Patent Abstract:
An anastomotic ring device for forming a hollow rivet (ring) attachment between tissue lumens facilitates laparoscopic or endoscopic implantation by including features that facilitate actuation from a stressed, generally cylindrical shape. Economical manufacturer is achieved by weaving open ended strands into a generally cylindrical stent shape that is imparted with a Shape Memory Effect (SME) to actuate to a hollow rivet (ring) shape. Alternatively or in addition to SME inherent in the woven strands, an actuating force may be received from a helical spring element incorporated into the ring. Self-actuating ring devices are enhanced by forming woven strands into petals that diverge from opposing petals such that the strands encounter less friction when actuating. Each of these features alone or in combination enhance clinical use of anastomotic ring devices, such as a bariatric gastric bypass procedure.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application is related to four co-pending and commonly-owned application filed on even date herewith, the disclosure of each is hereby incorporated by reference in its entirety:  
         [0002]     “Applier For Fastener For Single Lumen Access Anastomosis”, Ser. No. ______ to Mark Ortiz;  
         [0003]     “Unfolding Anastomosis Ring Device”, Ser. No. ______ to Jean Beaupre;  
         [0004]     “Single Lumen Access Deployable Ring for Intralumenal Anastomosis”, Ser. No. ______ to Mark Ortiz; and  
         [0005]     “Single Lumen Anastomosis Applier for Fastener”, Ser. No. _____ to Mark Ortiz, Robert McKenna, Bill Kraimer, Mike Stokes, and Foster Stulen. 
     
    
     FIELD OF THE INVENTION  
       [0006]     The present invention relates, in general, to surgery and, more particularly, to a method of performing a surgical procedure on the digestive system.  
       BACKGROUND OF THE INVENTION  
       [0007]     The percentage of the world population suffering from morbid obesity is steadily increasing. Severely obese persons are susceptible to increased risk of heart disease, stroke, diabetes, pulmonary disease, and accidents. Because of the effect of morbid obesity to the life of the patient, methods of treating morbid obesity are being researched.  
         [0008]     Numerous non-operative therapies for morbid obesity have been tried with virtually no permanent success. Dietary counseling, behavior modification, wiring a patient&#39;s jaws shut, and pharmacologic methods have all been tried, and though temporarily effective, failed to correct the condition. Further, introducing an object in the stomach, such as an esophago-gastric balloon, to fill the stomach have also been used to treat the condition; however, such approaches tend to cause irritation to the stomach and are not effective long-term.  
         [0009]     Surgical treatments of morbid obesity have been increasingly used with greater success. These approaches may be generalized as those that reduce the effective size of the stomach, limiting the amount of food intake, and those that create malabsorption of the food that it is eaten. For instance, some patients benefit from adjustable gastric bands (AGB) that are advantageously laparoscopically placed about the stomach to form a stoma of a desired size that allows food to fill an upper portion of the stomach, causing a feeling of satiety. To allow adjustment of the size of the stoma after implantation, a fluid conduit communicates between an inwardly presented fluid bladder of the AGB to a fluid injection port subcutaneously placed in front of the patient&#39;s sternum. A syringe needle may then inject or withdraw fluid as desired to adjust the AGB.  
         [0010]     Although an effective approach to obesity for some, other patients may find the lifestyle changes undesirable, necessitated by the restricted amount of food intake. In addition, the medical condition of the patient may suggest the need for a more permanent solution. To that end, surgical approaches have been used to alter the portions of the stomach and/or small intestine available for digesting food. Current methods of performing a laparoscopic anastomoses for a gastric bypass include stapling, suturing, and placing biofragmentable rings, each having significant challenges. For instance, suturing is time consuming, as well as being technique and dexterity dependent. Stapling requires placement of an anvil, which is a large device that cannot be introduced through a trocar port. Having to introduce the port through a laparotomy presents an increased incidence of wound site infection associated with intralumenal content being dragged to the laparotomy entry site.  
         [0011]     As an example of the latter approach, in U.S. Pat. No. 6,543,456 a method for gastric bypass surgery includes the insertion of proximal and distal anastomosis members (e.g., anvils) transorally with grasping forceps. The stomach and the small intestine are transected endoscopically by a surgical severing and stapling instrument to create a gastric pouch, a drainage loop, and a Roux limb. An endoscopically inserted circular stapler attaches to the distal anastomosis member to join the drainage loop to a distal portion of the intestine, and the circular stapler attaches to the proximal anastomosis member to join the Roux limb to the gastric pouch. Thereafter, the anastomosis members are removed to create an orifice between joined portions of the stomach and intestine. This method reduces the number of laparoscopic ports, avoids a laparoscopic insertion of an anastomosis instrument (e.g., circular stapler) into an enlarged surgical port, and eliminates the need for an enterotomy and an enterotomy closure.  
         [0012]     While methods such as that described are a marked improvement over generally known gastric bypass and similar surgical treatments for morbid obesity, it would be desirable to achieve a gastric bypass with yet fewer procedural steps and with fewer laparoscopic insertions. Such an approach is described in U.S. Pat. Appl. Publ. No. US 2003/0032967 to Park et al., wherein gastrointestinal or enteric (including biliary) anastomosis is achieved by insertion of a sheath that perforates the walls of two tissue passages, such as the stomach and small intestine. A three-dimensional woven tube of wire of having a thermal shape memory effect (SME) (“generally-known nitinol ring device”) is presented by a cannula of the sheath on both sides of the openings. Deployment of the woven tube causes the outer loops or ends of the tube to fold or loop back to hold the lumenal interface of the anastomosis site in apposition. Thereby, the need for a mechanical compression component in a delivery system is reduced or avoided, reducing the size and complexity of the delivery device.  
         [0013]     While the generally-known nitinol ring device is a significant advancement in the treatment of morbid obesity, it is believed that further improvements would be desirable. For instance, the continuous interlocking petals are difficult to manufacturer, especially since the depicted woven tube is of a continuous wire loop bent into a pattern of interlocking triangles.  
         [0014]     In addition, the generally-known nitinol ring device is a woven tube, or stent, that is purported to be a self-actuating anastomotic ring. However, the disclosed stent sometimes will not actuate or transform completely from its stressed cylindrical state to its relaxed clamping state, perhaps due to irregularities in undulations of its weaved designs create friction. One particular difficulty of known SME anastomotic rings are that they are designed to move from a generally cylindrical shape to a hollow rivet shape (“ring shape”) by having wires that form the device move across one another. In particular, wires must move within a nodal point (i.e., an indentation or valley) created by the wire bend and must climb back out of the indentation. In some instances, the device fails to fully actuate on its own due to these sources of friction.  
         [0015]     Consequently, there is a general need for an approach to anastomosis that will use existing trocar ports (e.g., 12 mm size) with a minimum of suturing. Moreover, aspects of the method should have application to endoscopic surgery. To that end, a significant need exists for an anastomosis device that reliably and effectively deploys and actuates to eliminate the need for surgical stapling and suturing to form an anastomosis.  
       BRIEF SUMMARY OF THE INVENTION  
       [0016]     The invention overcomes the above-noted and other deficiencies of the prior art by providing an anastomosis device woven from one or more strands with end disconnected from other ends, providing a more economical manufacture.  
         [0017]     In one aspect of the invention, a woven tube anastomotic device has each longitudinal end of its constituent strands terminate in circumferential petals. The unactuated position of the tube is of a generally cylindrical shape and the actuated position of a hollow rivet shape for insertion through and for forming an anastomotic attachment between two proximate tissue walls, respectively. An actuation force is provided by weaving a helical coil spring into the woven tube. Thereby, enhanced actuation force may be achieved without relying solely or at all upon the rest of the woven tube.  
         [0018]     These and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof. 
     
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0019]     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.  
         [0020]      FIG. 1  is perspective view of an applier having an anastomotic ring device installed thereon being inserted laparoscopically to an anastomosis target site on each of two portions of a patient&#39;s small intestine.  
         [0021]      FIG. 2  is a perspective detail view of the applier with sheath retracted and anastomosis target site of  FIG. 1 , depicting the anastomotic ring device in its undeployed, unactuated state.  
         [0022]      FIG. 3  is a perspective, exploded and partially cutaway view of a distal portion of the applier of  FIG. 1 .  
         [0023]      FIG. 4  is a perspective, exploded view of a proximal portion of the applier of  FIG. 1  with a left housing half omitted.  
         [0024]      FIG. 5  is perspective view of the applier of  FIG. 1  with the left housing half omitted and an outer tube of the cannula partially cutaway to expose an intermediate tube and inner rod that actuate a molded actuating member that actuates the omitted anastomotic ring device, also to expose a deployment illuminator that allows confirming actuation of an anastomotic ring device by viewing through the translucent tissue walls.  
         [0025]      FIG. 6  is a perspective view of the applier of  FIG. 5  with the triggers and molded actuating member in an actuated position.  
         [0026]      FIG. 7  is a perspective view of the applier of  FIG. 1  in a partially actuated state.  
         [0027]      FIG. 8  is a detail perspective view of a distal portion of the applier of  FIG. 7  with tissue walls partially cutaway.  
         [0028]      FIG. 9  is a perspective view of the applier of  FIG. 1  in a fully actuated state.  
         [0029]      FIG. 10  is a detail perspective view of the distal portion of the applier of  FIG. 9  with tissue walls partially cutaway.  
         [0030]      FIG. 11  is a detail perspective view of the distal portion of the applier returned to unactuated state and withdrawn proximally to deploy the actuated anastomotic ring device.  
         [0031]      FIG. 12  is a detail perspective view of the distal portion of the applier of  FIG. 1  in an unactuated position holding an anastomotic ring device advantageously fabricated with a ball end discontinuous weave.  
         [0032]      FIG. 13  is a detail perspective view of the distal portion of the applier of  FIG. 12  in a partially actuated position.  
         [0033]      FIG. 14  is a detail perspective view of the distal portion of the applier of  FIG. 12  in a fully actuated position.  
         [0034]      FIG. 15  is an end view of the anastomotic ring device of  FIG. 12  after actuation, depicted as a single strand discontinuous weave with a pair of ball ends.  
         [0035]      FIG. 16  is an end view of the anastomotic ring device of  FIG. 12  after actuation, depicted as a dual strand discontinuous weave, each strand with a pair of ball ends.  
         [0036]      FIG. 17  is a detail view of a ball end of the anastomotic ring device of  FIG. 12  in atraumatic contact with a tissue wall.  
         [0037]      FIG. 18  is a detail perspective view of the distal portion of the applier of  FIG. 1  in an unactuated position holding an anastomotic ring device advantageously fabricated with a loop end discontinuous weave.  
         [0038]      FIG. 19  is a detail perspective view of the distal portion of the applier of  FIG. 18  in a partially actuated position.  
         [0039]      FIG. 20  is a detail perspective view of the distal portion of the applier of  FIG. 18  in a fully actuated position.  
         [0040]      FIG. 21  is an end view of an anastomotic ring device after actuation, depicted as a dual strand discontinuous weave each strand with straight ends.  
         [0041]      FIG. 22  is an end view of the anastomotic ring device of  FIG. 18  after actuation, depicted as a dual strand discontinuous weave, each strand with a pair of loop ends.  
         [0042]      FIG. 23  is a detail view of a loop end of the anastomotic ring device of  FIG. 18  in atraumatic contact with a tissue wall.  
         [0043]      FIG. 24  is a detail perspective view of the distal portion of the applier of  FIG. 1  in an unactuated position holding an anastomotic ring device advantageously fabricated with a hook end discontinuous weave.  
         [0044]      FIG. 25  is a detail perspective view of the distal portion of the applier of  FIG. 24  in a partially actuated position.  
         [0045]      FIG. 26  is a detail perspective view of the distal portion of the applier of  FIG. 24  in a fully actuated position.  
         [0046]      FIG. 27  is an end view of an anastomotic ring device after actuation, depicted as a dual strand discontinuous weave each strand with a pair of hook ends.  
         [0047]      FIG. 28  is a detail view of a loop end of the anastomotic ring device of  FIG. 24  in traumatic contact with a tissue wall.  
         [0048]      FIG. 29  is a side view of an anastomotic ring device including a helical actuation coil and constrained within a sheath.  
         [0049]      FIG. 30  is a perspective view of the anastomotic ring device of  FIG. 30  in an actuated condition.  
         [0050]      FIG. 31  is a side view of a generally known anastomotic ring having converging distal petals.  
         [0051]      FIG. 32  is a detail view of the generally-known anastomotic ring of  FIG. 31 .  
         [0052]      FIG. 33  is a perspective view of an anastomotic ring device incorporating diverging petals.  
         [0053]      FIG. 34  is a side detail view of the diverging petals of the anastomotic ring device of  FIG. 33 .  
         [0054]      FIG. 35  is side view of two arcuate members with a reduced radius point for an anastomotic ring device. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0055]     Turning to the Drawings, wherein like numerals denote like components throughout the several views,  FIG. 1  depicts an applier  10  that advantageously laparoscopically or endoscopically deploys and actuates an anastomotic ring device  12  from a generally cylindrical shape to one having properties of a hollow rivet, or ring, capable of forming an astomotic attachment at an anastomosis target site, such as in a bariatric gastric bypass of a morbidly obese patient  16 . In the illustrative version, the anastomotic ring device  12  comprises a shape memory effect (SME) material such as nitinol that further assists in actuation to an engaging hollow rivet shape. As will be described in greater detail below, various improvements to the configuration of the anastomotic ring device  12  simplify manufacturer as well as adding therapeutic features. Moreover, configuration improvements further assist in actuating the anastomotic ring device  12  without wholly relying upon SME properties of the anastomotic ring device  12 .  
         [0056]     It will be appreciated that the terms “proximal” and “distal” are used herein with reference to a clinician gripping a handle of the applier  10 . It will be further appreciated that for convenience and clarity, spatial terms such as “right”, “left”, “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and absolute. In addition, aspects of the invention have application to surgical procedures performed endoscopically and laparoscopically, as well as an open procedure. Use herein of one of these or similar terms should not be construed to limit the present invention for use in only one category of surgical procedure.  
         [heading-0057]     Anastomotic Ring Device Applier.  
         [0058]     In  FIG. 2 , the applier  10  has the anastomotic ring device  12  advantageously retained in a generally cylindrical shape distal to an outer tube  18  upon a molded actuation member  20  forming a cannula  22  that distally terminates in a tapered tip  24 . This tapered tip  24  presents a distal piercing surface  26  to form an anastomotic opening  28  through apposite tissue walls  30 ,  32  of two gastrointestinal passages. As discussed below, the tapered tip  24  may advantageously include illumination features that allow confirmation of placement and actuation of the anastomotic ring device  12  when viewed from a proximal direction through translucent tissue walls  30 ,  32 .  
         [0059]     With reference to  FIGS. 2-5 , a handle  34 , proximal to the cannula  22 , includes a pair of longitudinally aligned triggers  36 ,  38 . The proximal trigger  36 , shown at its most proximal, unfired position, is coupled to proximal leaves  40  of the molded actuation member  20  via an intermediate tube  42  of the cannula  22 . Distal movement of the proximal trigger  36  thus causes longitudinal distal movement of the intermediate tube  42  and proximal leaves  40 , which outwardly actuate like an umbrella by a hinged relationship to a central portion  44  of the molded actuation member  20 . Similarly, the distal trigger  28 , shown at its most distal, unfired position, is coupled to distal leaves  46  of the molded actuation member  20  via an internal rod  48  that is coupled for movement within the intermediate tube  42 . Proximal movement of the distal trigger  38  causes longitudinal proximal movement of the rod  48  and distal leaves  50  of the molded actuation member  20 , which outwardly actuate by a hinged relationship to the central portion  44 .  
         [0060]     As best viewed in  FIGS. 4-5 , within the handle  34 , a cavity  52  includes proximal and distal apertures  54 ,  56  to allow the longitudinal movement of the proximal and distal triggers  36 ,  38  respectively. Each trigger  36 ,  38  includes a right opening aperture  58  that engage for longitudinal movement a leftward projecting track  60  formed within the cavity  52  of a right half shell of the handle  34 .  
         [0061]     Moving from most distal to most proximal, a first, second and third lateral ridge  62 ,  64 ,  66  across the bottom of the cavity  52  define a first, second, third, and fourth cavity segment  68 ,  70 ,  72 ,  74  respectively. A first block  76 , formed from left and right halves  78 ,  80  is positioned for movement within the first cavity segment  68 . A longitudinal central hole  82  defined between the two halves  78 ,  80  engages and moves with a terminating proximal end  84  of the intermediate tube  42 . The internal rod  48  passes on through the first block  76  into the second, third and fourth cavity segments  70 - 74  into sliding contact with a hole  86  passing through a proximal end  88  of the handle  34 . A second spacer block  90  locked within the second cavity segment  70  has a longitudinal central hole  92  defined between its left and right halves  94 ,  95  that slidingly contacts and support the internal rod  48 . A third sliding block  96  has a longitudinal central hole  98  defined between its upper and lower halves  100 ,  102  that engage and move with the internal rod  48 . A lower portion  104  of the distal trigger  38  is attached to a distal face of the third sliding block  96 . A fourth sliding block  106  within the fourth cavity segment  74  has a longitudinal central hole  108  that slidingly contacts the internal rod  48 . A lower portion  114  of the proximal trigger  36  is attached to a proximal face of the fourth sliding block  106 . A link  116  is attached to the left sides of the first and fourth sliding blocks  76 ,  106 .  
         [0062]     In  FIG. 6 , the triggers  36 ,  38  have been slid toward one another to actuate the molded actuating member  20 . Specifically, the distal trigger  38  has been moved proximally, moving the third sliding block  96  and internal rod  48 , the distal terminating end of the latter being attached to tapered tip  24 . The tapered tip thus moves toward the distal end of the intermediate tube  42 . The proximal trigger  36  has been moved distally, moving fourth sliding block  106 , link  116 , first sliding block  76 , and intermediate tube  42  also distally. The molded actuating member  20  is compressed between the inwardly moving tapered tip  24  and intermediate tube  42 . The distal leaves  50  actuate lateral to the longitudinal axis, and move toward and interdigitate with the proximal leaves  40 . This movement expedites actuating of an anastomotic ring device (not shown in  FIG. 6 ).  
         [0063]     In use, the tapered tip  24  of the applier  10  is inserted through a trocar port into a tissue passage that has been placed proximate to another tissue passage that are to be anastomotically joined (See  FIGS. 1-2 ). The tapered tip  24  and a distal half of the molded actuating member  20  and anastomotic ring device  12  are inserted through an anastomotic opening  28  formed therebetween and then the applier is actuated, with a partially actuated applier  10  being depicted in  FIGS. 7-8 . With particular reference to  FIG. 8 , the proximal and distal leaves  40 ,  50  are shown as having gripping slots  118  that grip respective petals  120  of the anastomotic ring device  12 , especially in its unactuated, generally cylindrical shape. An inwardly directed retention tip  121  or other gripping features in the gripping slots  118  may be incorporated to enhance retention. These gripping slots  118  assist in preventing the anastomotic ring device  12  from slipping off of the applier  10  or being inappropriately placed thereon for actuation. In  FIGS. 9-10 , the applier  10  has been fully actuated, forming the anastomotic ring device  12  into a hollow rivet shape to form the anastomotic attachment between tissue walls  30 ,  32 . The fully actuated proximal and distal leaves  40 ,  50  cause the petals  120  to disengage from the gripping slots  118 . Thereafter, the applier  10  is returned to an unactuated condition and the actuated anastomotic ring device  12  deployed by withdrawing the tapered tip  24  from the anastomotic opening  28  and ring device  12 , as depicted in  FIG. 11 .  
         [heading-0064]     Deployment Illumination.  
         [0065]     In  FIGS. 7, 9 , a distal portion of the anastomotic ring device  12  are depicted in phantom to illustrate their actuated position. This phantom depiction is also suggestive of a clinical advantage of being able to view the deployment condition from a proximal point of view. Typically, an endoscope will view the anastomotic opening  28  from a proximal position. Returning to FIGS,  2 - 7 , adding a deployment illumination feature to the applier  10  provides this ability to view deployment through translucent tissue walls. Specifically, an illumination power source (e.g., battery)  150  and control (e.g., switch)  152  are incorporated into the handle  34  with a conductor, depicted as a twisted wire pair  154  passing through the internal rod  48  to the tapered tip  24 , which includes a proximally directed electroluminescence device  156 . Alternatively conductive ink traces may be applied longitudinally down portions of the applier  10  to provide an electrical circuit to the tapered tip  24 . An externally accessible push button  158  drives the power source  150  against the control  152 , creating an illumination circuit with the electroluminescence device  156 .  
         [0066]     Alternatively or in addition, the molded actuating member  20  may be formed of a fluorescent or electroluminescent material that is either stimulated prior to insertion or receives light from a light source of the applier  10 .  
         [heading-0067]     Discontinuous Weave Anastomotic Ring Device.  
         [0068]     Forming an anastomotic ring device with a continuous wire loop poses a difficult manufacturing process that includes joining the ends of the woven wire strand or forming a weave from a continuous wire loop. In  FIGS. 12-17  an advantageous approach to fabricating an anastomotic ring device  212  includes adding ball ends  214  to each wire strand  216 . In an illustrative embodiment, a hole is laser formed in each ball end  214  and then the ball end  214  is crimped onto the wire strand  216 . The ball ends  214  assist in preventing unraveling of petals  218  formed by the woven strands  216 . In addition, the ball ends  214  form an atraumatic contact with a tissue wall  220 , as depicted in  FIG. 17 .  
         [0069]     As an alternative discontinuous weave, an anastomotic ring device  312  in  FIGS. 18-23  is formed by one or more wire strands  316  whose ends are not attached to one another but instead positioned within the confines of petals  318  of the anastomotic ring device  312 . Specifically, in  FIG. 21 , each strand  316  terminates in a generally straight end  322 . In  FIGS. 18-20 ,  22 - 23 , each strand terminates in a loop end  324 . In each instance, positioning each end  322 ,  324  within petals  318  of the anastomotic ring device  312  avoids interference with an applier while also simplifying manufacturer.  
         [0070]     As yet a further alternative discontinuous weave, an anastomotic ring device  412  in  FIGS. 24-28  is formed by one or more wire strands  416  whose ends are not attached to one another but instead are positioned outside of petals  418  of the woven strands  416 . In a depicted version, each strand  416  traumatically engages a tissue wall  420  with hook ends  426  interdigitated between the petals  416 .  
         [heading-0071]     Spring Closed Ring Anastomotic Device.  
         [0072]     In  FIGS. 29-30 , an anastomotic ring device  512  includes a helical wire assist spring  530  fabricated from an SME material (e.g., nitinol) or from spring steel. Thus, the woven material of a stent portion  532  of the anastomotic ring device  512  need not be of an SME material, or at least need not rely entirely upon its SME properties to effect actuation. The helical wire assist spring  530  enables selection of a stent portion  532  of a desired wire thickness and of a desired material. For instance, the stent portion  532  may even be of plastic or longitudinally cut discrete sections of a continuously woven wire braid that provide no inherent actuating capability.  
         [0073]     In  FIG. 29 , the wire assisted anastomotic ring device  512  is depicted in a generally cylindrical shape constrained by a lumen  534 , which may be an applier. It will be appreciated that the wire assisted anastomotic ring device  512  may advantageously be implanted by use of the applier  10  described above, which would advantageously affirmatively grip the wire assisted anastomotic ring device to hold it in the stressed, unactuated position prior to implantation.  
         [heading-0074]     Deflected Petal Anastomotic Ring Device.  
         [0075]     The generally-known nitinol ring device  600  includes converging looped petals  602  whose distal end flare lateral to the longitudinal axis when viewed in their stressed, generally cylindrical state, and interdigitate when viewed in their relaxed, actuated state, as depicted in  FIGS. 31-32 . It is believed that such deflected petals  602  engage the tissue walls in a beneficial fashion. However, the resulting increase in outward slope of each petal  602  imposes an increasing amount of friction to self-actuation of the generally-known nitinol ring device  600 , negating any advantage of engagement, requiring more force to self-deploy generally-known nitinol ring device  600 .  
         [0076]     As generally-known nitinol ring device  600  deploys, portions of wire forming generally-known nitinol ring device  600  move relative to each other while in contact. The curvature of the wire winding of generally-known nitinol ring device  600  forms local maxima and minima for a contacting wire to traverse. The converging looped petals cause a local minimum for a contacting wire portion that the contacting wire portion must overcome. An increasing force gradient opposing deployment occurs, and must be overcome by the internal stored energy of the generally-known nitinol ring device  600  to complete deployment.  
         [0077]     In  FIGS. 33-34 , an anastomotic ring device  712  advantageously includes distal looped petals  714  that are divergent (flared away) from each other when the ring device  712  is in its relaxed, hollow rivet (ring) shape as depicted. It is further believed that deflecting the distal portions of each petal  714  away from the tissue walls may decrease excessive pressure at the anastomotic attachment site without significant degradation to its required amount of attachment forces. Moreover, for anastomotic ring devices  712  that are not formed of an absorbable material, this configuration may advantageously later more readily detach after the anastomotic attachment is permanently formed between tissue walls.  
         [0078]     Anastomotic ring device  712 , with divergent (flared away) petals, will a cause a maximum in force tending to urge the anastomotic ring device  712  towards the actuated ring state.  
         [0079]     With reference to  FIG. 35 , an anastomotic ring device  812  includes petals  814  whose distal portion  816  is formed with a small radius relative to its more proximal portions  818  that overlap each other and slide across each other during actuation. As depicted, straight portions  820  between the distal and proximal portions  816 ,  818  may be shaped such that in the stressed, cylindrical shape of the ring device  812  that the petals  814  are urged toward the actuated ring state.  
         [0080]     It should be appreciated that the divergent position of the petals may further be enhanced by SME treatment of these distal portions wherein the stressed, generally cylindrical state of the ring device  814  may include a straight petal or even a converging petal for purposes such as enhancing user of an applier  10  and/or achieving a good anastomotic attachment immediately upon actuation with an eventual steady-state actuation position being as depicted.  
         [0081]     While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications may readily appear to those skilled in the art.  
         [0082]     For example, although bariatric procedures for bypassing portions of a gastrointestinal tract are depicted, it should be appreciated that other surgical procedures may benefit by an anastomotic ring device having aspects described herein.  
         [0083]     For another example, although an applier  10  has been advantageously depicted that assists in actuating the anastomotic ring device  10 , it should be appreciated that the anastomotic ring device  10  includes enhanced reliability and performance in self-actuating and thus may be inserted by other means, to include insertion through the opening and released without the application of an external actuating force.  
         [0084]     For yet a further example, various improvements disclosed herein may be used in various combinations.

Technology Classification (CPC): 0