Magnetic compression anastomosis in gastrointestinal and biliary disease: Techniques and clinical applications

Abstract

Magnetic compression anastomosis (MCA) is an emerging minimally invasive technique that enables the creation of gastrointestinal anastomoses without surgical suturing or stapling. This technique involves the placement of paired magnets across an obstructed or discontinuous lumen, generating localized compression that induces ischemic necrosis of the intervening tissue, and subsequent formation of a neo-anastomotic tract. Over the past decade, MCA has gained increasing attention in the management of complex gastrointestinal and biliary conditions, particularly in patients with refractory benign biliary strictures, esophageal atresia, postoperative anastomotic obstruction, and challenging surgical anatomies. Published studies have reported high technical and clinical success rates in carefully selected patients; however, complications such as restenosis, delayed anastomotic maturation, and magnet-related adverse events remain crucial concerns. Additional prospective studies and standardized procedural protocols are required to better define the optimal indications, safety profiles, and long-term efficacy of MCA for gastrointestinal and biliary interventions. This mini-review summarizes the current available evidence on MCA, including experimental models, technical considerations, magnet design, delivery approaches, and alignment strategies.

Key Words: Magnetic compression anastomosis; Biliary stricture; Esophageal stricture; Benign strictures; Neo-fistula; Endoscopic-percutaneous rendezvous; Gastroenteric bypass; Refractory strictures

Core Tip: Magnetic compression anastomosis is a minimally invasive technique that creates a new lumen by compressing tissue between paired magnets until a tract forms and matures. The strongest clinical evidence exists for completely obstructed benign biliary strictures in which guidewire passage is not possible. Key determinants of successful outcomes include short stricture length, stable magnet alignment, appropriate compression force, and structured postprocedural calibration with dilation or temporary stenting. Although magnetic compression anastomosis is promising, it currently relies mainly on observational studies, and further prospective research is needed to establish standardized indications and long-term outcomes.

INTRODUCTION

Magnetic compression anastomosis (MCA) is a sutureless technique that creates a luminal anastomosis by placing two magnets on either side of an obstructed or transected segment[1,2]. This technique has been used in various gastrointestinal and biliary settings. Unlike conventional endoscopic dilation or stenting, which requires at least a traversable lumen, MCA is a recanalization and reconstruction technique designed for “no-wire” situations[3]. Benign strictures of the biliary and gastrointestinal tract, such as postsurgical anastomotic strictures or inflammatory strictures, can be difficult to treat and may be refractory to standard techniques. Conventional management involves endoscopic or percutaneous approaches, including balloon dilation or placement of plastic or metal stents, which are usually successful only when a guidewire can traverse the stricture. Similarly, congenital atresia [e.g., long-gap esophageal atresia (EA)] or severe postoperative strictures in the esophagus or colon may result in complete luminal obstruction. In these situations, MCA has emerged as a technique to restore luminal continuity and has progressed from early proof-of-concept reports to structured clinical series with long-term follow-up, supporting its role as salvage therapy in selected patients[2,4,5].

The concept of MCA originates from the Murphy button, which enables circular intestinal anastomosis through ischemic compression[6,7]. The modern experimental form of MCA was first introduced in 1970, and the first human application was reported by Yamanouchi in 1998 who successfully created a bile duct-small intestinal fistula[8]. Since 2000, MCA has gained increasing clinical use in various gastrointestinal anastomoses, supported by extensive animal and clinical studies. However, the current evidence is mainly derived from small case series and noncomparative observational studies, and large multicenter studies with long-term follow-up are still required to establish its long-term effectiveness. Additional challenges include the lack of standardized preprocedural assessment tools, technical variability between procedures, and limited availability of magnetic devices and related equipment required for the procedure. This review summarizes the current evidence on MCA, including key technical considerations, clinical success, adverse events, and outcomes in the management of complex biliary and gastrointestinal strictures.

SEARCH STRATEGY

A PubMed search was conducted to identify studies reporting the clinical use of MCA for gastrointestinal and biliary diseases. The search included articles published from database inception to March 2026 and used combinations of the following keywords: “magnetic compression anastomosis”, “magnamosis”, “magnetic anastomosis”, “biliary stricture”, “esophageal atresia”, “gastrointestinal anastomosis”, and “intestinal anastomosis”. Studies published in English that reported clinical outcomes of MCA in humans were included. Case reports and case series involving fewer than three patients were excluded; however, selected case reports were included in the descriptive discussion when they were considered innovative or historically significant. The reference lists of the included studies were also manually screened to identify additional relevant articles. A total of 155 studies were screened, of which 32 met the inclusion criteria, and selected case reports were incorporated into this narrative review (Figure 1). Data extracted from each study included the study design, number of patients, indication and anatomical site of MCA, clinical endpoints, technical success, clinical success, and reported adverse events.

Figure 1 Flow diagram of study selection. The diagram summarises the identification, screening, exclusion, and inclusion of studies used in the narrative review and evidence tables. ¹Selected case reports were included in the descriptive discussion when they were innovative or of historical significance. PICO: Patient population, intervention, comparison, and outcome.

Technical considerations

MCA depends on a predictable biological sequence initiated by sustained localized compression between two magnets positioned across a stricture or occlusion. When the magnets couple across the target segment, the compressed tissue undergoes progressive hypoperfusion and necrosis. Over the following days, the necrotic tissue sloughs, resulting in lumen formation; granulation tissue bridges the defect; and the tract subsequently remodels through epithelialization and fibrosis to form a mature anastomosis. Clinically, MCA is best understood as a two-stage therapy consisting of magnet deployment and coupling to create the tract, followed by Postcreation calibration by using balloon dilation and/or temporary internal stenting to optimize the final luminal diameter and reduce restenosis. Successful magnet deployment requires maintenance of access routes to both the proximal and distal ends of the stricture as well as the accurate alignment and approximation of the magnets through their mutual attraction (Figures 2 and 3). Once approximated, the magnets create a neo-fistula and subsequently either migrate into the lumen spontaneously or are removed endoscopically. Multiple studies have indicated that structured calibration and temporary stenting are essential for achieving durable long-term patency[3,9-12]. Unlike biliary or esophageal MCA, routine dilation is generally unnecessary in colorectal or enteroenteric applications because the larger intestinal lumen usually maintains adequate anastomotic patency[13]. A major limitation of MCA is that anastomosis formation occurs gradually over time rather than immediately. However, optimization of magnetic device design may shorten the time required for anastomosis formation[14].

Figure 2 Magnetic compression anastomosis for biliary stricture. A: Post-operative or post-transplant biliary stricture; B: Delivery of Proximal and distal magnet via percutaneous transhepatic catheter and endoscopy; C: Magnet approximated and stricture being negotiated by wire; D: Once neo-fistula formed and wire negotiated, stent is placed to maintain the patency of the fistula.

Figure 3 Representative access routes for magnetic compression anastomosis in gastrointestinal and biliary disease. A: Bilioenteric anastomotic stricture approached through transhepatic and enteroscopic routes; B: Esophageal anastomotic stricture approached through oral endoscopy and gastrostomy access; C: Colorectal stricture approached through colonoscopic and distal luminal access. PEG: Percutaneous endoscopic gastrostomy.

Magnet design

Most MCA systems use rare-earth magnets, typically neodymium-iron-boron or samarium-cobalt magnets, because they provide high magnetic field strength in a compact form[3]. The use of strong rare-earth magnets to create compression anastomosis was investigated as early as 1990 when animal studies demonstrated the feasibility and safety of this technique for creating bilioenteric and enteroenteric anastomoses in pigs[15,16]. Among these materials, neodymium-iron-boron magnets are most commonly used because of their low cost, strong magnetic properties, corrosion resistance, and ease of cutting and shaping. Their biocompatibility can also be improved through coatings such as titanium nitride[11].

Magnet size varies according to the target anatomy and clinical application. Typical magnets measure approximately 4-12 mm in diameter and 5-10 mm in thickness. Ring magnets with a central hole allow passage of a guidewire or suture, facilitating endoscopic delivery. For example, 10 mm × 8 mm ring magnets have been used in patients with gastric outlet obstruction to align the stomach and duodenum. In biliary strictures (BBSs), 4 mm × 8 mm cylindrical magnets with a string looped through a side hole have been advanced into the bile ducts. Novel designs include deformable self-assembled magnetic anastomosis rings (DSAMARs), which are introduced in a linear configuration and subsequently assemble into a circular structure in situ. Magnet strength is selected on the basis of the anticipated tissue thickness, and compressive forces of several newtons are typically required to achieve necrosis of fibrotic tissue.

The contact surfaces of the magnets are designed to generate a variable magnetic force gradient, with a stronger magnetic field at the center and a weaker field at the periphery. This gradient creates differential pressure across the compressed tissue, resulting in ischemic necrosis at the center of the tissue interface while allowing the surrounding tissue to remodel. Thus, this design may reduce the risk of anastomotic complications and promote faster formation of a stable anastomosis[13,17,18]. Chen et al[19] reported that the diameter of the MCA device should exceed 120% of the enteric diameter to maintain the stability of the intestinal anastomosis. Additional studies are required to optimize magnet size and shape to accelerate anastomosis formation while reducing the risk of complications.

The diameter of the resulting anastomosis depends on both the properties of the magnets and the degree of tissue tension between them. Recent studies have highlighted the importance of tissue tension, demonstrating that high-tension conditions result in narrower anastomoses with greater collagen deposition. In a rat model, Zhang et al[20] demonstrated that high-tension magnetic anastomoses produced significantly narrower lumens and greater collagen deposition than low-tension anastomoses. Clinically, a greater distance between the magnets may increase tissue stretch and tension, which can ultimately result in a smaller final anastomotic diameter.

Delivery routes

The delivery approach depends on the location and anatomy of the stricture (Figures 2 and 3). In BBSs, the most commonly used technique is a dual endoscopic-percutaneous “rendezvous” approach, in which one magnet is introduced through percutaneous transhepatic biliary access and the other through endoscopic retrograde cholangiopancreatography or duodenoscopy. For the percutaneous approach, a percutaneous transhepatic biliary drainage tract is typically created, gradually dilated to 16 Fr, and subsequently exchanged for an 18-Fr sheath. A major advancement in biliary MCA is the development of through-the-scope micro-magnets that can be delivered through the working channel of the endoscope by using a pusher catheter. This technique may expand the feasibility of treating complete posttransplant duct-to-duct biliary occlusions when the distal duct is accessible endoscopically and the proximal duct is accessible percutaneously[21]. Interventional radiology plays a central role in percutaneous transhepatic biliary drainage access, tract maturation, controlled catheter exchange, and rescue strategies in patients with complex anatomy[5]. Magnets are usually delivered using a polypectomy snare, whereas newer wire-guided magnets can be deployed by simply withdrawing the guidewire[2]. In esophageal or gastric applications, magnets may be delivered through upper endoscopy, although previous surgical gastrostomy or jejunostomy can also provide access. In gastroenteric anastomosis, the distal magnet may be advanced into the ileum under combined laparoscopic and endoscopic guidance, whereas the proximal magnet is positioned endoscopically within the gastric antrum[22]. In colorectal applications, combined colonoscopic and percutaneous approaches have been described. Emerging techniques also include endoscopic ultrasound-guided magnet placement[18]. Fluoroscopic guidance is typically used throughout the procedure to confirm accurate alignment of the magnets. In patients with challenging anatomy, combined approaches, including laparoscopic assistance or balloon-anchor techniques, have also been reported[8].

Alignment and coupling

Accurate magnet alignment is critical for successful MCA. Under imaging guidance, the two magnets are brought into close apposition across the stricture or occluded segment. This process may require repeated adjustments; for example, in BBSs, operators may need to manipulate contrast catheters and guidewires repeatedly until both magnet carriers are positioned accurately at the opposite ends of the stricture. Once proper alignment is achieved, the magnets couple through mutual attraction, and gradual tissue compression begins. In several protocols, serial radiographs are obtained every 1-2 weeks to monitor magnet approximation and coupling. The time required to achieve complete magnetic coupling typically ranges from 1 week to 6 weeks, depending on tissue characteristics and stricture length. Shorter distances between the magnets and thinner tissue interfaces, such as those encountered in bilioenteric channels, are generally associated with faster coupling.

Retrieval and patency maintenance

After successful coupling, the magnets are either removed endoscopically or allowed to pass spontaneously through the gastrointestinal tract. In many biliary MCA protocols, the magnets are endoscopically retrieved approximately 4-8 weeks after placement once complete magnet coupling and tract formation have been achieved. In other cases, the magnets detach spontaneously and migrate distally, eventually being expelled per rectum. After the tract has formed, an indwelling stent or drainage catheter is usually placed to support fistula maturation and maintain luminal patency. The stent is subsequently removed after adequate maturation of the tract, and follow-up cholangiography or endoscopy is performed to confirm sustained patency of the anastomosis. When required, balloon dilation can be performed to further optimize the anastomotic diameter.

Experimental and animal studies

Preclinical studies have validated the biomechanical feasibility and safety of MCA. Comparative animal studies evaluating MCA against hand-sewn or stapled anastomoses have demonstrated that MCA-created anastomoses are comparable or superior to conventional techniques, with no severe adverse events or stenosis reported[23]. Early porcine studies have shown that magnetic anastomoses achieve burst strengths comparable to those of sutured anastomoses[23]. Kotlovsky et al[24] further reported that magnetic anastomoses in animal models demonstrated “seamless healing” and greater burst strength than conventional sutured anastomoses. Similarly, Pichakron et al[17] showed in a porcine model that magnamosis produces immediately patent anastomoses that subsequently develop mechanical strength equal to or greater than that of hand-sewn or stapled anastomoses.

Animal studies have demonstrated that MCA-created anastomoses heal with strong tissue continuity. Histological analyses have shown complete mucosal and serosal fusion, reduced inflammation, and relatively mild fibrosis compared with conventional techniques[23,25]. For example, in rats undergoing magnetic gastrojejunostomy, investigators observed improved healing with less granulation tissue formation and lower expression of transforming growth factor-β1 and hypoxia-inducible factor-1α than in rats undergoing sutured anastomosis[26]. Zhang et al[27] also demonstrated successful MCA in pigs using DSAMARs to create a gastrojejunal bypass. All 10 animals developed successful anastomoses without leakage or bleeding, and the magnets spontaneously passed within 10-17 days. Histological examination confirmed well-formed mucosal and serosal continuity at the anastomotic site.

CLINICAL APPLICATIONS

Biliary anastomosis

Bile duct injuries occur in up to 15%-40% of patients undergoing liver transplantation, 0.2%-0.3% of patients undergoing open cholecystectomy, and 0.3%-0.8% of patients undergoing laparoscopic cholecystectomy and may subsequently result in benign BBSs[28-30]. Endoscopic therapy is considered the first-line treatment for BBSs and achieves clinical success rates of approximately 80%-90%, particularly with the use of multiple plastic stents or fully covered self-expandable metal stents. However, stricture recurrence occurs in approximately 10%-30% of patients[31-33]. Endoscopic management is often unsuccessful in patients with completely obstructed or severely stenotic strictures or in those with bile duct deviation that prevents guidewire passage[3]. In these situations, MCA can be used to create a new choledochocholedochostomy by reconstructing the obstructed biliary segment (Figure 4)[3]. The major advantages of MCA are that it avoids major surgery and can achieve recanalization even when guidewire traversal is not possible. However, the procedure requires specialized equipment and technical expertise and is associated with a longer treatment course. A comparison of surgical, endoscopic, and MCA-based approaches for the management of BBSs is presented in Table 1. Unlike conventional stenting, which primarily dilates the stricture, MCA removes fibrotic tissue through pressure-induced necrosis[3].

Figure 4 Magnetic compression anastomosis for postcholecystectomy bile duct injury stricture. A: Percutaneous transhepatic cholangiogram showing complete cut off of common bile duct; B: Parent magnet being deployed by percutaneous trans hepatic route; C: Daughter magnet being delivered via endoscopic retrograde cholangiographic route; D: Both the magnet were kept in place by stents; E: After 10 days, magnets approximated and wire negotiated into intrahepatic biliary radicle via neo fistula; F: Cholangiogram demonstrating resolution of stricture and neo fistula.

Table 1 Comparison of surgical, endoscopic, and magnetic compression approaches.

Parameter	Surgical repair	Endoscopic/stenting	MCA
Invasiveness	High (open/laparoscopic)	Low-moderate (endoscopic)	Low-moderate (minimally invasive)
Immediate success rate	High (but not 100%)	Variable (depends on anatomy)	High (in selected cases)
Need for re-intervention	Moderate (strictures can recur)	High (stents need exchange, recurrent strictures)	Moderate (requires dilation and stenting post-MCA)
Technical difficulty	High (surgery/anastomosis)	Moderate (ERCP/PTBD)	High (new technique, device handling)
Patient risk	High (operative risk)	Low-moderate (infection, pancreatitis)	Low (mostly sedation/endoscopy risks)
Evidence base	Strong	Strong (RCTs, meta-analyses)	Weak (case series, early reports)

MCA: Magnetic compression anastomosis; ERCP: Endoscopic retrograde cholangiopancreatography; PTBD: Percutaneous transhepatic biliary drainage; RCTs: Randomized controlled trial.

Determinants of successful anastomosis: The success of biliary MCA depends on several anatomical and technical factors. Stricture etiology is a crucial determinant because MCA has demonstrated higher success rates in short benign strictures, particularly posttransplant anastomotic strictures, than in long-segment strictures or strictures associated with complex fibrosis[8]. Stricture length is another critical factor. Strictures shorter than approximately 5 mm are associated with a higher likelihood of technical success, whereas longer or completely obliterated segments reduce the likelihood of successful recanalization[8,10,21]. The compression force generated by the magnets is influenced by their size and magnetic strength and directly affects tissue necrosis and subsequent anastomosis formation. In addition, biliary anatomy and ductal alignment are critical because proper coaxial alignment of the magnets facilitates effective compression and fistula formation. Therefore, careful patient selection based on anatomical and procedural considerations is crucial for achieving optimal outcomes with MCA. However, currently available radiological imaging alone does not adequately assess all factors associated with procedural success. Additional evaluation using percutaneous cholangiography, endoscopic cholangiography, or cholangioscopy is often required to better define the anatomy and procedural feasibility.

In a case series by Li et al[10], nine patients with BBSs, most of which were posttransplant strictures with a mean stricture length of approximately 3 mm, underwent MCA. Successful recanalization was achieved in all nine patients, with a mean recanalization time of approximately 16 days, after which stents were placed to maintain ductal patency. Only two minor adverse events were reported: Cholangitis and mild bleeding. Long-term follow-up of up to 66 months demonstrated no restenosis in any patient. After MCA, temporary stent placement is commonly performed to maintain patency during tract maturation, and both plastic stents and fully covered self-expandable metal stents have been used. In a case report by Do et al[34], a fully covered self-expandable metal stent was placed after MCA and exchanged at 3-week intervals following cholangiographic assessment, resulting in complete stricture resolution after 6 months. Postprocedural surveillance after MCA is crucial for the early detection and management of restenosis. Most protocols include scheduled imaging studies or cholangiography after stent removal to confirm sustained patency. The clinical outcomes and success rates of MCA reported in studies of benign BBSs are summarized in Table 2[2,10,12,21,35-40].

Table 2 Summary of clinical studies evaluating magnetic compression anastomosis for biliary conditions.

Ref.	Country	Design and patients	Indication	Main outcome	Adverse events and limitations
Jang et al[35], 2011	South Korea	Retrospective observational study; n = 12	Biliary anastomotic strictures after living donor liver transplantation	Successful recanalization of biliary anastomotic stricture after LDLT. Clinical success: 9/12 (75%); technical success: 10/12 (83.3%)	Mild cholangitis (n = 1); recurrence of anastomotic stricture (n = 1)
Jang et al[36], 2014	South Korea	Retrospective case series; n = 7	Recanalization of refractory benign biliary strictures	Successful recanalization of completely obstructed benign biliary strictures. Clinical success: 5/7 (71.4%); technical success: 5/7 (71.4%)	No MCA-related complications or restenosis reported
Ersoz et al[37], 2016	Turkey	Pilot study/case series; n = 6	Disconnected bile duct after living-donor liver transplantation	Biliary recanalization after magnetic compression anastomosis. Clinical success: 6/6 (100%); technical success: 6/6 (100%)	No procedure-related adverse events reported
Jang et al[2], 2017	South Korea	Single-center retrospective cohort study; n = 39	Completely obstructed benign biliary strictures	Successful recanalization and long-term patency of the biliary tract. Clinical success: 33/39 (84.6%); technical success: 35/39 (89.7%)	Mild cholangitis (n = 1); restenosis (n = 1); partial restenosis (n = 1)
Parlak et al[21], 2017	Turkey	Prospective case series; n = 9	Complete biliary obstruction after liver transplantation	Recanalization of complete duct-to-duct biliary anastomosis obstruction. Clinical success: 7/9 (77.8%); technical success: 7/9 (77.8%)	No procedure-related adverse events
Li et al[10], 2020	China	Prospective single-center clinical study; n = 9	Benign biliary strictures	Successful recanalization of benign biliary stricture with sustained duct patency. Clinical success: 9/9 (100%); technical success: 9/9 (100%)	Mild cholangitis (n = 1); biliary bleeding from PTBD tract (n = 1)
Ödemiş et al[12], 2022	Turkey	Retrospective case series; n = 19	Completely obstructed benign biliary strictures	Recanalization of completely obstructed benign biliary strictures with restoration of bile flow. Clinical success: 12/19 (63.2%); technical success: 19/21 procedures (90.5%)	Magnet entrapment (n = 3); magnet migration (n = 2); cholangitis (n = 1)
Chavan et al[38], 2024	India	Case series; n = 3	Post-cholecystectomy benign biliary stricture recanalization	Bile duct recanalization confirmed by cholangiography after magnet removal. Clinical success: 3/3 (100%); technical success: 3/3 (100%)	None reported
Jang et al[39], 2024	South Korea	Retrospective cohort study; n = 10	Complete biliary obstruction after cholecystectomy	Recanalization of complete biliary obstruction with creation of a fistulous tract. Clinical success: 8/10 (80%); technical success: 10/10 (100%)	No procedure-related adverse events; 2 patients developed stricture recurrence treated with repeat FCSEMS
Ünal et al[40], 2025	Turkey	Retrospective single-center cohort study; n = 26	Post-transplant biliary strictures (combined endoscopic-percutaneous approach)	Successful recanalization of completely obstructed post-transplant biliary anastomotic strictures with long-term patency. Clinical success: 24/26 (92.3%); technical success: 24/26 (92.3%)	Recurrent biliary stricture during follow-up (n = 6); no major procedure-related complications reported

FCSEMS: Fully covered self-expandable metal stent; LDLT: Living donor liver transplantation; MCA: Magnetic compression anastomosis; PTBD: Percutaneous transhepatic biliary drainage.

Bilioenteric anastomosis

Bilioenteric anastomotic strictures are most commonly encountered after Roux-en-Y bilioenteric reconstruction. Magnet delivery in these strictures can be achieved through several approaches, including a percutaneous-peroral route using a forward-viewing endoscope, similar to the approach used in biliobiliary MCA; a surgically created percutaneous-enteric tract; or a combined percutaneous-percutaneous approach[8]. Single-balloon enteroscopy is particularly useful in patients with long or redundant afferent loops that cannot be accessed using a conventional forward-viewing endoscope[4]. In patients with separate right and left hepatoenteric anastomoses, two independent percutaneous cholangioscopic approaches may be required to access each biliary-enteric anastomosis separately.

The distance between the magnets in bilioenteric anastomoses is generally shorter (approximately 2-7 mm) than that in biliobiliary anastomoses (approximately 2-15 mm). This shorter distance allows stronger magnetic compression and more effective tissue necrosis. Thus, complete magnet approximation occurs more rapidly in bilioenteric strictures, typically within 7-40 days, whereas the mean approximation time in biliobiliary strictures is approximately 53.3 days[8]. Previous studies and case series have reported favorable outcomes with MCA in bilioenteric strictures, with few severe complications, supporting the safety and efficacy of this technique in carefully selected patients[8]. The outcomes of MCA reported in clinical studies of bilioenteric anastomotic strictures are summarized in Table 3[41-46].

Table 3 Summary of clinical studies evaluating magnetic compression anastomosis for biliary-enteric conditions.

Ref.	Country	Design and patients	Indication	Main outcome	Adverse events and limitations
Liu et al[41], 2018	China	Prospective clinical trial; n = 41	Biliojejunostomy	Successful formation of bilioenteric anastomosis with long-term patency. Clinical success: 39/41 (95.1%); technical success: 41/41 (100%)	Cholangitis before magnet expulsion (n = 3); biliary anastomotic stricture requiring reoperation (n = 2)
Liu et al[42], 2019	China	Prospective case series; n = 5	Laparoscopic magnetic compression biliojejunostomy for obstructive jaundice	Formation of patent biliojejunostomy with successful internal biliary drainage. Clinical success: 5/5 (100%); technical success: 5/5 (100%)	Wound infection (n = 1); no anastomotic leak or stricture
Liu et al[43], 2019	China	Prospective case series; n = 4	Biliojejunostomy and pancreaticojejunostomy during Whipple’s procedure	Formation of functional biliojejunostomy and pancreaticojejunostomy after pancreaticoduodenectomy. Clinical success: 3/4 (75%); technical success: 4/4 (100%)	Cholangitis (n = 1); pancreatic fistula (n = 1); biliary anastomotic stricture at 11 months (n = 1)
Li et al[44], 2021	China	Retrospective case series; n = 7	Magnetic compression anastomosis during laparoscopic pancreatoduodenectomy for choledochojejunostomy and pancreatojejunostomy	Formation and postoperative function of magnetic biliojejunostomy and pancreaticojejunostomy after laparoscopic pancreatoduodenectomy. Clinical success: 7/7 (100%); technical success: 7/7 (100%)	Pancreatic fistula (n = 2); intra-abdominal infection (n = 2); delayed gastric emptying (n = 2); intra-abdominal bleeding (n = 1); no biliary or pancreatic anastomotic leak
Li et al[45], 2021	China	Prospective clinical study; n = 23	Cholangiojejunostomy	Restoration of biliary drainage through magnetic compression cholangiojejunostomy. Clinical success: 22/23 (95.7%); technical success: 23/23 (100%)	Bile leakage (n = 1); postoperative complications (Clavien-Dindo I-IIIa) in 10 patients; cholangitis during follow-up (n = 3); anastomotic stricture (n = 1)
Avaliani et al[46], 2009	Russia	Prospective clinical series; n = 34	Palliation of malignant obstructive jaundice	Creation of biliary-enteric fistula for internal biliary drainage in malignant obstructive jaundice. Clinical success: 29/34 (85.3%); technical success: 34/34 (100%)	Temporary occlusion of bypass due to food debris (n = 2); tumor ingrowth requiring surgical revision (n = 3); reflux cholangitis (n = 2)

Esophageal anastomosis

One of the most common indications for MCA is congenital or refractory strictures of the esophagus or stomach, particularly long-gap EA in infants. In clinical practice, MCA is generally considered in patients with EA when thoracoscopic repair is associated with a high operative risk. A pioneering study by Zaritzky et al[47] demonstrated the technical feasibility of MCA in patients with EA. In this study, the proximal magnet was delivered endoscopically, whereas the distal magnet was introduced through gastroscopy. The study included patients with type A EA and an esophageal gap length of < 3 cm. Anastomosis was successfully achieved in all patients within a mean duration of 4.8 days; however, all patients subsequently developed restenosis[47]. The high rate of restenosis has been attributed to excessive tension across the anastomotic site. To address this limitation, newer approaches have combined staged esophageal pouch-lengthening procedures with specially designed magnetic devices to reduce anastomotic tension and improve long-term patency[48].

A systematic review by Holler et al[49] reported that newer bi-radial magnet designs were associated with fewer postoperative dilations than the original ring-shaped magnets (4-5 dilations vs 9 dilations). Nevertheless, in the pooled cohort of 23 children who underwent MCA for EA, esophageal continuity was successfully established in nearly all cases. Nevertheless, the EA literature should be interpreted cautiously: Although continuity was established in nearly all reported children, anastomotic stricture formation was near universal and repeated dilation was commonly required. Thus, in EA, MCA should not be presented as a low-burden definitive therapy; rather, it is a reconstructive option that may avoid repeat thoracotomy in selected patients but often substitutes surgical risk with a prolonged endoscopic follow-up and dilation burden[49]. The outcomes of MCA reported in clinical studies of esophageal strictures are summarized in Table 4[47,50-53].

Table 4 Summary of clinical studies evaluating magnetic compression anastomosis for esophageal conditions.

Ref.	Country	Design and patients	Indication	Main outcome	Adverse events and limitations
Zaritzky et al[47], 2009	Argentina	Prospective; n = 5	Esophageal atresia	Successful formation of an esophageal anastomosis. Clinical success: 100%; technical success: 80%	Restenosis in 80% requiring dilatation and Fever in one patient
Slater et al[50], 2019	United States	Multicenter retrospective case series; n = 13	Long-gap esophageal atresia	Establishment of esophageal continuity and long-term preservation of native esophagus. Clinical success: 12/13 (92.3%); technical success: 13/13 (100%)	Esophageal stricture requiring dilation in all patients (mean 9.8 dilations); stent placement (n = 6); surgery for refractory stricture (n = 2); perforation after dilation (n = 1)
Shieh et al[51], 2022	United States	Retrospective case series; n = 3	Long-gap esophageal atresia	Establishment of esophageal continuity and long-term. Clinical success: 0/3 (0%); technical success: 3/3 (100%)	Failure of anastomosis in 2 patients; magnet erosion into lung requiring surgery (n = 1); severe anastomotic stricture after repeat magnamosis (n = 1)
Conforti et al[52], 2023	Italy	Case series; n = 5	Long-gap esophageal atresia	Restoration of esophageal continuity. Clinical success: 5/5 (100%); technical success: 5/5 (100%)	Anastomotic stenosis requiring dilation (5/5); esophageal perforation after dilation (n = 1)
Lee et al[53], 2024	Germany, United States	First-in-human case series; n = 10	Esophageal magnetic compression anastomosis using the connect-EA device for esophageal atresia repair	Restoration of esophageal continuity and tolerance of oral feeding. Clinical success: 7/10 (70%); technical success: 9/10 (90%)	Bronchoesophageal fistula (n = 1); esophageal perforation after balloon dilation (n = 2)

EA: Esophageal atresia.

Determinants of failure of esophageal MCA: The primary cause of failure and restenosis in esophageal compression anastomosis (MCA) is excessive tissue tension, which increases collagen deposition and narrows anastomosis. The key contributing factors include: (1) Magnet distance: Larger gaps (e.g., in long-gap EA) increase tissue stretch and the risk of stricture; (2) Magnet design: Traditional ring magnets require more postoperative dilations to manage strictures than newer bi-radial designs; and (3) Anatomical challenges: Incorrect alignment or long-occluded segments often lead to technical failure.

Upper gastrointestinal anastomosis

MCA has also been investigated as an experimental treatment for gastric outlet obstruction. In an early clinical series, Chopita et al[54] reported a technical success rate of 86.6% (13/15 patients) for magnetic compression gastroenterostomy in patients with benign gastric outlet obstruction. In this study, anastomosis formation generally occurred within 7-14 days after magnet placement. Reported complications included anastomotic narrowing requiring balloon dilation, technical failure resulting from incomplete magnet coupling, and occasional magnet displacement. However, no major adverse events were reported in any patient.

Gomes et al[55] also demonstrated the feasibility of MCA for creating anastomoses in patients with gastric outlet obstruction caused by caustic injury. In this study, ring magnets were used to bypass the obstructed segment and create a gastrojejunostomy anastomosis. Magnet coupling occurred over approximately 10 days, after which the anastomosis was successfully established. However, serial balloon dilations were required to achieve a stable luminal diameter, with six dilation sessions performed to expand the anastomosis to 18 mm over a 6-week period. A prospective multicenter cohort study subsequently evaluated MCA in patients with malignant obstruction. However, the study was terminated early because of a serious adverse event involving stent-related perforation and a high rate of stent migration, highlighting the importance of device design and system selection in MCA procedures[56].

MCA has emerged as a minimally invasive alternative to conventional bariatric surgery. Using paired magnets delivered endoscopically, this technique creates a side-to-side enteroenteric anastomosis, thereby establishing a dual-path enteral bypass without surgical stapling or external incisions. Early clinical studies evaluating incisionless magnetic anastomosis systems have demonstrated significant weight loss and improved glycemic control in patients with obesity and type 2 diabetes. Machytka et al[57] reported that partial jejunal diversion using an incisionless magnetic anastomosis system achieved durable anastomotic patency at 1-year follow-up without any device-related serious adverse events. The procedure is typically performed endoscopically, with magnets positioned across adjacent bowel loops, after which the magnets detach spontaneously following successful anastomosis formation.

Colorectal anastomosis

The use of MCA in colorectal applications is gradually increasing. Reported indications include postoperative anastomotic strictures following colorectal surgery and benign sigmoid stenosis. Although experience in adult colorectal disease remains limited primarily to case reports and small case series, these reports demonstrate the feasibility of MCA as a minimally invasive salvage therapy for postoperative anastomotic stenosis[58,59]. Zhang et al[60] described a 53-year-old patient with a diverting colostomy for sigmoid obstruction who underwent MCA across a sigmoid stricture. Recanalization was achieved within 15 days, and the colostomy was successfully reversed 10 days later. No recurrent symptoms were observed during 13 months of follow-up. In another report, Zhang et al[59] described successful treatment of a postoperative rectal stricture using MCA. The magnets were placed endoscopically and expelled spontaneously after 16 days, and follow-up evaluation demonstrated a well-healed anastomosis that allowed subsequent ileostomy closure. Both reports concluded that combined endoscopic magnetic compression techniques may provide a minimally invasive treatment option for refractory rectal stenosis. MCA has also been successfully used in pediatric rectal atresia. In one case of necrotizing enterocolitis-associated rectal atresia, successful cecorectal MCA was achieved, with magnet coupling occurring by day 9 and spontaneous passage of the magnets per rectum. At 7-month follow-up, the patient demonstrated normal bowel function without evidence of recurrent stricture[61]. Russell et al[62] similarly reported successful MCA repair in rectal atresia. Potential challenges in colorectal MCA include higher tissue tension and lower bowel flexibility than in upper gastrointestinal applications. Nevertheless, early clinical reports suggest that MCA is technically feasible in the lower gastrointestinal tract. A summary of selected clinical studies evaluating MCA in intestinal and colorectal conditions is presented in Table 5[13,22,57,63-70].

Table 5 Summary of clinical studies evaluating magnetic compression anastomosis for intestinal and colorectal conditions.

Ref.	Country	Design and patients	Indication	Main outcome	Adverse events and limitations
Graves et al[13], 2017	United States	Prospective single-center first-in-human pilot study; n = 5	Small bowel anastomosis during open reconstructive surgery	Formation of functional small bowel anastomosis without leak, bleeding, or stricture. Clinical success: 5/5 (100%); technical success: 5/5 (100%)	No anastomosis-related complications; unrelated complications included aspiration pneumonia, internal hernia, Clostridium difficile infection, and superficial surgical site infection
Kamada et al[63], 2021	Japan	Retrospective single-center case series; n = 14	Gastrointestinal obstruction (without general anesthesia)	Creation of functional gastrointestinal anastomosis to relieve obstruction. Clinical success: 11/14 (78.6%); technical success: 14/14 (100%)	Restenosis (n = 2); anastomotic perforation due to balloon dilation (n = 1)
Gagner et al[64], 2023	Georgia	Prospective first-in-human observational study; n = 5	Side-to-side magnetic compression duodeno-ileostomy with sleeve gastrectomy for obesity and type 2 diabetes	Successful creation of patent duodeno-ileal anastomosis with magnet expulsion without reintervention. Clinical success: 5/5 (100%); technical success: 5/5 (100%)	No device-related adverse events; mild abdominal wound pain (n = 3), mucosal tear during endoscopy (n = 1), intra-abdominal hematoma (n = 1), ileal serosal tear (n = 1)
Gagner et al[65], 2023	Belgium, Spain, Georgia	Prospective multicenter observational study; n = 24	Side-to-side magnetic duodeno-ileostomy with sleeve gastrectomy for obesity and type 2 diabetes	Successful magnet placement with formation of patent duodeno-ileal anastomosis and spontaneous magnet expulsion. Clinical success: 24/24 (100%); technical success: 24/24 (100%)	3 procedure-related serious adverse events; no device-related adverse events, no anastomotic leak, bleeding, obstruction, infection, or mortality
Cadière et al[66], 2024	Belgium	Prospective observational study; n = 10	Side-to-side duodeno-ileal bipartition with sleeve gastrectomy	Patent duodeno-ileal anastomosis confirmed endoscopically at 1 year. Clinical success: 9/9 evaluated (100%); technical success: 10/10 (100%)	Serosal tears (n = 2), sleeve leak (n = 1), dehydration (n = 3), internal hernia (n = 1); no device-related AEs
Gagner et al[22], 2025	Canada, Belgium, Spain, Georgia	Prospective multicenter study; n = 43	Side-to-side magnetic duodeno-ileostomy with or without sleeve gastrectomy for severe obesity	Successful magnet positioning, formation of patent duodeno-ileal anastomosis, and spontaneous magnet passage. Clinical success: 43/43 (100%); technical success: 43/43 (100%)	No device-related adverse events, leaks, bleeding, obstruction, infection, or death
Gagner et al[67], 2024	Belgium	Prospective single-center study; n = 24	Revisional side-to-side magnetic duodeno-ileostomy after sleeve gastrectomy for severe obesity	Formation of patent duodeno-ileal anastomosis with spontaneous magnet expulsion and no need for reintervention. Clinical success: 24/24 (100%); technical success: 24/24 (100%)	8 SAEs (Clavien-Dindo II-III) but none related to device or procedure; no leak, bleeding, obstruction, infection, or death
Gagner et al[68], 2024	Belgium	Prospective single-center first-in-human study; n = 7	Gastroileostomy for revision of sleeve gastrectomy	Successful placement and alignment of magnets with patent gastroileal anastomosis and spontaneous magnet expulsion. Clinical success: 7/7 (100%); technical success: 7/7 (100%)	3 serious adverse events (Clavien-Dindo III anal fissure/hemorrhoids in 1 patient); no device-related adverse events, leaks, bleeding, obstruction, infection, or death
Gagner et al[69], 2025	Czech Republic	Prospective first-in-human observational study; n = 9	Jejuno-ileostomy bipartition for obesity and type 2 diabetes	Successful magnet alignment and formation of patent jejuno-ileal anastomosis with spontaneous magnet expulsion. Clinical success: 9/9 (100%); technical success: 9/9 (100%)	No severe adverse events; minor events included influenza after discharge and transient hypoglycemia after magnet expulsion
Bhandari et al[70], 2026	India, Chile	Prospective multicenter study; n = 14	Jejuno-jejunal anastomosis in Roux-en-Y gastric bypass	Freedom from anastomotic adverse events within 30 days. Clinical success: 14/14 (100%); technical success: 14/14 (100%)	Procedure-related AEs: Bleeding, dysphagia, pulmonary embolism, diabetic ketoacidosis (n = 4); no device-related AEs
Machytka et al[57], 2017	Czech Republic	Prospective single center study; n = 10	Partial jejunal diversion	Total weight loss. Clinical success: 100%; technical success: 100%	No Serious, trocar-related gastric injury in one patient

AE: Adverse event; SAE: Serious adverse event.

Evidence quality and complications

Across different clinical indications, MCA has demonstrated high technical and clinical success rates in carefully selected patients. However, the available evidence remains limited because randomized controlled trials and large prospective cohorts are lacking. Most published data are derived from case reports and small case series, and therefore potential publication bias, the absence of control groups, and heterogeneity in patient populations and procedural techniques must be considered when interpreting the reported outcomes. Additional limitations include the potentially steep learning curve associated with the procedure, limited availability of specialized magnetic devices, and the requirement for a multidisciplinary team involving endoscopists, interventional radiologists, and surgeons. At present, MCA is primarily considered a salvage technique for patients in whom conventional therapeutic approaches have failed. Future reports should use standardized definitions, capture all re-interventions, report denominator-based adverse events, and provide durable follow-up beyond initial tract creation.

MCA appears to have an acceptable safety profile, and treatment-related mortality has not been reported to date. Technical failure most commonly results from failure of magnet approximation or incorrect alignment, particularly in patients with long occluded segments, multiple strictures, or unfavorable anatomical geometry[5]. Reported complications in biliobiliary anastomosis include cholangitis and bleeding, which are generally managed conservatively[3]. Several case reports have also described magnet migration leading to failed magnet retrieval, hemorrhage, or perforation (Figure 5)[8,63,71]. Available evidence suggests that MCA-created anastomoses can achieve durable long-term patency when the tract is adequately maintained during healing, typically with temporary stenting. However, restenosis remains a significant concern, particularly in high-tension regions, and may require balloon dilation or repeat intervention[2,35].

Figure 5 Magnet migration and failed magnetic compression anastomosis. A: Percutaneous cholangiogram showing complete cut of the bile duct; B: Both parent and daughter magnets deployed, however, the distance between them is long (4 cm); C: Serial radiograph showed no anastomosis formation; D: Distal magnet was retrieved endoscopically; however, cholangioscopic retrieval of the magnet failed, and the patient underwent surgery.

Future directions

Several aspects of MCA remain experimental. Currently, there is no standardized optimal magnet design, size, or coating. In addition, certain anatomical situations, particularly extremely long or tortuous strictures, may not be suitable for this technique. Another recognized limitation is the tension-dependent nature of MCA, which often necessitates post-anastomotic balloon dilation to maintain adequate luminal patency. From a clinical perspective, the absence of large prospective trials and multicenter registries limits the current understanding of long-term outcomes and prevents accurate identification of the patient populations most likely to benefit from MCA. Therefore, future research should focus on prospective registries and controlled comparative studies evaluating MCA against conventional surgical and endoscopic treatments.

Innovative device designs, including biodegradable magnets and sensor-embedded magnetic systems, are currently being developed to improve the safety and functionality of MCA. The DSAMAR concept may further expand the feasibility of fully endoscopic deployment in narrow luminal structures. In addition, wider adoption of MCA will require dedicated procedural training and greater multicenter collaboration to standardize techniques and improve outcome assessment. Regulatory guidance for MCA devices and procedures will also continue to evolve as clinical experience increases across more centers. Overall, MCA represents a promising area of minimally invasive gastrointestinal intervention; however, its definitive clinical role will become clearer only through further high-quality research.

CONCLUSION

MCA is evolving from an experimental concept into a practical salvage technique for restoring gastrointestinal or biliary continuity when conventional therapies fail. Available animal studies and clinical case series suggest that MCA can achieve high technical success rates with an acceptable safety profile and can produce well-healed anastomoses. Clinical outcomes appear most favorable in patients with short strictures, predictable anatomical alignment, and structured post-recanalization management with temporary stenting. Outside biliary applications, the available evidence remains limited and heterogeneous, and procedural outcomes are strongly influenced by magnet design and the use of adjunctive devices. Therefore, additional prospective studies, further device refinement, and long-term follow-up data are required before MCA can be recommended for widespread clinical use.