- Email: [email protected]
EUS-Guided Anastomosis
EUS-Guided Anastomosis Takao Itoi,
MD
a,
*, Kenneth F. Binmoeller,
MD
b
KEYWORDS Endoscopic ultrasonography Pancreatic pseudocyst drainage Gallbladder drainage Entero-entero anastomosis
INTRODUCTION
Surgical anastomosis using sutures and metal titanium staples between various parts of the gastrointestinal (GI) tract and biliary tract has been the standard method to restore continuity after resection or to bypass blockage in otherwise unresectable disease. The role of flexible endoscopy has been largely limited to restoring continuity within the GI tract. Methods to create a palliative endoscopic gastroenteric or bilioenteric anastomosis have been reported in animal studies and some clinical trials. These include use of a compression button,1–3 compression coil,4 magnets,5–8 and a dedicated lumen-apposing metal stent.9,10 The role of endoscopic ultrasonography (EUS) in guiding these minimally invasive treatments has gained importance. This article focuses on a review of experimental and clinical studies of the creation of EUS-guided anastomoses. RATIONALE FOR EUS GUIDANCE
Surgical anastomosis primarily involves connecting 2 hollow organs originally not connected, such as the stomach and jejunum, stomach and bile duct, stomach and gallbladder, duodenum and bile duct, and duodenum and gallbladder. Adequate compression and closure is necessary to achieve anastomosis. Although a surgical anastomosis can be easily performed under direct visualization by a surgeon, an endoscopic anastomosis requires a series of coaxial interventions using multiple imaging modalities: endoscopy, ultrasonography, and fluoroscopy. Creation of an anastomosis under EUS guidance is attractive because it enables transenteric access to the target organ without having to cross an obstruction or surgically altered Disclosures: Drs Binmoeller and Itoi are consultants for Xlumena Inc. Dr Binmoeller serves as Xlumena’s Chief Medical Officer. Dr Itoi is a consultant and gives lectures for Olympus Medical Systems, Tokyo, Japan. a Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan; b Paul May and Frank Stein Interventional Endoscopy Services, California Pacific Medical Center, 2351 Clay Street, 6th Floor, San Francisco, CA 94115, USA * Corresponding author. E-mail address: [email protected] Gastrointest Endoscopy Clin N Am 22 (2012) 371–377 doi:10.1016/j.giec.2012.04.015 giendo.theclinics.com 1052-5157/12/$ – see front matter Ó 2012 Elsevier Inc. All rights reserved.
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anatomy. Initial access to the target organ is typically accomplished under EUS guidance with a fine-needle aspiration needle or cautery device (needle knife) followed by placement of a 0.035-in guide wire or a 0.025-in guide wire. The absence of intervening blood vessels between the 2 organs can be confirmed using Doppler imaging. The 19-gauge needle is removed and the tract dilated over the wire using a dilator catheter, balloon, and/or electrical cautery needle for bougie. Finally, stent and compression buttons are placed across the fistula. ANASTOMOSIS DEVICES Compression Buttons and Magnets
The first report on the use of a compression button by surgical insertion to create a sutureless anastomosis was described more than 100 years ago. Ischemic necrosis resulted in a leak-free anastomosis.11 Swain and Mills1 described the use of spring compression buttons and magnets to create a gastrojejunostomy in an animal study. Cope12 described creation of a successful gastroenterostomy and cholecystogastric or cholecystojejunal anastomosis13 using magnets surgically inserted in pigs.12 Cope and colleagues developed a large-bore, covered yo-yo metallic stent, which yielded long-term patency after magnetic compression anastomosis.9 Encouraged by the favorable outcomes of the experimental studies, Chopita and colleagues5 created magnetic compression gastroenteric anastomoses followed by placement of the yo-yo stent in 15 patients with malignant obstruction. The success rate was 86.6% (13 of 15 patients). One perforation occurred and was attributed to manipulation of the recently formed fistula. Three stents migrated (2 distal and 1 proximal) without further complication. In a multicenter European study, Van Hooft and colleagues14 evaluated the same technique, magnetic anastomosis device followed by the yo-yo stent. The yo-yo stent migrated in 3 of the first 7 patients (42.8%) and subsequently the investigators switched to a conventional 6-cm uncovered tubular duodenal stent design. The study was terminated after a fatal perforation in 1 patient for a total success rate of 66.7% (12 of 18 patients). Creation of magnetic biliary anastomoses has been reported by several groups. Itoi and colleagues6,7 reported creation of choledocho-choledocho anastomosis by magnetic compression using interventional radiologic and endoscopic techniques. Jamidar and colleagues15 used a novel, hinged device comprising a 7F stent with a central ferrous magnet component. The metalloplastic device was inserted into the bile duct of pigs using a standard endoscopic retrograde cholangiopancreatography (ERCP) technique over a 0.035-in guide wire. A second magnet was then endoscopically positioned in the duodenum to mate with the bile duct magnet and exert compressive ischemic force. Anastomoses ranging from 5 mm to 10 mm were successfully accomplished in all survival animals. No clinical experience using this device has been reported to date. Swain and coworkers were the first to develop and test a through-the-scope device for EUS-guided suturing and tissue approximation of the stomach with the gallbladder, and the stomach with the jejunum, in pigs.2,3 A suturing device was constructed for suturing under EUS guidance to the desired depth, and sutures were placed into both hollow and solid organs up to 5 cm from the echoendoscope tip. The device allowed multiple sutures to be placed without withdrawing the echoendoscope. Stitching, knot tying, and thread cutting were achieved through the echoendoscope’s 2.8-mm accessory channel. In that study, traction for the insertion of stents and other devices was provided through the lumens of both organs. Within 4 to 7 days, anastomoses had formed between the small intestine and the stomach and
EUS-Guided Anastomosis
between the gallbladder and the stomach. The initial diameter of the anastomoses ranged from 3 mm to 9 mm, and no adverse events were reported. Compression Coil
Chang reported the in vivo use of EUS-guided choledochoduodenostomy or cholecystoduodenostomy using a prototype compression coil in dogs.4 A prototype forward-viewing echoendoscope (Olympus Medical Systems, Tokyo, Japan) was advanced to the duodenum until the dilated common bile duct was visualized by EUS. The prototype coil delivery device (a 19-gauge needle preloaded with a stretched coil in the lumen and a screw-type stent over the needle) (Olympus) was passed through the channel of the scope. EUS-guided needle puncture into the common bile duct or gallbladder was followed by the deployment of 50% of the coil into the common bile duct or gallbladder, whereas the remaining 50% remained within the duodenal bulb to tightly secure the common bile duct or gallbladder and the duodenal walls by compressive force. Finally, a temporary stent was placed across the compression coil. As a result, in 1 of the 4 pigs in the EUS-guided choledochoduodenostomy group, successful choledochoduodenostomy resulted in device-free relief of jaundice. Histologically, there was complete adhesion between the common bile duct and the duodenum. Based on this preliminary study, he examined compression coil and twin-headed needle for EUS-guided choledochoduodenostomy in 4 dog models.16 Eventually, immediate drainage was successful in 3 of 4 dogs with overalll drainage successful in all 4 dogs. Creation of a chronic fistula between bile duct and duodenum was achieved in all 4 dogs. There was no evidence of bile leak or perforation. Lumen-Apposing Metallic Stent
EUS-guided bile duct and gallbladder drainage using a self-expandable metallic stent (SEMS) has become an alternative treatment if ERCP fails.17,18 Conventional tubular SEMSs, however, have several limitations when applied to transluminal drainage. First, they do not provide lumen-to-lumen anchorage. This may result in bile leakage and enteric contamination, because the lumens may become physically separated. Second, the stent may migrate because there is no stricture to hold it in place. Third, the exposed stent ends may cause tissue trauma, resulting in bleeding or perforation.10 In light of these limitations, a stent designed for enteric drainage of nonadherent
Fig. 1. Fully covered 10-mm 10-mm–diameter AXIOS stent with bilateral flanges.
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Fig. 2. EUS-guided cholecystoenterostomy for acute cholecystitis due to gallstones. (A) 19-gauge needle was advanced into the gallbladder under EUS imaging. (B) Cholecystography showed mutiple filling detect, suggesting gallstones. (C) Finally, the AXOS stent was placed between duodenum and gallbladder.
lumens is needed. Potential targets for anastomotic drainage include the gallbladder, bile duct, and adjacent bowel. Recently, Binmoeller and Shah10 reported on a novel removable lumen-apposing stent designed for this purpose and reported the results of benchtop tests and experimental use in pigs. The AXIOS stent (Xlumena Inc., Mountain View, CA, USA) consists of a fully covered 10-mm–diameter stent with bilateral flanges (Fig. 1). Fully expanded, the flange diameter (20 mm) is twice that of the saddle section (10 mm). The collapsible braided stent is delivered through a 10.5F catheter. The stent was successfully deployed across the stomach and gallbladder lumens in all pigs to create a robust cholecystenterostomy without complications. Direct cholecystoscopy and contrast injections were used to confirm the absence of tissue trauma or leakage. Weekly follow-up gastroscopy showed the stents to be stable and patent, without dislodgment in any animals. The covering remained intact and there was no hyperplastic tissue ingrowth, overgrowth, or tissue injury. One stent was removed at 4 weeks. On necropsy, the gallbladders showed focal adherence to the stomach at the site of cystogastrostomy and a negative leak test. The AXIOS stent is currently undergoing clinical study for internal drainage of the gallbladder (Fig. 2) and pancreatic pseudocysts (Fig. 3). The AXIOS stent may enable the creation of a bypass to the small bowel.10 A gastrojejunostomy was created under EUS guidance in 5 animals (4 survival). The stents remained fully patent in all animals throughout the implantation period (up to 4.5 weeks) and were easily removed (Fig. 4).
Fig. 3. EUS-guided cystenterostomy of the pancreatic cyst. (A) Appearance of equipment of the AXIOS. (B) A radiograph showed deployment of the dital flange of the AXIOS. (C) Deployment of the dital flange was easily detected under sonographic image. (D) Endoscopic image showed nicely deployment of the AXIOS.
EUS-Guided Anastomosis
Fig. 4. EUS-guided gastrojejunostomy in a pig model. (A) EUS view of fully deployed AXIOS stent to create gastrojejunostomy. (B) Endoscopic view of fully deployed AXIOS stent to create gastrojejunostomy.
Future developments may include a catheter-based system that delivers multiple tools in a coaxial fashion without the need for device exchange. A prototype all-inone device (AXT [Xlumena]) was evaluated in porcine survival studies with technical success in creation of a cholecystogastrostomy in 3 animals.19–22 The AXT device Luer locks to the echoendoscope and is designed for single-operator, single-hand deployment. The exchange-free system is composed of a unique anchor needle that punctures the walls of the GI tract and bile duct and maintains continuous apposition of the 2 lumens to prevent leakage of contents during instrumentation. The AXIOS stent is then delivered and deployed directly over the anchor needle. ROLE OF FORWARD-VIEWING ENDOSCOPES
The usefulness of prototype forward-viewing echoendoscopes has been described for diagnostic and therapeutic EUS.23–26 Prototype forward-viewing echoendoscopes have 2 major advantages compared with oblique-viewing echoendoscopes. First, the use of forward-viewing devices facilitates the perpendicular puncture of the GI tract wall along the same axis as the echoendoscope, which makes monitoring of the procedure easy and reliable. Second, it is possible to confirm the exchange and deployment of devices under direct endoscopic visualization. In particular, when performing 1-step stent placement for anastomosis via echoendoscopy, an obliqueviewing echoendoscope does not always provide optimal endoscopic observation. Standard and ultraslim forward-viewing upper GI endoscopes for anastomosis are also useful for diagnosis and therapy, for instance, in tissue sampling or stone removal from the gallbladder by cholecystoenteric anastomosis. LIMITATIONS OF EUS-GUIDED ANASTOMOSIS
Creation of a temporary EUS-guided anastomosis is useful, but the optimal method of maintaining permanent patency remains controversial. Large-scale prospective and randomized controlled studies of different methods and tools to create EUS-guided anastomoses are needed in the future. SUMMARY
Although some technical challenges in the development of dedicated devices need to be overcome, creation of an EUS-guided anastomosis is promising as a minimally invasive technique for pancreatobiliary diseases.
375
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ACKNOWLEDGMENTS
We are indebted to Mr Roderick J. Turner, Assistant Professor Edward F. Barroga, and Professor J. Patrick Barron, Chairman of the Department of International Medical Communications at Tokyo Medical University, for their editorial review of the English manuscript.
REFERENCES
1. Swain CP, Mills TN. Anastomosis at flexible endoscopy: an experimental study of compression button gastrojejunostomy. Gastrointest Endosc 1991;37:626–31. 2. Fritscher-Ravens A, Mosse CA, Mills TN, et al. A through-the-scope device for suturing and tissue approximation under EUS control. Gastrointest Endosc 2002;56:737–42. 3. Fritscher-Ravens A, Mosse CA, Mukherjee D. Transluminalendosurgery: single lumen access anastomotic device for flexible endoscopy. Gastrointest Endosc 2003;58:585–91. 4. Chang KJ. Endoscopic choledocho-duodenostomy (ECD) for the treatment of biliary obstruction using prototype compression coil and interventional endosonography (EUS): a “proof of principle” canine study. Gastrointest Endosc 2009; 69:S237–8. 5. Chopita N, Vaillaverde A, Cope C, et al. Endoscopic gastroenteric anastomosis using magnets. Endoscopy 2005;37:313–7. 6. Minuro A, Tsuchida A, Yamanouchi E, et al. A novel technique of magnetic compression anastomosis for severe biliary stenosis. Gastrointest Endosc 2003;58:283–7. 7. Itoi T, Yamanouchi E, Ikeda T, et al. Magnetic compression anastomosis: a novel technique for canalization of severe hilar bile duct strictures. Endoscopy 2005;37: 1248–51. 8. Jang SI, Kim JH, Won JY, et al. Magnetic compression anastomosis is useful in biliary anastomotic strictures after living donor liver transplantation. Gastrointest Endosc 2011;74:1040–8. 9. Cope C, Ginsberg GG. Long-term patency of experimental magnetic compression gastroenteric anastomoses achieved with covered stents. Gastrointest Endosc 2001;53:780–4. 10. Binmoeller KB, Shah J. A novel lumen-apposing stent for transluminal drainage of nonadherent extraintestinal fluid collections. Endoscopy 2011;43:337–42. 11. Murphy JB. Cholecysto-intestinal anastomosis, and approximation without sutures (original research). Med Rec NY 1892;42:665–76. 12. Cope C. Creation of compression gastroenterostomy by means of the oral, percutaneous, or surgical introduction of magnets: feasibility study in swine. J Vasc Interv Radiol 1995;6:539–45. 13. Cope C. Evaluation of compression cholecystogastric and cholecystojejunal anastomoses in swine after peroral and surgical introduction of magnets. J Vasc Interv Radiol 1995;6:546–52. 14. Van Hooft JE, Vleggaar FP, Le Moine O, et al. Endoscopic magnetic gastroenteric anastomosis for palliation of malignant gastric outlet obstruction: a prospective multicenter study. Gastrointest Endosc 2010;72:530–5. 15. Jamidar P, Cadeddu M, Mosse A, et al. A hinged metalloplastic anastomotic device: a novel method for choledochoduodenostomy. Gastrointest Endosc 2009;69:1333–8.
EUS-Guided Anastomosis
16. Chang KJ. EUS-guided choledocho-duodenostomy (ECD) for immediate and long-term treatment of biliary obstruction using prototype compression coil and twin-headed needle. Gastrointest Endosc 2011;73:AB326. 17. Itoi T, Coelho-Prabhu N, Baron TH. Endoscopic gallbladder drainage for management of acute cholecystitis. Gastrointest Endosc 2010;71:1038–45. 18. Itoi T, Sofuni A, Itokawa F, et al. Endoscopic ultrasonography-guided biliary drainage. J Hepatobiliary Pancreat Sci 2010;17(5):611–6. 19. Binmoeller KF, De La Mora-Levy JG. An exchange-free device for advanced translumenal therapy. Gastrointest Endosc 2010;71:AB349. 20. Binmoeller KF. A novel anchor guidewire to facilitate EUS-guided translumenal interventions. Gastrointest Endosc 2011;73:AB249. 21. Binmoeller KF, Weilert F, Marson F, et al. Self-expandable metal stent without dilatation for drainage of pancreatic fluid collection using the NAVIX access devices: initial clinical experience. Gastrointest Endosc 2011;73:AB253. 22. Binmoeller KF. EUS-guided gastrojejunostomy using novel tools designed for translumenal therapy. Gastrointest Endosc 2011;73:AB253. 23. Voermans RP, Eisendrath P, Bruno MJ, et al. Initial evaluation of a novel prototype forward-viewing US endoscope in transmural drainage of pancreatic pseudocyst drainage. Gastrointest Endosc 2007;66:1013–7. 24. De Lusong MA, Shah JN, Soetikno R, et al. Treatment of a completely obstructed colonic anastomosis stricture by using a prototype forward viewing echoendoscope and facilitated by SpyGlass. Gastrointest Endosc 2009;69:361–5. 25. Kida M, Araki M, Miyazawa S, et al. Fine needle aspiration using forward-viewing endoscopic ultrasonography. Endoscopy 2011;43:796–801. 26. Iwashita T, Nakai Y, Lee JG, et al. Newly-developed, forward-viewing echoendoscope: a comparative pilot study to the standard echoendoscope in the imaging of abdominal organs and feasibility of endoscopic ultrasound-guided interventions. J Gastroenterol Hepatol 2012;27(2):362–7.
377
MD
a,
*, Kenneth F. Binmoeller,
MD
b
KEYWORDS Endoscopic ultrasonography Pancreatic pseudocyst drainage Gallbladder drainage Entero-entero anastomosis
INTRODUCTION
Surgical anastomosis using sutures and metal titanium staples between various parts of the gastrointestinal (GI) tract and biliary tract has been the standard method to restore continuity after resection or to bypass blockage in otherwise unresectable disease. The role of flexible endoscopy has been largely limited to restoring continuity within the GI tract. Methods to create a palliative endoscopic gastroenteric or bilioenteric anastomosis have been reported in animal studies and some clinical trials. These include use of a compression button,1–3 compression coil,4 magnets,5–8 and a dedicated lumen-apposing metal stent.9,10 The role of endoscopic ultrasonography (EUS) in guiding these minimally invasive treatments has gained importance. This article focuses on a review of experimental and clinical studies of the creation of EUS-guided anastomoses. RATIONALE FOR EUS GUIDANCE
Surgical anastomosis primarily involves connecting 2 hollow organs originally not connected, such as the stomach and jejunum, stomach and bile duct, stomach and gallbladder, duodenum and bile duct, and duodenum and gallbladder. Adequate compression and closure is necessary to achieve anastomosis. Although a surgical anastomosis can be easily performed under direct visualization by a surgeon, an endoscopic anastomosis requires a series of coaxial interventions using multiple imaging modalities: endoscopy, ultrasonography, and fluoroscopy. Creation of an anastomosis under EUS guidance is attractive because it enables transenteric access to the target organ without having to cross an obstruction or surgically altered Disclosures: Drs Binmoeller and Itoi are consultants for Xlumena Inc. Dr Binmoeller serves as Xlumena’s Chief Medical Officer. Dr Itoi is a consultant and gives lectures for Olympus Medical Systems, Tokyo, Japan. a Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan; b Paul May and Frank Stein Interventional Endoscopy Services, California Pacific Medical Center, 2351 Clay Street, 6th Floor, San Francisco, CA 94115, USA * Corresponding author. E-mail address: [email protected] Gastrointest Endoscopy Clin N Am 22 (2012) 371–377 doi:10.1016/j.giec.2012.04.015 giendo.theclinics.com 1052-5157/12/$ – see front matter Ó 2012 Elsevier Inc. All rights reserved.
372
Itoi & Binmoeller
anatomy. Initial access to the target organ is typically accomplished under EUS guidance with a fine-needle aspiration needle or cautery device (needle knife) followed by placement of a 0.035-in guide wire or a 0.025-in guide wire. The absence of intervening blood vessels between the 2 organs can be confirmed using Doppler imaging. The 19-gauge needle is removed and the tract dilated over the wire using a dilator catheter, balloon, and/or electrical cautery needle for bougie. Finally, stent and compression buttons are placed across the fistula. ANASTOMOSIS DEVICES Compression Buttons and Magnets
The first report on the use of a compression button by surgical insertion to create a sutureless anastomosis was described more than 100 years ago. Ischemic necrosis resulted in a leak-free anastomosis.11 Swain and Mills1 described the use of spring compression buttons and magnets to create a gastrojejunostomy in an animal study. Cope12 described creation of a successful gastroenterostomy and cholecystogastric or cholecystojejunal anastomosis13 using magnets surgically inserted in pigs.12 Cope and colleagues developed a large-bore, covered yo-yo metallic stent, which yielded long-term patency after magnetic compression anastomosis.9 Encouraged by the favorable outcomes of the experimental studies, Chopita and colleagues5 created magnetic compression gastroenteric anastomoses followed by placement of the yo-yo stent in 15 patients with malignant obstruction. The success rate was 86.6% (13 of 15 patients). One perforation occurred and was attributed to manipulation of the recently formed fistula. Three stents migrated (2 distal and 1 proximal) without further complication. In a multicenter European study, Van Hooft and colleagues14 evaluated the same technique, magnetic anastomosis device followed by the yo-yo stent. The yo-yo stent migrated in 3 of the first 7 patients (42.8%) and subsequently the investigators switched to a conventional 6-cm uncovered tubular duodenal stent design. The study was terminated after a fatal perforation in 1 patient for a total success rate of 66.7% (12 of 18 patients). Creation of magnetic biliary anastomoses has been reported by several groups. Itoi and colleagues6,7 reported creation of choledocho-choledocho anastomosis by magnetic compression using interventional radiologic and endoscopic techniques. Jamidar and colleagues15 used a novel, hinged device comprising a 7F stent with a central ferrous magnet component. The metalloplastic device was inserted into the bile duct of pigs using a standard endoscopic retrograde cholangiopancreatography (ERCP) technique over a 0.035-in guide wire. A second magnet was then endoscopically positioned in the duodenum to mate with the bile duct magnet and exert compressive ischemic force. Anastomoses ranging from 5 mm to 10 mm were successfully accomplished in all survival animals. No clinical experience using this device has been reported to date. Swain and coworkers were the first to develop and test a through-the-scope device for EUS-guided suturing and tissue approximation of the stomach with the gallbladder, and the stomach with the jejunum, in pigs.2,3 A suturing device was constructed for suturing under EUS guidance to the desired depth, and sutures were placed into both hollow and solid organs up to 5 cm from the echoendoscope tip. The device allowed multiple sutures to be placed without withdrawing the echoendoscope. Stitching, knot tying, and thread cutting were achieved through the echoendoscope’s 2.8-mm accessory channel. In that study, traction for the insertion of stents and other devices was provided through the lumens of both organs. Within 4 to 7 days, anastomoses had formed between the small intestine and the stomach and
EUS-Guided Anastomosis
between the gallbladder and the stomach. The initial diameter of the anastomoses ranged from 3 mm to 9 mm, and no adverse events were reported. Compression Coil
Chang reported the in vivo use of EUS-guided choledochoduodenostomy or cholecystoduodenostomy using a prototype compression coil in dogs.4 A prototype forward-viewing echoendoscope (Olympus Medical Systems, Tokyo, Japan) was advanced to the duodenum until the dilated common bile duct was visualized by EUS. The prototype coil delivery device (a 19-gauge needle preloaded with a stretched coil in the lumen and a screw-type stent over the needle) (Olympus) was passed through the channel of the scope. EUS-guided needle puncture into the common bile duct or gallbladder was followed by the deployment of 50% of the coil into the common bile duct or gallbladder, whereas the remaining 50% remained within the duodenal bulb to tightly secure the common bile duct or gallbladder and the duodenal walls by compressive force. Finally, a temporary stent was placed across the compression coil. As a result, in 1 of the 4 pigs in the EUS-guided choledochoduodenostomy group, successful choledochoduodenostomy resulted in device-free relief of jaundice. Histologically, there was complete adhesion between the common bile duct and the duodenum. Based on this preliminary study, he examined compression coil and twin-headed needle for EUS-guided choledochoduodenostomy in 4 dog models.16 Eventually, immediate drainage was successful in 3 of 4 dogs with overalll drainage successful in all 4 dogs. Creation of a chronic fistula between bile duct and duodenum was achieved in all 4 dogs. There was no evidence of bile leak or perforation. Lumen-Apposing Metallic Stent
EUS-guided bile duct and gallbladder drainage using a self-expandable metallic stent (SEMS) has become an alternative treatment if ERCP fails.17,18 Conventional tubular SEMSs, however, have several limitations when applied to transluminal drainage. First, they do not provide lumen-to-lumen anchorage. This may result in bile leakage and enteric contamination, because the lumens may become physically separated. Second, the stent may migrate because there is no stricture to hold it in place. Third, the exposed stent ends may cause tissue trauma, resulting in bleeding or perforation.10 In light of these limitations, a stent designed for enteric drainage of nonadherent
Fig. 1. Fully covered 10-mm 10-mm–diameter AXIOS stent with bilateral flanges.
373
374
Itoi & Binmoeller
Fig. 2. EUS-guided cholecystoenterostomy for acute cholecystitis due to gallstones. (A) 19-gauge needle was advanced into the gallbladder under EUS imaging. (B) Cholecystography showed mutiple filling detect, suggesting gallstones. (C) Finally, the AXOS stent was placed between duodenum and gallbladder.
lumens is needed. Potential targets for anastomotic drainage include the gallbladder, bile duct, and adjacent bowel. Recently, Binmoeller and Shah10 reported on a novel removable lumen-apposing stent designed for this purpose and reported the results of benchtop tests and experimental use in pigs. The AXIOS stent (Xlumena Inc., Mountain View, CA, USA) consists of a fully covered 10-mm–diameter stent with bilateral flanges (Fig. 1). Fully expanded, the flange diameter (20 mm) is twice that of the saddle section (10 mm). The collapsible braided stent is delivered through a 10.5F catheter. The stent was successfully deployed across the stomach and gallbladder lumens in all pigs to create a robust cholecystenterostomy without complications. Direct cholecystoscopy and contrast injections were used to confirm the absence of tissue trauma or leakage. Weekly follow-up gastroscopy showed the stents to be stable and patent, without dislodgment in any animals. The covering remained intact and there was no hyperplastic tissue ingrowth, overgrowth, or tissue injury. One stent was removed at 4 weeks. On necropsy, the gallbladders showed focal adherence to the stomach at the site of cystogastrostomy and a negative leak test. The AXIOS stent is currently undergoing clinical study for internal drainage of the gallbladder (Fig. 2) and pancreatic pseudocysts (Fig. 3). The AXIOS stent may enable the creation of a bypass to the small bowel.10 A gastrojejunostomy was created under EUS guidance in 5 animals (4 survival). The stents remained fully patent in all animals throughout the implantation period (up to 4.5 weeks) and were easily removed (Fig. 4).
Fig. 3. EUS-guided cystenterostomy of the pancreatic cyst. (A) Appearance of equipment of the AXIOS. (B) A radiograph showed deployment of the dital flange of the AXIOS. (C) Deployment of the dital flange was easily detected under sonographic image. (D) Endoscopic image showed nicely deployment of the AXIOS.
EUS-Guided Anastomosis
Fig. 4. EUS-guided gastrojejunostomy in a pig model. (A) EUS view of fully deployed AXIOS stent to create gastrojejunostomy. (B) Endoscopic view of fully deployed AXIOS stent to create gastrojejunostomy.
Future developments may include a catheter-based system that delivers multiple tools in a coaxial fashion without the need for device exchange. A prototype all-inone device (AXT [Xlumena]) was evaluated in porcine survival studies with technical success in creation of a cholecystogastrostomy in 3 animals.19–22 The AXT device Luer locks to the echoendoscope and is designed for single-operator, single-hand deployment. The exchange-free system is composed of a unique anchor needle that punctures the walls of the GI tract and bile duct and maintains continuous apposition of the 2 lumens to prevent leakage of contents during instrumentation. The AXIOS stent is then delivered and deployed directly over the anchor needle. ROLE OF FORWARD-VIEWING ENDOSCOPES
The usefulness of prototype forward-viewing echoendoscopes has been described for diagnostic and therapeutic EUS.23–26 Prototype forward-viewing echoendoscopes have 2 major advantages compared with oblique-viewing echoendoscopes. First, the use of forward-viewing devices facilitates the perpendicular puncture of the GI tract wall along the same axis as the echoendoscope, which makes monitoring of the procedure easy and reliable. Second, it is possible to confirm the exchange and deployment of devices under direct endoscopic visualization. In particular, when performing 1-step stent placement for anastomosis via echoendoscopy, an obliqueviewing echoendoscope does not always provide optimal endoscopic observation. Standard and ultraslim forward-viewing upper GI endoscopes for anastomosis are also useful for diagnosis and therapy, for instance, in tissue sampling or stone removal from the gallbladder by cholecystoenteric anastomosis. LIMITATIONS OF EUS-GUIDED ANASTOMOSIS
Creation of a temporary EUS-guided anastomosis is useful, but the optimal method of maintaining permanent patency remains controversial. Large-scale prospective and randomized controlled studies of different methods and tools to create EUS-guided anastomoses are needed in the future. SUMMARY
Although some technical challenges in the development of dedicated devices need to be overcome, creation of an EUS-guided anastomosis is promising as a minimally invasive technique for pancreatobiliary diseases.
375
376
Itoi & Binmoeller
ACKNOWLEDGMENTS
We are indebted to Mr Roderick J. Turner, Assistant Professor Edward F. Barroga, and Professor J. Patrick Barron, Chairman of the Department of International Medical Communications at Tokyo Medical University, for their editorial review of the English manuscript.
REFERENCES
1. Swain CP, Mills TN. Anastomosis at flexible endoscopy: an experimental study of compression button gastrojejunostomy. Gastrointest Endosc 1991;37:626–31. 2. Fritscher-Ravens A, Mosse CA, Mills TN, et al. A through-the-scope device for suturing and tissue approximation under EUS control. Gastrointest Endosc 2002;56:737–42. 3. Fritscher-Ravens A, Mosse CA, Mukherjee D. Transluminalendosurgery: single lumen access anastomotic device for flexible endoscopy. Gastrointest Endosc 2003;58:585–91. 4. Chang KJ. Endoscopic choledocho-duodenostomy (ECD) for the treatment of biliary obstruction using prototype compression coil and interventional endosonography (EUS): a “proof of principle” canine study. Gastrointest Endosc 2009; 69:S237–8. 5. Chopita N, Vaillaverde A, Cope C, et al. Endoscopic gastroenteric anastomosis using magnets. Endoscopy 2005;37:313–7. 6. Minuro A, Tsuchida A, Yamanouchi E, et al. A novel technique of magnetic compression anastomosis for severe biliary stenosis. Gastrointest Endosc 2003;58:283–7. 7. Itoi T, Yamanouchi E, Ikeda T, et al. Magnetic compression anastomosis: a novel technique for canalization of severe hilar bile duct strictures. Endoscopy 2005;37: 1248–51. 8. Jang SI, Kim JH, Won JY, et al. Magnetic compression anastomosis is useful in biliary anastomotic strictures after living donor liver transplantation. Gastrointest Endosc 2011;74:1040–8. 9. Cope C, Ginsberg GG. Long-term patency of experimental magnetic compression gastroenteric anastomoses achieved with covered stents. Gastrointest Endosc 2001;53:780–4. 10. Binmoeller KB, Shah J. A novel lumen-apposing stent for transluminal drainage of nonadherent extraintestinal fluid collections. Endoscopy 2011;43:337–42. 11. Murphy JB. Cholecysto-intestinal anastomosis, and approximation without sutures (original research). Med Rec NY 1892;42:665–76. 12. Cope C. Creation of compression gastroenterostomy by means of the oral, percutaneous, or surgical introduction of magnets: feasibility study in swine. J Vasc Interv Radiol 1995;6:539–45. 13. Cope C. Evaluation of compression cholecystogastric and cholecystojejunal anastomoses in swine after peroral and surgical introduction of magnets. J Vasc Interv Radiol 1995;6:546–52. 14. Van Hooft JE, Vleggaar FP, Le Moine O, et al. Endoscopic magnetic gastroenteric anastomosis for palliation of malignant gastric outlet obstruction: a prospective multicenter study. Gastrointest Endosc 2010;72:530–5. 15. Jamidar P, Cadeddu M, Mosse A, et al. A hinged metalloplastic anastomotic device: a novel method for choledochoduodenostomy. Gastrointest Endosc 2009;69:1333–8.
EUS-Guided Anastomosis
16. Chang KJ. EUS-guided choledocho-duodenostomy (ECD) for immediate and long-term treatment of biliary obstruction using prototype compression coil and twin-headed needle. Gastrointest Endosc 2011;73:AB326. 17. Itoi T, Coelho-Prabhu N, Baron TH. Endoscopic gallbladder drainage for management of acute cholecystitis. Gastrointest Endosc 2010;71:1038–45. 18. Itoi T, Sofuni A, Itokawa F, et al. Endoscopic ultrasonography-guided biliary drainage. J Hepatobiliary Pancreat Sci 2010;17(5):611–6. 19. Binmoeller KF, De La Mora-Levy JG. An exchange-free device for advanced translumenal therapy. Gastrointest Endosc 2010;71:AB349. 20. Binmoeller KF. A novel anchor guidewire to facilitate EUS-guided translumenal interventions. Gastrointest Endosc 2011;73:AB249. 21. Binmoeller KF, Weilert F, Marson F, et al. Self-expandable metal stent without dilatation for drainage of pancreatic fluid collection using the NAVIX access devices: initial clinical experience. Gastrointest Endosc 2011;73:AB253. 22. Binmoeller KF. EUS-guided gastrojejunostomy using novel tools designed for translumenal therapy. Gastrointest Endosc 2011;73:AB253. 23. Voermans RP, Eisendrath P, Bruno MJ, et al. Initial evaluation of a novel prototype forward-viewing US endoscope in transmural drainage of pancreatic pseudocyst drainage. Gastrointest Endosc 2007;66:1013–7. 24. De Lusong MA, Shah JN, Soetikno R, et al. Treatment of a completely obstructed colonic anastomosis stricture by using a prototype forward viewing echoendoscope and facilitated by SpyGlass. Gastrointest Endosc 2009;69:361–5. 25. Kida M, Araki M, Miyazawa S, et al. Fine needle aspiration using forward-viewing endoscopic ultrasonography. Endoscopy 2011;43:796–801. 26. Iwashita T, Nakai Y, Lee JG, et al. Newly-developed, forward-viewing echoendoscope: a comparative pilot study to the standard echoendoscope in the imaging of abdominal organs and feasibility of endoscopic ultrasound-guided interventions. J Gastroenterol Hepatol 2012;27(2):362–7.
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