Endoscopic Closure for Full-Thickness Gastrointestinal Defects: Available Applications and Emerging Innovations

Article information

Clin Endosc. 2016;49(5):438-443
Publication date (electronic) : 2016 August 30
doi : https://doi.org/10.5946/ce.2016.104
Department of Medicine, National University of Singapore, Singapore
Correspondence: Nobuyoshi Takeshita, Department of Medicine, National University of Singapore, National University Health System (NUHS), Tower Block, Level 10, 1E Kent Ridge Road, 119228, Singapore Tel: +65-6772-4361, Fax: +65-6772-4362, E-mail: ntakeshita1225@gmail.com
Received 2016 July 18; Revised 2016 July 29; Accepted 2016 August 2.

Abstract

Full-thickness gastrointestinal defects such as perforation, anastomotic leak, and fistula are severe conditions caused by various types of pathologies. They are more likely to require intensive care and a long hospital stay and have high rates of morbidity and mortality. After intentional full-thickness opening of hollow organs for natural orifice transluminal endoscopic surgery, safe and secure closure is urgently required. The currently available advanced endoscopic closing techniques have a major role in the treatment of full-thickness gastrointestinal defects. Appropriate usage of these techniques requires taking into account their advantages and limitations during practical application. We reviewed the available endoscopic modalities, including endoscopic clips, stents, vacuum-assisted closure, gap filling, and suturing devices, discussed their advantages and limitations when treating full-thickness gastrointestinal defects, and explored emerging innovations, including a novel endoluminal surgical platform for versatile suturing and a cell-laden scaffold for effective gap filling. Although these emerging technologies still require further pre-clinical and clinical trials to assess their feasibility and efficacy, the available modalities may be replaced and refined by these new techniques in the near future.

INTRODUCTION

Full-thickness gastrointestinal defects such as perforation, leak, and fistula arise from various causes and frequently require admission to the intensive care unit and a long hospital stay [1-5]. Historically, full-thickness gastrointestinal defects have been treated with a combination of reoperation, drainage, antibiotic therapy, and total parenteral nutrition [6-8]. However, despite the availability of these options, these defects are still strongly associated with a high rate of morbidity and mortality. For example, mortality rates for anastomotic leak after esophagectomy have been reported to range from 30% to 60% [9-11].

In the field of minimally invasive surgery, natural orifice transluminal endoscopic surgery (NOTES) is an emerging endoscopic procedure performed in the abdominal cavity through full-thickness openings of hollow organs. Planned perforations for NOTES access require a safe and secure full-thickness closure to reduce the risk of dehiscence and intra-abdominal abscess. Therefore, management of full-thickness defects is necessary for NOTES procedures as well.

With the currently available applications, it is possible to manage gastrointestinal defects without surgery. However, there are some limitations and disadvantages associated with each of the procedures. Here, we review the available endoscopic modalities for the management of gastrointestinal defects, including endoscopic clips, stents, vacuum-assisted closure (VAC), gap filling, and suturing devices, and explore the emerging innovations.

ENDOSCOPIC CLIPS

Through-the-scope clips (TTSCs) are introduced through the biopsy channel. They were first designed for the management of gastrointestinal bleeding. Recently, TTSCs have been used for the closure of gastrointestinal perforations [12,13]. These clips are preferred because of their ease of use and rotatable, re-openable, and off-the-shelf features. TTSCs have been reported to be successful for iatrogenic perforations and fistulas in the gastrointestinal tract, with success rates ranging from 59% to 83% [14,15]. The limitations of TTSCs are their smaller size and smaller closing force.

Over-the-scope clips (OTSCs; Ovesco Endoscopy, Tübingen, Germany) enable closure of full-thickness defects measuring 2 cm or smaller in diameter [16]. A twin grasper and a tissue anchor are quite useful for pulling the tissues into the cap and reducing the size of the gap before deployment. Due to their larger size and larger closing force, OTSCs can close large defects and achieve full-thickness bites of the surrounding tissues. OTSCs have been reported to be successful for closing gastrointestinal defects, with long-term success rates ranging from 71% to 100% [17-21]. One retrospective study of patients with acute perforations, leaks, and fistulas treated with OTSCs reported long-term success rates of 90%, 73%, and 43%, respectively [22]. Chronic leak and fistula with inflammation are believed to be the main reasons for closure failures with OTSCs [23]. Care must be taken when introducing OTSCs because their bigger size can sometimes cause iatrogenic perforations [24].

The combination of TTSCs and a detachable snare (MAJ-340; Olympus Optical Co., Miami, FL, USA) has recently been proven as a promising option for closing larger gastrointestinal defects. This combination was first developed with a two-channel endoscope for larger mucosal defects after endoscopic resection [25]. A detachable snare is initially placed around the defect. Then, TTSCs are applied to the snare with the surrounding tissues to fix them around the defect. Subsequently, the detachable snare is tightened to close the gap [26]. However, this method is not always useful in some situations, and the success rate was only 61% in this study [25].

STENTS

It is common to use stents to cover full-thickness defects in the stomach after bariatric surgery and in the esophagus and colon. Stent placement is effective due to the diversion of enteric contents away from the defect. Various types of stents have been used, such as metallic (partially or fully covered), plastic, and biodegradable. Stent deployment often enables continuation of oral intake and can be useful for larger defects [ 7,27,28]. However, stents tend to migrate in 20% to 30% of cases lacking stenosis and thus require frequent radiographic observation [28,29]. Another concern regarding this procedure is the necessity of removal; appropriately timing endoscopic removal can sometimes be difficult. In a study of patients with esophageal leaks, the success rate was 85% and there were no significant differences between plastic stents and fully or partially covered metal stents [30]. The migration rates were higher for plastic stents and fully covered metal stents compared to partially covered metal stents (31%, 26%, and 12%, respectively). Partially covered stents allow tissue in-growth, and this phenomenon can prevent stent migration; however, it also can interfere with safe endoscopic removal. A meta-analysis of seven studies regarding leaks after bariatric surgery reported a success rate of 88% and a migration rate of 17% [31]. The use of biodegradable stents for patients with esophageal leaks was reported in another study [32]. The success rate was 80%, but the migration rate was 60% during follow-up. Additional clip placement or suturing to prevent migration may be useful. One study reported that additional clips to anchor the stents were useful; migration rates were 13% for patients with additional clips and 34% for patients without them [33]. Another study regarding esophageal leaks mentioned the possibility of extension of the anastomotic dehiscence or the erosion of the stent into the trachea and large vessels [34].

VACUUM-ASSISTED CLOSURE

VAC has been used for esophageal and colorectal leaks. VAC therapy is performed with a porous polyurethane sponge mounted at the tip of a gastric tube. This device is introduced using endoscopic forceps and is placed into the defect. Then, controlled, continuous, negative pressure is applied. The sponge needs to be changed every 2 to 5 days; it continuously removes wound secretions and interstitial edema. To achieve improved micro-circulation and granulation of the wound, the healing process is promoted [35]. One study regarding VAC therapy reported that the success rate was 93% for patients with esophageal leaks [36]. In another study of five patients with esophageal leaks, the success rate of VAC therapy was 100% and the median length of the treatments was 28 days with nine sponge changes [37]. Two of these five patients presented with stenosis and one experienced severe bleeding after endoscopic dilation due to an aorto-anastomotic fistula.

GAP FILLING

Fibrin glue and cyanoacrylate are sealants that have been used to fill gastrointestinal defects [38,39]. Fibrin glue, a biologic sealant, is composed of fibrinogen and thrombin. It is applied with a double lumen catheter and then combined to form an acellular clot in the defects. Fibrin glue injected submucosally has been reported to have caused a wheal and subsequent occlusion of a tracheoesophageal fistula [40]. Another study of 15 patients with a gastrointestinal fistula reported that fibrin glue was used to fill the fistula; on average, the success rate was 87% after 2.5 sessions [38]. Another report mentioned a success rate of only 50% for cases of severe inflammation [41]. Cyanoacrylate, a synthetic sealant, has the advantage of strong adhesive and antibacterial characteristics. Therefore, it is considered suitable for application in infectious or wet environments and has been reported to be successful for closing an esophagojejunal anastomotic leak [39].

Surgisis (Cook Surgical, Bloomington, IN, USA) is an acellular bioactive prosthetic biomatrix derived from small intestinal submucosa of sheep [42]. This device was developed for the treatment of anal fistulas and has been used to successfully treat gastrocutaneous fistulas after bariatric surgery [43]. In one study, Surgisis was used endoscopically to occlude gastrointestinal fistulas; it had an 80% long-term success rate [44]. Vicryl plug in combination with fibrin glue has been successful in 87% of patients with gastrointestinal defects after surgery for esophageal cancer [45]. The number of sessions required for Vicryl plug and fibrin glue applications ranges from one to four. However, the author mentioned that it is best to apply this method when the size of the defect has decreased to 1.5 cm and when the site appears clean on lavage.

SUTURING DEVICES

The Overstitch Endoscopic Suturing System (Apollo Endosurgery, Austin, TX, USA) is a suturing device mounted at the tip of a double-channel endoscope. This device enables placement of full-thickness sutures and multiple uses without endoscopic removal. It has been used to close acute perforations as well as ulcerations after endoscopic resection [46,47]. In one study using a treat-and-resect model, the Overstitch system was able to place sutures consistently at a subserosal depth in the colon without injury to the surrounding organs [48]. It has also been successfully used for the closure of leaks after bariatric surgery and esophagopleural and gastrocutaneous fistulas [49-52]. However, in another study of patients with gastrogastric fistulas that were closed using another suturing device (EndoCinch; CR BARD, Billerica, MA, USA), the long-term success rate was 35%, despite a 95% initial closure rate [53]. Furthermore, another animal study reported that the procedure time for endoluminal closure was 1 hour, on average, even though the team had experience using this technique [54]. These findings suggest lingering issues regarding technical difficulty.

EMERGING INNOVATIONS

Although a number of options are available for repairing gastrointestinal defects, each still has several limitations and disadvantages (Table 1). A method for substantial and durable full-thickness closing of large defects is still required. We believe that the key items needed for successful closure are a versatile suturing device and effective gap-filling material.

Advantages and Disadvantages of Different Endoscopic Modalities

Our group developed the master and slave transluminal endoscopic robot (MASTER) as a novel endoluminal surgical platform. It has two operating arms equipped with multiple degrees of freedom; thus, enabling dexterity with surgical maneuvers such as triangulation, retraction, grasping, and cutting [55]. Using this platform, we will be developing an intuitive suturing method characterized by adjustability and versatility (Fig. 1). This platform can also be combined with existing methods such as endoscopic clips. By means of grasping and traction, the MASTER system can provide a suitable situation for clip application (Fig. 2). With regard to gap-filling materials, cell-laden scaffolds that have been accepted in the skin or orthopedic area are promising for treating gastrointestinal defects [56,57]. We believe that gastrointestinal fibroblasts cultured on biodegradable and biocompatible materials (e.g., polycaprolactone) fabricated using three-dimensional printing techniques will prove suitable for implants to fill the defects in terms of growth efficacy and secretion of growth factors (Fig. 3).

Fig. 1.

Master and slave transluminal endoscopic robot suturing with adjustability and versatility in a dry setting.

Fig. 2.

Collaboration between master and slave transluminal endoscopic robot and endoscopic clips in an animal experiment. The grasper holds the defect and provides a suitable situation for clip application.

Fig. 3.

Esophageal fibroblasts cultured on a polycaprolactone scaffold fabricated using a three-dimensional printing technique. (A) Polycaprolactone scaffold (B) before fibroblast seeding and (C, D) after fibroblast culture (day 14).

CONCLUSIONS

Gastrointestinal defects can be managed without surgery, but we still need further innovations and new technologies to achieve ideal clinical outcomes. Although the emerging technologies demand further pre-clinical or clinical trials to assess their feasibility and efficacy, the presently available applications may eventually be replaced and refined by these new techniques in the near future.

Notes

Conflicts of Interest: K.Y.H. is a co-founder of EndoMaster Pte Ltd.

Acknowledgements

The authors thank Wu Bin and Professor Jerry Fuh, Department of Mechanical Engineering, National University of Singapore, for providing the polycaprolactone scaffolds.

References

1. Goenka MK, Goenka U. Endotherapy of leaks and fistula. World J Gastrointest Endosc 2015;7:702–713.
2. Hulscher JB, van Sandick JW, de Boer AG, et al. Extended transthoracic resection compared with limited transhiatal resection for adenocarcinoma of the esophagus. N Engl J Med 2002;347:1662–1669.
3. Orringer MB, Marshall B, Chang AC, Lee J, Pickens A, Lau CL. Two thousand transhiatal esophagectomies: changing trends, lessons learned. Ann Surg 2007;246:363–372.
4. Biere SS, van Berge Henegouwen MI, Maas KW, et al. Minimally invasive versus open oesophagectomy for patients with oesophageal cancer: a multicentre, open-label, randomised controlled trial. Lancet 2012;379:1887–1892.
5. Luketich JD, Pennathur A, Awais O, et al. Outcomes after minimally invasive esophagectomy: review of over 1000 patients. Ann Surg 2012;256:95–103.
6. Michel L, Grillo HC, Malt RA. Operative and nonoperative management of esophageal perforations. Ann Surg 1981;194:57–63.
7. Eroglu A, Turkyilmaz A, Aydin Y, Yekeler E, Karaoglanoglu N. Current management of esophageal perforation: 20 years experience. Dis Esophagus 2009;22:374–380.
8. Maroney TP, Ring EJ, Gordon RL, Pellegrini CA. Role of interventional radiology in the management of major esophageal leaks. Radiology 1989;170(3 Pt 2):1055–1057.
9. Patil PK, Patel SG, Mistry RC, Deshpande RK, Desai PB. Cancer of the esophagus: esophagogastric anastomotic leak: a retrospective study of predisposing factors. J Surg Oncol 1992;49:163–167.
10. Alanezi K, Urschel JD. Mortality secondary to esophageal anastomotic leak. Ann Thorac Cardiovasc Surg 2004;10:71–75.
11. Junemann-Ramirez M, Awan MY, Khan ZM, Rahamim JS. Anastomotic leakage post-esophagogastrectomy for esophageal carcinoma: retrospective analysis of predictive factors, management and influence on longterm survival in a high volume centre. Eur J Cardiothorac Surg 2005;27:3–7.
12. Binmoeller KF, Grimm H, Soehendra N. Endoscopic closure of a perforation using metallic clips after snare excision of a gastric leiomyoma. Gastrointest Endosc 1993;39:172–174.
13. Yoshikane H, Hidano H, Sakakibara A, et al. Endoscopic repair by clipping of iatrogenic colonic perforation. Gastrointest Endosc 1997;46:464–466.
14. Magdeburg R, Collet P, Post S, Kaehler G. Endoclipping of iatrogenic colonic perforation to avoid surgery. Surg Endosc 2008;22:1500–1504.
15. Cho SB, Lee WS, Joo YE, et al. Therapeutic options for iatrogenic colon perforation: feasibility of endoscopic clip closure and predictors of the need for early surgery. Surg Endosc 2012;26:473–479.
16. Al Ghossaini N, Lucidarme D, Bulois P. Endoscopic treatment of iatrogenic gastrointestinal perforations: an overview. Dig Liver Dis 2014;46:195–203.
17. Lee WC, Ko WJ, Cho JH, et al. Endoscopic treatment of various gastrointestinal tract defects with an over-the-scope clip: case series from a tertiary referral hospital. Clin Endosc 2014;47:178–182.
18. Mercky P, Gonzalez JM, Aimore Bonin E, et al. Usefulness of over-the-scope clipping system for closing digestive fistulas. Dig Endosc 2015;27:18–24.
19. Kouklakis G, Zezos P, Liratzopoulos N, et al. Endoscopic treatment of a gastrocutaneous fistula using the over-the-scope-clip system: a case report. Diagn Ther Endosc 2011;2011:384143.
20. Manta R, Manno M, Bertani H, et al. Endoscopic treatment of gastrointestinal fistulas using an over-the-scope clip (OTSC) device: case series from a tertiary referral center. Endoscopy 2011;43:545–548.
21. Mennigen R, Colombo-Benkmann M, Senninger N, Laukoetter M. Endoscopic closure of postoperative gastrointestinal leakages and fistulas with the over-the-scope clip (OTSC). J Gastrointest Surg 2013;17:1058–1065.
22. Haito-Chavez Y, Law JK, Kratt T, et al. International multicenter experience with an over-the-scope clipping device for endoscopic management of GI defects (with video). Gastrointest Endosc 2014;80:610–622.
23. Mennigen R, Senninger N, Laukoetter MG. Novel treatment options for perforations of the upper gastrointestinal tract: endoscopic vacuum therapy and over-the-scope clips. World J Gastroenterol 2014;20:7767–7776.
24. Voermans RP, Le Moine O, von Renteln D, et al. Efficacy of endoscopic closure of acute perforations of the gastrointestinal tract. Clin Gastroenterol Hepatol 2012;10:603–608.
25. Lee BI, Kim BW, Kim HK, et al. Routine mucosal closure with a detachable snare and clips after endoscopic submucosal dissection for gastric epithelial neoplasms: a randomized controlled trial. Gut Liver 2011;5:454–459.
26. Kim YJ, Shin SK, Lee HJ, et al. Endoscopic management of anastomotic leakage after gastrectomy for gastric cancer: how efficacious is it? Scand J Gastroenterol 2013;48:111–118.
27. D’Cunha J, Rueth NM, Groth SS, Maddaus MA, Andrade RS, et al. Esophageal stents for anastomotic leaks and perforations. J Thorac Cardiovasc Surg 2011;142:39–46. e1.
28. Gelbmann CM, Ratiu NL, Rath HC, et al. Use of self-expandable plastic stents for the treatment of esophageal perforations and symptomatic anastomotic leaks. Endoscopy 2004;36:695–699.
29. Dai Y, Chopra SS, Steinbach M, Kneif S, Hunerbein M. Esophageal stents for leaks and perforations. Semin Thorac Cardiovasc Surg 2011;23:159–162.
30. van Boeckel PG, Sijbring A, Vleggaar FP, Siersema PD. Systematic review: temporary stent placement for benign rupture or anastomotic leak of the oesophagus. Aliment Pharmacol Ther 2011;33:1292–1301.
31. Puli SR, Spofford IS, Thompson CC. Use of self-expandable stents in the treatment of bariatric surgery leaks: a systematic review and meta-analysis. Gastrointest Endosc 2012;75:287–293.
32. Černá M, Köcher M, Válek V, et al. Covered biodegradable stent: new therapeutic option for the management of esophageal perforation or anastomotic leak. Cardiovasc Intervent Radiol 2011;34:1267–1271.
33. Vanbiervliet G, Filippi J, Karimdjee BS, et al. The role of clips in preventing migration of fully covered metallic esophageal stents: a pilot comparative study. Surg Endosc 2012;26:53–59.
34. Schaheen L, Blackmon SH, Nason KS. Optimal approach to the management of intrathoracic esophageal leak following esophagectomy: a systematic review. Am J Surg 2014;208:536–543.
35. Venturi ML, Attinger CE, Mesbahi AN, Hess CL, Graw KS. Mechanisms and clinical applications of the vacuum-assisted closure (VAC) Device: a review. Am J Clin Dermatol 2005;6:185–194.
36. Loske G, Schorsch T, Müller C. Intraluminal and intracavitary vacuum therapy for esophageal leakage: a new endoscopic minimally invasive approach. Endoscopy 2011;43:540–544.
37. Ahrens M, Schulte T, Egberts J, et al. Drainage of esophageal leakage using endoscopic vacuum therapy: a prospective pilot study. Endoscopy 2010;42:693–698.
38. Rábago LR, Ventosa N, Castro JL, Marco J, Herrera N, Gea F. Endoscopic treatment of postoperative fistulas resistant to conservative management using biological fibrin glue. Endoscopy 2002;34:632–638.
39. Pramateftakis MG, Vrakas G, Kanellos I, et al. Endoscopic application of n-butyl-2-cyanoacrylate on esophagojejunal anastomotic leak: a case report. J Med Case Rep 2011;5:96.
40. Farra J, Zhuge Y, Neville HL, Thompson WR, Sola JE. Submucosal fibrin glue injection for closure of recurrent tracheoesophageal fistula. Pediatr Surg Int 2010;26:237–240.
41. Lippert E, Klebl FH, Schweller F, et al. Fibrin glue in the endoscopic treatment of fistulae and anastomotic leakages of the gastrointestinal tract. Int J Colorectal Dis 2011;26:303–311.
42. Tringali A, Daniel FB, Familiari P, et al. Endoscopic treatment of a recalcitrant esophageal fistula with new tools: stents, surgisis, and nitinol staples (with video). Gastrointest Endosc 2010;72:647–650.
43. Toussaint E, Eisendrath P, Kwan V, Dugardeyn S, Devière J, Le Moine O. Endoscopic treatment of postoperative enterocutaneous fistulas after bariatric surgery with the use of a fistula plug: report of five cases. Endoscopy 2009;41:560–563.
44. Maluf-Filho F, Hondo F, Halwan B, de Lima MS, Giordano-Nappi JH, Sakai P. Endoscopic treatment of Roux-en-Y gastric bypass-related gastrocutaneous fistulas using a novel biomaterial. Surg Endosc 2009;23:1541–1545.
45. Bohm G, Mossdorf A, Klink C, et al. Treatment algorithm for postoperative upper gastrointestinal fistulas and leaks using combined vicryl plug and fibrin glue. Endoscopy 2010;42:599–602.
46. Henderson JB, Sorser SA, Atia AN, Catalano MF. Repair of esophageal perforations using a novel endoscopic suturing system. Gastrointest Endosc 2014;80:535–537.
47. Juza RM, Pauli EM, Mathew A. Endoscopic resection of a gastric gastrointestinal stromal cell tumor with full thickness defect closure using endoscopic suturing device. In : 2014 American College of Surgeons (ACS) Clinical Congress; 2014 Oct 27; San Fransisco, CA.
48. Pauli EM, Delaney CP, Champagne B, Stein S, Marks JM. Safety and effectiveness of an endoscopic suturing device in a human colonic treat-and-resect model. Surg Innov 2013;20:594–599.
49. Pauli EM, Beshir H, Mathew A. Gastrogastric fistulae following gastric bypass surgery-clinical recognition and treatment. Curr Gastroenterol Rep 2014;16:405.
50. Cai JX, Khashab MA, Okolo PI 3rd, Kalloo AN, Kumbhari V. Full-thickness endoscopic suturing of staple-line leaks following laparoscopic sleeve gastrectomy. Endoscopy 2014;46 Suppl 1 UCTN:E623–E624.
51. Bonin EA, Wong Kee Song LM, Gostout ZS, Bingener J, Gostout CJ. Closure of a persistent esophagopleural fistula assisted by a novel endoscopic suturing system. Endoscopy 2012;44 Suppl 2 UCTN:E8–E9.
52. Kantsevoy SV, Thuluvath PJ. Successful closure of a chronic refractory gastrocutaneous fistula with a new endoscopic suturing device (with video). Gastrointest Endosc 2012;75:688–690.
53. Fernandez-Esparrach G, Lautz DB, Thompson CC. Endoscopic repair of gastrogastric fistula after Roux-en-Y gastric bypass: a less-invasive approach. Surg Obes Relat Dis 2010;6:282–288.
54. Halvax P, Diana M, Lègner A, et al. Endoluminal full-thickness suture repair of gastrotomy: a survival study. Surg Endosc 2015;29:3404–3408.
55. Phee SJ, Low SC, Huynh VA, Kencana AP, Sun ZL, Yang K. Master and slave transluminal endoscopic robot (MASTER) for natural orifice transluminal endoscopic surgery (NOTES). Conf Proc IEEE Eng Med Biol Soc 2009;2009:1192–1195.
56. Bonvallet PP, Schultz MJ, Mitchell EH, et al. Microporous dermal-mimetic electrospun scaffolds pre-seeded with fibroblasts promote tissue regeneration in full-thickness skin wounds. PLoS One 2015;10e0122359.
57. Li JL, Cai YL, Guo YL, et al. Fabrication of three-dimensional porous scaffolds with controlled filament orientation and large pore size via an improved E-jetting technique. J Biomed Mater Res B Appl Biomater 2014;102:651–658.

Article information Continued

Fig. 1.

Master and slave transluminal endoscopic robot suturing with adjustability and versatility in a dry setting.

Fig. 2.

Collaboration between master and slave transluminal endoscopic robot and endoscopic clips in an animal experiment. The grasper holds the defect and provides a suitable situation for clip application.

Fig. 3.

Esophageal fibroblasts cultured on a polycaprolactone scaffold fabricated using a three-dimensional printing technique. (A) Polycaprolactone scaffold (B) before fibroblast seeding and (C, D) after fibroblast culture (day 14).

Table 1.

Advantages and Disadvantages of Different Endoscopic Modalities

Advantages Disadvantages
TTSC Cheap cost, easy handling Small size, small closing force
OTSC Large closing force Low success rate for chronic leak and fistulae with inflammation
Stent Permitting enteral nutrition, usefulness for larger defect Migration, requiring removal
VAC High success rate Discomfort, requiring frequent procedures
Gap filling Availability of various kinds of biomaterials Small size
Suturing device Permitting placement of full-thickness suture Low long-term success rate, technical difficulty

TTSC, through-the-scope clip; OTSC, over-the-scope clip; VAC, vacuum-assisted closure.