Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/257,654 filed on Nov. 3, 2009, entitled “PLANAR CLAMPS FOR ANASTOMOSIS,” the entire contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present embodiments relate generally to medical apparatuses for forming an anastomosis between two viscera, and more particularly relates to forming a side-to-side anastomosis such as a gastrojejunostomy. 
     BACKGROUND OF THE INVENTION 
     Historically, gastrointestinal (GI) surgery has been performed to create a channel between two viscera for the purpose of redirecting bodily fluids, i.e., an anastomosis. It will be recognized that there may be a need to anastomose many different viscera, such as the jejunum and the stomach (gastrojejunostomy), the bile duct and the duodenum, two sections of the small or large intestines, or various other combinations of viscera such as during bariatric surgery. 
     During surgery to form an anastomosis, the two tissues are often brought together and affixed to one another using fixators such as sutures, staples, or some other fixation means. While fixators are being placed, the tissues of the respective viscera are held in proximity to one another using various means. In open surgery, this is usually accomplished with graspers, forceps, or other tissue holding instruments manipulated by clinicians. In laparoscopic surgery, similar instruments may be used, except the laparotic access limits the number of instruments to a few percutaneous “ports,” making the technical challenge of the procedure much greater. 
     When these types of GI surgery are performed, there exists the potential to breach the mural boundary. Thus, extreme care must be taken to prevent contamination of the pleural and abdominal cavities with GI contents, which are laden with bacteria that do not naturally occur in those locations. If significant contamination occurs, then serious infection can set-in, which can lead to serious illness or death if not treated early and vigorously. 
     To address some of these limitations and to minimize the invasiveness of such surgeries, magnetic anastomosis devices (MADs) were developed for forming anastomosis. For example, a MAD may consist of two magnet cores surrounded by metal rims. The two magnet cores are positioned in the two viscera between which the anastomosis is desired. Due to the magnetic attraction between the cores, the walls of the two adjacent viscera are compressed. The compression of the walls of the viscera results in ischemic necrosis to produce an anastomosis between the two viscera. When using MADs, it is sometimes necessary to conduct a second procedure to insert a stent or other device to maintain the anastomosis that the MADs created. A second procedure requires additional costs, patient and physician time, and involves certain risks associated with any endoscopic procedure. Also when using MADs, the distal magnet must be placed in the intestine, usually the jejunum, which requires the use of an intestinal lumen. For patients with tumors or strictures, it may be difficult for an endoscope and/or the distal magnet to pass through. In addition, when using MADs an anastomosis is created over a several day period, rather than being created immediately at the time of the procedure. 
     SUMMARY OF THE PREFERRED EMBODIMENTS 
     The present embodiments provide medical apparatuses and a method for rapidly forming an anastomosis between two viscera while reducing the technical challenge and minimizing the potential risk of prior techniques for forming anastomoses. The anastomosis may be formed with surety before the patient leaves the medical facility and eliminates the need for a follow-up procedure. Additional protection against breach of the mural boundary is provided and there is minimal risk of the anastomosis becoming separated or forming a leak while the patient is not in the medical facility. 
     According to one embodiment, a medical apparatus for approximating the tissues of two viscera includes affixing to the end of an elongate member a medical device that includes two clamps, each clamp including an exterior clamp member and an interior clamp member, and then inserting the medical device through the bodily walls of two viscera. The interior clamp members define an interior space between them sized to permit formation of the anastomosis therebetween and to maintain the anastomosis, while the movable exterior and interior clamp members compress the two viscera and maintain them in close proximity. The medical device is held to the end of the elongate member and delivered via a tubular cap; alternatively, the elongate member itself holds the medical device and delivers it. Further, the medical device may be held on a separate elongate member, such as a catheter, that runs alongside the elongate member. 
     According to more detailed aspects of the medical device, the movable clamps each have an exterior clamp member and an interior clamp member that move between a delivery state and a deployed state, wherein the clamp members are biased toward the deployed state. In the deployed state, the exterior and interior clamp members are coplanar. In the delivery state, the exterior clamp members and the interior clamp members move away from each other, out of plane, so that the exterior clamp members are more proximate to each other and the two interior clamp members are more proximate to each other. 
     A method for forming an anastomosis between two viscera is also provided in accordance with the teachings of the present embodiments. Generally, two stomas are created in two viscera, the stomas are brought into proximity with each other, and then the medical device with the two clamps as described above is provided and inserted into the stomas. The medical device is positioned such that the exterior clamp members and the interior clamp members compress the walls of the two viscera between them and hold the walls proximate to each other. 
     According to more detailed aspects of the method, the size of the anastomosis may be immediately enlarged by using a knife or other cutting device to excise additional tissue from the walls of the two viscera located within the interior space defined by the interior clamp members. The excising step may be performed endoscopically, and the cutting instrument may be introduced through a working channel of an endoscope. 
     Other systems, methods, features and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be within the scope of the invention, and be encompassed by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views. 
         FIG. 1  is a perspective view of a preferred embodiment of a medical device in a deployed state for forming an anastomosis. 
         FIG. 2  is a perspective view of the medical device depicted in  FIG. 1  in a delivery state. 
         FIG. 3A  is a side view, partially in cross-section, of an apparatus for forming an anastomosis which includes the medical device of  FIG. 1  in the delivery state and a control wire to deploy the medical device. 
         FIG. 3B  is a side view, partially in cross-section, of an apparatus for forming an anastomosis which includes the medical device of  FIG. 1  in the delivery state and a tether to deploy the medical device. 
         FIG. 4  is a front view, partially in cross-section, of the apparatus of  FIG. 3A , with the medical device of  FIG. 1  partially deployed. 
         FIG. 5  is a front view, partially in cross-section, of the apparatus of  FIG. 3A , with the medical device of  FIG. 1  fully deployed. 
         FIG. 6  is a perspective view of another embodiment of a medical device in a delivery state for forming an anastomosis. 
         FIG. 7  is a front view of an apparatus for forming an anastomosis which includes the medical device of  FIG. 6  contained within one embodiment of a tubular cap. 
         FIG. 8  is a front view of the apparatus of  FIG. 7  with the medical device partially deployed. 
         FIG. 9  is a perspective view of another embodiment of a tubular cap with the medical device of  FIG. 6  contained within the tubular cap. 
         FIG. 10  is a perspective view of another embodiment of a medical device in a deployed state for forming an anastomosis. 
         FIG. 11  is a top view of the embodiment of  FIG. 1  deployed in tissue. 
         FIG. 12  is a top view of the embodiment of  FIG. 1  deployed in tissue where additional incisions have been made to enlarge the anastomosis. 
         FIG. 13  is a front view of an apparatus for forming an anastomosis which includes the medical device of  FIG. 10  in the delivery state. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the present application, the term “proximal” refers to a direction that is generally towards a physician during a medical procedure, while the term “distal” refers to a direction that is generally away from the medical professional and/or towards a target site within a patient&#39;s anatomy during a medical procedure. 
     Referring now to  FIGS. 1 to 2 , an embodiment of a medical device  20  is depicted for forming an anastomosis, such as during an endoscopic procedure. As will be discussed herein, the medical device  20  serves to clamp the tissue surrounding an anastomosis, hold it open, as well as facilitate enlargement of the anastomosis. The medical device  20  generally includes a first clamp  30  and a second clamp  40  defining a lateral axis  70  and a longitudinal axis  72 , positioned opposite each other along the lateral axis  70 , i.e., opposite each other relative to the longitudinal axis  72 . The first clamp  30  has a first exterior clamp member  32  and a first interior clamp member  34 . The first exterior and interior clamp members  32  and  34  connect to each other via intermediate portions  22 . The second clamp  40  has a second exterior clamp member  42  and a second interior clamp member  44 , and the second exterior clamp member  42  connects to the second interior clamp member  44  via the intermediate portions  22 . 
     As depicted, the exterior and interior clamp members have a general U-shape, although they could be V-shaped, semi-rectangular in shape, or any other semi-annular shape. As depicted, the interior clamp members are located concentrically within the exterior clamp members along the lateral axis  70 . 
     As depicted in  FIG. 1 , the medical device  20  is in a deployed state wherein the exterior clamp members  32  and  42  and the interior clamp members  34  and  44  of the first clamp  30  and the second clamp  40  are coplanar. Coplanar as used herein means perfectly planar and +/−30 degrees away from perfectly planar. 
       FIG. 2  depicts the medical device  20  in the delivery state wherein the exterior and interior clamp members  32 ,  42 ,  34 , and  44  have rotated out of plane toward the longitudinal axis  72  so that the first exterior clamp member  32  is adjacent to the second exterior clamp member  42  and the first interior clamp member  34  is adjacent to the second interior clamp member  44 . The clamp members typically will rotate about 60° to about 110° degrees away from the lateral axis  70 . 
     In the embodiment shown in  FIGS. 1 and 2 , the clamp members are biased toward forming the deployed state as depicted in  FIG. 1 . The medical device  20  is shown as being formed of a flat metal—preferably nitinol—having a round or rectangular (flat) cross-sectional shape, although other constructions may be employed (e.g., a round wire). Preferably, the metal has a thickness in the range of about 0.001 to about 0.1 inches, and more preferably from about 0.008 to about 0.028 inches. For example, the medical device  20 , or the clamp members individually, may be comprised of other metals, metal alloys, plastics, or other materials that have suitable resiliency, whereby the clamp members can move according to the natural or imposed shape-memory characteristics of the clamp members. The medical device  20 , or the clamp members individually, may also be comprised of resorbable or degradable materials, but preferably the material would not substantially degrade or lose structural integrity until formation of the anastomosis was complete. As used herein, resorbable refers to the ability of a material to be absorbed into a tissue and/or bodily fluid upon contact with the tissue and/or bodily fluid. A number of resorbable materials are known in the art, and any suitable resorbable material may be used. Examples include resorbable homopolymers, copolymers, or blends of resorbable polymers. As used herein, degradable refers to the ability of a material to dissipate upon implantation within a body within a clinically reasonable amount of time, independent of the mechanisms by which dissipation can occur, such as dissolution, degradation, absorption and excretion. A number of degradable materials are known in the art, and any suitable degradable material may be used. Examples include polyethylene, polypropylene and polyoxypropylene glycolic sugars, as well as polylactic sugars. 
     In addition, the medical device  20  is shown as comprising one solid piece of metal. In alternative embodiments, the intermediate portions  22  may be fastening devices known in the art, such as hinges, springs, or other rotatable couplings known in the art. In these embodiments, the clamp members need not have shape-memory characteristics. Moreover, while the first and second clamps  30  and  40  make up one unitary device as depicted in  FIGS. 1 and 2 , the medical device  20  may comprise two separate clamp members (not shown), or it may comprise four separate clamp members (not shown). 
     Referring again to  FIG. 1 , an interior space  74  exists between the exterior clamp members and the interior clamp members. The distance S between the exterior clamp members and the interior clamp members may range from about 0 to about 8 mm. A second interior space  76  exists between the first and second interior clamp members  34  and  44 . The horizontal distance D between the two intermediate portions  22  may range from about 0 to about 25 mm, and the lateral distance L from the first interior clamp member  34  to the second interior clamp member  44  may range from about 5 mm to about 50 mm. 
     A medical apparatus  66  for forming an anastomosis will now be described with reference to  FIGS. 3A to 5 . The medical apparatus  66  includes a medical device for forming, creating, and maintaining an anastomosis, an elongate member for delivering the medical device, and, optionally, a tubular cap for retaining the medical device on or near the elongate member. According to one embodiment shown in  FIG. 3A , the medical device  20  is shown loaded within a tubular cap  64  and adjacent to a distal end  62  of an elongate member, in this case an endoscope  60 . The endoscope  60  may be any type of scope known in the art, or may alternatively be any flexible elongate member suitable for being inserted into the body for therapeutic purposes. The medical device  20  is held in the delivery configuration by the tubular cap  64 . In this embodiment, a control wire  61  is passed through an accessory channel  65  and is connected to a pusher  63 . The control wire  61  in combination with the pusher  63  is used to move the exterior clamp members  32  and  42  distally beyond the distal end  67  of the tubular cap  64  so that the exterior clamp members  32  and  42  may be released into their deployed states. The control wire  61  and pusher  63  are then further extended to deploy the interior clamp members  34  and  44 . Alternatively, the medical device  20  could be loaded into the endoscope  60  itself, and the endoscope  60  would maintain the medical device  20  in the delivery configuration. 
     Referring now to  FIG. 4 , the medical device  20  has been inserted distally through a first stoma  52  in a first bodily wall  50  (e.g., the stomach) and through a second stoma  58  in a second bodily wall  56  (e.g., the small intestine, and typically, the jejunum) to rest within the interior  57  of the second bodily wall  56 . In this embodiment of the apparatus, the control wire  61  and pusher  63  have been advanced by the clinician in the distal direction, thereby moving the exterior clamp members  32  and  42  beyond the distal end  67  of the tubular cap  64  and allowing the exterior clamp members  32  and  42  to move to their deployed states. Releasing the exterior clamp members  32  and  42  into their deployed states causes the exterior clamp members  32  and  42  to exert pressure on the interior surface of the second bodily wall  56 . 
     Referring now to  FIG. 5 , the apparatus  66  has been retracted so that the second bodily wall  56  is brought proximate to the first bodily wall  50 , and the interior clamp members  34  and  44  are located proximal to the first bodily wall  50 . The control wire  61  and pusher  63  are further extended, thereby releasing the interior clamp members  34  and  44  into their deployed states, causing the interior clamp members  34  and  44  to exert pressure on the interior surface of the first bodily wall  50 . Alternatively, or in conjunction with the control wire  61 , the whole apparatus  66  can be pulled proximally and the tension of the exterior clamp members  32 ,  42  on the second bodily wall  56  can pull the interior clamp members  34 ,  44  out of the tubular cap  64  by overcoming the friction therebetween. The medical device  20  could also be loaded such that interior clamp members  34  and  44  are located distal to the exterior clamp members  32  and  42  such that the interior clamp members  34  and  44  are deployed within the interior  57  of the second bodily wall  56 , and the exterior clamp members  32  and  42  are deployed within an interior  51  of the first bodily wall  50  (not shown). 
     There are alternative ways to facilitate the deployment of the medical device  20  within the two stomas  52  and  58 . One embodiment is depicted in  FIG. 3B . In this embodiment, a tether is used to move the medical device  20  distally out from the tubular cap  64 . The tether may be a suture or strap or other material known in the art, and may be affixed to the medical device  20  via knots, catches, enlargements, by tying it, or through other means known in the art, or may merely be located adjacent to and engaged by friction between the medical device  20  and the tubular cap  64 . In the embodiment depicted in  FIG. 3B , the tether is a suture  69  tied to the medical device  20 . When the clinician pulls the suture  69  proximally, the medical device  20  is moved distally so that exterior clamp members  32  and  42  are no longer constrained by the tubular cap  64 , thereby allowing them to move to their deployed states. Pulling further proximally on the suture  69  causes the interior clamp members  34  and  44  to move to their deployed states once they are no longer constrained by the tubular cap  64 . The suture may then be excised by the clinician via a cutting device advanced through a working lumen (not shown) in the endoscope  60 . 
     Referring now to  FIGS. 6-9 , alternative embodiments of the medical device and the tubular cap are shown.  FIG. 6  depicts an alternative embodiment of the medical device  20 ′. In medical device  20 ′, the exterior and interior clamp members  32 ′,  42 ′,  34 ′, and  44 ′ rotate at locations further away laterally from the intermediate portion  22 ′ than the exterior and interior clamp members  32 ,  42 ,  34 , and  44  do from intermediate portion  22  in medical device  20 . This difference in rotation allows the medical device  20 ′ to better fit within the retractable cap  73  depicted in  FIG. 7  and the tubular cap  83  depicted in  FIG. 9 . 
       FIG. 7  depicts an embodiment of the tubular cap  64  wherein the tubular cap  64  is a retractable cap  73 . The retractable cap  73  is comprised of a fixed end portion  75  and a retractable hood  77  that is slidably mounted on the exterior of the fixed end portion  75 . The retractable hood  77  contains two control wings  86  opposite each other that maintain the exterior clamp members  32 ′ and  42 ′ in their delivery configurations. The retractable cap  73  may be placed on an endoscope  60 , or it may be placed on a separate elongate member, such as a catheter, that runs alongside the endoscope  60  either freely or on a wire guide (not shown). Two external drive wires  79  are attached to the retractable hood  77 . Referring now to  FIGS. 7-8 , a clinician may pull proximally on the drive wires  79 , which will move the retractable hood  77  proximally, and will release and deploy the exterior clamp members  32  and  42 . The interior clamp members  34  and  44  may be released and deployed either by pushing the medical device  20  in the distal direction, for example by using a control wire  61  and pusher  63  as discussed above, or by pulling the endoscope  60  away in the proximate direction. 
     Referring now to  FIG. 9 , another embodiment of the tubular cap  64  is shown.  FIG. 9  depicts a tubular cap  83  with grooves  81  contained on the interior of two control wings  86 ′. The control wings  86 ′ maintain the exterior clamp members  32 ′ and  42 ′ in the delivery configuration. The grooves  81  better allow a tether to be used in conjunction with the tubular cap  83  by holding the tether in place. Alternatively, a perfectly cylindrical cap may be used as depicted in  FIGS. 3A-5 . Other shapes and designs may be used and will be known to those of skill in the art. 
     A medical method for creating an anastomosis will now be described with reference to  FIGS. 3A-5 , and  11 - 12 . Before fully deploying the medical device  20  to create an anastomosis, stomas must be created in the desired viscera, and the stomas must be brought within proximity of each other. One way to achieve this goal would be to load the medical device  20  within a tubular cap  64  at the distal end  62  of an endoscope  60  as depicted in  FIGS. 3A-5 , and then advance the endoscope to the first viscera. A cutting device (not shown) could be advanced through a working lumen of the endoscope  60  and could be used to create the first stoma  52  in the first bodily wall  50  of the first viscera. The endoscope  60  could be further advanced to the second viscera, and the cutting device could be used to create the second stoma  58  in the second bodily wall  56 . The exterior clamp members  32  and  42  could be deployed as described above, and then the medical device  20 , endoscope  60  and tubular cap  64 , and the second bodily wall  56  could be retracted toward the first stoma  52  in the first bodily wall  50 . Once the medical device  20  is properly positioned such that the interior clamp members  34  and  44  are located proximal to the first bodily wall  50 , the interior clamp members  34  and  44  could be released as described above and the anastomosis would be created. 
     The stomas may also be created and brought into proximity with one another prior to insertion of the medical device  20 . There are numerous ways of achieving this that are known in the art, some of which are described in U.S. Nonprovisional application Ser. No. 12/025,985, filed Feb. 5, 2008, which is incorporated by reference herein in its entirety. Laparoscopic surgery or open surgery and devices used in those types of surgeries may also be employed to create the stomas and to hold them in place proximal to each other to prepare for the insertion of the medical device  20 . 
     Once the stomas have been created and the medical device  20  has been deployed via the elongate member as described above and depicted in  FIGS. 3A-5 , the force exerted by the interior clamp members  34  and  44  against the first bodily wall  50  and the force exerted by the exterior clamp members  32  and  42  against the second bodily wall  56  compress the two bodily walls and hold them proximate to each other. The compression exerted on the bodily walls by the exterior and interior clamp members will result in necrosis of the tissues of the two viscera that are contained between the clamp members, thus resulting in an even larger anastomosis after a few days or a week, depending on the thickness of the tissues and the strength of the material used for the clamp members. If a larger anastomosis is immediately desired, a knife or other cutting device may be used to excise the tissue from the two bodily walls by cutting from the interior  80  laterally toward the apex of the first interior clamp member  34  to create a larger opening  82  as depicted in  FIG. 12 . Additionally, an incision may be extended laterally from the interior  80  to the apex of the second interior clamp member  44  to form a second larger opening  84 , so that one large, continuous anastomosis is now formed. 
     An alternate method for creating an anastomosis will now be described with reference to  FIGS. 4-5 ,  10  and  13 . In this method, a gastronomy would be created as described above, and then two screw retractors  110  attached to torque cables  112  would be advanced through the first stoma  52  of the first bodily wall  50  and anchored to the proximal side of the second bodily wall  56  on either side of the second stoma  58  as depicted in  FIG. 13 . The clinician would then remove the endoscope  60 , leaving the anchored screw retractors  110  and torque cables  112  extending proximally and exiting the patient&#39;s mouth. The medical device  90 , which as depicted in  FIG. 10  is substantially identical to medical device  20  except that it has been modified to include two large holes  100  to fit over the torque cables  112 , would then be constrained in a delivery state similar to the delivery states of medical device  20  depicted in  FIG. 2  and medical device  20 ′ depicted in  FIG. 6 . The length L′ between first interior clamp member  98  and second interior clamp member  94  ranges from about 5 mm to about 50 mm, and the horizontal distance D′ ranges from about 0 mm to about 25 mm. 
     As depicted in  FIG. 13 , a suture  114  is advanced through holes  102  to keep the interior clamp members  98  and  94  adjacent to each other in the delivery state, and another suture  116  would be advanced through holes  104  in first exterior clamp member  96  and second exterior clamp member  92  to hold them adjacent to each other in the delivery state and located distally to the interior clamp members  98  and  94 . It would be known by those of skill in the art that rings, bands, or other materials may be used in place of the sutures  114  and  116 . The medical device  90  in the delivery state is loaded on to the torque cables  112  by inserting the proximal end of the torque cables  112  through the large holes  100  in the medical device  90 . 
     Referring still to  FIG. 13 , the medical device  90  would then be advanced over the torque cables  112  through the first stoma  52  until the exterior clamp members  96  and  92  have advanced through the second stoma  58 . The clinician may optionally pull proximally on the torque cables  112  in order to pull the tissue of the second bodily wall  56  proximate to the exterior clamp members  96  and  92 . The clinician will then release the exterior clamp members  96  and  92  by pulling on or excising the suture  116 , thereby causing the exterior clamp members  96  and  92  to deploy and exert pressure on the interior surface of the second bodily wall  56 . The clinician will then pull proximally on the torque cables  112  until the second stoma  58  is adjacent to the first stoma  52  and the interior clamp members  98  and  94  are proximate to the first stoma  52 . The clinician will then release the interior clamp members  98  and  94  to their deployed states in the same manner in which the exterior clamp members  96  and  92  were released, causing the interior clamp members  98  and  94  to exert pressure on the interior surface of the first bodily wall  50 . The clinician then removes the screw retractors  110  and the torque cables  112  by pulling them proximally away from the newly formed gastronomy. 
     Removal of the medical device  20 , medical device  20 ′, or medical device  90  may be completed through natural means. The pressure exerted on the bodily walls  50  and  56  will cause necrosis over a number of days, thereby forming an anastomosis that is slightly larger than interior  80  or interior  80  and openings  82  and  84  combined. After a certain amount of necrosis occurs, the medical devices  20 ,  20 ′, and  90  will dislodge and pass through the body naturally. Or, the medical devices  20 ,  20 ′, and  90  may be made of degradable or resorbable materials so that it will be naturally broken down by the body. 
     It will be recognized by those skilled in the art that during these anastomosis formation procedures, the area of compression of the bodily walls  50  and  56  provides a barrier that guards against leakage of the GI contents or other bodily fluids depending on the viscera involved. Likewise, the anastomosis is formed with surety before the patient leaves the medical facility, eliminating the need for a follow-up procedure. Moreover, because interior clamp members  34  and  44  maintain the size of the anastomosis, there is no need for a second procedure to insert a stent to maintain the opening. 
     While various embodiments of the invention have been described, the invention is not to be restricted except in light of the attached claims and their equivalents. Moreover, the advantages described herein are not necessarily the only advantages of the invention and it is not necessarily expected that every embodiment of the invention will achieve all of the advantages described.

Technology Category: 1