Patent Publication Number: US-2007123840-A1

Title: Instrument assisted abdominal access

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      The present application claims priority to U.S. Provisional Application No. 60/728,382 filed Oct. 18, 2005 which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates to apparatus and methods for transluminal access into a patient body. More particularly, the present invention relates to apparatus and methods for endoluminal transgastric access into regions within the peritoneal space utilizing endoluminal and trans-abdominal access for performing therapeutic and/or diagnostic procedures; also related are methods and apparatus for closing or approximating tissue openings created for the therapeutic and/or diagnostic procedures.  
     BACKGROUND OF THE INVENTION  
      In an effort to reduce the invasiveness of treatments for gastrointestinal (“GI”) disorders, gastroenterologists, GI surgeons and others are pursuing minimally invasive endoluminal treatments for such disorders. Treatments through natural GI passageways are being pursued utilizing instruments advanced per-orally and/or peranally. For example, U.S. Pat. No. 6,572,629 (Kalloo et al.); U.S. Pat. No. 5,297,536 (Wilk); and U.S. Pat. No. 5,458,131 (Wilk), which are incorporated herein by reference in their entirety, show tools and methods for entry into the peritoneal space through the stomach wall.  
      In view of advances in methods and apparatus for minimally invasive endoluminal GI treatment, it would be desirable to provide methods and apparatus for diagnostic or therapeutic treatment of organs of the digestive system or other parts of the body via-instruments advanced per-orally and transgastrically and/or per-anally, or a combination thereof.  
      Transgastric procedures from the interior of the stomach to the exterior have also been described previously in U.S. Pat. Pub. No. 2003/0216613 A1 (Suzuki et al.) However, while that reference discusses curvable overtubes that may be maintained in a curve, it does not describe an overtube or guide that may be shapelocked or rigidized along its length.  
      During endoluminal access into the peritoneal cavity of a patient, once the stomach tissue has been pierced and dilated, insufflation of the stomach is no longer possible. Thus, once the endoscope or instruments are removed from the peritoneal space and withdrawn proximally from the opening within the stomach wall, relocating this opening for closure becomes very difficult for the physician. This problem is compounded by the inability to insufflate the stomach to gain a clear view of the surrounding stomach tissue as well as by the limitations of endoluminal visualization within the stomach.  
      Accordingly, there is also a need for marking or otherwise indicating the location of an opening made within a stomach wall for closing the opening upon the end of a procedure.  
     SUMMARY OF THE INVENTION  
      Methods and apparatus are provided for accessing digestive or other organs (as well as other parts of the body) within the gastrointestinal tract and within the peritoneal cavity. Such regions may be accessed endoluminally and transluminally via instruments passed into the gastrointestinal tract per-orally and/or per-anally and, e.g., transluminally, out of the stomach for performing diagnostic or therapeutic surgical procedures.  
      In one aspect for endoluminally accessing the peritoneal cavity within the patient body, a shape-lockable elongate body may be advanced in a flexible state through a natural orifice, e.g., the patient&#39;s mouth, into the patient body, e.g., stomach. An opening may be created through the tissue wall, e.g., the stomach wall, for accessing the space external to the stomach. The opening through the tissue wall may be created by advancing an incising instrument endoluminally through the patient body. Alternatively, instruments may be passed through the abdominal wall of the patient and into the peritoneal cavity to incise a region of the tissue wall from its exterior surface to create an access opening for the endoluminally delivered instruments into the peritoneal cavity. Moreover, visualization may be facilitated during procedures by additional imaging tools positioned through the abdominal wall. Once the opening has been made, either endoluminally or trans-abdominally, any incisions in the abdominal wall may be closed prior to, during, or after completion of a procedure within the peritoneal cavity of the patient. At least the distal portion of the elongate body may be passed through the opening for providing access to the peritoneal cavity. The elongate body may be transitioned from its flexible state to a rigid state prior to, during, or after advancing the elongate body into the patient.  
      In another aspect, the shape-lockable elongate body may be advanced in its flexible state and the opening may be created through the tissue wall, as above. But a dilation balloon may be advanced through the elongate body and positioned at least partially within the opening within the tissue and within a distal opening of the elongate body. The dilation balloon may then be expanded such that the distal opening of the elongate body is obstructed by the dilation balloon and the opening through the tissue wall is dilated. With the dilation balloon maintained in its position within the distal opening of the elongate body, the elongate body may be advanced through the dilated opening of the tissue wall.  
      In passing an endoscope through the stomach wall, a number of different methods and tools may be employed. For instance, an ablation probe or needle knife maybe advanced through the endoscope lumen into proximity with the stomach wall. The probe or needle knife may be actuated to pierce or cut through the stomach wall to create a gastric opening into the peritoneal cavity. Once a gastric opening of sufficient size, i.e., at least sufficiently large enough to pass a guidewire or probe therethrough, has been created, the needle knife may be removed and a conventional guidewire may be advanced therethrough until the guidewire is passed at least partially within peritoneal cavity.  
      With the guidewire in place, a dilation balloon having an expanded diameter of, e.g., 18 or 20 mm (or greater), may be passed in its unexpanded profile over the guidewire until the dilation balloon is positioned within the gastric opening, where it may then be expanded to thereby dilate the gastric opening. Once the gastric opening has been desirably dilated, the balloon may be deflated and withdrawn. The guidewire may also be withdrawn proximally, if so desired. The endoscope may then be advanced distally through the dilated gastric opening for entry into the peritoneal cavity where any number of diagnostic or therapeutic procedures may be undertaken. While the endoscope body is advanced, the shapelock elongate body may be maintained in its rigidized state while held static relative to the stomach wall to provide a stable platform for endoscope advancement. Alternatively, the elongate body may be advanced distally in its rigidized or flexible state through the dilated gastric opening along with the endoscope body.  
      In another example for transgastrically accessing the peritoneal cavity, the shapelock elongate body may be placed directly against the stomach wall at a tissue contact region such that the elongate body provides some stability against the tissue surface during the procedure. The elongate body may be rigidized any time during the procedure relative to the stomach wall. If the elongate body is placed directly against a tissue contact region on the stomach wall over the gastric opening, the elongate body may be rigidized, as mentioned above, to provide for stability during the procedure.  
      Additionally and/or optionally, one or more retractable tissue anchors may he projected distally from within the end of elongate body and extended into and/or through tissue contact region to temporarily anchor the distal end of the elongate body to the region of stomach wall. The retractable tissue anchors may be configured as wires, hooks, barbs, corkscrews, etc., which are positioned within the walls of the elongate body for delivery through the patient and which may be urged distally to extend from the elongate body for engagement against or to the stomach wall. If the retractable tissue anchors are configured as wires, they may be comprised of a shape memory alloy such as Nitinol which remain in a straightened configuration but conform into a hooked configuration once free of any constraints.  
      The elongate body, either in its rigidized or flexible state, may then be advanced distally through the dilated gastric opening and further advanced into the peritoneal cavity, if so desired. Having an inflated dilation balloon retained within the shapelock lumen may minimize any transition step or region between the balloon and the elongate body to facilitate the passage of the elongate body through the dilated opening.  
      In yet another variation, the elongate body may be advanced into and through the gastric opening utilizing the endoscope, which may already be advanced through the gastric opening. With the elongate body positioned within the stomach and the steerable distal portion of the endoscope positioned externally of the stomach within the peritoneal cavity, the steerable distal portion may be retroflexed such that its distal end faces the exterior of the stomach wall. While maintaining the retroflexed configuration of the steerable distal portion, the body of the endoscope may be withdrawn proximally through the elongate body (or the elongate body may be pushed distally over the endoscope) until the stomach tissue surrounding the gastric opening is pushed over or onto a portion of the elongate body by the retroflexed steerable portion. Once a portion of the elongate body has been urged through the gastric opening, the surrounding tissue may optionally be anchored or otherwise adhered temporarily to the exterior of the elongate body through a variety of mechanisms, e.g., balloons, expandable mesh, retractable wires or barbs, etc., and the steerable distal portion may be straightened and further advanced into the peritoneal cavity to effect any number of diagnostic or therapeutic procedures. Alternatively, rather than using an endoscope, a specially adapted tissue retraction instrument may be utilized instead.  
      In yet another variation, the elongate body may be positioned adjacent to or against the gastric opening in a rigidized or flexible state. Once the elongate body has been desirably positioned, one or more deployable retraction members may be projected from the distal end of the elongate body. Such retraction members may be fabricated from a shape memory alloy, e.g., Nitinol, such that when positioned within its respective retraction member lumens, the retraction members are configured in a straightened shape for delivery. However, when first urged distally from the elongate body, the retraction members may be biased to initially converge towards a longitudinal axis of the elongate body to facilitate the initial insertion of the retraction members into and through the gastric opening.  
      The retraction members may be urged until the retained surrounding tissue is pushed over or upon the outer surface of the elongate body. Once the tissue around the gastric opening has been desirably pushed over the elongate body, the retraction members may be withdrawn back into the elongate body. Alternatively, the position of the elongate body and the retraction members may be maintained through the gastric opening and the endoscope may be advanced through the shapelock lumen and into the peritoneal cavity.  
      Another aspect of transgastric access may include adequate insufflation of the peritoneal cavity and/or stomach during advancement of an instrument through the stomach wall. When advancing a needle knife or ablation tool through the stomach wall, the physician may risk inadvertently cutting or piercing into any number of body structures, e.g., the peritoneal and/or abdominal wall, liver, aortic artery, etc., adjacent to the stomach through which a gastric opening is to be formed. Thus, one method for facilitating the safe incision through a stomach wall and into the peritoneal cavity may include the use of a flexible needle catheter or guidewire which may be deliverable through the endoscopic working lumen.  
      Flexible needle catheter or guidewire may include a hollow catheter or hollow guidewire having a needle body with a needle lumen defined therethrough attached to the distal end of the catheter or guidewire. Alternatively, the distal end of the needle catheter may be tapered into a piercing tip. The needle body may be advanced distally out of the elongate body and/or endoscope to pierce through the portion of the stomach wall to create the gastric opening. Once the needle body has just pierced through the stomach wall, it may be advanced slowly into the peritoneal cavity and a fluid or gas, e.g., water, saline, carbon dioxide, nitrogen, air, etc., may be pumped into the peritoneal cavity to insufflate the region, e.g., ≦15 mmHg, to lift adjacent body structures away from the external surface of the stomach wall. Accordingly, a pump located external to the patient body may be fluidly connected via a fluid line through the elongate body to the needle catheter or guidewire. Once the region surrounding the gastric opening has been sufficiently insufflated, a needle knife, ablation probe, or other instrument may be passed through the gastric opening or stomach wall without hitting any adjacent body structures.  
      Once a procedure has been completed within the peritoneal cavity, maintaining the location of the opening along the stomach wall may be desirable once the elongate body has been removed from the opening to facilitate the closure of the opening after the procedure has been completed within the peritoneal space.  
      One example is a marker assembly having an elongate flexible body with an inflatable balloon member reconfigurable between a low-profile advancement configuration and an expanded marking configuration. The inflatable member may have an expanded diameter which is larger than that of the elongate body and which is also larger than the opening. In use, prior to withdrawing the elongate body from the opening along the stomach wall, the elongate flexible body and expandable member may be advanced through a working lumen into the peritoneal space. Once the expandable member has been sufficiently advanced past the lumen opening, the expandable member may be expanded. With the mesh member in its expanded shape, the flexible member may optionally be withdrawn proximally until the mesh member is resting against the outer serosal tissue layer of stomach. The expanded profile prevents the pulling of the expandable member proximally back through the opening and may now serve as a marker for easily locating the position of opening.  
      With the marker in place distally of the opening, the expandable member may be used as a platform for facilitating the grasping and manipulating of the overlying tissue against the expandable member by the assembly. Once the tissue anchors have been deployed adjacent to the opening, the mesh member may be reconfigured into its low-profile configuration and withdrawn proximally back into the stomach through the opening via the flexible body. The tissue anchors may then be cinched or approximated towards one another to thereby close the opening.  
      Alternatively, the elongate body may be advanced into the stomach and positioned adjacent to a tissue region of interest through which the elongate body and/or tools are to he advanced through and into the peritoneal space. Prior to piercing and/or dilating an opening along the stomach wall, the tissue anchors may be deployed along the tissue region of interest. With the tissue area marked by the deployed tissue anchors, the lumen opening of the elongate body may be repositioned or advanced against and/or through the tissue region and an opening may be formed or dilated in the tissue adjacent or proximate to the anchors. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIGS. 1A and 1B  show a shape-lockable apparatus advanced endoluminally into a stomach with an endoscope placed therethrough and positioned for transgastric advancement into a peritoneal space of a patient.  
       FIGS. 2A  to  2 E show one example for passing an endoscope through an elongate shape-locking instrument transgastrically into the peritoneal space through a dilated gastric opening.  
       FIGS. 3A  to  3 E show another example for passing an endoscope and shapelock instrument into the peritoneal space by advancing both instruments through a gastric opening via a dilation balloon positioned within the shapelock instrument.  
       FIGS. 4A  to  4 D show yet another example for passing an endoscope and shapelock instrument transgastrically by urging tissue around the gastric opening over the shapelock instrument via a retroflexed endoscope.  
       FIGS. 5A  to  5 E show yet another example for transgastric access utilizing an expandable tissue urging device deployable through a working lumen of the shapelock instrument.  
       FIGS. 6A  to  6 F show yet another example for transgastric access utilizing a shapelock instrument having one or more reconfigurable members deployable from the shapelock instrument for pulling the instrument through the  
       FIGS. 7A  to  7 C show a flexible catheter or guidewire device having a tissue piercing tip adapted to be advanced through the tissue wall and into the peritoneal space for insufflating the space prior to or during endoscope advancement through the tissue wall.  
       FIGS. 8A and 8B  show the flexible catheter or guidewire device utilized to insufflate or re-insufflate the interior of the stomach.  
       FIG. 9  shows the elongate body as having been advanced trans-esophageally into the patient&#39;s stomach and desirably positioned for transgastric advancement through the stomach wall.  
       FIGS. 10A  to  10 D show an example of transgastric access through the stomach wall and into the peritoneal cavity facilitated by trans-abdominal access.  
       FIG. 11A  shows a portion of the stomach wall released or otherwise dislodged from a trocar leaving a gastrotomy or opening in the stomach wall.  
       FIG. 11B  shows an incising instrument passed through a simple abdominal incision from outside the patient body to assist in creating a gastrotomy or opening in the stomach wall.  
       FIGS. 12 and 13  illustrate other variations of creating incisions through the stomach wall by the insertion of incising instruments through the abdominal wall from outside the patient body.  
       FIGS. 14A  to  14 D show other examples of incising instruments which may be advanced through the abdominal wall either directly through an incision or through a trocar or other access port.  
       FIGS. 15A and 15B  show an example in which a dilation balloon assembly may be passed through an abdominal incision and into the gastric opening to dilate the opening for facilitating passage of instruments into the peritoneal cavity Erom within the stomach.  
       FIG. 16  shows an example of a laparoscope positioned through a trocar lumen to provide for laparoscopic imaging of a procedure within the peritoneal cavity.  
       FIG. 17  shows another example where visualization is provided via an endoscope once an abdominal incision has been closed.  
       FIGS. 18A and 18B  illustrate other access ports which may be utilized such as a Verres needle having a needle lumen inserted through the abdominal wall.  
       FIG. 19A  shows tissue anchors which have been deployed endoluminally from within the stomach to approximate the edges of the gastric opening.  
       FIGS. 19B  to  19 F show another example for obtaining transluminal access utilizing a tissue engaging instrument.  
       FIGS. 20A and 20B  show variations of tissue markers having an elongate flexible body with an inflatable member reconfigurable between a low profile advancement configuration and an expanded marking configuration.  
      FIGS.  21  to  24  illustrate one example for advancing an elongate body trans-esophageally into and through a stomach and deployment of a tissue marking assembly for marking or indicating an opening made within the tissue wall.  
       FIG. 25A  shows another variation for deploying an anchor assembly for marking or otherwise indicating a location along the stomach wall prior to piercing and/or advancing an elongate body therethrough.  
       FIGS. 25B and 25C  show an example where multiple pairs of tissue anchors may be deployed about the tissue region with their respective suture lengths leading from the tissue anchors proximally through the lumen or along the elongate body to outside the patient body.  
       FIGS. 26A  to  26 C show examples for deploying the anchor assemblies for marking or indicating a location of the opening along the gastric wall.  
       FIGS. 27A and 27B  show another example for closing an opening within the gastric wall by drawing a region of tissue having the opening within a snare positioned around an opening of the elongate body.  
       FIG. 28  shows yet another example of opposable substrates having a plurality of barbs therebetween for sandwiching a region of tissue having the opening. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      The present invention relates to apparatus and methods for endoluminal, transluminal procedures, including per-oral, transgastric and/or per-anal, transcolonic procedures. Access to regions within the body may be effected through a per-oral and transgastric approach where access to regions within a patient body, i.e., regions which are normally accessible through open or laparoscopic surgical procedures, may be accomplished through endoluminal methods and devices delivered endoluminally. For instance, access to a patient&#39;s peritoneal cavity may be accomplished entirely through endoluminal methods and devices via passage through an opening made in the stomach wall. Alternatively, endoluminal access may also be facilitated through a number of combined endoluminal and laparoscopic procedures. Various endoluminal and trans-abdominal access methods and devices are shown in further detail in U.S. patent application Ser. No. 11/238,279, filed Sep. 28, 2005, which is incorporated herein by reference in its entirety.  
      Examples of endoluminal methods and instruments are first described below. With reference to  FIGS. 1A and 1B , a shape-lockable assembly  10  is shown having been advanced per-orally, through the esophagus E, and into the stomach S of a patient. Shape-lockable assembly  10  may comprise, in part, a flexible and elongate shape-locking body  12  which may utilize a plurality of locking links which enable the elongate body  12  to transition between a flexible state and a rigidized or shape-locked configuration. Details of such a shape-lockable body may be seen in further detail in U.S. Pat. Nos. 6,783,491; 6,790,173; and 6,837,847, each of which is incorporated herein by reference in its entirety.  
      Additionally, the elongate body  12  may also incorporate additional features that may enable any number of therapeutic procedures to be performed endoluminally. An elongate body  12  may be accordingly sized to be introduced per-orally. However, the elongate body may also be configured in any number of sizes, for instance, for advancement within and for procedures in the lower gastrointestinal tract, such as the colon.  
      The assembly, in one variation, may have several separate controllable bending sections along its length to enable any number of configurations for the elongate body  12 . For instance, in one variation, elongate body  12  may further comprise a bending section located distal of the elongate body  12 ; the bending section may be configured to bend in a controlled manner within a first and/or second plane relative to the elongate body  12 . In yet another variation, the elongate body  12  may further comprise another bending section located distal of the first bending section. In this variation, the bending section may be configured to articulate in multiple planes, e.g., 4-way articulation, relative to the first bending section and elongate body  12 . In a further variation, a third bending section may also be utilized along the length of the device.  
      In yet another variation, each of the bending sections and the elongate body may be configured to lock or shape-lock its configuration into a rigid set shape once the articulation has been desirably configured. An example of such an apparatus having multiple bending sections which may be selectively rigidized between a flexible configuration and a shape-locked configuration may be seen in further detail in U.S. Pat. Pubs. 2004/0138525 A1; 2004/0138529 A1; 2004/0249367 A1; and 2005/0065397 A1, each of which is incorporated herein by reference in its entirety.  
      As the bending sections may be articulated in any number of configurations via control wires routed through the elongate body, the assembly  10  may be actively steered to reach all areas of the stomach. The bending features may be controlled via a handle  14  attached to a proximal end of elongate body  12  and a rigidization actuation lever  16  may be manipulated to actuate the transition between rigid and flexible states of elongate body  12 . Handle  14  may also define an entry port  18  therethrough which allows for passage of any number of endoluminal instruments through handle  14  from outside the patient body and into at least one working lumen  20  defined through the length of elongate body  12  for passage into the patient body.  
      Once a desired position is achieved within a patient body, e.g., within stomach S, the elongate body  12  may be locked or rigidized in place, as shown in  FIG. 1A . An endoscope  22 , controllable via endoscope handle  26  attached thereto, may be passed through shapelock assembly handle  14  for insertion into the patient body through lumen  20 . Alternatively, endoscope  22  may be advanced endoluminally through the patient simultaneously along with elongate body  12 . In either case, once elongate body  12  has been desirably positioned and rigidized near or against an interior region of the stomach S, the endoscope body  24  and/or the shapelock elongate body  12  may be pierced through or otherwise passed through gastric opening  28  formed through the stomach wall and advanced through or into the peritoneal cavity PC of the patient, as shown in  FIG. 1B . Once endoscope  24  and/or elongate body  12  are positioned within the peritoneal cavity PC, any number of diagnostic or therapeutic procedures may be performed.  
      Various other apparatus and methods for transgastric advancement through a gastric wall for access into the peritoneal space are disclosed in greater detail in U.S. patent application Ser. No. 10/918,217 filed August 11, 2004, which is incorporated herein by reference in its entirety.  
      In passing endoscope  24  through the stomach wall SW, a number of different methods and tools may be employed. For instance,  FIGS. 2A  to  2 E show one example for passing endoscope  24  through the elongate shape-locking body  12  transgastrically into the peritoneal cavity PC through dilated gastric opening  28 . Once elongate body  12  has been desirably positioned adjacent to or near a region of stomach wall SW, an ablation probe or needle knife  34  may be advanced through endoscope lumen  32  into proximity with stomach wall SW, as shown in  FIG. 2A . Visualization may be provided by imaging lumen  30  of endoscope  24 .  
      The probe or needle knife  34  may be actuated to pierce or cut through stomach wall SW at the tissue region of interest to create a gastric opening  28  into the peritoneal cavity PC. Once a gastric opening  28  of sufficient size, i.e., at least sufficiently large enough to pass a guidewire or probe therethrough, has been created in stomach wall SW, needle knife  34  may be removed from endoscopic lumen  32  and a conventional guidewire  36  may be advanced therethrough until guidewire  36  is passed at least partially within peritoneal cavity PC, as shown in  FIG. 2B .  
      With guidewire  36  in place, a dilation balloon  38  having an expanded diameter of, e.g., 18 or 20 mm (or eater), may be passed in its unexpanded profile over guidewire  36  through endoscope lumen  32  until dilation balloon  38  is positioned within gastric opening  28 , as shown in  FIG. 2C . Dilation balloon  38  may then be expanded to thereby dilate gastric opening  28  to a diameter sufficient to allow for passage of at least endoscope body  24 . Once gastric opening  28  has been desirably dilated, as shown in  FIG. 2D , the balloon  38  may be deflated and withdrawn proximally through endoscope lumen  32 . Guidewire  36  may also be withdrawn proximally, if so desired. Endoscope body  24  may then be advanced distally through the dilated gastric opening  28  for entry into the peritoneal cavity PC, as shown in  FIG. 2E , where any number of diagnostic or therapeutic procedures maybe undertaken. While endoscope body  24  is advanced distally through gastric opening  28 , shapelock elongate body  12  may be maintained in its rigidized state while held static relative to stomach wall SW to provide a stable platform for endoscope advancement. Alternatively, elongate body  12  may be advanced distally in its rigidized or flexible state through dilated gastric opening  28  along with endoscope body  24 .  
      In another example for transgastrically accessing the peritoneal cavity PC,  FIGS. 3A  to  3 E illustrate passing an endoscope and shapelock instrument into the peritoneal cavity PC by advancing both instruments through a dilated gastric opening  28  via dilation balloon  38  positioned within the shapelock lumen  20 . In use, once gastric opening  28  has been formed, as described above, shapelock elongate body  12  may be advanced and positioned adjacent to or directly against stomach wall SW over gastric opening  28  and guidewire  36  may be passed through the endoscope working lumen  32 , through gastric opening  28 , and into peritoneal cavity PC, as shown in  FIG. 3A . Elongate body  12  may be optionally locked into its rigidized state prior to, during, or after positioning elongate body  12  relative to the stomach wall. Shapelock elongate body  12  may be placed directly against the stomach wall SW, as mentioned, along a tissue contact region  40  such that elongate body  12  may provide some stability against the tissue surface during the procedure. The elongate body  12  may be rigidized any time during the procedure relative to the stomach wall SW although elongate body  12  is preferably, but not necessarily, rigidized prior to advancing the dilation balloon through gastric opening  28 , as described below.  
      If elongate body  12  is placed directly against a tissue contact region  40  on stomach wall SW over gastric opening  28 , elongate body  12  may be rigidized, as mentioned above, to provide for stability during the procedure. Additionally and/or optionally, one or more retractable tissue anchors  42  may be projected distally from within the end of elongate body  12  and extended into and/or through tissue contact region  40  to temporarily anchor the distal end of elongate body  12  to the region of stomach wall SW. Retractable tissue anchors  42  may be configured as wires, hooks, barbs, corkscrews, etc., which are positioned within the walls of elongate body  12  for delivery through the patient and which may be urged distally to extend from elongate body  12  for engagement against or to the stomach wall SW. If retractable tissue anchors  42  are configured as wires, they maybe comprised of a shape memory alloy such as Nitinol which remain in a straightened configuration but conform into a hooked configuration once free of any constraints, as shown in  FIG. 3B .  
      Regardless of whether retractable tissue anchors  42  are utilized, once guidewire  36  has been passed through gastric opening  28  and into peritoneal cavity PC, dilation balloon  38  may be passed through endoscope lumen  32  over guidewire  36  until balloon  38  is partially through gastric opening  28  and also partially within the shapelock lumen  20 . Dilation balloon  38 , while still retained at least partially within shapelock lumen  20 , may then be inflated or expanded to dilate gastric opening  28 , as shown in  FIG. 3C .  
      Elongate body  12 , either in its rigidized or flexible state, may then be advanced distally through the dilated gastric opening  28 , as shown in  FIG. 3D , and further advanced into the peritoneal cavity PC, if so desired. Having an inflated dilation balloon  38  retained within shapelock lumen  20  may minimize any transition step or region  44  between balloon  38  and elongate body  12  to facilitate the passage of elongate body  12  through dilated gastric opening  28 . Once elongate body  12  is passed through gastric opening  28 , dilation balloon  38  may be deflated and withdrawn and endoscope  24  may be advanced into peritoneal cavity PC, as shown in  FIG. 3E , where endoscope  24  may then be directed via its steerable distal portion  46  to perform any number of diagnostic or therapeutic procedures within the peritoneal cavity PC.  
      In yet another variation, elongate body  12  may be advanced into and through gastric opening  28  utilizing the endoscope  24 , which may already be advanced through gastric opening  28 , as described above and as shown in  FIG. 4A . With elongate body  12  positioned within the stomach S and the steerable distal portion  46  of endoscope  24  positioned externally of the stomach S within the peritoneal cavity PC, steerable distal portion  46  may be retroflexed such that its distal end faces the exterior of the stomach wall SW, as shown in  FIG. 4B .  
      While maintaining the retroflexed configuration of steerable distal portion  46 , the body of endoscope  24  may be withdrawn proximally through elongate body  12  (or elongate body  12  may be pushed distally over endoscope  24 ) until the stomach tissue surrounding gastric opening  28  is pushed over or onto a portion of elongate body  12  by the retroflexed steerable portion  46 , as shown in  FIG. 4C . Once a portion of elongate body  12  has been urged through gastric opening  28 , the surrounding tissue may optionally be anchored or otherwise adhered temporarily to the exterior of elongate body  12  through a variety of mechanisms, e.g., balloons, expandable mesh, retractable wires or barbs, etc., and steerable distal portion  46  may be straightened and further advanced into the peritoneal cavity PC to effect any number of diagnostic or therapeutic procedures.  
      In yet another variation for acquiring access to the peritoneal cavity PC, once gastric opening  28  has been formed, a tissue retraction instrument  50  may be passed through shapelock lumen  20  and through an un-dilated gastric opening  28  to pull the tissue surrounding gastric opening  28  over or onto elongate body  12 . An example of such a tissue retraction instrument  50  is shown in  FIG. 5A , which is seen having been advanced through gastric opening  28  with deployable retraction arm members  54  in a low-profile configuration where one or more arm members  54 , e.g., at least two arm members, are retracted with respect to a flexible retraction shaft  52 .  
      Retraction arm members  54  may be configured into a curved, arcuate, or otherwise angled member such that when pivoted or rotated about connection  56  at a distal end of retraction shaft  52 , the distal ends  58  of retraction arm members  54  are curved or angled proximally towards elongate body  12  and a deployed diameter of retraction arm members  54  is equal to greater than a diameter of elongate body  12 , as shown in  FIG. 5B . Retraction arm members  54  may be fabricated from any number of materials which are biocompatible, e.g., stainless steel, Nitinol, high-density polymers, etc.  
      Once retraction arm members  54  are deployed or expanded, as in  FIG. 5B , flexible retraction shaft  52  may be pulled proximally relative to elongate body  12  until the tissue surrounding gastric opening  28  is pulled over or onto elongate body  12  by the deployed distal ends  58  of retraction members  54 , as shown in  FIG. 5C . Alternatively, elongate body  12  may be pushed distally relative to deployed retraction members  54  until the surrounding tissue is pulled or pushed thereupon. Once the elongate body  12  is pushed through gastric opening  28 , retraction shaft  52  may be pushed distally and retraction arms  54  reconfigured into its low-profile for proximal withdrawal through elongate body  12 , as shown in  FIG. 5D . Once retraction instrument  50  has been withdrawn, endoscope  24  may be advanced through elongate body  12  and further advanced into the peritoneal cavity PC, as shown in  FIG. 5E .  
      In yet another variation for accessing the peritoneal cavity PC from within the stomach S, elongate body  12  may be positioned adjacent to or against gastric opening  28  it a rigidized or flexible state, as described above and as shown in  FIG. 6A . Once elongate body  12  has been desirably positioned, one or more deployable retraction members  60  may be projected from the distal end of elongate body  12 . Retraction members  60  may be fabricated from a shape memory alloy, e.g., Nitinol, such that when positioned within its respective retraction member lumens  62 , retraction members  60  are configured in a straightened shape for delivery. However, when first urged distally from elongate body  12 , retraction members  60  may be biased to initially converge towards a longitudinal axis of the elongate body  12  to facilitate the initial insertion of the retraction members  60  into and through gastric opening  28 , as shown in  FIG. 6B .  
      Retraction members  60  may be positioned about a circumference of the distal end of elongate body  12  in an asymmetric or uniform spacing. Moreover, any number of retraction members  60  may be utilized, e.g., two, three, four, or more as practicable, although four are shown in the end view of the example of  FIG. 6C . As retraction members  60  are urged further distally from elongate body  12 , they may be adapted to then reconfigure into a radially hooked or angled configuration extending away from the longitudinal axis of elongate body  12 . As retraction members  60  begin to extend radially and outwardly, they may contact the tissue surrounding gastric opening  28  and begin dilating the opening  28 , as shown in  FIG. 6D . The farther retraction members  60  are urged distally, the greater the hooked or angled configuration.  
      Accordingly, retraction members  60  may be urged until the retained surrounding tissue is pushed over or upon the outer surface of elongate body  12 , as shown in  FIG. 6E . Once the tissue around gastric opening  28  has been desirably pushed over elongate body  12 , retraction members  60  may be withdrawn back into elongate body  12 , which may then be farther advanced into the peritoneal cavity PC. Alternatively, the position of elongate body  12  and retraction members  60  may be maintained through gastric opening  28  and the endoscope  24  may be advanced through shapelock lumen  20  and into the peritoneal cavity PC, as shown in  FIG. 6F .  
      Another aspect of transgastric access may include adequate insufflation of the peritoneal cavity PC and/or stomach S during advancement of an instrument through the stomach wall SW. When advancing a needle knife or ablation tool through the stomach wall SW, the physician may risk inadvertently cutting or piercing into any number of body structures, e.g., the peritoneal and/or abdominal wall, liver, aortic artery, etc., adjacent to the stomach through which a gastric opening  28  is to be formed. Thus, one method for facilitating the safe incision through a stomach wall SW and into the peritoneal cavity PC may include the use of a flexible needle catheter or guidewire  70  which may be deliverable through the endoscopic working lumen  32 , as shown in  FIG. 7A .  
      Flexible needle catheter or guidewire  70  may include a hollow catheter or hollow guidewire having a needle body  72  with a needle lumen  74  defined therethrough attached to the distal end of the catheter or guidewire. Alternatively, the distal end of the needle catheter  70  may be tapered into a piercing tip. As shown in  FIG. 7B , the needle body  72  may be advanced distally out of elongate body  12  and/or endoscope  24  to pierce through the portion of the stomach wall SW to create gastric opening  28 . Once needle body  72  has just pierced through the stomach wall SW, it may be advanced slowly into the peritoneal cavity PC and a fluid or gas  76 , e.g., water, saline, carbon dioxide, nitrogen, air, etc., may be pumped into the peritoneal cavity PC to insufflate the region, e.g., ≦15 mmHg and as shown in  FIG. 7C , to lift adjacent body structures away from the external surface of the stomach wall SW. Accordingly, a pump  78  located external to the patient body may be fluidly connected via fluid line  80  through elongate body  12  to needle catheter or guidewire  70 . Once the region surrounding gastric opening  28  has been sufficiently insufflated, a needle knife, ablation probe, or other instrument may be passed through gastric opening  28  or stomach wall SW without hitting any adjacent body structures.  
      Additionally or alternatively, needle catheter or guidewire  70  may be utilized to insufflate or re-insufflate the stomach S after a procedure has been performed within the peritoneal cavity PC, as shown in  FIG. 8A . Once elongate body  12  and/or endoscope  24  are to be withdrawn from the peritoneal cavity PC, the stomach S may be in a deflated condition because of insufflation gas escaping through gastric opening  28  into the peritoneal cavity PC or back through the esophagus. Accordingly, once endoscope  24  has been withdrawn back into the stomach S, needle catheter or guidewire  70  may be deployed within the stomach S to insufflate or re-insufflate the stomach S so that the gastric opening  28  may be clearly visible for then closing the opening  28 .  
      To facilitate the re-insufflation of the stomach S, gastric opening  28  may alternatively be sealed or plugged temporarily through a variety of apparatus, as described below in further detail. One example is shown in  FIG. 8B  which shows an inflatable balloon  84  advanced via inflation shaft  82  through an additional endoscopic lumen  86 . Balloon  84  may be delivered via endoscopic lumen  86  in a deflated condition and passed through gastric opening  28 . Balloon  84  may then be inflated to a size larger than gastric opening  28  and pulled against the exterior surface of stomach wall SW to plug or seal gastric opening  28 . With opening  28  sealed temporarily, needle catheter or guidewire  70  may be used to insufflate the interior of the stomach S. After the stomach S has been sufficiently insufflated, i.e., insufflated such that visualization of the interior stomach wall SW is possible, the gastric opening  28  may be sealed and balloon  84  may be deflated and withdrawn proximally through gastric opening  28  before it is entirely sealed from the peritoneal cavity PC.  
      In addition to endoluminal methods and devices, laparoscopic, trans-abdominal, and/or other percutaneous approaches and procedures may be utilized in combination with any of the above-described endoluminal approaches to facilitate intra-abdominal access within a patient body PT. Turning now to  FIG. 9 , elongate body  12  may be seen as having been advanced endoluminally, e.g., through the patient&#39;s mouth and esophagus E and into stomach S, until the opening or working lumen  20  has been desirably positioned within stomach S for transgastric advancement through the stomach wall.  
      As described above, an incision or gastrotomy may be made within the stomach wall and an endoscope, elongate body, or other instrument may be passed through or along elongate body  12 , through the gastrotomy, and into the peritoneal cavity of the patient body PT. An instrument for making the incision and/or dilating the opening may be advanced through or along elongate body  12  for an endoluminal transgastric approach. Other variations may include utilizing trans-abdominal procedures in combination with a transgastric approach for obtaining intra-abdominal access.  
      As shown in  FIGS. 10A  to  10 D, transgastric access may be facilitated utilizing trans-abdominal procedures similar to those for placing gastrotomy tubes in a patient. A portion of the abdominal wall AW adjacent to the stomach S is illustrated in  FIG. 10A  with elongate body  12  and, e.g., endoscope  24 , positioned within stomach S. Endoscope  24  may provide lighting via lumen  30  to illuminate the interior of stomach S and may also optionally provide insufflation through endoscope  24  or through another lumen. With stomach wall SW adjacent to a portion of abdominal wall AW, an access port such as trocar  90  with obturator  92  positioned through trocar lumen  94  may be advanced from outside the patient body and through abdominal wall AW, peritoneal cavity PC, and through stomach wall SW into stomach S, as shown in  FIG. 10B .  
      Obturator  92  may be provided with a piercing tip  96  to facilitate its passage through the tissue into stomach S. Once the access port or trocar  90  has been pierced through stomach S, obturator  92  may be removed such that trocar lumen  94  is clear to provide unobstructed access. Trocar  90  may include seals or gaskets therewithin to maintain insufflation patency. The light provided by lumen  30  transmitted through abdominal wall AW may be generally seen from within stomach S and externally of the patient body. During placement of the access port, the light provided through lumen  30  may be utilized as an indicator to the physician that access to stomach S is clear of any intervening organs or tissue body and the trocar  90  may be advanced through the abdominal wall without inadvertently injuring surrounding tissue.  
      With trocar  90  in place, a guidewire  36  may be optionally advanced into stomach S through lumen  32  of endoscope  24  or through another working lumen defined through or along elongate body  12 . Prior to, during, or after guidewire  36  has been positioned within stomach S, a snare or other retrieval device  98  may also be advanced through trocar lumen  94  from outside the patient body and into stomach S where the snare or, e.g., loop  100 , may be manipulated to grasp, snare, or otherwise hold guidewire  36 , as shown in  FIG. 10C . Retrieval device  98  may be then withdrawn proximally through trocar lumen  94  while pulling guidewire  36  from within stomach S to outside the patient body, as shown in  FIG. 10D .  
      With guidewire  36  routed from the patient&#39;s mouth, through stomach S, and back outside the patient body through stomach wall SW and abdominal wall AW, any number of instruments, e.g., dilation instruments for dilating the opening in the stomach wall SW, may be guided into: the stomach S or into peritoneal cavity PC via trocar lumen  94  along guidewire  36 . Alternatively, guidewire  36  may be omitted entirely so that once trocar  90  has been advanced through the abdominal wall AW and stomach wall SW, trocar  90  may be proximally withdrawn until stomach wall SW is released or otherwise dislodged from trocar  90  leaving gastrotomy or opening  102 , as shown in  FIG. 11A .  
      Additionally or alternatively, a grasping instrument may be endoluminally advanced through or along elongate body  12  or endoscope  24  and articulated to pull stomach wall SW free from trocar  90 . Elongate body  12  may be rigidized during such a procedure to provide for instrument stability. Moreover, the insufflation in stomach S, if utilized, may be reduced at least temporarily such that the stomach wall SW is relaxed and not taut. Once stomach wall SW is free from trocar  90 , elongate body  12  and/or endoscope  24 , or any other endoluminally advanced instrument, may be advanced through opening  102 , as described above. Moreover, additional instruments, e.g., laparoscopic instruments, may be passed through trocar  90  for assisting passage of elongate body  12 , endoscope  24 , or other instruments through opening  102 . Other instruments may be passed through trocar  90  for facilitating procedures within the patient&#39;s peritoneal cavity PC and/or for closing the opening  102  (or multiple openings) from outside stomach S once a procedure is completed and any endoluminal instruments have been withdrawn proximally through opening  102 .  
      As shown in  FIG. 11B , rather than utilizing a trocar  90  or other access port for creating openings within the stomach wall SW through the patient&#39;s abdominal wall AW, a simple incision  104  may be created in the abdominal wall AW of the patient and an incising instrument  106 , such as an ablation probe, electrocautery catheter, needle knife, scissors, etc., may be passed through the incision from outside the patient body and directed towards an exterior surface of stomach wall SW to cut, ablate, or otherwise create an opening therethrough to provide transgastric access for endoluminally delivered instruments. This eliminates the need for endoluminal delivery and manipulation of any elongate incising instrument through or along elongate body  12  or endoscope  24 . Once the incision in stomach wall SW has been made, instrument  106  may he withdrawn from the patient body and incision  104  in abdominal wall AW may be closed before, during, or after completion of an endoluminal procedure within the peritoneal cavity PC.  
       FIGS. 12 and 13  illustrate other variations of creating incisions through the stomach wall SW by the insertion of incising instruments through the abdominal wall AW from outside the patient body. In this case, trocar  90  or other access ports may be utilized rather than passing tools directly through an incision in the abdominal wall AW.  FIG. 12  illustrates an example in which an ablation probe  110 , e.g., electrocautery catheter, needle knife, etc., having an energizable probe tip  112  may be passed through trocar lumen  94  to create an incision  114  through stomach wall SW from the exterior surface. Lumen  30  may be used to illuminate a portion of the stomach wall SW from within the stomach S to act as a guide for locating where incision  114  may be placed along stomach wall SW.  
      Moreover, endoscope  24  may also be used to provide endoluminal visualization while incision  114  is made. Alternatively, a laparoscope or other visualization instrument may be provided through trocar  90  or another abdominal incision to provide additional or alternative visualization through the abdominal wall AW.  FIG. 13  shows a similar variation utilizing a mechanical incising instrument  116  passed through trocar  90  where the incising instrument  116  has an articulatable cutting end effector  118 , e.g., laparoscopic scissors.  
      Other examples of incising instruments which may be advanced through the abdominal wall AW either directly through an incision or through a trocar  90  or other access port are shown in  FIGS. 14A  to  14 D.  FIG. 14A  illustrates a pair of scissors, such as a pair of Potts-Smith scissors  120  having cutting jaws  122 .  FIG. 14B  shows a needle knife  124  while  FIG. 14C  illustrates an RF probe  126  and  FIG. 14D  illustrates a laser probe  128 . These instruments, as well as other incising instruments disclosed herein, are not intended to be limiting but are shown as examples of types of incising tools which may be utilized to effectuate transgastric incisions.  
      Once an incision has been made in the stomach wall SW, it may be desirable to dilate the opening prior to passing the endoscope  24  or elongate body  12  through the stomach wall SW and into the peritoneal cavity PC. An example for endoluminally dilating the opening is described above in  FIGS. 2C and 2D  utilizing a dilation balloon delivered trans-esophageally. In this example, a dilation balloon assembly  130  may be passed through trocar lumen  94  (or directly through an incision in the abdominal wall AW) such that a dilation balloon in its deflated state  132  is positioned within an undilated opening  134 , as shown in  FIG. 15A .  
      Placement of balloon  132  within opening  134  may be accomplished under visualization provided by endoscope  24  or alternatively through a laparoscope positioned within another opening through the abdominal wall AW, if so desired. Additionally, dilation balloon assembly  130  may be passed over a guidewire  36  (if optionally utilized and as shown above in  FIG. 10D ) to facilitate the positioning of balloon assembly  130  within the undilated opening  134 . Once balloon  134  is in position within opening  134 , the balloon may be expanded to its inflated state  132 ′ to thereby dilate opening  134 ′, as shown in  FIG. 15B .  
      As mentioned above, visualization of the procedure may be provided or facilitated through the abdominal opening by placing an imager through the abdominal wall AW proximate to the gastric opening. For example, as shown in  FIG. 16 , laparoscope  140  may be positioned through trocar lumen  94  to provide for laparoscopic imaging of the procedure. The images provided from laparoscope  140  may be utilized alone or in combination with the images provided through endoscope  24 . Alternatively, once the gastric opening has been made, any instruments or trocars  90  may be removed from the abdominal incision  142 , which may then be closed by any variety of wound closure fasteners  144 , e.g., sutures, staples, clips, etc. In this case, visualization is provided by the endoscope  24 , as shown in  FIG. 17 .  
      Trocar  90  may be utilized as an access port or instruments may be simply passed from outside the patient body and through abdominal incisions to provide access to the exterior of the stomach wall SW. Other access ports which may be utilized may include hollow needles, e.g., Verres needle  150  having a needle lumen  152 , which may be inserted through the abdominal wall AW to provide for prior peritoneal insufflation, as shown in  FIG. 18A . Verres needle  150  may be inserted before inserting a trocar through the abdominal wall AW or prior to passing elongate body  12 , endoscope  24 , or any other instruments through the gastric opening  134 ′ and into the peritoneal cavity PC, as shown in  FIG. 18B . Additionally, once Verres needle  150  has been placed through the abdominal wall AW, an incising probe, energized and/or tapered, may be inserted directly through the needle lumen  152  for creating an incision from the stomach exterior and through the stomach wall SW, which may be dilated endoluminally from within the stomach S utilizing any of the methods and devices described above.  
      After a procedure has been accomplished within the peritoneal cavity PC, the devices and/or instruments may be withdrawn proximally through the gastric opening  102 . Opening  102  may then be closed to seal stomach wall SW utilizing, e.g., tissue anchors  160 ,  162  slidably connected via a connecting member such as suture  164 . Tissue anchors  160 ,  162  may be deployed endoluminally from within stomach S to approximate the edges of opening  102 , as shown in  FIG. 19A  and as described in further detail below.  
      Another example for obtaining transluminal access into the peritoneal cavity PC may be seen in the  FIGS. 19B  to  19 F, which shows transgastric access utilizing an elongate tissue engaging instrument. An initial gastric opening  102  may be made utilizing any of the methods and tools described herein and the distal end of the elongate body  12  may be positioned proximate to the opening  102 . If the region immediately outside the opening  102  within the peritoneal cavity PC appears clear and unobstructed, a corkscrew-type helical tissue engager  166  positioned upon a flexible elongate member  168  may be passed through the elongate body  12  and through the opening  102 , as shown in  FIG. 19B . Other types of tissue engagement instruments such as tissue graspers may also be utilized.  
      With the elongate body  12  still within the stomach S, helical tissue engager  166  may be directed against the peritoneal wall of the abdomen. Contact between the tissue engager  166  and the abdominal wall AW can be verified by placing a fingertip against the outside of the abdominal wall AW and feeling for the tissue engager  166  beneath the tissue. The helical tissue engager  166  is preferably anchored into the abdominal wall AW at a position which is directly proximate to the opening  102  or in a caudal position relative to the patient body such that excessive stretching of the stomach wall SW may be minimized during passage of the elongate body through the opening  102 . Prior to or during anchoring of the helical engager  166 , the elongate body  12  may be optionally transitioned into its rigid configuration to provide a stable platform.  
      Once properly positioned, the elongate member  168  may be torqued from its proximal end outside the patient body to rotate the helical engager  166  into a secure engagement with the tissue, as shown in  FIG. 19C . Once the helical engager  166  has been securely anchored within the tissue, the elongate member  168  may be used as a guidewire to direct the elongate body  12  into the peritoneal cavity PC by pulling on the elongate member  168  proximally while pushing the elongate body  12  distally past the opening  102 , as shown in  FIG. 19D . If the elongate body  12  were rigidized during anchoring of the helical engager  166 , it may be simply transitioned into a flexible state prior to or while advancing the elongate body  12  through the opening  102 .  
      With the distal end of the elongate body  12  passed through opening  102  and positioned within the peritoneal cavity PC, the helical engager  166  may be disengaged, as shown in  FIG. 19E , and the elongate member  168  may be removed entirely from the elongate body  12 , if desired. Once within the peritoneal cavity PC, the elongate body  12  may be advanced and directed to accomplish a procedure, as shown in  FIG. 19F .  
      Turning now to closure of wounds and openings, such as gastrotomies, utilizing endoluminal instruments and methods, various examples are described below. Although the examples and illustrations below describe the use of a shape-lockable or rigidizable body, the methods and instruments described below may also be utilized with flexible endoscopes for wound closure.  
      Once gastric opening  28  is made in the gastric tissue wall, as shown above, the opening  28  may be closed through a variety of endoluminal apparatus and methods. However, maintaining the location of the opening  28  along the stomach wall may be desirable once the elongate body  12  has been removed from the opening  28  to facilitate the closure of the opening  28  after the procedure has been completed within the peritoneal space. As shown in  FIGS. 20A and 20B , variations of tissue markers are illustrated.  FIG. 20A  shows one example of marker assembly  170  having an elongate flexible body  172  with an inflatable balloon member  174  reconfigurable between a low-profile advancement configuration and an expanded marking configuration. The inflatable member may have an expanded diameter which is larger than that of the elongate body  12  and which is also larger than the opening  28 .  FIG. 20B  likewise shows another example of marker assembly  180  having elongate flexible body  182  with a reconfigurable mesh member  184  which may also be reconfigured from a low-profile advancement configuration to an expanded tissue marking configuration. Although these examples illustrate balloon and mesh variations, these are intended to be merely illustrative and are not intended to be limiting. Other examples of expandable members as generally known within the art are intended to be within the scope of this disclosure.  
      In use, as shown in  FIG. 21 , prior to withdrawing elongate body  12  from opening  28  along the stomach wall, elongate flexible body  182  and, e.g., mesh member  184 , may be advanced through shapelock lumen  20  into the peritoneal cavity PC. Once mesh member  184  has been sufficiently advanced past the lumen opening, mesh member  184  may be expanded. With mesh member  184  now in its expanded shape, flexible member  182  may optionally be withdrawn proximally until mesh member  184  is resting against the outer serosal tissue layer of stomach S, as shown in  FIG. 22 . The expanded profile prevents the pulling of mesh member  184  proximally back through opening  28  and may now serve as a marker for easily locating the position of opening  28 .  
      Once opening  28  has been marked with mesh member  184  and flexible body  182  extending therethrough, a tissue approximation and securement assembly  190  may be advanced through elongate body  12  and into the stomach S, as shown in  FIG. 23 . Assembly  190  may be advanced optionally through the esophagus E as a separate instrument externally of elongate body  12 , if so desired. Tissue approximation and securement assembly  190  may include a flexible body  192  and a tissue manipulation and securement end effector  194  for grasping, manipulating, and/or otherwise securing regions of tissue. Examples of assembly  190  may be seen in further detail in U.S. patent application Ser. No. 10/955,245 filed Sep. 29, 2004 and Ser. No. 11/070,863 filed Mar. 1, 2005, each of which is incorporated herein by reference in its entirety.  
      Using assembly  190 , opening  28  may be closed and secured by deploying one or more tissue anchors  200 ,  202  connected via a length of suture  204 , as mentioned above. Anchors  200 ,  202  may be configured to be cinched uni-directionally towards one another as disclosed in further detail in U.S. patent application Ser. No. 10/840,950 filed May 7, 2004, which is incorporated herein by reference in its entirety. Further details are also disclosed for deploying tissue anchors and closing openings  28  along the gastric tissue in U.S. patent application Ser. No. 10/918,217 filed Aug. 11, 2004, which is incorporated above by reference.  
      With the marker in place distally of opening  28 , mesh member  184  may he used as a platform for facilitating the grasping and manipulating of the overlying tissue against mesh member  184  by assembly  190 . Once tissue anchors  200 ,  202  have been deployed adjacent to opening  28 , mesh member  184  may be reconfigured into its low-profile configuration and withdrawn proximally back into the stomach S through opening  28  via flexible body  182 . The tissue anchors may then be cinched or approximated towards one another to thereby close the opening  28 , as shown in  FIG. 24 . Elongate body  12  may then be withdrawn from stomach S entirely or further procedures may be affected.  
      In an alternative method, elongate body  12  may be advanced into the stomach S and positioned adjacent to a tissue region of interest T through which the elongate body  12  and/or tools are to be advanced through and into the peritoneal cavity. Prior to piercing and/or dilating an opening along the stomach wall, tissue anchors  200 ,  202  interconnected via suture  204  may be deployed along the tissue region of interest T utilizing assembly  190 , as described above, and as shown in  FIG. 25A . With the tissue area marked by the deployed tissue anchors  200 ,  202 , the lumen opening  20  of elongate body  12  may be repositioned or advanced against and/or through the tissue region T and an opening  28  may be formed or dilated in the tissue adjacent or proximate to anchors  200 ,  202 .  
      In an alternative variation for cinching the tissue anchors,  FIG. 25B  shows an example where, e.g., multiple pairs of tissue anchors  200 ,  202 ,  206 ,  208 , may be deployed about the tissue region T with their respective suture lengths  209  leading from the tissue anchors proximally through lumen  20  or along elongate body  12  to outside the patient body. With the proximal ends of suture lengths  209  outside the patient&#39;s body, the suture  209  may be tensioned proximally while elongate body  12 , in its rigidized state, may be urged distally against the tissue region. This counteracting force can enable the tissue anchors  200 ,  202 ,  206 ,  208  to cinch towards one another to close any gastric openings by localizing forces between the distal end of elongate body  12  against the stomach tissue and the tissue anchors  200 ,  202 ,  206 ,  208 . Once the tissue has been desirably approximated between the respective tissue anchors  200 ,  202 ,  206 ,  208 , the suture may be cut  209 ′ to release the anchors and the elongate body  12  may be removed from the stomach S, as shown in  FIG. 25C .  
      After any procedures within the peritoneal space have been completed, any instruments and elongate body  12  may be withdrawn proximally through the opening  28 , as mentioned. The opening  28  may be subsequently located within the stomach S by the position of anchors  200 ,  202  in the tissue and the opening  28  may then be easily closed by simply approximating the pre-deployed anchors towards one another.  
       FIGS. 26A and 26B  show two examples for the pre-deployment of tissue anchors  200 ,  202  relative to opening  28 , which may be formed prior to or after deployment of the anchors within the tissue region T. In the example shown in  FIG. 26A , a first set of tissue anchors  200 ,  202  connected via suture  204  may be deployed in the tissue region T and a second set of tissue anchors  200 ′,  202 ′ connected via suture  204 ′ may also be deployed in the tissue region T at a distance from the first set of tissue anchors  200 ,  202 . If opening  28  were made prior to deployment of the tissue anchors, the first and second sets of anchors may be deployed adjacently on either side of opening  28 . If opening  28  were to be made after deployment of the tissue anchors, the first and second set of anchors may be deployed from one another at a distance sufficient to allow for the passage of elongate body  12  between the anchors without interference therefrom.  
      In another example as shown in  FIG. 26B , opening  28  may be formed directly between tissue anchors  200 ,  202 . If elongate body  12  is advanced through opening  28 , suture  204  connecting tissue anchors  200 ,  202  may simply be pushed aside towards the edge of opening  28 .  FIGS. 26C  shows yet another example where multiple pairs of tissue anchors may be utilized about the tissue opening, e.g., in addition to anchor pairs  200 ,  202  and  200 ′,  202 ′, additional anchor pairs  206 ,  208  and  206 ′,  208 ′ may be utilized in a crossing pattern.  
      In yet another example for closing opening  28  of the stomach wall,  FIGS. 27A and 27B  show another variation where elongate body  12  may have a wire, cable, or suture  210  disposed within a lumen along the length of elongate body  12  and a snare or loop  212  connected to suture  210  positioned around the lumen opening  20  of elongate body  12 . To close opening  28 , in this example, a portion of tissue  218  having opening  28  defined therein may be drawn within elongate body  12  and through snare  212  via grasper  216  disposed at a distal end of elongate member  214 . Once tissue portion  218  has been sufficiently drawn within elongate body  12 , snare  212  may be actuated via suture  210  to be drawn upon and tighten over tissue  218  to thereby close opening  28 , as shown in  FIG. 27B .  
      In yet another variation shown in  FIG. 28 , a tissue closure assembly  220  may be delivered through elongate body  12  and ejected from shapelock lumen opening  20  to close a tissue opening. Closure assembly  220  may be comprised of a distal substrate  222  having a plurality of barbs or hooks  226  disposed over its surface. A suture or wire  228  may be connected to the distal substrate  222  at a location  230 . A proximal substrate  224  may also have a plurality of barbs or hooks  226  disposed over its surface with suture or wire  228  also passing through the substrate  224  at a location  232 . Barbs or hooks  226  may be defined along the surfaces of their respective substrates  222 ,  224  which face one another when suture  228  is tightened. Moreover, substrates  222 , 224  are accordingly sized to correspond to one another and are made from a flexible material, e.g., polymeric, polyurethane, etc., such that they may be rolled or otherwise folded into elongate body  12  for endoluminal advancement through the patient body.  
      In use, when opening  28  is to be closed, distal substrate  222  may be ejected distally of opening  28  and allowed to expand. Once fully expanded, suture or wire  228  may be tightened to pull barbs or hooks  226  against the outer serosal layer of stomach tissue. Elongate body  12  may be pulled into stomach S and proximal substrate  224  may likewise be ejected and allowed to expand. With suture or wire  228  tightened, proximal substrate  224  may be urged against the inner mucosal layer of stomach tissue and into apposition against the distal substrate  222  to thereby sandwich the gastric tissue and opening  28  therebetween. Once desirably positioned, suture or wire  228  may be cut to leave the closure assembly  220  covering the opening  28  within stomach S.  
      Although various illustrative embodiments are described above, it will be evident to one skilled in the art that various changes and modifications are within the scope of the invention. Moreover, such changes, modifications, and combinations of various features from different embodiments, as practicable, are intended to be included within the scope of this disclosure. It is further intended in the appended claims to cover all such changes, modifications, and combinations that fall within the true spirit and scope of the invention.