Sutureless Duodeno-Ileal Anastomosis with Self-Assembling Magnets: Safety and Feasibility of a Novel Metabolic Procedure

Side-to-side magnetic duodeno-ileostomy in adults with severe obesity with or without type 2 diabetes: early outcomes with prior or concurrent sleeve gastrectomy

BACKGROUND

Conventional metabolic/bariatric surgical anastomoses with sutures/staples may cause severe adverse events (AEs).

OBJECTIVES

The study aim was to evaluate the feasibility, safety, and effectiveness of primary and revisional side-to-side duodeno-ileostomy (DI) bipartition using a novel magnetic compression anastomosis device (Magnet Anastomosis System [MS]).

SETTING

Multicenter: private practices and university hospitals.

METHODS

In patients with body mass index ([BMI, kg/m2] ≥35.0 to ≤50.0 with/without type 2 diabetes [T2D] glycosylated hemoglobin [HbA1C > 6.5 %]), two linear MS magnets were delivered endoscopically to the duodenum and ileum with laparoscopic assistance and aligned, initiating magnet fusion and gradual DI (MagDI). The MagDI-after-SG group had undergone prior sleeve gastrectomy (SG); the MagDI + SG group underwent concurrent SG. AEs were graded by Clavien-Dindo Classification (CDC).

RESULTS

Between November 22, 2021 and May 30, 2023, 43 patients (88.0% female, mean age 43.7 ± 1.3 years) underwent the study procedures. The MS met feasibility criteria of magnet device placement, creation of patent anastomoses confirmed radiologically, and magnet passage in 100.0% of patients. There were 64 AEs, most were CDC grade I and II, significantly fewer in the MagDI-after-SG group (P < .001). No device-related AEs including anastomotic leakage, bleeding, obstruction, infection, or death. The MagDI-after-SG group experienced 6-month mean weight loss of 8.0 ± 2.5 kg (P < .01), 17.4 ± 5.0% excess weight loss (EWL). The MagDI + SG group had significantly greater weight loss (34.2 ± 1.6 kg, P < .001), 66.2 ± 3.4% EWL. All patients with T2D improved.

CONCLUSIONS

In early results of a multicenter study, the incisionless, sutureless Magnet System formed patent, complication-free anastomoses in side-to-side DI with prior or concurrent SG.

Influence of different magnetic forces on the effect of colonic anastomosis in rats

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.

AIM

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.

CONCLUSION

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.

Clinical application of magnetic anchor technique in laparoscopic cholecystectomy: the first retrospective study in China

Background and objectives

Magnetic anchor technique (MAT) is frequently used in laparoscopic cholecystectomy. However, there are few reports on its clinical application in China. In this study, we retrospectively analyzed the clinical application of MAT in laparoscopic cholecystectomy in China.

Materials and methods

25 patients (4 males, 21 females) who underwent laparoscopic cholecystectomy assisted by MAT at the First Affiliated Hospital of Xi'an Jiaotong University were enrolled from November 2020 to March 2021. Their records were retrospectively analyzed. The magnetic anchor device was independently designed and developed by the authors and consisted of the anchor magnet and magnetic grasping apparatus. Surgical time, intraoperative blood loss, intraoperative accidents, operator experience, postoperative incision pain score, postoperative complications, and other indicators were evaluated and analyzed.

Results

All patients successfully underwent laparoscopic cholecystectomy, including 3 cases of MAT-assisted transumbilical single-port LC, 16 cases of MAT-assisted 2-port LC and 6 cases of conventional 3-port LC. The median operation time was 50 min (range 30-95 min); intraoperative bleeding was less than 30 ml. The median score of surgical incision on day 1 and 3 after the operation was 3 (range 1-4) and 1 (range 1-3), respectively. All patients had no intraoperative bile duct injury, vascular injury, postoperative bleeding, bile leakage, biliary stricture and other complications. No adverse events (such as injury to adjacent organs or failure of the magnetic anchor device) occurred either during or after the operation.

Conclusions

The MAT-assisted laparoscopic cholecystectomy appears to be safe, feasible and effective and exhibits unique assistance in transumbilical single-port laparoscopic cholecystectomy.

Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled magnetic anastomosis rings (DSAMARs) in a pig model

BACKGROUND

To investigate the feasibility of a deformable self-assembled magnetic anastomosis ring (DSAMAR), designed and developed by us, for endoscopic gastrointestinal bypass anastomosis.

METHODS

Ten experimental pigs were used as model animals. The DSAMAR comprises 10 trapezoidal magnetic units, arranged in a straight line under the constraint of a guide wire. When the desired anastomosis site is reached under the guidance of an endoscope, the catheter pushes the magnetic unit along the guide wire. The linear DSAMAR can be assembled into a circular DSAMAR. Two DSAMARs were inserted, one at the end of the duodenum and the other into the stomach successively. They attracted each other and compressed the wall of the stomach and duodenum to establish gastrointestinal bypass anastomosis. The experimental pigs were euthanized 4 weeks after the operation, and the gastrointestinal bypass anastomosis specimens were obtained. The anastomosis formation was evaluated by the naked eye and histology.

RESULTS

Gastrointestinal bypass anastomosis with DSAMARs was successfully performed. The average operation time under an endoscope was 70.30 ± 19.05 min (range: 43-95 min). The DSAMARs were discharged through the anus 10-17 days after surgery. There were no complications such as gastrointestinal bleeding, perforation, anastomotic fistula, and gastrointestinal obstruction during and after the operation. Gastroscopy and gross specimen of the anastomosis showed a well-formed magnetic anastomosis. Histological observation showed good continuity of the serous membrane and the mucosa of magnetic anastomosis.

CONCLUSION

The DSAMAR is a safe and feasible device for fashioning gastrointestinal bypass anastomosis in this animal model.

A Novel Deformable Self-Assembled Magnetic Anastomosis Ring (DSAMAR) for Esophageal Stenosis Recanalization without Temporary Gastrostomy in Beagle Dogs

BACKGROUND

To assess the feasibility of a deformable self-assembled magnetic anastomosis ring (DSAMAR) in the treatment of esophageal stenosis in beagle dogs via transoral access without temporary gastrostomy.

METHODS

Experimental esophageal stenosis was created in 10 beagle dogs by partial cervical esophageal ligation. The DSAMAR was inserted into the distal esophagus via the narrow section of the esophagus using a gastroscope. A circular DSAMAR was placed in the proximal esophagus. The magnetic rings on both sides of the experimental stenosis automatically attracted each other. We then recorded the operation time, postoperative complications, anastomotic formation time, and magnetic ring discharge time. The dogs were euthanized 4 weeks postoperatively; subsequently, we obtained the esophageal anastomotic specimens and observed the anastomotic formation via the naked eye and by light microscopy.

RESULTS

Our esophageal stenosis model produced reproducible stenoses in all dogs, which was confirmed via endoscopy and esophagography. DSAMAR was successfully implanted in all experimental animals under endoscopic and X-ray monitoring, and all linear DSAMARs were successfully transformed into rings. The magnets at both ends of the esophageal stenosis were automatically attracted. All animals survived until euthanasia. No complications, including esophageal perforation, bleeding, and gastrointestinal obstruction, were noted during the perioperative period. The mean operation time of endoscopic magnetic anastomosis was 15.6 ± 2.41 (range, 12-19) min. The mean esophageal anastomotic formation time was 8.8 ± 1.03 (range, 7-10) days, and the mean expulsion time of DSAMAR was 13.94 ± 2.88 (range, 10-19) days. Gastroscopy and esophagography were performed at 4 weeks postoperatively; the esophageal patency was good. Macroscopic observation of the esophageal anastomotic specimens revealed that the esophageal mucosal layer of the anastomosis had good continuity and the anastomosis was smooth.

CONCLUSION

DSAMAR is a feasible option for magnetic recanalization of esophageal stricture via transoral access without temporary gastrostomy.

First-in-Human Side-to-Side Magnetic Compression Duodeno-ileostomy with the Magnet Anastomosis System

PURPOSES

Classical gastrointestinal anastomoses are formed with sutures and/or metal staples, resulting in significant bleeding and leak rates. This study evaluated the feasibility and safety of the novel magnet anastomosis system (MS) to create a side-to-side duodeno-ileal (DI) diversion for weight loss and type 2 diabetes (T2D) resolution.

MATERIALS AND METHODS

Patients with severe obesity (body mass index (BMI) ≥ 35 kg/m2 with/without T2D (HbA1C ≥ 6.5%)) underwent the study procedure, a side-to-side MS DI diversion, with a standard sleeve gastrectomy (SG). A linear magnet was delivered by flexible endoscopy to a point 250 cm proximal to the ileocecal valve; a second magnet was positioned in the first part of the duodenum; the bowel segments containing magnets were apposed, initiating gradual anastomosis formation. Laparoscopic assistance was used to obtain bowel measurements, obviate tissue interposition, and close mesenteric defects.

RESULTS

Between November 22 and 26, 2021, 5 female patients (mean weight 117.6 ± 7.1 kg, BMI (kg/m2) 44.4 ± 2.2) underwent side-to-side MS DI + SG. All magnets were successfully placed, expelled without re-intervention, and formed patent durable anastomoses. Total weight loss at 12 months was 34.0 ± 1.4% (SEM); excess weight loss, 80.2 ± 6.6%; and BMI reduction, 15.1. Mean HbA1C (%) dropped from 6.8 ± 0.8 to 4.8 ± 0.2; and glucose (mg/dL), from 134.3 ± 17.9 to 87.3 ± 6.3 (mean reduction, 47.0 mg/dL). There was no anastomotic bleeding, leakage, obstruction, or infection and no mortality.

CONCLUSIONS

Creation of a side-to-side magnetic compression anastomosis to achieve duodeno-ileostomy diversion in adults with severe obesity was feasible and safe, achieved excellent weight loss, and resolved type 2 diabetes at 1-year follow-up.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT05322122.

Primary animal experiment to test the feasibility of a novel Y-Z magnetic hepatic portal blocking band

BACKGROUND

Hepatic portal blood flow occlusion is a common technique for reducing hepatic hemorrhage during hepatectomy. We designed a novel Y-Z magnetic hepatic portal blocking band (Y-Z MHPBB) based on the principle of magnetic compression technique.

AIM

To introduce the Y-Z MHPBB device and verify the feasibility of this device for hepatic portal blood flow occlusion in dogs.

METHODS

Ten beagles were randomly divided into the experimental group and control group. The operation time, intraoperative blood loss, the number of portal blood flow occlusions, the total time spent on adjusting the blocking band, and the average time spent on adjusting the blocking band were recorded. The surgeons evaluated the feasibility and flexibility of the two portal occlusion devices.

RESULTS

Laparoscopic hepatectomy was successfully performed in both the experimental group and control group. There was no statistical difference between the two groups in the operation time, intraoperative blood loss, and the number of hepatic portal blood flow occlusions. With respect to the total time spent on adjusting the blocking band and the average time spent on adjusting the blocking band, the experimental group showed significantly better outcomes than the control group, with a statistical difference (P < 0.05). The operators found that the Y-Z MHPBB was superior to the modified T-tube in terms of operational flexibility.

CONCLUSION

The Y-Z MHPBB seems to be an ingenious design, accurate blood flow occlusion effect, and good flexibility; and it can be used for hepatic portal blood flow occlusion during laparoscopic hepatectomy.

Side-to-side magnet anastomosis system duodeno-ileostomy with sleeve gastrectomy: early multi-center results

INTRODUCTION

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.

METHODS

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).

RESULTS

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 HbA1_C 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.

CONCLUSION

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.

Side-to-side duodeno-ileal magnetic compression anastomosis: design and feasibility of a novel device in a porcine model

BACKGROUND

Minimally invasive metabolic/bariatric surgery (MBS) may be further advanced by magnetic compression anastomosis (MCA) technology. The study aimed to develop a magnet sized to create a patent duodeno-ileostomy (DI) and verify its effectiveness in a porcine model.

METHODS

Developmental study phase: magnets with 4 different flange-offset dimensions were tested to identify a design that would successfully form a compression anastomosis. Verification phase: evaluation of the selected design's efficacy. In each 6-week phase (4 pigs/phase), one magnet was inserted laparoscopically in the jejunum, one placed gastroscopically in the duodenum. Magnets were aligned, gradually fused, formed an anastomosis, and then detached and were expelled. At necropsy, MCA sites and sutured enterotomy sites were collected and compared.

RESULTS

Developmental phase: the linear BC42 magnet with a 2.3-mm flange offset design was selected. Verification phase: in 4 swine magnets were mated at the target location, confirmed radiographically. Mean time to magnet detachment 16.0 days (12-22), to expulsion 24.5 days (17-33). MCA was achieved in all animals at time of sacrifice. Animals gained a mean 9.5 kg (3.9-11.8). Specimens revealed patent anastomoses of ≥ 20 mm with smooth mucosa and minimal inflammation and fibrosis compared to sutured enterotomies. One pig underwent corrective surgery for a mesenteric hernia without sequelae.

CONCLUSION

In a large-animal model, gross and histopathologic examination confirmed that the linear MCA device created a patent, well-vascularized, duodeno-ileal anastomosis. The novel MCA device may be appropriate for use in human MBS procedures.

Comparative early histologic healing quality of magnetic versus stapled small bowel anastomosis

BACKGROUND

Successful anastomotic healing is critical to preventing complications after intestinal surgery. We aimed to compare the early healing of end-to-end small bowel anastomosis by self-forming magnets with surgical stapling in a porcine model.

METHOD

Six Yorkshire pigs underwent 2 simultaneous small bowel anastomoses using a circular stapler and self-forming magnet technique. The primary outcome was healing quality, measured by 4 histologic features: inflammatory cell infiltration, collagen formation, grade of inflammation, and bacterial infiltration at the anastomosis. The samples were evaluated at days 1, 3, and 7. Gross evaluation of anastomotic integrity was a secondary outcome.

RESULTS

The self-forming magnet group displayed significant differences at each time point. On day 1, the stapled group displayed dense inflammatory cell infiltration and extensively ulcerated intestinal layers with significant edema. The self-forming magnet group showed less inflammatory infiltrate, and all intestinal layers remained compressed in direct apposition. By day 3, the self-forming magnet group already exhibited neovascularization with scant bacterial colonies. By contrast, stapled anastomoses had large areas of inflammation separating collagen fibers with prevalent bacterial infiltrations. On day 7, self-forming magnet anastomoses were characterized by robust neovascularization, maturing granulation tissue, and mucosal re-epithelization without significant inflammation. Meanwhile, stapled samples had persisting dense inflammation, tissue cavities with hemorrhage, and immature fibrous tissue. Grossly, the self-forming magnet created a patent lumen without defect, whereas stapled anastomoses demonstrated focal areas of serosal separation.

CONCLUSION

Bowel anastomosis by self-forming magnets is associated with superior early histologic healing metrics, including early seal generation through mechanical compression, decreased inflammation, early neovascularization, lower bacterial infiltration, and faster re-epithelization.

The Evolving Use of Magnets in Surgery: Biomedical Considerations and a Review of Their Current Applications

The novel use of magnetic force to optimize modern surgical techniques originated in the 1970s. Since then, magnets have been utilized as an adjunct or alternative to a wide array of existing surgical procedures, ranging from gastrointestinal to vascular surgery. As the use of magnets in surgery continues to grow, the body of knowledge on magnetic surgical devices from preclinical development to clinical implementation has expanded significantly; however, the current magnetic surgical devices can be organized based on their core function: serving as a guidance system, creating a new connection, recreating a physiologic function, or utilization of an internal–external paired magnet system. The purpose of this article is to discuss the biomedical considerations during magnetic device development and review the current surgical applications of magnetic devices.

Creation of gastroenteric anastomosis through natural orifice in rats by magnetic compression technique

BACKGROUND

Being one of the core techniques of magnetic surgery, magnetic compression technique (MCT) has been used for digestive tract anastomosis reconstruction in experimental studies. This study verified the feasibility of gastroenteric anastomosis through natural orifice using MCT in rats.

METHODS

The parent and daughter magnets were designed and manufactured for oral and anal insertion in 20 Sprague-Dawley rats. After anesthesia, the parent magnet was inserted into the colon spleen area through the anus, and the daughter magnet was inserted into the stomach through the mouth. Then the two magnets were positioned to attract each other and bind together. The position of the two magnets was monitored using X-ray. The time required for the formation of the anastomosis and expulsion of the magnets were recorded. 2 weeks later, the animal was sacrificed and the anastomotic specimen was obtained which was observed under naked eye and microscope.

RESULTS

The gastroenteric anastomosis was successfully performed via natural orifices in 18 out of 20 rats. The mean time to construct the anastomosis was 3.78 ± 0.88 min. X-ray examination showed that the magnets were in the appropriate position in 17 rats. The magnets were excreted in 9.47 ± 1.62 days after surgery. The gross and microscopic examination of the specimen showed that the anastomoses were patent and the mucosa at the anastomotic was smooth. The mean bursting pressure of the anastomosis was 136.94 ± 6.79 mmHg.

CONCLUSION

It is feasible to perform gastroenteric anastomosis through natural orifices by MCT.

A novel magnetic compression technique for cystostomy in rabbits

Magnetic compression technique (MCT) is a popular new anastomosis method. In this paper, we aimed to explore the feasibility of use of MCT for performing cystotomy in rabbits. The parent magnets and daughter magnets for rabbit cystostomy were designed and manufactured according to the anatomical characteristics of rabbit lower urinary tract. Twelve female New Zealand rabbits were used as animal models. After anesthesia, a daughter magnet was inserted into the bladder through the urethra, and the parent magnet was placed on the body surface projection of the bladder over the abdominal wall. The two magnets automatically attract each other. Postoperatively, the state of magnets was monitored daily, and the time when the magnets fell off was recorded. Cystostomy with MCT was successfully performed in all twelve rabbits. The mean operation time was 4.46 ± 0.75 min. The magnets fell off from the abdominal wall after a mean duration of 10.08 ± 1.62 days, resulting in the formation of bladder fistula. Macroscopic and microscopic examination showed that the fistula was well formed and unobstructed. The junction between bladder and abdominal wall was tight and smooth. We provide preliminary experimental evidence of the safety and feasibility of cystostomy based on MCT.