Patent Publication Number: US-2023149188-A1

Title: Expanding devices for endoluminal interventions

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 63/279,030, filed on Nov. 12, 2021, which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     Esophageal stricture (ES) is a luminal narrowing from scar tissue, causing dysplasia. Strictures can also occur elsewhere in the gastrointestinal tract and in other organ systems, such as the urinary tract. For example, in patients with Crohn&#39;s disease, strictures are common and they may include both de novo strictures as well as strictures arising subsequent to an earlier resection. In Crohn&#39;s disease, a resection is often performed around the ileocecal valve, and a stricture can arise at the site of an anastomosis performed to rejoin the two sections of the bowel after the resection. Atresia can occur in the gastrointestinal tract. Current limitations in methods of treating atresias and strictures can negatively affect a patient health for reasons including frequent and persistent recurrence of stricture. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The teachings of the embodiments can be readily understood by considering the following detailed description in conjunction with the accompanying drawings. 
         FIGS.  1 A AND  1 B  illustrate a dual-flange stent with a first flange comprising a magnetic element and a second flange comprising a magnetic element and a balloon, where a balloon is positioned circumferentially on a magnetic element and where deflating a balloon can facilitate passing the second flange through a stricture, according to one or more embodiments. 
         FIGS.  2 A AND  2 B  illustrate the dual-flange stent of  FIGS.  1 A AND  1 B , with the balloon that comprises the second flange expanded, according to one or more embodiments. 
         FIG.  3    illustrates the dual-flange stent of  FIGS.  1 A AND  1 B , illustrating the anatomy of a stricture on which the flanges can apply longitudinal compressive force, according to one or more embodiments. 
         FIG.  4    illustrates the anatomy of the stricture of  FIG.  3   , illustrating the longitudinal compressive force, according to one or more embodiments. 
         FIG.  5    illustrates a dual-flange stent with a first flange comprising a magnetic element and a second flange comprising a magnetic element and a balloon, where the balloon is positioned on a face of a magnetic element and where deflating the balloon can facilitate passing the second flange through a stricture, according to one or more embodiments. 
         FIG.  6    illustrates the dual-flange stent of  FIG.  5    with the balloon that includes the second flange expanded, according to one or more embodiments. 
         FIG.  7    illustrates a dual-flange device where a second flange comprises a balloon, according to one or more embodiments. 
         FIG.  8    illustrates a device for anastomosis creation or stricture treatment with a first anchor including a magnetic element and a second anchor comprising a magnetic element and a balloon, according to one or more embodiments. 
         FIG.  9    illustrates a dual flange device comprising an actuator for drawing the flanges together to compress interposed tissue, according to one or more embodiments. 
         FIG.  10    illustrates a dual flange device comprising a ratcheting mechanism, according to one or more embodiments. 
         FIGS.  11 A and  11 B  illustrate a device comprising a magnetic element and a balloon, where a balloon is positioned circumferentially on an element and where deflating a balloon can facilitate passing the device through narrow or tortuous anatomy, according to one or more embodiments. 
         FIG.  12    illustrates a photograph of a device with a balloon, according to one or more embodiments. 
         FIGS.  13 A- 13 C  illustrate the response of a stricture to longitudinal compression therapy. 
         FIG.  14    illustrates a dual flange device comprising a wire mesh with an expanded configuration, according to one or more embodiments. 
         FIG.  15    illustrates a dual flange device comprising a latching mechanism, according to one or more embodiments. 
         FIG.  16    illustrates a stricture treatment device with integrated force sensors, according to an embodiment, according to one or more embodiments. 
         FIG.  17    illustrates a photo of a stricture treatment device with integrated force sensors, according to an embodiment. 
         FIG.  18    illustrates the results of treating a stricture in a porcine model using longitudinal compression. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The Figures (FIG.) and the following description relate to preferred embodiments by way of illustration only. It should be noted that from the following discussion, alternative embodiments of the structures and methods disclosed herein will be readily recognized as viable alternatives that may be employed without departing from the principles of the embodiments. 
     Reference will now be made in detail to several embodiments, examples of which are illustrated in the accompanying figures. It is noted that wherever practicable, similar or like reference numbers may be used in the figures and may indicate similar or like functionality. The figures depict embodiments for purposes of illustration only. 
     Stricture is a luminal narrowing, often associated with scar tissue. Esophageal stricture (ES) is a stricture in the esophagus. When ES persists or recurs despite multiple (&gt;5) endoscopic balloon dilations—the cornerstone of treatment for both ES and SBS—the stricture can be deemed recalcitrant. An estimated 3,000 children annually in the United States (US) have recalcitrant ES, typically secondary to surgical repair of atresia, caustic ingestion, or gastroesophageal reflux. In adults, esophageal stricture often arises after an esophageal resection in connection with esophageal cancer. An estimated 20,000 new cases of esophageal cancer are diagnosed in the US every year. 
     Stricture can occur elsewhere in the gastrointestinal tract. For example, in patients with Crohn&#39;s disease, strictures are common, and they may include both de novo strictures as well as strictures arising subsequent to an earlier resection. In Crohn&#39;s disease, stricture etiology often includes both inflammatory pathways and fibrosis. In Crohn&#39;s disease, stricture is usually characterized by significant narrowing of the lumen, usually accompanied by wall thickening. In Crohn&#39;s disease, a resection is often performed around the ileocecal valve; a stricture can arise at the site of an anastomosis performed to rejoin the two sections of the bowel after the resection. Over one million people in the U.S. have Crohn&#39;s disease or a related condition. 
     A surgeon or endoscopist can dilate a gastrointestinal tract stricture using a balloon or by another type of mechanical dilation. Dilation can provide transient relief, but can exacerbate scar tissue formation. Exacerbation of scarring can lead to recurrence of stricture. In children with esophageal stricture, serial dilations can negatively affect a child&#39;s psychosocial development. 
     Adjunct endoscopic therapies for stricture, such as injections of steroids or mitomycin C, have limited benefit and have potential undesirable complications. 
     Self-expanding stents and electrocautery incisional therapy similarly fail to achieve long-term resolution of stricture for many patients and have potential complications for many patients. Self-expanding stents can migrate from the position in which they were initially positioned, which can result in obstruction or perforation, both with potentially severe consequences for the patient. 
     Lumen-apposing stents originally designed for patients with pancreatic cysts can be used for stricture in the bowel and are less likely to migrate, but lack features and functionality to bring about resolution of the stricture. 
     Surgical options for stricture include stricturoplasty procedures, such as the Heineke-Mikulicz and the Finney technique, and procedures where a strictured segment is removed and the lumen (esophagus or bowel) sewn back together. For esophageal stricture, a segment taken from elsewhere in the gastroinstestinal tract can be used to replace a strictured segment of the esophagus. All of these are associated with tissue loss and complications such as re-stricture. Esophageal replacement surgery is usually a last resort treatment for ES and has particularly high associated morbidity and mortality. 
     If stricture interventions fail, a patient can be left with a permanent stoma. For the esophagus, this is known as a spit fistula. 
     Device systems can be designed to longitudinally compress a stricture. Springs and magnetic field effects can provide force to longitudinally compress a stricture. The term longitudinal is used to refer to compressive forces acting approximately in the direction of the stricture&#39;s length, as illustrated in  FIG.  4   . A stricture can be described by the length of the segment of lumen where there is significant narrowing of the lumen, usually accompanied by wall thickening, and by the cross-sectional area in the segment where there is significant narrowing of the lumen. 
     An anastomosis is a connection between two lumens in the body through which material can flow. For example, when a cancerous section of the colon is surgically removed, the joining together of the upstream section and the downstream section of the colon to restore continuity (i.e., to re-create a lumen through which material can flow) is referred to as surgically creating an anastomosis. Historically, GI tract anastomoses were created by hand-sewing. Later, a variety of staplers and other specialized device systems were developed to facilitate anastomosis creation. Where specialized device systems are used for anastomosis creation, the devices often comprise at least two components, where a first device component is positioned in a first lumen and a second device component is positioned in a second lumen. A surgeon brings the two device components in such a way that the two device components interact with each other and join the lumens. 
     For example, to create an anastomosis between the stomach and the small bowel for a duodenal obstruction, a surgeon may punch the anvil of a circular stapler through the stomach wall and then through a section of small bowel wall. The surgeon will then bring the anvil into the main part of the circular stapler and will then fire the staples. 
     Device systems can be designed with magnetic elements such that magnetic force can be leveraged in bringing two lumens together to create an anastomosis or to longitudinally compress a stricture. Some device systems use ring- or disk-shaped magnetic elements. 
     In practice, however, device systems with magnetic elements are not commonly used for anastomosis creation. One reason that magnetic force-based device systems have gained only limited traction for anastomosis creation is that, historically, these device systems have lacked features and functionality to accommodate challenging anatomy. For example, it can be difficult to bring magnetic device components through narrow regions of anatomy. 
     In practice, device systems for longitudinally compressing stricture tissue are not commonly used for treating stricture. One reason that longitudinal compression device systems have gained only limited traction for stricture treatment is that, historically, these device systems have lacked features and functionality to allow them to be used where the stricture can be readily accessed only from one side, for example where an esophageal stricture can be readily accessed only transorally or where a small bowel stricture can be accessed only transanally. For example, it can be difficult to pass a device component through the stricture itself in order to apply longitudinal compressive force. 
     In one embodiment, stents, including lumen apposing stents, can be used in patients with strictures in the gastrointestinal tract, with the intention of maintaining a sufficiently large opening of a stricture—that is, a segment of the gastrointestinal tract that has become narrowed—to allow for the passage of food and waste. In practice, stents that function by expanding radially outward, correspondingly forcing the mucosa radially outward, fail to bring about optimal outcomes in many patients. For example, as with balloon dilation, application of radial outward forces on a stricture by an expanding stent can exacerbate scar tissue formation. For example, self-expanding stents can migrate to another location in the gastrointestinal tract. Stents with large dual flanges, such as stents marketed as lumen-apposing stents, can have a lower likelihood of migration, but maintain the opening without having a therapeutic effect that can bring about an increase in patency greater than the dimensions of the stent&#39;s waist. 
       FIGS.  1 A AND  1 B  illustrate a dual-flange stent, according to one or more embodiments. The dual-flange stent in  FIGS.  1 A AND  1 B  can have a therapeutic effect that can bring about a marked increase in patency and durable resolution of stricture. In one embodiment,  FIG.  1 A  illustrates a cross-sectional view and  FIG.  1 B  illustrates a plan view of the stent. The stent comprises a first flange  100  that can comprise a magnetic element. The stent further comprises a shaft  130  and a second flange  102  that can comprise a magnetic element. Specifically, the second flange  102  includes a core  110  and a balloon  150  attached to the core  110 . The core  110  may include a magnetic element or may be a non-magnetic element. Attached to the core  110  is a balloon  150  that can be filled with saline or another fluid. In one instance, upon filling the balloon  150  with a fluid such as saline or another fluid, the balloon expands. The balloon  150  may expand rapidly. Thus, in one embodiment, the first flange  100  or the second flange  102  may be configured to transition between a first configuration and a second configuration, where the first configuration is compact (e.g., balloon  150  is in deflated state) and the second configuration (e.g., balloon  150  is in inflated state) provides a large tissue-compressing surface. 
     The balloon  150  can comprise materials including nylon, polyethylene terephthalate, or a low-durometer urethane. In one instance, the balloon can be blow molded. The balloon can be designed to expand radially. The balloon can be molded to have a surface that is approximately flat when, for example, the balloon  150  is an inflated state. The approximately flat surface can be oriented approximately perpendicular to the direction of expansion. The approximately flat surface can transition to a curved or beveled surface near the periphery or edge of the balloon  150 . A curved or beveled surface near the periphery can be conducive to peripheral tissue healing in stricture treatment. A curved or beveled surface near the periphery can be conducive to device detachment after an intended therapeutic effect has been achieved. The diameter of the approximately flat surface (e.g., when inflated state) can be between 8 mm and 14 mm for a device for treating esophageal stricture in pediatric patients. The diameter of the approximately flat surface can be between 14 mm and 24 mm for a device for treating esophageal stricture or small bowel stricture in adults. The balloon can have at least one structural element that confers additional stiffness in its expanded state. The structural element that confers additional stiffness can include a polymer material. In several embodiments, the polymer can be selected from the group including parylene A, parylene AM, parylene C, ammonia and/or oxygen treated parylene C, and parylene C treated with either polydopamine, vitronectin, retronectin, or matrigel. The device can include a heating element for polymerizing a structural element that confers additional stiffness to the balloon. The device can include a light source for polymerizing a structural element that confers additional stiffness to the balloon. The structural element that confers additional stiffness can be metal wire. The metal wire can be a nickel-titanium or other super-elastic or shape memory metal wire. The additional stiffness can be conferred with respect to force applied normal to portions of the face of the balloon located at or near the periphery of the balloon face In some embodiments, the stent can include more, fewer, or different components than those shown in  FIGS.  1 A and  1 B . 
     The dual-flange stent in  FIGS.  1 A AND  1 B  can comprise at least one polymer resin. The polymer resin can flow into the balloon to cause the balloon to expand radially. In one embodiment, the resin can be a combination of bisphenol A dimethacrylate,  2 -hydroxyethyl methacrylate, and urethane dimethacrylate. The polymer resin can be polymerizable through application of light, heat or directed acoustic energy. 
       FIGS.  2 A AND  2 B  illustrate the dual-flange stent of  FIGS.  1 A AND  1 B , with the balloon  150  that comprises the second flange expanded, according to one or more embodiments. In one embodiment,  FIG.  2 A  illustrates a cross-sectional view and  FIG.  2 B  illustrates a plan view of the stent with the second flange expanded. An example of the expanded balloon  150  is illustrated in  FIGS.  2 A AND  2 B . Once the balloon  150  has expanded, flanges  100  and  102  can be drawn together to compress interposed tissue. In the embodiment in which flanges  100  and  102  comprise magnetic elements, there can be an attractive force between the flanges  100  and  102  that allow the flanges  100  and  102  to be drawn together. However, it is appreciated that in other embodiments, the flanges  100  and  102  can be drawn together by any type of mechanism other than magnetic elements. For example, flanges  100  and  102  can also be drawn together by a mechanism that shortens shaft  130 , such as a telescoping structure where a smaller tube of the shaft slides within a larger tube, or a collapsing feature of the shaft. The telescoping structure can comprise a voice coil actuator or another actuator mechanism. As another example, flanges  100  and  102  can also be drawn together by a mechanism that causes the connecting shaft  130  to translate through opening  115 . As yet another example, flanges  100  and  102  can each comprise elements that generate an attractive force between the elements (other than those comprising magnets). 
       FIG.  3    illustrates the dual-flange stent of  FIGS.  1 A AND  1 B , including the anatomy of a stricture  200  on which the flanges can apply longitudinal compressive force, according to one or more embodiments. If the stent has been positioned where the first flange  100  is on one side of a stricture and the second flange  102  is on the other side of a stricture, as shown in  FIG.  3   , the tissue-contacting face  105  of the first flange  100  and the tissue-contacting face  135  of the second flange  102  can apply compressive force on tissue comprising the stricture. 
       FIG.  4    illustrates the directionality and other aspects of the application of force on the tissue comprising the stricture by the dual-flange stent of  FIGS.  1 A AND  1 B , according to one or more embodiments. Strictures can comprise fibrotic tissue. Dilating a stricture with a balloon or otherwise mechanically dilating a stricture can exacerbate the stricture by causing injury in and around fibrotic tissue comprising the stricture. 
     Compression of fibrotic tissue can cause necrosis of the fibrotic tissue. Necrosis of fibrotic tissue can lead to favorable outcomes for patients. For example, in neonates with the congenital condition esophageal atresia, fibrotic tissue can be present in and around the esophageal pouches. Compression of this fibrotic tissue between flange-like components can be conducive to the establishment of a healthy esophagus. For example, the success of magnetic anastomosis devices (such as those described in U.S. Pat. No. 8,142,454, which is incorporated by reference in its entirety) is believed to be associated with compression of fibrotic tissue. 
     It can be understood that the first flange  100  and the second flange  102  of the device illustrated in  FIG.  1 A ,  FIG.  2 A , and  FIG.  3    can longitudinally compress the stricture, including fibrotic tissue  210  comprising the stricture. 
     In some embodiments, the system can comprise a catheter  155 . In one instance, the catheter can comprise thermoplastic materials. The catheter can comprise polyether ether-ketone. The catheter can be a braided material. The catheter can reversibly attach to the first flange  100  or the second flange  102 . The shaft  130  can have an inner lumen and an outer lumen and the distal end of the catheter  155  can pass within the inner lumen of the shaft  130 . For example, the catheter can attach to a top surface of the first flange  100  or to any portion of the first flange  100 . As another example, the catheter can pass through the inner lumen of the shaft  130  and latch to an inner surface of the shaft  130 . For example, a latching mechanism can maintain the catheter within the inner lumen of the shaft or the stent. As yet another example, the catheter can pass through the inner lumen of the shaft  130  and attach to the inner surface of the second flange  102  or go through an opening of the second flange  102  and anchor to a bottom surface of the second flange  102  using, e.g., a butterfly latch mechanism. However, it is appreciated that in other embodiments, the catheter can also be attached to an outer lumen of the shaft  130 . A control mechanism at or near the proximal end of the catheter can engage or disengage the latching mechanism. In some embodiments, the system comprises an endoscope and the stent and catheter can pass through the working channel of the endoscope. The stent and catheter can be back-loaded into the working channel of the endoscope. The stent can have a flange in a first configuration (e.g. balloon  150  in a deflated state) that can pass through the stricture while the remaining flange remains on the proximal side of the stricture. 
     Referring back to  FIGS.  1 A and  1 B , with the balloon  150  in its deflated state, the outside diameter of the second flange  102  can be smaller than the outside diameter of the first flange  100 . For example, in a hypothetical esophageal stricture patient where healthy segments of the esophagus can readily pass a catheter with an outside diameter of 15 mm, while at a segment of the esophagus that has strictured, the maximum diameter of a catheter that can pass through the stricture may only be 6 mm. For example, in one embodiment, the second flange  102  may include a core  110  and a balloon  150  surrounding side surfaces  152  of the core  110 . For a magnetic element comprising the core  110  having an outside diameter of 5 mm and the added thickness of the deflated balloon 0.5 mm, the second flange  102  with deflated balloon  150  can be passed through the stricture, with the first flange  100  remaining on the proximal side of the stricture (for a stricture accessed transorally). Thus, the collapsed or deflated state of the balloon allows the second flange  102  to be sufficiently reduced in size to pass through the narrowed portion of the stricture such that the second flange can be positioned on the opposite side of the stricture relative to the first flange  100 . With inflation of the balloon  150  such that the second flange  102  reaches a diameter of 15 mm, longitudinal compression is applied on both sides of the stricture by the two flanges in a manner that can be conducive to achieving patency with an opening of approximately 15 mm, with the fibrotic tissue  210  experiencing this longitudinal compression. 
     A favorable therapeutic effect can be achieved where the tissue-contacting faces of the two flanges can draw closer together as therapy progresses. An opening  115  in the first flange  100  or second flange  102  can allow for a progressively greater length of the shaft  130  to pass through a flange, such that the tissue-contacting faces can draw closer together. 
       FIG.  5    illustrates a device for longitudinal compression of a stricture where a balloon  160  is attached on a face  137  of the core  110 , according to one or more embodiments.  FIG.  6    illustrates inflation of a balloon  160  on the face  137  of the core  110 , where the balloon  160  can apply force on a stricture, according one or more embodiments. The stent of  FIGS.  5  and  6    may be different from the stent described in conjunction with  FIGS.  1 A- 3    in that the balloon  160  is disposed on the face  137  of the core  110  rather than surrounding the side surface of the core  110 . Similar to the stent described in conjunction with  FIGS.  1 A- 3   , the stent of  FIGS.  5 - 6    can be positioned where the first flange  100  is on one side of a stricture and the second flange  102  is on the other side of a stricture. With inflation of the balloon  160  to transition the flange  102  to a second configuration that provides a large tissue-compressing surface, longitudinal compression is applied to the stricture, such that the tissue-contacting face  105  of the first flange  100  and the tissue-contacting face  135  of the second flange  102  (e.g., an inner surface of the balloon  160  in  FIG.  6   ) can apply compressive force on tissue comprising the stricture. 
       FIG.  7    illustrates a dual-flange device where a second flange comprises a balloon  150 , according to one or more embodiments. In such an embodiment, the balloon  150  itself may constitute the second flange  102 . In one embodiment, the balloon  150  can be filled with a ferrofluid. Upon filling the balloon  150  with a ferrofluid, the dual-flange can longitudinally compress a stricture due to the attraction force between a magnetic element included in the first flange  100  and the balloon  150  with the ferrofluid. The balloon  150  can be filled with a material that is polymerizable. 
     In any of the expandable devices with a balloon described herein, fluid can be introduced into a balloon by any of a variety of fittings and fluid introduction devices. A one-way valve can be incorporated into the device through which fluid can be introduced into a balloon and that can retain fluid within a balloon. A screw-on fitting can hold a fluid filling apparatus against an expandable device while fluid is introduced into a balloon. A variety of clamping fittings can hold a fluid filling apparatus against an expandable device while fluid is introduced into a balloon. 
     In any of the dual-flange devices described herein, fluid can be removed from a balloon after a period of time. Removal of fluid from a balloon after a stricture has resolved can be conducive to removal of the dual-flange device from the patient. For a balloon filled with saline, the balloon can be punctured to allow saline to be released into the gastrointestinal tract. For a balloon filled with another fluid, the fluid can be removed by a fitting. When the balloon is deflated, the second flange  102  is again reduced in size so that it can slide back through the opening and the device can be removed. 
       FIG.  8    illustrates an anastomosis device with a first anchor  200  including a magnetic element and a second anchor comprising a magnetic element  210  and a balloon  250 , according to one or more embodiments. The balloon  250  can be inflated once the second anchor is in position, for example, in the lower esophageal pouch for a patient where the anastomosis device is being used to repair esophageal atresia. With the balloon  250  in a deflated state, passage of the second anchor through narrow regions of the patient&#39;s anatomy can be easier and safer than it would be for an anchor that lacks a balloon that can be deflated. The esophageal stricture is an example of narrow anatomy where it is narrower relative to other portions of the anatomy, such as narrower than the rest of the esophagus. 
       FIG.  9    illustrates a stent incorporating an apparatus for drawing the flanges together, according to one or more embodiments. The first flange  100  may be formed with an opening  125 . The second flange  102  includes the core  110  and a balloon  150  attached to the core  110 . A linear actuator  210  in contact with the first flange  100  applies force  220  to shaft  130 , such that the shaft  130  translates upward (in the view of the drawing) through the opening  125  and the first flange  100  is pushed toward the second flange  102  to compress the interposed tissue. This in turn may cause the actuator  210  and the first flange  100  to move  225  toward the second flange  102 . While  FIG.  9    illustrates an embodiment in which the actuator  210  is attached to the first flange  100 , it is appreciated that in other embodiments, the actuator  210  may be attached to the second flange  102 , such that the shaft  130  translates downward (in the view of the drawing) through the opening  115  and the second flange  102  is pushed toward the first flange  100  to compress the interposed tissue. In some embodiments, actuators  210  may be disposed on both flanges  100  and  102  such that each flange is pushed toward the other flange simultaneously. Thus, in the embodiment of  FIG.  9   , the stent may include a linear actuator  210  for applying a force to the first flange  100  such that the first flange  100  is pushed toward the second flange  102 . In such an embodiment, the first flange  100  or the core  110  of the second flange  102  may be comprised of non-magnetic material. The linear actuator  210  can be a voice coil actuator, a piezoelectric actuator, a piezoelectric motor, a solenoid, or another kind of linear actuator. The linear actuator  210  can be located on or near a flange can be located on or near the distal end of a catheter. The linear actuator  210  may further include an integrated potentiometer for measures actuation. In another embodiment, a discrete potentiometer or other displacement or velocity or acceleration sensor measures actuation. 
       FIG.  10    illustrates a stent incorporating a ratchet mechanism  230 , according to one or more embodiments. In one embodiment, the shaft  130  is formed with one or more features  240 . In one instance, the features  240  on the shaft  130  may be one or more groove patterns formed on the surface of the shaft  130 . The first flange  100  may be formed with the ratchet mechanism  230 . The ratchet mechanism  230  may be, for example, a protrusion pattern configured to fit within a feature  240 . The ratchet mechanism  230  can engage with features  240  on the shaft  130 . In one instance, translation of the shaft  130  in the upward direction (in the view of the drawing) relative to the flange  100  can compress interposed tissue. The ratchet mechanism  230  can retain the flanges to bring about necrosis of interposed tissue. While  FIG.  10    illustrates an embodiment in which the ratchet mechanism  230  is formed on the first flange  100 , it is appreciated that in other embodiments, the ratchet mechanism  230  may be formed on the second flange  102 , or both the first flange  100  and the second flange  102 . Instead of a ratchet mechanism with groove patterns, living hinges or other elastomeric structures can apply friction that opposes translation of the shaft to have an equivalent effect of a ratcheting mechanism. 
       FIGS.  11 A and  11 B  illustrate an expanding device comprising a flange  102  that can comprise a core  110  which can be a magnetic element. The flange  102  can also comprise a balloon  150  attached to the core  110  that can be filled with saline or another fluid. In one instance, upon filling the balloon  150  with a fluid such as saline or another fluid, the balloon expands. The balloon  150  may expand rapidly. The balloon  150  can comprise materials including nylon, polyethylene terephthalate, or a low-durometer urethane. The expanding device can comprise a fitting  160  to which a filling apparatus can be attached for filling the balloon  150 . The core  110  can comprise at least one hole  165  through which fluid can flow into the balloon. The fitting  160  can comprise an elastomeric valve  170  that admits a lumen. Fluid can pass through the lumen and into the balloon  150 . Upon withdrawing the lumen, the elastomeric valve can retain the injected fluid. The valve  170  can be a septum and the lumen can be a needle that punctures the septum. The valve  170  can be a needle valve or a ball valve or another mechanical valve.  FIG.  11 A  illustrates that the at least one hole  165  is formed on a top portion of the core  110 , while  FIG.  11 B  illustrates that the at least one hole  165  is formed on a side portion of the core  110 . 
       FIG.  12    shows photographs of devices with flanges comprising balloons that can radially expand, according to one or more embodiments. These devices can compress larger areas of interposed tissue in their expanded configurations than in their unexpanded configurations. 
       FIGS.  13 A- 13 C  illustrate the therapeutic effect of longitudinal compression in an animal model of stricture. The images depict the lumen cross-sectional area at regular intervals along the length of a segment of bowel in an animal model of stricture. The measurements of lumen cross-sectional area were made using an impedance-based method (Endoflip, Medtronic).  FIG.  13 A  depicts the anatomy of a stricture prior to longitudinal compression therapy. The length of the stricture is approximately 15 mm and at its narrowest point, the lumen has a diameter of only 9.8 mm.  FIG.  13 B  depicts the anatomy of the same stricture 2 weeks after longitudinal compression therapy using devices with 21 mm diameter flange components.  FIG.  13 C  depicts the anatomy of the same stricture 9 weeks after longitudinal compression therapy. It is generally favorable for the patient where, after treatment, the lumen is enlarged, and the length of the stricture has lessened. At t=9 weeks, many strictures treated with balloon dilation will have recurred or be on a path to recurrence. In contrast, after longitudinal compression therapy, the treatment appears to be durable, with the lumen even more open than it was at t=2 weeks. 
       FIG.  14    illustrates a dual-flange stent with a second flange  102  comprising a wire mesh  138 . The wire mesh  138  has an expanded configuration as shown in  FIG.  14   . The wire mesh  138  can comprise a shape memory alloy. The wire mesh  138  can be formed in the expanded configuration and heat treated to set the expanded configuration. The wire mesh  138  can also assume a configuration where it is elongated and flattened against the shaft  130 . A latch mechanism can retain the wire mesh  138  in the elongated and flattened configuration. After passing the section of the shaft  130  with the wire mesh  138  in the elongated and flattened configuration, the latch can be released and the wire mesh  138  can assume the expanded configuration. A ratchet mechanism can draw the two flanges together to compress a stricture, similar to that described with respect to  FIG.  10   . 
       FIG.  15    illustrates a dual-flange stent with a latch mechanism. The first flange  100  comprises a first latch mechanism component  180  and the second flange  102  comprises a second latch mechanism component  185 . The description of similar components as the previous figures are omitted for the sake of brevity. As stricture treatment progresses and the distance between the tissue-contacting flange faces decreases, the latch mechanism components can engage with one another. The stricture tissue can remain compressed between the latched flanges with the ratchet mechanism detached. Other components of the dual flange stent can be removed, leaving the latched flanges in place. The latched flanges can remain in place while fibrotic tissue undergoes necrosis and while peripheral tissue heals. The timescale for peripheral tissue healing can be between 5 days and 30 days. The flanges can comprise bioabsorbable or bio-degradable material, typically a biodegradable polymer, such as poly-L-lactic acid (PLLA), polyethylene glycol modified polycaprolactone, PLGA, gelatin-modified silicone, or an anhydride polymer. For treatment of a small bowel stricture, the biodegradable polymer can pass with feces. 
       FIG.  16    illustrates an anastomosis device with a first anchor  200  comprising at least one force sensor  220 . The force sensor  220  can be a thin film force sensor. Reading the force sensor  220  can provide information about the progression of anastomosis formation or stricture treatment. 
     While embodiments herein are described primarily with respect to a dual-flange structure, it is appreciated that in other embodiments, the stent or anastomosis device may have any number of flange structures as appropriate, and one skilled in the art can devise alternative structural and functional designs through the disclosed principles, structures, and functionalities described herein. 
       FIG.  17    illustrates a photograph of a stricture treatment device, according to an embodiment, with integrated force sensors. The device also comprises a Bluetooth radio and circuitry. For example, the Bluetooth radio and circuitry may be used to transmit readings of the force sensor  220 . 
       FIG.  18    illustrates photographs of stricture treatment using longitudinal compression. The large opening  310  was a badly strictured region of the anatomy prior to treatment. The necrosed tissue  315  was fibrotic tissue constituting the stricture and was resected through the action of longitudinal compression. 
     Additional Configuration Considerations 
     Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein. 
     As used herein any reference to “one embodiment” or “an embodiment” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment. 
     Some embodiments may be described using the expression “coupled” and “connected” along with their derivatives. For example, some embodiments may be described using the term “coupled” to indicate that two or more elements are in direct physical or electrical contact. The term “coupled,” however, may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. The embodiments are not limited in this context. 
     As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). 
     In addition, use of the “a” or “an” are employed to describe elements and components of the embodiments herein. This is done merely for convenience and to give a general sense of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise. 
     Upon reading this disclosure, those of skill in the art will appreciate still additional alternative structural and functional designs through the disclosed principles herein. Thus, while particular embodiments and applications have been illustrated and described, it is to be understood that the disclosed embodiments are not limited to the precise construction and components disclosed herein. 
     Various modifications, changes and variations, which will be apparent to those skilled in the art, may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the spirit and scope defined in the appended claims.