BACKGROUND: The combination of magnetic compression anastomosis (MCA) and endoscopy has been used to treat biliary stricture after liver transplantation. However, its use for the treatment of complex biliary obstruction after major abdominal trauma has not been reported. This case report describes the successful use of MCA for the treatment of biliary obstruction resulting from major abdominal trauma.
METHODS: A 23-year-old man underwent major abdominal surgery (repair of liver rupture, right half colon resection, and ileostomy) following a car accident one year ago. The abdominal drainage tube, positioned at the Winslow foramen, was draining approximately 600-800 mL of bile per day. During the two endoscopic retrograde cholangiopancreatography procedures, the guide wire was unable to enter the common bile duct, which prevented placement of a biliary stent. MCA combined with endoscopy was used to successfully achieve magnetic anastomosis of the peritoneal sinus tract and duodenum, and then a choledochoduodenal stent was placed. Finally, the external biliary drainage tube was removed. The patient achieved internal biliary drainage leading to the removal of the external biliary drainage tube, which improved the quality of life.
CONCLUSIONS: Magnetic compression technique can be used for the treatment of complex biliary obstruction with minimal operative trauma.

With the increasing application of magnetic compression anastomosis (MCA) in gastrointestinal anastomosis, we identified an interesting phenomenon that an anastomosis is more prone to stenosis after endoscopic gastrointestinal MCA. We hypothesized that the increase in tissue tension during endoscopic procedures is the cause of anastomotic stenosis. In this study, we investigated the effect of tissue tension on gastroduodenal bypass MCA in Sprague-Dawley (SD) rats. Twenty SD rats were divided into the study group (high-tension group, n = 10) and control group (no tension group, n = 10), wherein the rats underwent complete gastroduodenal bypass magnetic anastomosis under high tension and no tension of the digestive tract, respectively. Anastomotic specimens were obtained 4 weeks after the operation, and anastomotic diameters of the two groups were observed and measured. The histological difference was observed by hematoxylin & eosin and Masson staining. The operation was successfully completed in all rats, and all survived until 4 weeks postoperatively. Anastomotic measurements revealed that the anastomosis diameter was significantly smaller in the study group than in the control group, and there were three cases of severe anastomotic stenosis. Histological observation showed that the amount of collagen fibers in the anastomosis was greater in the study group than in the control group. The results suggest that the high-tension state of the digestive tract is an important factor leading to anastomotic stenosis, and thus, we put forward the Yan-Zhang\'s Tissue Tension Theory of MCA to explain this phenomenon.

Obstructions encountered in biliary, gastrointestinal, and urinary tracts are increasing in number due to successful percutaneous and endoscopic organ-saving procedures. Although functional recovery is established to an extent, failure of traversing an obstruction may end up necessitating invasive surgical procedures. Multidisciplinary collaboration may traverse the limitations of each individual approach, therefore creating the perfect intervention for the patient. Magnetic compression anastomosis is a minimally invasive procedure that can provide a great outcome in select cases with biliary, gastrointestinal, or urinary tract obstructions. CRITICAL RELEVANCE STATEMENT: In this article, various applications of magnetic compression anastomosis are reviewed with illustrative cases of esophageal, biliary, colonic, and urinary obstructions that cannot be traversed with a wire. This method will expand the spectrum of interventions performed in the IR unit. KEY POINTS: Magnets can enable wire access beyond an impassable obstruction. Magnets can create anatomical and non-anatomical anastomosis at an occlusion. Magnetic compression anastomosis is a minimally invasive procedure that can provide great outcomes.

Although the application of magnetic compression anastomosis is becoming increasingly widespread, the magnets used in earlier studies were mostly in the shape of a whole ring. Hence, a deformable self-assembled magnetic anastomosis ring (DSAMAR) was designed in this study for gastrointestinal anastomosis. Furthermore, its feasibility was studied using a beagle model. The designed DSAMAR comprised 10 trapezoidal magnetic units. Twelve beagles were used as animal models, and DSAMARs were inserted into the stomach and colon through the mouth and anus, respectively, via endoscopy to achieve gastrocolic magnamosis. Surgical time, number of failed deformations, survival rate of the animals, and the time of magnet discharge were documented. A month later, specimens of the anastomosis were obtained and observed with the naked eye as well as microscopically. In the gastrocolic anastomosis of the 12 beagles, the procedure took 65-120 min. Although a deformation failure occurred during the operation in one of the beagles, it was successful after repositioning. The anastomosis was formed after the magnet fell off 12-18 days after the operation. Naked eye and microscopic observations revealed that the anastomotic specimens obtained 1 month later were well-formed, smooth, and flat. DSAMAR is thus feasible for gastrointestinal anastomosis under full endoscopy via the natural orifice.

BACKGROUND: Despite much work having been conducted on magnetic compression anastomosis (MCA) in the digestive tract, there are no reports on the influence of magnetic force on the anastomosis.
OBJECTIVE: To investigate the effect of different magnetic force magnets on the MCA of the digestive tract.
METHODS: Two groups of magnets of the same sizes but different magnetic forces were designed and produced. A total of 24 Sprague-Dawley rats were randomly assigned into two groups (powerful magnet group and common magnet group), with 12 rats in each group. Two types of magnets were used to complete the colonic side-to-side anastomosis of the rats. The operation time and magnet discharge time were recorded. The anastomotic specimens were obtained 4 wk after the operation and then the burst pressure and diameter of the anastomosis were measured, and the anastomosis was observed via the naked eye and subjected to histological examination.
RESULTS: The magnetic forces of the powerful and common magnet groups at zero distance were 8.26 N and 4.10 N, respectively. The colonic side-to-side anastomosis was completed in all 24 rats, and the operation success rate and postoperative survival rate were 100%. No significant difference was noted in the operation time between the two groups. The magnet discharge time of the powerful magnet group was slightly longer than that of the common magnet group, but the difference was not statistically significant (P = 0.513). Furthermore, there was no statistical difference in the burst pressure (P = 0.266) or diameter of magnetic anastomosis (P = 0.095) between the two groups. The gross specimens of the two groups showed good anastomotic healing, and histological observation indicated good mucosal continuity without differences on healing.
CONCLUSIONS: In the rat colonic side-to-side MCA model, both the powerful magnet with 8.26 N and the common magnet with 4.10 N showed no significant impact on the anastomosis establishment process or its effect.

BACKGROUND: Esophageal atresia (EA) is a life-threatening congenital malformation in newborns, and the traditional repair approaches pose technical challenges and are extremely invasive. Therefore, surgeons have been actively investigating new minimally invasive techniques to address this issue. Magnetic compression anastomosis has been reported in several studies for its potential in repairing EA. In this paper, the primary repair of EA with magnetic compression anastomosis under thoracoscopy was reported.
METHODS: A full-term male weighing 3500 g was diagnosed with EA gross type C. The magnetic devices used in this procedure consisted of two magnetic rings and several catheters. Tracheoesophageal fistula ligation and two purse strings were performed. The magnetic compression anastomosis was then completed thoracoscopically. After the primary repair, no additional operation was conducted. A patent anastomosis was observed on the 15th day postoperatively, and the magnets were removed on the 23rd day. No leakage existed when the transoral feeding started.
CONCLUSIONS: Thoracoscopic magnetic compression anastomosis may be a promising minimally invasive approach for repairing EA.

BACKGROUND: Endoscopic balloon dilation is a minimally invasive treatment for colorectal stenosis. Magnetic compression anastomosis can be applied against gastrointestinal anastomosis. When combined with endoscopy, it offers a unique approach to the recanalization of colorectal stenosis.
METHODS: We have reported here the case of a 53-year-old female patient who underwent a descending colostomy due to sigmoid obstruction. Postoperative fistula restoration was not possible in her due to sigmoid stenosis. Accordingly, endoscopic-assisted magnetic compression anastomosis for sigmoid stenosis was performed, and the sigmoid stenosis was recanalized 15 d after the surgery. Subsequently, a reduction colostomy was successfully performed after 10 d.
CONCLUSIONS: This case report proposes a novel minimally invasive treatment approach for colorectal stenosis.

Originating in the 1970s, magnetic compression anastomosis (MCA) has lately been revisited with a focus on minimal invasive surgery (MIS). The aim of this report is to reappraise our earlier experience with MCA with the intention of facilitating future MCA advancement. A retrospective review was conducted regarding preclinical experiments and clinical trials at a single institution from 1980 to 1995. The reviewed information was compiled and appraised to generate proposals for future MCA use. The experimental studies, including 250 MCA cases in gastrointestinal and urinary tract animal models, demonstrated the technical versatility of MCA as well as the superior biomechanical characteristics in comparison to hand-sewn anastomoses. Clinical trials encompassed 87 MCA procedures in 86 children, 2 to 10 years of age, involving the following techniques: non-operative esophageal recanalization (n = 15), non-operative ileostomy undiversion (n = 46), Swenson pull-through (n = 10), non-operative urethral recanalization (n = 5), and extravesical ureterocystoneostomy (n = 11). Clinical MCA was found to be successful in over 87% of cases. MCA limitations concerning anastomotic failure and scarring were thought to be mostly due to inadequate magnetic compression. Based on our historic experience, we propose further research on the technical aspects of MCA, along with the biological aspects of anastomotic tissue remodeling. Magnets should be designed and manufactured for a wide spectrum of pediatric surgical indications, particularly in combination with novel MIS techniques.

BACKGROUND: Magnetic compression anastomosis (MCA) is a simple procedure contributing to a reliable anastomosis. However, digestive-tract reconstruction after total gastrectomy using MCA has not yet been reported.
OBJECTIVE: To investigate the feasibility of MCA for simultaneous esophagojejunostomy and jejunojejunostomy after total gastrectomy using beagle dogs.
METHODS: Sixteen beagles were randomly divided into an MCA group (study group, n = 8) and a manual-suture anastomosis group (control group, n = 8). Two different magnetic anastomosis devices were used in the study group for esophagojejunal and jejunojejunal anastomoses. Both devices included a pair of circular daughter and parent magnets each. The time of esophagojejunostomy and jejunojejunostomy, postoperative complications, and survival rate of the two groups were compared. The dogs were sacrificed one month after the operation and their anastomotic specimens were obtained. Healing was observed by the naked eye and a light microscope.
RESULTS: Digestive-tract reconstruction after total gastrectomy was successfully completed in both groups (survival rate = 100%). In the study group, esophagojejunal and jejunojejunal anastomoses took 6.13 ± 0.58 and 4.06 ± 0.42 min, respectively, significantly lower than those in the control group (15.63 ± 1.53 min, P < 0.001 and 10.31 ± 1.07 min, P < 0.001, respectively). Complications such as bleeding, anastomotic leakage, and anastomotic stenosis were not observed. In the study group, the magnets did not interfere with each other. Discharge time of the jejunojejunal magnetic anastomosis device was 10.75 ± 1.28 d, while that of the esophagojejunal magnetic anastomosis device was 12.25 ± 1.49 d. Residual silk was found in the control group. The study group showed a greater smoothness of the anastomosis than that of the control group. All layers of anastomosis healed well in both groups.
CONCLUSIONS: MCA is a safe and feasible procedure for digestive-tract reconstruction after total gastrectomy in this animal model.

Gastrointestinal anastomoses with classical sutures and/or metal staples have resulted in significant bleeding and leak rates. This multi-site study evaluated the feasibility, safety, and preliminary effectiveness of a novel linear magnetic compression anastomosis device, the Magnet System (MS), to form a side-to-side duodeno-ileostomy (DI) diversion for weight loss and type 2 diabetes (T2D) resolution.
In patients with class II and III obesity (body mass index [BMI, kg/m2] ≥ 35.0- ≤ 50.0 with/without T2D [HbA1C > 6.5%]), two linear MS magnets were delivered endoscopically to the duodenum and ileum with laparoscopic assistance and aligned, initiating DI; sleeve gastrectomy (SG) was added. There were no bowel incisions or retained sutures/staples. Fused magnets were expelled naturally. Adverse events (AEs) were graded by Clavien-Dindo Classification (CDC).
Between November 22, 2021 and July 18, 2022, 24 patients (83.3% female, mean ± SEM weight 121.9 ± 3.3 kg, BMI 44.4 ± 0.8) in three centers underwent magnetic DI. Magnets were expelled at a median 48.5 days. Respective mean BMI, total weight loss, and excess weight loss at 6 months (n = 24): 32.0 ± 0.8, 28.1 ± 1.0%, and 66.2 ± 3.4%; at 12 months (n = 5), 29.3 ± 1.5, 34.0 ± 1.4%, and 80.2 ± 6.6%. Group mean respective mean HbA1C and glucose levels dropped to 1.1 ± 0.4% and 24.8 ± 6.6 mg/dL (6 months); 2.0 ± 1.1% and 53.8 ± 6.3 mg/dL (12 months). There were 0 device-related AEs, 3 procedure-related serious AEs. No anastomotic bleeding, leakage, stricture, or mortality.
In a multi-center study, side-to-side Magnet System duodeno-ileostomy with SG in adults with class III obesity appeared feasible, safe, and effective for weight loss and T2D resolution in the short term.