the clips  702  of the clip chain  700  in the radial direction through a large portion of its length. This prevents pairs of adjacent clips  702  from disconnecting, by not allowing relative radial movement between two clips. In particular, the radial movement of the substantially closed clip arms  704  of a first hemostatic clip is prevented, so that the linking feature  708  of a second clip, adjacent to the first clip, is not released. The exemplary design of clip chain  700  helps to minimize the width of the device, since it is only as wide as the width of the clips themselves. 
         [0102]    The diameter of clip chain  700  works in conjunction with the shape of the distal end  724  of clip magazine  720  to control the position of the distal portion of clip chain  700  through the distal end  724 . As shown in  FIG. 37 , magazine  720  has a reduced cross section portion  730  designed to limit the diameter of what passes therethrough. Specifically, reduced cross section  730  allows the passage of a single clip unattached to another clip at its distal end. However, reduced cross section  730  does not allow passage of a pair of connected clips. This is because the diameter of two connected clips is greater than the diameter of a single clip. In the exemplary embodiment that is due to the clip arms  704  not closing fully when they lock unto the linking feature  708  of another clip  702 , resulting in a greater distal tip diameter of the clip. 
         [0103]    The function of the clip chain  700  is better shown in  FIGS. 39 ,  40 , where a clip  702 ′ is placed to lead the clip chain  700  through the distal end  724  and through cross section reduction  730 . As the control element  726  is pushed distally, clip chain  700  is pushed distally until its second most distal clip  702  is stopped by reduced cross section  730 , at a position where the most distal clip  702 ′ is outside of magazine  720 , and is biased in the open configuration ready to grasp the tissue. In  FIG. 39 , the most distal hemostatic clip  702 ′ is being pushed outside of clip magazine  720 , past the distal end  724 . As the control link  726  continues to push distally, clip arms  704  of the second most distal clip  702  of chain  700  abut the reduced cross section  730  ( FIG. 40 ). At this point the single distal clip  702 ′ is largely outside of magazine  720 , and its clip arms  704 ′ take the open configuration since they are no longer constrained by magazine  720 . 
         [0104]    Once the user has placed the open clip  702 ′ over the desired location on the tissue, control link  726  is pulled proximally, so that clip chain  700  (including the most distal clip  702 ′) is pulled back into magazine  720 , as shown in  FIG. 41 . Clip sliding lock ring  706  is held distally by lock ring anti-pull back tabs  734 , as distal clip  702 ′ is pulled proximally. This causes lock ring  706  to move partially over clip arms  704 ′ and lock them in the closed configuration, to firmly grasp the tissue held within clips arms  704 ′. At this point the most distal hemostatic clip  702 ′ is clamped securely over the tissue, but is still attached via linking feature  708  to the clip chain  700 . 
         [0105]    After deployment and clamping of the most distal hemostatic clip  702 ′ is achieved, further proximal movement of the control linkage  726  causes separation of clip  702 ′ from clip chain  700 . Additional features may be formed on the clip  702 ′ or on the lock ring  706  to cooperate with distal end  724  and prevent further proximal movement of the distal clip  702 ′ relative to magazine  720 . The pull back distance of distal clip  702 ′ may be controlled, for example by properly positioning the additional feature  733 , so that the link between the most distal clip  702 ′ and the next to most distal clip  702  is located in a relief portion  732  of the distal end  724 . Relief portion  732  may be a movable tab or opening which allows local diametrical expansion of the clips within that portion of magazine  720 . 
         [0106]    As continued proximal tension force is applied by control link  726 , clip arms  704  of the second most distal clip  702  are pushed diametrically outward over the interlock feature  708  of the most distal hemostatic clip  702 ′, which now acts as a cam surface. Relief portion  732  of the clip magazine  720  allows the outward expansion due to the outward movement of clip arms  704  over linking feature  708 , thereby permitting clip arms  704  to continue moving proximally and separate from distal-most clip  702 ′. In other words, the separation of the two adjacent clips is caused by the force in the diametrical direction resulting from clip arms  704  being forced over clip lock feature  708  of distal clip  702 ′, and this force overcoming the bias of relief portion  732 . Distal most clip  702 ′ is still prevented to further move proximally by the additional feature  733  described above, but is now free to move distally and exit magazine  720 . 
         [0107]      FIG. 42  depicts the situation where the “former” most distal hemostatic clip  702 ′ has been ejected from clip magazine  720 , and is clamped securely to the target tissue. A “new” most distal hemostatic clip  702  has been pushed partially out of magazine  720 , and its clip arms  704  are in the open configuration, outside of distal portion  724 . The new most distal clip  702  is still connected to another clip  702  which is fully inside of clip magazine  720 , and is part of clip chain  700 . The user may at this point position open clip arms  704  over the desired tissue, and repeat the process described above to clamp clip arms  704  over the tissue, lock them closed, and release the new distal-most clip  702  from the clip chain  700  and from clip magazine  720 . 
         [0108]    To release the most distal clip  702 ′ from the clip chain  700 , the clip arms  704  belonging to the clip  702 , adjacent to the clip  702 ′, have to disengage from the linking feature  708 ′. To do so, the distal tip of clip arms  704  has to open at least sufficiently to clear the linking feature  708 ′ of the most distal clip  702 ′. The clip  702  is contained within the magazine  720 , which because of its radially rigid construction, for the most part prevents the clip arms  704  from opening. The only time that the clip arms  704  can open and release the linking feature  708 ′ is when the distal tips  705  of the clip arms  704  are substantially aligned with a section of the magazine  720  which either is radially wider, or is designed to yield when pressed by the clip arms  704 . For example, the relief portion  732  may comprise a cut out opening or a non-rigid portion of the magazine&#39;s wall, dimensioned to accommodate the tips  705  of the clip arms  704 . 
         [0109]    The utility of the multi clip deployment device according to the invention may be increased by configuring the multi-clip magazine so that the release of the linking feature  708 ′ from clip arms  704  can be performed more easily. In an additional exemplary embodiment shown in  FIG. 43 , the magazine  800  is formed with an expanded section  804  which extends  360  degrees around the circumference of the magazine  800 . The expanded section  804  formed by the wall of the magazine  800  defines an expanded chamber  810  within the lumen of magazine  800 . The expanded chamber  810  provides for sufficient room within the magazine  800  to allow distal tips  705  of the clip arms  704  to move radially outwards, as the clip arms  704  open to pass over the linking feature  708 ′. 
         [0110]    The deployment of the most distal clip  702 ′ from the exemplary magazine  800  is in many respects similar to the deployment from the magazine  720 , described above. A control link  726  may be used to transfer commands from the surgeon to the clip deployment mechanism in the form of proximal and distal translation of the link  726 . The most distal clip  702 ′ is initially connected to a clip chain  700 , and may be translated forward and backwards while still connected to the adjacent clip  702 . After the surgeon places the distal end of clip  702 ′ in position over the target tissue  822 , the most distal clip  702 ′ is pulled back inside the magazine  800 , so that clip arms  704 ′ close over a portion  820  of the target tissue  822 . The lock ring  706 ′ may be pushed distally by distal lip  806  of the magazine  800 , to lock the clip arms  704 ′ in the closed position around the target tissue portion  820 . 
         [0111]    After the most distal clip  702 ′ is clamped and locked in the closed position around the portion of target tissue  820 , further proximal movement of the clip  702  causes the distal clip  702 ′ and its adjacent clip  702  to detach. For the purposes of this discussion, clip  702  is referred to as the next-to-most distal clip. More specifically. The distal ends  705  of the adjacent clip&#39;s arms  704  partially open to pass over the linking feature  708 ′ of the most distal clip  702 ′, under the traction applied by the control linkage  726  which pulls clip  702  proximally. As described above, the most distal clip  702 ′ is prevented from moving proximally by the shape of the distal end  806  of the magazine  800 , so that a tension exists between the most distal clip  702 ′ and the next-to-most distal clip  702 . As the clip  702  moves proximally, linking feature  708 ′ acts as a cam forcing the clip arms  704  to open. The expanded chamber  810  allows the radial opening of the clip arms  704 , which releases the linking feature  708 ′. 
         [0112]    The magazine  800  provides several benefits to the multi-clip deployment device according to the present invention. Since the expanded section  804  is a radial bulge which spans 360 degrees around the circumference of the magazine  800 , the rotational orientation of the clip chain  700 , which includes clips  702  and  702 ′, within the magazine  800  is not important. The surgeon therefore has greater liberty to orient the distal clip  702 ′ as necessary to best perform the procedure. The rotational orientation of the clip chain  700  may be changed relative to the orientation of the magazine  800  and of the entire multi-clip delivery device to which the magazine  800  is attached, to better align the clip with the target tissue. This configuration simplifies the clip deployment procedure and makes the entire procedure simpler and less time consuming. In addition, manufacturing of the magazine  800  can be simpler, since there is no need to process the magazine to form radial relief regions such as relief portions  732 , or to cut openings in the wall of the magazine  800 . 
         [0113]    An exemplary clip deployment sequence from a magazine  800  according to the present invention is described below.  FIGS. 44-48  are used to depict the deployment of a most distal clip  702 ′ from the magazine  800 .  FIG. 44  depicts a pre-deployment configuration of the most distal clip  702 ′ from the magazine  800 , such that the clip arms  704 ′ are completely within the distal portion  802  of the magazine  800 . In this configuration, the linking feature  708 ′ is being grasped by the clip arms  704  of the clip  702 , such that the two clips  702 ,  702 ′ are connected in the clip chain  700 . The lock ring  706 ′ is away from the clip arms  704 ′, and does not yet constrain them in the closed configuration. In this step of the deployment, the surgeon may position the distal tip  802  of the magazine  800  in proximity of the target tissue, while preparing to clamp the clip  702 ′ to that tissue. 
         [0114]    As the control link  726  is pushed distally during a distal stroke of the deployment sequence, clip  702 ′ is pushed outside of the magazine  800 , as shown in  FIG. 45 . In this configuration, the arms  704 ′ of clip  702 ′ are no longer constrained by the walls of the magazine  800 . The lock ring  706 ′ is still near the clip&#39;s proximal end, held by the tip  802  within the magazine  800 , so that the clip arms  704 ′ are free to move to the open configuration. At this point, the clips  702 ,  702 ′ are connected by means of the linking feature  708 ′, and are free to rotate 360 degrees in any rotational orientation within the magazine  800  to facilitate proper orientation relative to the tissue to be clamped. Using the ability to place the clip  702 ′ in any desired rotational orientation, the surgeon can orient the clip arms  704 ′ in any desired position over the target tissue  820 , so that closing the clip arms causes the tissue to be clamped as effectively as possible. 
         [0115]    When the clip arms  704 ′ are correctly placed in the proper orientation over the target tissue  820 , the surgeon may continue the deployment by carrying out a proximal stroke of the deployment sequence. This causes the control link  726  to move proximally, thus entraining clip  704  and clip  704 ′. As described in the context of other embodiments, the proximal stroke of control link  726  causes the clip arms  704 ′ to close, and clamp on the portion  820  of the target tissue  822 . Distal end  802  of the magazine  800  forces the clip arms  704 ′ to close as clip  702 ′ moves proximally inside of the magazine  800 , such that the target tissue is clamped, as shown in  FIG. 46 . The lock ring  706 ′ is held near distal tip  802  by protrusions within magazine  800 , and slides distally over the clip arms  704 ′ as they are pulled proximally within the magazine  800 . In this manner, the clip arms  704 ′ are securely locked in the closed configuration by ring  706 ′, and are clamped on the target tissue. After the clip arms  704 ′ are locked in the closed configuration on the target tissue, the magazine  800  and the rest of the device can be rotated relative to the clips  702 ,  702 ′, since these are free to turn 360 degrees within the magazine  800 . 
         [0116]    Continued proximal tension on the control link  726  causes the clip  702  to further move proximally within the magazine  800 .  FIG. 47  depicts this step of the clip deployment process. However, the most distal clip  702 ′ is prevented from further proximal movement by the lock ring  706 ′ interacting with the protrusions formed at the distal end  802  of the magazine  800 . Lock ring  706 ′ is also prevented from moving too far distally over the closed clip arms  704 ′ by ring stops  705 . Accordingly, clip arms  704  are pushed apart by the linking feature  708 , which acts as a cam as the tip of clip arms  704  pass over it. The expanded chamber  810  defined by the expanded section  804  of magazine  800  gives sufficient room to the clip legs  704  to open and pass over the linking element  708 ′, so that the clip  702  can disengage from the clip  702 ′. Expanded section  804  extends 360 degrees around the circumference of the magazine  800 , so that the orientation of clips  702 ,  702 ′ within the magazine  800  is not important. This makes it possible for the surgeon to change the rotational orientation of the clip  702 ′ relative to the magazine  800  throughout the deployment steps, to maintain the desired orientation between the clip  702 ′ and the target tissue  822 . 
         [0117]      FIG. 48  depicts the final step of the clip deployment sequence, in which the clip  702 ′ is released from the magazine  800  and is left clamped to the target tissue. In this step, control link  726  may be again moved distally, to push clips  702  and  702 ′, which are now disconnected. As shown, clip  702 ′ is pushed outside of the magazine  800  by the distal portion of clip  702 , until it is ejected from the magazine  800 . Clip  702  now becomes the most distal clip present in the magazine  800 , and the same steps described relative to carry out the deployment of clip  702 ′ may be repeated to deploy the new clip  702 . Although the drawings depict a magazine  800  containing only two clips  702  and  702 ′, it will be apparent to those of skill in the art that additional clips may be connected in the same manner within magazine  800 , to form a longer clip chain  700 . 
         [0118]    As described, the distal most clip  702 ′ after release from the clip chain  700 , or more simply from clip  702 , may exit clip magazine  800  due to the tension applied to it by the clamped tissue. Alternatively, clip  702 ′ may be pushed out by the distal movement of clip  702 , as it is pushed towards the distal end  802 . The surgeon may ensure a complete release of clip  702 ′ by causing the control link  726  to move distally, for example by manipulating the hand control of the device. Conventional methods may be used to transform the hand movements of the surgeon into translation of the control link  726 , and to carry out the initial distal stroke and the subsequent proximal stroke. 
         [0119]    The present invention has been described with reference to specific exemplary embodiments. Those skilled in the art will understand that changes may be made in details, particularly in matters of shape, size, material and arrangement of parts without departing from the teaching of the invention. Accordingly, various modifications and changes may be made to the embodiments without departing from the broadest scope of the invention as set forth in the claims that follow. The specifications and drawings are, therefore, to be regarded in an illustrative rather than a restrictive sense.

Technology Classification (CPC): 0