Magnets for therapy in the GI tract: a systematic review

Electromagnetic tool for the endoscopic creation of colon anastomoses-development and feasibility assessment of a novel anastomosis compression implant approach

BACKGROUND

Colorectal anastomoses are among the most commonly performed interventions in abdominal surgery, while associated patient trauma is still high. Most recent trends of endoscopic anastomosis devices integrate magnetic components to overcome the challenges of minimally invasive surgery. However, the mutual attraction between magnetic implant halves may increase the risk of inadvertently pinching healthy structures. Thus, we present a novel anastomosis device to improve system controllability and flexibility.

METHODS

A magnetic implant and an applicator with electromagnetic control units were developed. The interaction of magnetic implants with the electromagnets bears particular challenges with respect to the force-related dimensioning. Here, attraction forces must be overcome by the electromagnet actuation to detach the implant, while the attraction force between the implant halves must be sufficient to ensure a stable connection. Thus, respective forces were measured and the detachment process was reproducibly investigated. Patient hazards, associated with resistance-related heating of the coils were investigated.

RESULTS

Anastomosis formation was reproducibly successful for an implant, with an attraction force of 1.53 [Formula: see text], resulting in a compression pressure of [Formula: see text]. The implant was reproducibly detachable from the applicator at the anastomosis site. Coils heated up to a maximum temperature of [Formula: see text]. Furthermore, we were able to establish a neat reconnection of intestinal bowel endings using our implant.

DISCUSSION

As we achieved nearly equal compression forces with our implant as other magnetic anastomosis systems did (Magnamosis™: 1.48 N), we concluded that our approach provides sufficient holding strength to counteract the forces acting immediately postoperatively, which would eventually lead to an undesired slipping of the implant halves during the healing phase. Based on heat transfer investigations, preventive design specifications were derived, revealing that the wall thickness of a polymeric isolation is determined rather by stability considerations, than by heat shielding requirements.

Magnet and wire remodeling for the treatment of candy cane syndrome: first case series of a new approach (with video)

BACKGROUND AND AIMS

Candy cane syndrome (CCS) is an adverse event (AE) from gastrectomy or gastric bypass and end-to-side anastomosis to a jejunal loop. Preferential passage of food to the blind loop induces early satiety, pain, and regurgitation. An endoscopic device that combines 2 magnets and a self-retractable wire was designed to perform progressive septotomy with marsupialization. We evaluated the clinical safety and efficacy of this treatment in CCS.

METHODS

Consecutive patients presenting with symptoms associated with CCS after gastrectomy or Roux-en-Y gastric bypass were treated with the MAGUS (Magnetic Gastrointestinal Universal Septotome) system. Weight, dysphagia, pain scores, 12-item Short Form Survey quality of life physical and mental scores, GERD Health-Related Quality of Life, and Eckardt score were measured at baseline and 1 and 3 months postprocedure. Satisfaction with therapy and AEs were monitored during follow-up.

RESULTS

Fourteen consecutive patients with CCS were enrolled in the study. Thirteen MAGUS systems migrated within 28 days after achieving uneventful complete septotomy. In 1 patient the magnet had to be collected from the right-sided colon after 1 month. Treatment was completed in a single endoscopy session. Dysphagia score (2 [1-3] vs 1 [1-1], P = .02), pain score (7 [6-8] vs 1 [0-1], P = .002), Eckardt score (5 [3-8] vs 1 [0-2], P = .002), GERD Health-Related Quality of Life score (37 [29-45] vs 8 [6-23], P = .002), and quality of life physical and mental scores were all significantly improved at 3 months. No device or procedure-related serious AEs were observed. One patient died during follow-up from evolution of oncologic disease.

CONCLUSIONS

Endoluminal septotomy using a retractable wire and magnet system in CCS is feasible and safe, with rapid improvement of symptoms. (Clinical trial registration number: NCT04480216.).

Endoscopic Magnetic Compression Anastomosis For Small Bowel Bypass in a High Operative Risk Setting

The endoscopic enteroenteral bypass could revolutionize the treatment of small bowel obstruction (SBO) in inoperable patients. We describe the technique of endoscopic delivery of a magnetic compression anastomosis device and the creation of an enteroenteral anastomosis in a patient with recurrent acute on chronic SBOs and prohibitively high operative risk. In this novel procedure, a magnetic compression anastomosis device is delivered on either side of the obstruction using a hybrid endoscopic/fluorographic technique, effectively bypassing the obstruction and relieving symptoms. The anastomosis was endoscopically evaluated at regular intervals postprocedure. By 7 days, healthy villi were visible through the mated magnetic rings. By 10 days, the anastomosis was widely patent. The rings passed through the ileostomy and were evacuated, and the patient's symptoms completely resolved. The anastomosis remained widely patent at 1 year. In summary, this case demonstrates the benefit of magnetic compression anastomosis in a patient with SBO and high operative risk.

Use of magnets in gastrointestinal surgery

BACKGROUND

Laparoscopic and endoscopic surgery has undergone vast progress during the last 2 decades, translating into improved patient outcomes. A prime example of this development is the use of magnetic devices in gastrointestinal surgery. Magnetic devices have been developed and implemented for both laparoscopic and endoscopic surgery, providing alternatives for retraction, anchoring, and compression among other critical surgical steps. The purpose of this review is to explore the use of magnetic devices in gastrointestinal surgery, and describe different magnetic technologies, current applications, and future directions.

METHODS

IRB approval and written consent were not required. In this review of the existing literature, we offer a critical examination at the use of magnets for gastrointestinal surgery currently described. We show the experiences done to date, the benefits in laparoscopic and endoscopic surgery, and additional future implications.

RESULTS

Magnetic devices have been tested in the field of gastrointestinal surgery, both in the contexts of animal and human experimentation. Magnets have been mainly used for retraction, anchoring, mobilization, and anastomosis.

CONCLUSION

Research into the use of magnets in gastrointestinal surgery offers promising results. The integration of these technologies in minimally invasive surgery provides benefits in various procedures. However, more research is needed to continually evaluate their impact and implementation into surgical practice.

Magnetic Anastomosis for Biliojejunostomy: First Prospective Clinical Trial

BACKGROUND

Magnetic compression anastomosis (magnamosis, MCA) has been verified safe and effective by us and others in animal bilioenteric anastomosis (BEA). The objective of the present study was to introduce clinical application of magnetic compression bilioenteric anastomosis (MC-BEA) with a unique device in series of patients.

METHODS

Patients with obstructive jaundice with an indication of BEA were prospectively enrolled from 2012 to 2015. After dissection of bile ducts, the mother ring and drainage tube were placed in the proximal bile duct and the purse-string suture was tightened over the drainage tube. The drainage tube was introduced into the jejunal lumen at the anastomotic site and used to guide the daughter ring to assemble with the mother ring. All the patients were routinely followed up for magnets discharge or any complications associated.

RESULTS

Forty-one patients were included. Thirty-four (82.9%) patients had a malignant primary disease, while seven (17.1%) had benign disease. The median time for MC-BEA was 10.5 min (interquartile range [IQR] 8.3-13.0 min). No perioperative morbidity or mortality associated with MC-BEA was observed. The median time for a patent bilioenteric anastomosis formation was 19.0 days (IQR 14.5-23.0 days), and the magnets were discharged with a median postoperative duration of 35.0 days (IQR 28.0-43.0 days). With a median follow-up of 547.5 days (range 223-1042 days), no patients had biliary fistula, while two (4.9%) developed anastomotic stricture at 4 months and 14 months after surgery, and underwent reoperation for reconstruction of BEA.

CONCLUSIONS

MCA is a safe, effective, and time-saving modality for biliojejunostomy.

Magnetic Compression Anastomosis (Magnamosis) for Functional Undiversion of Ileostomy in Pediatric Patients

INTRODUCTION

Magnamosis forms a compression anastomosis using self-aligning magnetic Harrison rings. The device has been approved by the Food and Drug Administration for first-in-human testing and has been applied in adults for intestinal anastomosis during urologic reconstructions. We now report the first cases of magnamosis to functionally undivert the fecal stream from a previously created loop ileostomy in pediatric patients.

MATERIALS AND METHODS

Case 1: A 4-year-old male underwent a diverting loop ileostomy for malignant bowel obstruction. The obstruction gradually resolved with chemotherapy, and persistently high stomal output and malnutrition prompted undiversion. Case 2: A 16-year-old female with iloecolonic polyposis underwent ileoproctectomy with J pouch and diverting ileostomy. The magnamosis functional undiversion (FUN) technique involves introducing a Harrison ring through each stomal limb under general anesthesia with X-ray guidance. Magnets are each tied with sutures that exit the stoma and are then tied to each other externally. The device is removed when patency is detected.

RESULTS

The introduction procedure took less than 20 minutes and there were no complications. Enteral feeding was initiated 24 and 6 hours postoperatively, and distal passage of stool occurred by the fourth and fifth days, respectively. Magnets were removed 14 and 15 days postoperatively, without evidence of leak.

CONCLUSION

We conclude that the magnamosis undiversion procedure is a safe, minimally invasive way to gradually refunctionalize the excluded distal bowel after previous diverting ostomy.