Abstract:
Medical device used to cause hemostasis of blood vessels using a clip arrangement delivered to a target region through an endoscope. Method for using the device to cause hemostasis of a blood vessel through an endoscope. Medical device including a reversibly closeable clip, a locking arrangement, a control wire, a sheath, and a handle with an actuating trigger. Through the endoscope, hemostatic clipping device that is fully reversible and lockable. Hemostatic clip that reversibly targets and clips bleeding ulcers.

Description:
PRIORITY CLAIM 
     The present application is a Continuation of U.S. patent application Ser. No. 13/863,494 filed on Apr. 16, 2013; which is a Continuation of U.S. patent application Ser. No. 13/606,854 filed on Sep. 7, 2012; which is a Continuation of U.S. patent application Ser. No. 13/009,094 filed on Jan. 19, 2011 now U.S. Pat. No. 8,444,660; which is a Continuation of U.S. patent application Ser. No. 11/036,421 filed on Jan. 14, 2005 now U.S. Pat. No. 7,879,052; which is a Divisional of U.S. patent application Ser. No. 09/971,488 filed on Oct. 5, 2001 now U.S. Pat. No. 7,094,245. The entire disclosure of these applications are expressly incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to compression clips, and more specifically, to compression clips used to cause hemostasis of blood vessels located along the gastrointestinal tract delivered to a target site through an endoscope. 
     BACKGROUND 
     Gastrointestinal (“GI”) bleeding is often associated with peptic ulcer disease (PUD) and can be fatal if not treated immediately. Hemorrhaging is the most dangerous procedure with which a Gastro-Intestinal Endoscopist has to deal. It is his/her only unplanned, emergency procedure where time is critical in determining the outcome. It is also the one problem the Endoscopist faces that is generally not an outpatient procedure. A bleeding PUD can be a critical clinical event as there is internal hemorrhaging. Ulcers are classified from clean to active spurting bleeding. The most worrisome are active bleeders and visible vessels. Untreated visible vessels are likely to bleed. 
     Suspected bleeding PUD patients can be diagnosed and treated endoscopically in an emergency room, an ICU or the GI suite. Surgery generally results in higher cost, morbidity and mortality than endoscopy. Therefore, laparoscopy or open surgery is not preferred unless there is no endoscopic alternative or endoscopy has failed. If the diseased tissue is beyond repair, a surgical gastric resection may be performed. 
     Currently, the endoscopist has two commonly used treatments and some lesser used therapies to achieve hemostasis of the ulcer. The most widely used treatments are thermal therapy and injection therapy. Some of the less common options are Olympus Endoclips, lasers and argon plasma cautery. 
     With thermal therapy, a catheter with a rigid heating element tip is passed through the working channel of an endoscope after the bleed is visualized and diagnosed. After the rigid catheter tip has exited the scope, the scope is manipulated to press the tip against the bleed site. Thermal power is applied, either through a resistive element in the tip or by applying RF energy through the tissue, thus desiccating and cauterizing the tissue. The combination of the tip compressing the tissue/vessel and the application of heat theoretically welds the vessel closed. 
     Although thermal treatment is fairly successful in achieving hemostasis, it often takes more than one attempt (irrigation is applied after the initial treatment to see if hemostasis has occurred) and there is frequent re-bleeding. Generally several pulses of energy are applied during each attempt. If early re-treatment is needed, there is a risk of perforation with the heat probe. Another disadvantage is that both types of thermal therapy require a specialized power generator and the equipment can be expensive. 
     With injection therapy, a catheter with a distally extendable hypo needle is passed through the working channel of the endoscope after the bleeding has been visualized and diagnosed. Once the catheter tip has exited the scope, the scope is manipulated to the bleed site, the needle is extended remotely and inserted into the bleed site. A vasoconstricting (narrowing of blood vessels) or sclerosing (causing a hardening of tissue) drug is then injected through the needle. Multiple injections in and around the bleeding site are often needed, until hemostasis has been achieved. As with thermal therapy, re-bleeding is also a problem. 
     The treatment used in any specific instance is highly dependent on geographic region. In some regions, especially in the United States, injection therapy is often combined with thermal treatment since neither therapy is completely effective alone. 
     The primary success rate of endoscopic treatment is about 90%. The other cases are usually referred to surgery. All identified ulcers may re-bleed at a later time, but the re-bleed rate for endoscopically treated active bleeds and a visible vessel is 10-30%. Even with the introduction of new treatments and devices, these rates have not improved significantly in decades. Surgery&#39;s short and long-term success for permanent hemostasis is virtually 100%. 
     Surgery has a higher success rate because the bleeding site is compressed mechanically, causing better hemostasis. Using devices such as clamps, clips, staples, sutures (i.e. devices able to apply sufficient constrictive forces to blood vessels so as to limit or interrupt blood flow), the bleeding vessel is ligated or the tissue around the bleed site is compressed, ligating all of the surrounding vessels. 
     An existing device that incorporates the advantages of surgery into a less-invasive endoscopic procedure is the Olympus EndoClip. The goal of the device is to pinch the bleeding vessel to create hemostasis. The problem with this device is that once jaw closure begins, it is not possible to reopen them, and the endoscopist is committed to firing the clip. In other words, jaw closure is not reversible. Because the vessel is frequently difficult to see, often several clips must be deployed in order to successfully pinch the vessel and achieve hemostasis. Additionally, the Olympus EndoClip is a semi-reusable device, causing the performance of the device to degrade with use. 
     SUMMARY OF THE INVENTION 
     The present invention provides medical devices for causing the hemostasis of blood vessels located along the gastrointestinal tract. The goal of the invention is to give the endoscopist a technique and device which: 1) has a success rate in line with the surgical option; 2) is easier to set-up than the Olympus EndoClip; and 3) is easier to deploy than the Olympus EndoClip. The design intent is to eliminate surgery and its associated mortality and morbidity. 
     The medical devices of the present invention include: a compression clip used to cause hemostasis of blood vessels and a mechanism for deploying the clip that includes an arrangement for closing the clip and for reversing the closing process to reopen the clip after closure has begun. Embodiments of the invention may include a lock arrangement for locking the clip closed; a control wire connected to the clip and able to be disconnected from the clip; an axially rigid sheath enclosing the control wire and communicating a compressive force opposing a tensile force of the control wire; a handle connected to the axially rigid sheath; and/or a trigger enclosed within the handle and engaging the control wire to close and lock the clip and to uncouple the control wire from the clip. 
     There are several key advantages of the invention disclosed here over existing devices. The device&#39;s ability to repeatedly open and close the clip until the desired tissue pinching is accomplished will lead to a quicker procedure, requiring less clips to be deployed, with a higher success rate. In particular embodiments, this higher success rate will be improved even more due to the device&#39;s ability to be easily rotated so that the clip legs can be adjusted relative to the bleeding vessel. In particular embodiments, the time required to perform the overall procedure will also be further reduced due to the fact that the device is completely set up, with the clip already attached to the delivery device, unlike the competitive device. A more robust delivery device may allow a larger, stronger clip to be delivered. Combinations of these features will provide for a device that is easier to use. 
     Another advantage inherent to particular embodiments of this design is the feature of being completely disposable. The competitive device, the Olympus Endoclip, uses a “semi-reusable” delivery device, capable of firing several clips before it fails. This causes the device&#39;s functionality to degrade over the course of its use, until it is no longer able to deploy a clip. The competitive delivery device must be loaded manually, which is cumbersome to the operator and time-consuming, especially in the context of an unplanned emergency procedure. The “single-use” (disposable) embodiments of the invention disclosed here would function the same with each clip, in each procedure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an enlarged partial view of a first embodiment of the medical device of the present invention. 
         FIG. 2  is an enlarged partial view of the distal end of the embodiment of  FIG. 1 . 
         FIG. 3  is an enlarged view of the clip of the embodiment of  FIG. 1 . 
         FIG. 4  is an enlarged view of the lock sleeve of the embodiment of  FIG. 1 . 
         FIG. 5  is an enlarged view of the j-hook of the embodiment of  FIG. 1 . 
         FIG. 6  is an enlarged partial view of the control wire, retainer, and clip of the embodiment of  FIG. 1 . 
         FIG. 7  is an enlarged partial view of the handle of the embodiment of  FIG. 1 . 
         FIG. 8A  is an enlarged partial view of the distal end of another embodiment of the medical device of the present invention. 
         FIG. 8B  is an enlarged partial end view of the embodiment of  FIG. 8A . 
         FIG. 8C  is an enlarged partial view of a clip leg of the embodiment of  FIG. 8A . 
         FIG. 8D  is an enlarged partial view of a clip locking mechanism of the embodiment of  FIG. 8A . 
         FIG. 8E  is an enlarged partial view of a clip locking mechanism and clip legs of the embodiment of  FIG. 8A . 
         FIG. 8F  shows enlarged partial side views of various embodiments of clip leg shapes available for use in the medical device of the present invention. 
         FIG. 8G  shows enlarged partial end views of various embodiments of clip leg shapes available for use in the medical device of the present invention. 
         FIG. 9A  is an enlarged partial view of the distal end of another embodiment of the medical device of the present invention. 
         FIG. 9B  is an enlarged partial view of the embodiment of  FIG. 9A  being deployed. 
         FIG. 10A  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 10B  is an enlarged partial view of the embodiment of  FIG. 10A  being deployed. 
         FIG. 11  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 12A  is an enlarged partial view of another embodiment of the medical device of the present invention showing the clip in an open position. 
         FIG. 12B  is an enlarged partial view of the embodiment of  FIG. 12A  showing the clip in a closed position. 
         FIG. 13A  is an enlarged partial view of another embodiment of the medical device of the present invention showing the clip in a closed position prior to disconnecting the clip. 
         FIG. 13B  is an enlarged partial view of the distal end of the embodiment of  FIG. 13A  showing the clip in a closed position after disconnecting the clip. 
         FIG. 13C  is an enlarged partial view of the embodiment of  FIG. 13A  showing the clip in a closed position after disconnecting the clip. 
         FIG. 14A  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 14B  is an enlarged partial side view of the embodiment of  FIG. 14A . 
         FIG. 14C  is an enlarged partial view of the distal end of the medical device of the embodiment of  FIG. 14A  after the clip has been released. 
         FIG. 15A  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 15B  is an enlarged partial view of the clip of the embodiment of  FIG. 15A  in a closed position. 
         FIG. 15C  is an enlarged partial view of the clip of the embodiment of  FIG. 15A  in an open position. 
         FIG. 15D  is an enlarged partial view of the distal end of the medical device of the embodiment of  FIG. 15A  after the clip has been released. 
         FIG. 16A  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 16B  is an enlarged partial close-up side view of the end of a clip leg of the embodiment of  FIG. 16A . 
         FIG. 16C  is an enlarged partial close-up edge view of the end of a clip leg of the embodiment of  FIG. 16A . 
         FIG. 16D  is an enlarged partial view of the embodiment of  FIG. 16A  with the clip in an open position. 
         FIG. 16E  is an enlarged partial view of the embodiment of  FIG. 16A  with the clip in a closed position. 
         FIG. 17A  is an enlarged partial view of another embodiment of the medical device of the present invention. 
         FIG. 17B  is an enlarged partial view of the embodiment of  FIG. 17A , showing the clip in an open position. 
         FIG. 18A  is an enlarged view of clip legs of another embodiment of the medical device of the present invention. 
         FIG. 18B  is an enlarged partial view of an embodiment of the medical device of the present invention using the clip legs of  FIG. 18A . 
         FIG. 18C  is an enlarged partial view of the embodiment of  FIG. 18B , showing the clip in a closed position. 
         FIG. 18D  is an enlarged edge view of the clip of the embodiment of  FIG. 18B . 
         FIG. 18E  is an enlarged partial end view of the embodiment of  FIG. 18B . 
         FIG. 18F  is an enlarged partial side view of the embodiment of  FIG. 18B . 
         FIG. 19A  is an enlarged partial edge view of another embodiment of the medical device of the present invention. 
         FIG. 19B  is an enlarged partial side view of the embodiment of  FIG. 19A . 
         FIG. 19C  is an enlarged partial view of a clip leg of the embodiment of  FIG. 19A . 
         FIG. 20A  is an enlarged partial end view of another embodiment of the medical device of the present invention. 
         FIG. 20B  is an enlarged partial side view of the embodiment of  FIG. 20A . 
         FIG. 20C  is a side-by-side comparison of two parts of the embodiment of  FIG. 20A . 
         FIG. 21  is an enlarged partial view of the distal end of another embodiment of the medical device of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     In a first embodiment of the invention as shown in  FIG. 1 , medical device  100  includes a clip  101  having first clip leg  102  and second clip leg  103 . Clip leg  102  has at least one lock hole  104  therein of any suitable shape (e.g. circular, rectangular, square, etc.). Likewise, clip leg  103  has at least one lock hole  105  therein of any suitable shape. Clip  101  is further characterized by a cut-out  106  on the proximal end. J-hook  107  is inserted into cut-out  106 . J-hook  107  is formed on the distal terminal end of control wire  108 . A retainer release  109  is formed by bends in the control wire  108 , the bends formed proximally from the j-hook  107 . The control wire  108  is enclosed within sheath  111  proximally from the retainer release  109 . Retainer  110  is coupled to control wire  108  and engages lock sleeve  113 . Retainer release  109  acts to disengage retainer  110  from lock sleeve  113  when a tensile force applied to control wire  108  is sufficient to cause such disengagement. An outer sleeve  112  is connected on the distal side of sheath  111 , and lock sleeve  113  is connected to a distal side of outer sleeve  112 . Lock sleeve  113  incorporates lock pawl  114 , which engages lock hole  104  in clip leg  102 , and lock pawl  115 , which engages lock hole  105  in clip leg  103 . 
     The clip  101  is a deformable, multi-legged, grasping device attached to the distal portion of a flexible shaft (the sheath  111 ) via a frangible link (the j-hook  107 ). The flexible shaft is connected at its proximal end to a handle ( FIG. 7 ), the handle analogous to biopsy forceps. A semi-rigid wire (the control wire  108 ), which is routed from the handle to the clip  101 , acts as a means of actuating the clip  101  between the open and closed position. The clip  101  can be actuated between the open and closed position multiple times as long as the lock holes  104  and  105  do not become engaged with the lock pawls  114  and  115  in the lock sleeve  113 . Once the operator decides the clip  101  should be permanently deployed, the handle can be fully actuated, which causes the retainer release  109  to pull the retainer  110  free from the outer sleeve  112  and lock sleeve  113 . After the retainer  110  is released, increasing force will begin straightening the j-hook  107 . The j-hook  107  is then pulled from the cut-out  106  on the proximal side of clip  101 . At this point, the retainer  110  and control wire  108  are no longer attached to the distal portion of the device (the clip  101  and lock sleeve  113 ) and the delivery device (e.g. an endoscope, not shown) can be removed while leaving the clip  101  (with lock sleeve  113 ) in place. 
     The sheath  111  serves three key functions in this embodiment. In its primary function it acts as a housing for the control wire  108 . In this function the sheath  111  supplies a resistive, compressive force opposite the tensile force applied to the control wire  108 , via the handle, as the lever ( FIG. 7 ) in the handle is moved to close the clip  101 . The forces reverse when the lever is moved in the opposite direction, and the control wire  108  is compressed to push the clip  101  forward. In this function, the combination of control wire  108  and sheath  111  act as a simple push-pull, cable actuation mechanism. 
     In the secondary function of sheath  111 , it acts as a means by which the clip  101  can be easily rotated. Ideally this rotation would be of a ratio of 1:1. In other words, one complete rotation of the sheath  111  at the proximal end would translate to one complete rotation of the clip  101 . This rotation however, depends on several factors. The relationship of the outside diameter of sheath  111  to the inside diameter of the working channel (not shown) of the endoscope (not shown), is one factor. Another factor is the amount of friction between the sheath  111  and the working channel caused by the path of the endoscope in the anatomy. Because these factors vary from endoscope to endoscope, and patient to patient, the rotation ratio will not always be the same. This ease of rotation is a key function and benefit of this embodiment in that it allows relatively precise orientation of the clip  101  to the vessel. Depending on the exact construction of the sheath  111 , and the other factors just listed, rotation of the device may be different in one direction of rotation versus the other direction. By taking advantage of the mechanical properties of the sheath  111 , this embodiment accomplishes rotation without the need for additional handle components. Eliminating the need for such components will: reduce the overall cost of the device; simplify how the device is operated; and make rotation more repeatable. In turn, all of these benefits will make for a faster procedure with a higher success rate. 
     The sheath  111  accomplishes a high rotation ratio by using a spiral wound, multiple-wire, stainless steel, flexible shaft, with an outside diameter of slightly less than the inside diameter of the working channel of the endoscope. Because the sheath  111  is made of a multiple-wire configuration, it is soft and bendable, yet rigid in rotation. In other words, the sheath  111  is flexible enough to be manipulated through a flexible endoscope, but has a very low angle of twist about its central axis. 
     In the third function of the sheath  111 , it acts as a component of the mechanism by which the clip  101  is released. The outer sleeve  112 , which is rigidly attached to the sheath  111  by methods known in the prior art (e.g. adhesives, welding, swaging, etc.), is made of a rigid tube, with two retainer cut-outs (not shown), situated 180° apart from each other. These retainer cut-outs house the two tabs  118 ,  119  ( FIG. 6 ) of the retainer  110 . As the control wire  108  is actuated, drawing the clip  101  back into the lock sleeve  113 , the retainer release  109  forces the retainer  110  to be disengaged from the outer sleeve  112 . 
       FIG. 2  shows the clip  101  in the closed position but prior to release of the j-hook  107 . In the closed, locked position shown in  FIG. 2 , lock hole  104  of clip leg  102  is engaged by lock pawl  114 , and lock hole  105  of clip leg  103  is engaged by lock pawl  115 . The fit between the lock sleeve  113  and outer sleeve  112  is such that the lock sleeve  113  (and therefore the clip  101 ) will easily release from the outer sleeve  112  once the j-hook  107  has been straightened and the retainer disengaged from the outer sleeve  112 . 
     The clip  101 , shown in  FIG. 3 , is manufactured of a single piece of stainless steel, or any suitable biocompatible material, and is bent into a two-legged geometry. The clip legs  102  and  103  have a rectangular cross section of approximately 0.06 inches by 0.01 inches and are approximately 0.50 inches in length. The profile of the legs serves three purposes: first; the distal portion grasps the tissue during the procedure; second, the distal portion acts as the compression mechanism to hold the clip in place after deployment; and third, the profile between the distal grasping portion and the proximal end will interface with the lock pawls (not shown), via lock hole  104  in clip leg  102  and lock hole  105  in clip leg  103 . The interface between the lock holes and the lock pawls creates the mechanical lock that will keep the clip  101  closed after deployment. The proximal end of the clip  101  is formed with a cut-out  106  into which the j-hook ( FIG. 2 ) is attached. 
     The lock sleeve  113  shown in  FIG. 4  consists of a tubular proximal section, which fits into the distal end of the outer sleeve  112 . Retainer hole  116  and opposite retainer hole (not shown) in the lock sleeve  113  receive the retainer tabs  118 ,  119  ( FIG. 6 ). The distal end of the lock sleeve  113  has a lock sleeve cut-out  117  slightly larger than the cross section of the clip legs ( FIG. 3 ). As the clip leg are pulled through cut-out  117 , the clip legs are compressed toward each other, thus compressing the tissue (not shown) situated between the clip legs. The cut-out  117  has lock pawls  114  and  115 , which align with the two lock holes ( FIG. 3 ) in the clip legs. After the desired tissue purchase has been acquired, the clip can be pulled back far enough to engage the lock pawls  114  and  115  into the two lock holes. 
     Forming the end of the control wire  108  into a j-hook  107  makes a frangible link shown in  FIG. 5 . This relatively simple configuration eliminates extraneous components that take up space and complicate the assembly. The control wire  108  is bent such that it wraps around the proximal end of the clip ( FIG. 3 ), through a cut-out ( FIG. 3 ). Another bend in the wire, proximal to the j-hook  107 , acts as a retainer release  109 . The retainer release  109  operates to release the retainer  110  ( FIG. 6 ) from the lock sleeve  113  ( FIG. 4 ). As the control wire  108  is actuated and the clip is locked into the lock sleeve, the retainer release  109  pulls the retainer  110  back, disengaging the retainer tabs  118 ,  119  from the two retainer holes  116  ( FIG. 4 ) in which the retainer normally resides. After this disengagement is complete, the j-hook  107  is then straightened by force, in turn releasing the clip. The j-hook  107  is able to deform to a straightened position (i.e. release) at a predetermined tensile load, which is slightly greater than the load required to grasp the tissue (not shown), compress the tissue, and engage the lock pawls ( FIG. 4 ) in the lock holes ( FIG. 3 ). 
     The control wire  108  shown in  FIG. 6  is a simple stainless steel wire used to actuate the clip  101  via a handle ( FIG. 7 ), at the proximal end of the sheath ( FIG. 1 ). In this embodiment of the invention, the frangible link (the j-hook  107 ) is formed in the distal end of the control wire  108  as a one-piece design. The proximal end of the control wire  108  is terminated inside the handle. The control wire  108  also has the retainer release  109  formed in it, behind the j-hook  107 . The retainer release  109  causes the outer sleeve ( FIG. 1 ) to disengage from the retainer  110 . This is done sequentially, after the lock holes ( FIG. 3 ) in the clip  101  have engaged the lock sleeve ( FIG. 4 ). After the lock holes engage the lock sleeve, tensile force applied to control wire  108  first straightens j-hook  107  so that j-hook  107  releases from cut-out  106 , then retainer release  109  engages and deforms retainer  110  so that retainer tabs  118  and  119  disengage from the outer sleeve ( FIG. 1 ) and the lock sleeve ( FIG. 4 ). Alternatively, retainer release  109  could engage and deform retainer  110  before j-hook  106  straightens and disengages from cut-out  106 . 
     The handle shown in  FIG. 7  is attached to the proximal end of the sheath  111  at a sheath-handle attachment point  120 . The handle configuration is unlike a handle found on conventional endoscopic forceps known in the prior art. The handle provides a mechanism by which the amount of linear actuation required in the handle body  121  is greater than that which is translated to the tip of the device ( FIG. 1 ). In other words, actuation of the activator or handle lever  122  of 1.00 inch in turn may only move the clip ( FIG. 3 ) by 0.10 inch. This feature allows for a more tactile feel when placing the clip on the vessel (not shown). In effect, very subtle amounts of movement in the clip can be accomplished by more exaggerated, less precise movements of the operator&#39;s hand. This is accomplished because the activator or lever  122  pivots about a pivot point  123  that is close to the attachment point  124  of the control wire  125 . 
     An alternative embodiment of the device may be made up of clips with more than two legs.  FIGS. 8A through 8E  show a clip with four legs.  FIG. 8A  shows a view from the side, showing clip legs  801 . This embodiment could be actuated and released in the same way the previous embodiment is activated and released, through a clip locking mechanism  802 . The use of a control wire (not shown) would actuate the multiple-legged clip in and out of an outer sleeve  803  until such time that the operator desires to release the clip. Alternatively, actuation of the control wire might move the outer sleeve  803  in and out over the multiple-legged clip to open and close the clip legs  801 , until such time that the operator desires to release the clip.  FIG. 8B  shows the four-legged clip of  FIG. 8A  from the perspective of the targeted tissue looking proximally. The four clip legs  801  are shown in an open position and are situated at 90° from each other.  FIG. 8C  shows a profile view of a single clip leg  801 .  FIG. 8D  shows a view along the axis of clip locking mechanism  802 .  FIG. 8E  shows another view of a four-legged clip with clip legs  801  and clip locking mechanism  802 . 
       FIG. 8F  shows alternative side profiles of the clip geometry. Use of such geometries in a clip with two or more legs allows for improved grasping ability in different situations. Given the large variation in tissue thickness and tissue strength, it is likely that different clip profiles would excel in different procedures.  FIG. 8G  shows alternative end profiles of the clip geometry. As with the varying side profiles, different end profiles would provide a broader range of grasping capabilities. 
       FIGS. 9A and 9B  illustrate an alternative embodiment of the device using a different method to lock the clip in the closed position. This alternative method uses an expanded coil spring  901  released over the outside of the clip legs  904  and  905  to lock the clip legs  904  and  905  closed.  FIG. 9A  shows this embodiment in a predeployment state.  FIG. 9A  shows a stretched coil spring  901 , twisted to a diameter larger than that of the relaxed state of coil spring  901 . Stretched coil spring  901  is placed over a rigid tube  903  at the distal end of the clip device. Within this rigid tube  903 , the clip legs  904  and  905  are free to move in and out (in a manner similar to the manner described for the previous embodiments), between the opened and closed position via a control wire (not shown). When the desired clip location has been achieved, the sheath  902  is used to push the coil spring  901  off of the rigid tube  903 , onto the clip legs  904  and  905 , as shown in  FIG. 9B . The inward radial forces present in the recovered coil spring  901  act to keep the clip legs  904  and  905  compressed. 
       FIGS. 10A and 10B  illustrate another alternative embodiment. In this embodiment, a flexible linkage  1002  and pill  1003  are used to lock the clip legs  1001 . In this embodiment the clip legs  1001  are actuated via a control wire  1006 , as described in previous embodiments. However, in this embodiment, the clip legs are not closed by pulling the clip legs  1001  through some feature smaller than the open clip. Instead the clip legs  1001  are closed by drawing the two flexible links  1002  proximally, in the direction of the control wire  1006 , while a compressive force is applied to the base of the clip legs  1001  by a rigid sheath (not shown). This in turn pulls the legs of the clip toward each other.  FIG. 10A  shows the clip legs  1001  in an open position.  FIG. 10B  shows the clip legs in a closed position. The clip legs  1001  are locked in a closed position when the pill  1003 , located at the center of the flexible linkage  1002 , is drawn through a one way hole  1004  in the center of the clip legs  1001 . The one way hole  1004  is tapered, with a diameter slightly larger than the diameter of the pill  1003  on its distal side and a diameter smaller than the diameter of the pill  1003  on its proximal side. The pill stretches the material around the hole  1004  as it passes through moving proximally. Alternatively, the pill  1003  itself can be made of an elastic material and would deform slightly while passing proximally through hole  1004 . This funneling effect of the pill  1003  through the hole  1004  only allows the pill  1003  to easily pass through in the locking direction. This locking action is maintained after the clip is released by positioning the frangible link  1005  in a proximal direction on control wire  1006  from the pill  1003 , thus maintaining tissue compression. In this embodiment the frangible link  1005  is a taper in control wire  1006 , enabling the link to be broken at a specific position (proximal from the pill  1003 ) with a predetermined tensile load. 
     One alternative to the j-hook type frangible link previously described is shown in  FIG. 11 . This embodiment uses a threaded fitting that is a combination of a male thread  1103  and a female hub  1102  to attach the control wire (not shown) to the clip  1001 . The clip  1001  can be actuated from the opened position (not shown) to the closed position (shown) as described in previous embodiments. In this embodiment, the lock sleeve  1105  is shorter and engages dimples  1106 . After the lesion (not shown) is properly targeted, the clip  1101  can be released. The clip  1101  is released when a predetermined tensile load is applied to the male thread  1103 , in a similar fashion to the predetermined tensile load applied to straighten the j-hook. This force causes the male thread  1103  to detach from the female hub  1102 . The female hub  1102  may be constructed of a spiral wound wire component with a pitch equal to the thread pitch formed to make the male thread  1103 . The fit of the threaded components is such that the predetermined force will overcome the engaged threads of the male thread  1103  and the female hub  1102 , causing them to separate, or “strip” away from one another. 
     Another alternative to the j-hook type frangible link is shown in  FIGS. 12A and 12B . This embodiment uses a ball  1202  fitting into a socket, where the socket is defined by socket tabs  1203 , to attach the control wire  1207  to the clip  1201 . An outer sleeve  1204  is attached by way of a breakaway connection (not shown) to the sheath  1206 . This breakaway connection may be a light interference fit, or a light adhesive joint. The breakaway connection must be weak enough that when the sheath  1206  is pulled back through the working channel (not shown) of the endoscope (not shown), the outer sleeve  1204  will release with the clip  1201 . The clip  1201  is released when the socket tabs  1203  at the proximal end of the clip  1201  are aligned with cut-outs  1205  in the outer sleeve  1204 . These cut-outs  1205  act as a relief area into which the socket tabs  1203  can be deformed when a predetermined tensile load is applied to them via the ball  1202  formed on the end of the control wire  1207 . The outer sleeve  1204  is released with clip  1201  so that the clip  1201  remains locked after deployment. 
     Another alternative to the j-hook type frangible link is shown in  FIGS. 13A ,  13 B and  13 C. All the figures show the clip  1301  in a closed and locked state.  FIG. 13A  shows the clip  1301  in a closed position but before it is released and shows a portion of outer sleeve  1303  cut away to show the internal workings of the clip mechanism.  FIGS. 13B and 13C  show the clip  1301  after being released. In this embodiment, the actuation is still performed via a control wire  1304 , however the direction of action is reversed. As the control wire  1304  is pushed forward, the clip  1301  is closed by the advancement of outer sleeve  1303  and lock ring  1302  over the clip legs. The locking sleeve  1302  and clip geometry, including dimples  1306 , is the same as that explained in the embodiment of  FIG. 11 . 
     A difference between the embodiment shown in  FIGS. 13A ,  13 B and  13 C and the prior embodiments is the mechanism by which the clip  1301  is released from the rest of the device. An interference fit between the outer sleeve  1303 , sheath  1305 , and male threaded hub  1308  is created when the device is assembled. The distal end of the sheath  1305 , in its manufactured (but unassembled) state, has an outside diameter greater than the inside diameter of the outer sleeve  1303 . When the outer sleeve  1303  and sheath  1305  are assembled together part of the interference fit is created. The distal end of the sheath  1305 , again in its manufactured (unassembled) state, has an inside diameter greater than the diameter of the male threaded hub  1308 . During assembly, as the distal end of the sheath  1305  is compressed to fit inside the outer sleeve  1303 , it is compressed down onto the male threaded hub  1308  to create a sandwich of the sheath  1305  between the male threaded hub  1308  on the inside and the outer sleeve  1303  on the outside. During the medical procedure, at the time the operator wishes to release the clip  1301 , this interference fit is overcome. The interference fit is overcome by advancing the outer sleeve  1303  so far forward, by creating a compressive force in the control wire  1304  in opposition to a tensile force on the sheath  1305 , that the outer sleeve  1303  is no longer in contact with the distal end of the sheath  1305 . 
     The outer sleeve  1303  and the control wire  1304  serve two purposes in this embodiment. The outer sleeve  1303  and the control wire  1304  supply the closing force to the clip  1301 . In  FIGS. 13A ,  13 B, and  13 C, a lock ring  1302  is used to maintain the closing force on the clip legs  1307 . The outer sleeve  1303  and the control wire  1304  also act as key components of the release mechanism. As previously described, once the outer sleeve  1303  is moved to its forward-most position, the end of the sheath  1305  is no longer contained within the outer sleeve  1303 , and is free to separate from the male threaded hub  1308 . The sheath  1305  is free to release because of the manner in which the distal end of the sheath  1305  is manufactured/assembled. 
     When the outer sleeve  1303  is advanced forward, allowing the distal end of the sheath  1305  to be free, the distal end of the sheath  1305  expands to its original, manufactured state. This allows the inside of the sheath  1305  to release from the male threaded hub  1308 . The male threaded hub  1308 , and thus the clip  1301 , are now free from the sheath  1305  and the rest of the delivery device. As shown in  FIG. 13C , the outer sleeve  1303  remains connected to the control wire  1304  at connection point  1310 , and both can be removed with the sheath  1305 . The distal portion of control wire  1304  is bent towards, and connects with, outer sleeve  1303  at connection point  1310 . The distal portion of control wire  1304  passes male threaded hub  1308  during deployment through slot  1309  in male threaded hub  1308 . 
       FIGS. 14A ,  14 B, and  14 C show an alternative embodiment of the present invention. In the embodiment of  FIGS. 14A ,  14 B, and  14 C, the relaxed state of the clip is closed, and it is forced open and allowed to close naturally.  FIG. 14A  shows a side view of the clip  1401  in a closed, pre-released state, and  FIG. 14B  shows an edge view of the clip  1401  in a closed, pre-released state. In this embodiment, because the clip  1401  is manufactured such that the clip legs  1407  are naturally closed, the primary function of the control wire  1406  is changed from having to close the clip  1401 , to having to open the clip  1401 . The clip  1401  is manufactured in a generally x-shaped geometry, where each tab  1403  at the proximal end of the clip  1401  controls a clip leg  1407  opposite at the distal end of the clip  1401 . The action/reaction of the clip  1401  is similar to that of a common clothes pin. As the tabs  1403  are brought together, the clip legs  1407  are spread apart. As the tabs  1403  are released, the clip legs  1407  come together. A u-ring  1402  attached to the end of the control wire  1406  is used to bring the tabs  1403  together, thus opening the clip  1401 . Pulling on the control wire  1406  pulls the u-ring  1402  into contact with tabs  1403  creating a compressive force to open clip legs  1407  because clip  1401  is positioned against fulcrum point  1408 . Advancing control wire  1406  advances u-ring  1402 , thereby removing the compressive force on tabs  1403  and allowing clip legs  1407  to close. Advancing control wire  1406  further to a deployment position pushes u-ring  1402  against clip legs  1407 , causing clip  1401  to move out of outer sleeve  1404  into a deployed state. 
     The control wire  1406  is constructed of material having a shape memory, and the distal end of the control wire  1406 , where the u-ring  1402  is attached, is pre-bent to one side. While a minimum tension exists in control wire  1406 , the u-ring remains around the constriction. However, when the desired location for the clip  1401  has been achieved, and the clip tabs  1403  have been advanced beyond outer sleeve  1404 , the control wire  1406  can be advanced to its most distal position. Because the control wire  1406  is pre-bent, as it is advanced the u-ring  1402  becomes disengaged from the clip  1401  when the tension in control wire  1406  falls below a predetermined amount, as shown in  FIG. 14C . This allows the clip  1401  to be released. 
       FIGS. 15A ,  15 B,  15 C, and  15 D show another embodiment in which the clip is manufactured in a naturally closed position.  FIG. 15A  shows the distal end of medical device  1509  with the clip  1501  in a closed position before deployment.  FIG. 15B  shows only the clip  1501  in a closed position.  FIG. 15C  shows the clip  1501  in an open position.  FIG. 15D  shows the device after the clip is released. The clip  1501  is shaped such that, as the control wire  1503  is pulled in a proximal direction, the clip legs  1508  are forced apart from one another. This is accomplished using a pill  1502  attached to the end of the control wire  1503  as explained in previous embodiments. Two rigid arms  1504 , located between the clip legs  1508 , translate the tensile force on the control wire  1503  to an outward radial force on the clip legs  1508 . When the desired location for the clip  1501  has been achieved, the control wire  1503  can be advanced to its most distal position. Because the control wire  1503  is constructed of material that has a shape memory, and because the control wire  1503  is pre-bent close to the pill  1502 , as the control wire  1503  is advanced, the pill  1502  becomes disengaged from the pill well  1507 . When the pill  1502  moves out and away from the pill well  1507 , the clip  1501  is released and disengages from the control wire  1502 , the sheath  1506 , and the outer sleeve  1505 . 
       FIGS. 16A ,  16 B,  16 C,  16 D, and  16 E show another embodiment in which the clip is manufactured in a naturally closed position.  FIG. 16A  shows the clip  1607  in a closed, predeployed, state.  FIG. 16B  shows a side view of one clip leg  1601  with the pill  1603  still resting in pill well  1604 .  FIG. 16C  shows an edge view of one clip leg  1601  with the pill  1603  still resting in pill well  1604 .  FIG. 16D  shows a clip  1607  in an open position.  FIG. 16E  shows a clip  1607  in a closed position. This embodiment uses two control wires  1605 . Alternatively, a branched control wire may be used. By using a branched control wire or two control wires  1605 , the force can be transmitted to a point further away from the fulcrum (bending point)  1606  of the clip  1607 . The greater this distance, the lesser the force required to open the clip legs  1601 . As in the previous embodiments, the control wires  1605  are disengaged from the clip  1607  by pushing them forward. This action disengages the pills  1603  from the clip  1607  by moving the pills  1603  out of pill wells  1604 . The control wires  1605  are made from a material with a shape memory, so that when freed from pill wells  1604 , the pills  1603  move away from the pill wells  1604 , and the clip  1607  is deployed. 
     Another embodiment is shown in  FIGS. 17A and 17B . In this embodiment, the control wire or wires  1701  are routed to gain mechanical advantage. In this embodiment, the clip  1702  is naturally closed, with the control wire(s)  1701  routed to leverage points  1704  further away from the fulcrum (bending point)  1705  of the clip  1702 . In this embodiment, the control wire(s)  1701  are looped around pins positioned at leverage points  1704  at the ends of the clip legs  1706 . The control wire(s)  1701  are then routed to a point at the proximal end of the clip. The control wire(s)  1701  are then terminated at this point. For ease of manufacture, the control wire(s)  1701  could essentially be one, continuous wire, with both ends terminated in the handle (not shown). To release the clip  1702 , one end of control wire  1701  could be detached from the handle and pulled free from the clip  1702 . Because the control wire  1701  is only wrapped around pins positioned at leverage points  1704  on the clip  1702 , by pulling on one end of control wire  1701 , control wire  1701  could be easily detached when the desired location for clip  1702  has been achieved by continuing to pull on one end of control wire  1701  until all of control wire  1701  has been detached from the clip  1702 . 
       FIGS. 18A ,  18 B,  18 C,  18 D,  18 E, and  18 F show an embodiment of a clip which incorporates the natural compressive forces present in a simple elastic band (or o-ring)  1802  to hold the clip legs  1801  in the closed position.  FIG. 18A  shows two clip legs  1801  in a disassembled state.  FIG. 18B  shows a clip with the control wire  1803  engaging a second elastic band  1804  to open clip legs  1801 . In this embodiment, the control wire  1803  is attached to the proximal end of the clip legs  1801  via a frangible link. In this embodiment, the frangible link is a second elastic band (or o-ring)  1804  that will deform as the control wire  1803  is pulled back. In this embodiment, the clip is housed in the end of a sheath  1806  such that, as the control wire  1803  is pulled back, the second elastic band  1804  delivers an increasing compressive force to the clip legs  1801  proximal to a pin joint  1805 , thereby causing the clip legs  1801  distal from the pin joint to open against the compressive force of elastic band  1802 . In this manner, the clip legs  1801  move to an open position, as shown in  FIG. 18B .  FIG. 18C  shows the clip in a closed, predeployed state.  FIG. 18D  shows a profile view of clip legs  1801 , and  FIG. 18E  shows an end-on view of clip legs  1801  within sheath  1806 .  FIG. 18F  shows a close-up view of clip legs  1801  without first elastic band  1802  but showing band slots  1809 .  FIG. 18F  shows second elastic band  1804  resting over nubs  1807  and coupled to control wire  1803 . When the desired clip location has been achieved, the second elastic band  1804 , which makes up the frangible link, is overcome by pulling the control wire  1803  to its most proximal position. This has the effect of breaking second elastic band  1804 . Alternatively, second elastic band  1804  could be designed to release over nubs  1807 . In a third alternative, after placing clip legs  1801  in the desired location, control wire  1803  can be released so that elastic band  1802  again closes clip legs  1801 . In this third embodiment, control wire  1803  is made of a suitable material, such as a shape memory material, and has a bend in the distal region such that moving control wire  1803  to a maximum distal position acts to unhook hook  1808  from second elastic band  1804 . 
       FIGS. 19A ,  19 B, and  19 C show another embodiment of the invention utilizing a naturally closed clip. Clip  1901  is held in the naturally closed position by a torsion spring  1903 . The clip  1901  is actuated from the closed to the opened position in a different way than prior embodiments. A plunger  1904 , located within the outer sleeve  1905  at the end of the sheath (not shown), is used to push on the tabs  1906  on the proximal end of the clip  1901 . The tabs  1906  are pushed through an opening  1907  in the end of the outer sleeve  1905 . This moves tabs  1906  close together, in turn moving the clip legs  1902  to the open position. When the desired clip location has been achieved, the clip  1901  can be released by advancing the plunger  1904  to its most distal position.  FIG. 19B  shows the clip  1901  from a profile view.  FIG. 19C  shows a single clip leg  1902  and connection point  1908  for pivotally connecting clip legs  1902  to each other. 
       FIGS. 20A ,  20 B, and  20 C describe the embodiment of a three-legged clip and delivery device. The clip  2001  is manufactured to be in the naturally open position. The clip  2001  is characterized by male threads  2002  on its outer surface. The delivery device consists of a sheath  2003  similar to those described in previous embodiments. An inner sleeve  2004  located within the distal end of the sheath  2003  is used to actuate the clip  2001  from its naturally open position to the closed position. The inner sleeve  2004  has female threads (not shown) on its inside diameter. A control wire (not shown) is used in this device to transmit rotational force rather than tensile/compressive force. Rotating the sheath  2003  with respect to the control wire, with the handle (not shown) actuates the clip  2001 . This rotation force is translated to the female threads, causing them to be threaded onto the clip  2001 . As the naturally open clip legs  2005  move toward the inner sleeve  2004 , the clip legs  2005  are closed. The clip  2001  and inner sleeve  2004  are released from the sheath  2003  via some form of frangible link (not shown) as described in the previous embodiments.  FIG. 20A  shows the clip legs  2005  and inner sleeve  2004  from the perspective of the target area.  FIG. 20C  shows the size relationship between the female threads on the inner sleeve  2004  and the male threads  2002  on the clip  2001 . 
       FIG. 21  shows another embodiment of a naturally open clip and delivery device.  FIG. 21  shows the distal portion of the medical device with a portion of the outer sleeve  2102  cut away to show the inner mechanics of the clipping device. The delivery device consists of a sheath  2103  similar to those described in previous embodiments. The clip  2101  is actuated from the open to the closed position via a control wire  2104 , as described in the primary embodiment. A frangible link is implemented in this embodiment by a breakable link  2105 . In this embodiment the lock sleeve is eliminated. Eliminating the lock sleeve reduces the number of components and the overall size of the device. In this embodiment the outer sleeve  2102  is used to hold the clip  2101  in the closed position. Therefore, the outer sleeve  2102  must be deployed from the sheath  2103  when the clip  2101  is released. To create a positive mechanical lock between the clip  2101  and outer sleeve  2102 , the clip  2101  has two deformable tabs  2106  formed in its proximal end. When the desired tissue purchase has been accomplished, the control wire  2104  is further actuated by the handle (not shown) so that the tabs  2106  reach a position where they are in the same plane as the cut-outs  2107  in the outer sleeve  2102 . Once the tabs  2106  have reached this point, further actuation of the control wire  2104  forces the tabs  2106  to deform through the cut-outs  2107  in the outer sleeve  2102 . As in the first embodiment, a retainer  2108  is used to create a mechanical lock between the sheath  2103  and outer sleeve  2102 . In this embodiment the retainer  2108  passes through slots  2109  in the outer sleeve  2102  and a sheath connector  2110 . The sheath connector  2110  is simply a rigid connector, applied to the end of the sheath  2103  by some means known in the art (e.g. welding, adhesive, swaging, etc.). As the tabs  2106  become engaged, a tensile load in the control wire  2104  is translated to the breakable link  2105 . At a predetermined tensile load, the breakable link  2105  breaks. As the control wire  2104  is further actuated, a distal portion of control wire  2104 , which is preformed into a shape that will function as a retainer release, engages the retainer  2108 . The retainer  2108  is pulled from the outer sleeve  2102  by the control wire  2104 , in a similar manner to that described in the primary embodiment. Once this is done, the sheath connector  2110  (and therefore the sheath  2103 ) is released from the outer sleeve  2102 . 
     The materials utilized in construction of the clip of the present invention include many bio-compatible materials (metals, polymers, composites, etc.). A stainless steel grade material, which offers good spring properties, may be used. The clip can also be coated, or plated, with a material like gold to improve radiopacity. 
     The lock sleeve, lock pawls, retainer and outer sleeve may be comprised of any of the same materials as the clip component. For example, stainless steel may be used. 
     The control wire in the first embodiment may be a stainless steel wire. Because the wire must offer sufficient strength in both tension and compression, the material properties of the wire are important to the functionality of the device. Also, the end of the wire, where the j-hook is formed, must deform when a predetermined tensile load is applied. The device&#39;s ability to release the clip is dependent on this property. Other embodiments of the device may incorporate a two (or more) piece wire so that certain sections of the wire have different material properties or geometries. Different material properties or geometries could allow for more control over how and when the wire detaches from the distal tip of the device. This could also be accomplished by several other methods, as well. For example, localized heat treating and/or coatings could be used along portions of the wire to alter the material characteristics. Additionally, some embodiments of the present invention require a control wire constructed of a material with a shape memory. 
     The sheath, in the first embodiment, is made up of several round, stainless steel wires, wound in a helical pattern to create a hollow, semi-rigid shaft. Sheaths made in this fashion are well known in the prior art. In other embodiments, the sheath could be made up of non-round wires. Other embodiments may be made up of one or more wires formed in a pattern other than a single helix, as in the first embodiment. A multiple helix or braided pattern may be used. The sheath may also be coated with a protective coating of Polytetrafluoroethylene (PTFE), or similar materials. The use of such coatings could be used to alter the flexibility of the shaft. Such coatings could also be used to increase the lubricity (decrease the coefficient of friction) between the endoscope working channel and the device. Similar materials could also be used to encapsulate the sheath&#39;s base material. This would create a matrix material, providing a combination of material properties not feasible with one single material. Other embodiments may use materials other than stainless steel as the base material. Materials such as titanium, nitinol, and/or nylon fibers may be incorporated. 
     A method of using the endoscopic hemostatic clipping device is provided. The method involves placing an endoscope in a body cavity as is known in the art. The device provided herein is then inserted through the endoscope. At the distal end, the endoscope is positioned near the target area. As noted above, the target area may be a lesion, a bleeding ulcer, a tumor, other abnormality, or any number of other tissues to be pinched, marked, tagged, or to which the operator wishes to apply a pinching pressure for whatever reason. The device provided is then positioned so that the clip legs embrace the target area, then the actuator is activated to close the clip legs. The success or failure of the application of pressure can be reviewed through the optical components provided separately in the endoscope. If the pinching is unsuccessful or only marginally successful, the clip legs of the device may be opened by reversing the actuation of the activator. Alternatively, if the pinching is successful, and the operator wishes to deploy the device, the actuator is fully activated, or the alternative deployment activator is activated. Finally, the remaining portion of the medical device and the endoscope are removed from the body. 
     It will be obvious to those skilled in the art, having regard to this disclosure, that other variations on this invention beyond those specifically exemplified here may be made. These variations include, but are not limited to, different combinations of clips, closing mechanisms, locking mechanisms, frangible links, and clip leg formations. Such variations are, however, to be considered as coming within the scope of this invention as limited solely by the following claims.