Repair of esophageal atresia with proximal fistula using endoscopic magnetic compression anastomosis (magnamosis) after staged lengthening

Magnets in Paediatric Surgery

Magnetism, recognized in ancient Greece and China, is a fundamental physical force influencing numerous domains, including medicine and surgery. Historically, the medical use of magnets dates back over two millennia. As proof, the ancient Sanskrit medical textbook Sushruta Samhita describes the removal of a metallic arrow lodged in the flesh with a magnet. Modern uses span from diagnostic to therapeutic applications, including in paediatric surgery. High-field magnetism, utilized in Magnetic Resonance Imaging and Transcranial Magnetic Stimulation (TMS), shows promise for various medical conditions, including depression and neurodegenerative diseases. Despite controversy surrounding low-field magnetism, its potential remains a topic of interest. One of the applications in paediatric surgery that has been evaluated in a randomized controlled trial is magnetic acupuncture for supplementary treatment of postoperative pain. As most paediatric surgeons are well aware, the use of magnets also poses risks, particularly in children, where ingested magnets can cause severe gastrointestinal complications. Regulations have tightened in response to increasing cases of magnet ingestion-related injuries but more needs to be done to avoid injury. Currently, magnets play crucial roles in a variety of medical applications, including magnetic cell sorting and therapeutic devices. Notably, magnetic compression anastomosis, which uses magnets to facilitate luminal tissue joining, have seen significant advancements. Innovations include devices for oesophageal atresia repair, with recent studies showing promising results in animal models and early clinical trials. Future research should focus on optimizing magnetic devices, expanding their applications, and ensuring safety. The continued exploration of magnetism's effects on living tissues and the development of new magnetic technologies could revolutionize medical and surgical practices, particularly in paediatric care.

Primary repair of esophageal atresia Gross type C via thoracoscopic magnetic compression anastomosis: Is it the best option?

Magnetic compression anastomosis is a promising treatment option for patients with complex esophageal atresia; but, at the present time, should not be the first therapeutic option in those cases where the surgeon can perform a primary anastomosis of the two ends of the esophagus with acceptable tension.

Use of magnets in pediatric surgery

Since the 1970s, magnets have been progressively harnessed for use in minimally invasive treatment of pediatric surgical disease. In particular, multiple magnetic devices have been developed for treating esophageal atresia, pectus excavatum and scoliosis. These devices, which can be placed via small incisions or under endoscopic or fluoroscopic guidance, provide the added benefit of sparing patients multiple large, invasive procedures, and allowing for gradual correction of congenital anomalies over days to months, depending on the disease. In the following text, we detail the current landscape of magnetic devices used by pediatric surgeons, illustrate their use through clinical cases, and review the available body of literature with respect their outcomes and complications.

Role of Magnetic Compression Anastomosis in Long-Gap Esophageal Atresia: A Systematic Review

Background: Magnetic compression anastomosis (MCA) is an alternative technique for patients with long-gap esophageal atresia (EA). It allows for preservation of the native esophagus. We aimed to systematically summarize the current literature on MCA in EA. Methods: Studies where neonates with EA were treated with MCA devices were included, while studies on esophageal stenosis were excluded. All clinical studies, including comparative studies, case series, and case reports, were eligible for inclusion. Methodological quality assessment was performed using a validated tool. Results: Twelve studies with a total of 42 patients were included in this review. There was a wide variation among these studies with regard to the time of initiation of MCA (1 day to 7 months), procedure time (13-320 minutes), and magnet characteristics (strength, size, and shape of the magnets used). The time to achieve anastomosis ranged from 1 to 12 days. Stricture at the anastomotic site was reported in almost all the patients, which required multiple endoscopic dilatations (median no. of dilatations/patient = 9.8). Stent placement for refractory stricture was required in 9 (21%) patients, and surgery for stricture was required in 6 (14%) patients. Long-term outcomes included esophageal dysmotility (n = 3) and recurrent pulmonary infections (n = 3) were reported in only four studies. Conclusion: As per the findings of this review, neonates with long-gap EA undergoing MCA would invariably require multiple sittings of endoscopic dilatations (median no. of dilatations/patient = 9.8). Also, there is a wide variation among the included studies in terms of the procedure of MCA. Future studies with a standardized procedure for achieving MCA are needed to determine additional outcomes in this fragile patient population.

Liver transplantation using magnetic anastomosis in pigs

Magnetic anastomosis substantially shortens the duration of vascular anastomosis. We aimed to apply magnetic anastomosis technology (MAT) to donor liver implantations in pig orthotopic liver transplantation (OLT). Twenty healthy adult pigs were randomly divided into donors and recipients, and major vascular anastomosis was performed using MAT during OLT. Recipient liver and kidney function was measured pre-surgery and 12, 24 and 72 h post-surgery. Vascular anastomoses examinations were performed using ultrasound or angiography weekly post-surgery, and pathological examinations of vascular anastomoses were performed during autopsy after animal euthanasia. All recipients survived 24 h after surgery, which is considered as successful transplantation. Anhepatic duration was only 13 min, and no anastomotic obstruction or stenosis, magnetic displacement and anastomotic angulation, or distortion was found upon postoperative examinations of major liver vasculature. Aspartate aminotransferase, alanine aminotransferase, and total bilirubin serum levels increased considerably postoperatively. The follow-up period for this study was 1 year, and the median survival time of all recipients was 115 d (interquartile range = 11-180 d). The main causes of death were liver failure, immune rejection, infection, and arterial anastomotic bleeding. Moreover, vascular anastomoses healed well with a survival time of more than two weeks. We developed a novel magnetic device to create a fast and safe technique to perform major vascular anastomoses in pig liver transplantations. Additionally, the liver graft implantation using MAT considerably shortened the recipient warm ischemia time, which will reduce the extent of ischemia-reperfusion injury. We conclude that MAT is an effective method for donor liver fast implantation in OLT in pigs.

Magnetic Compression Anastomosis-Past Experience and Current Proposals for Further Development in Pediatric Minimally Invasive Surgery

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.

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.

Magnamosis for long gap esophageal atresia: Minimally invasive "fatal attraction"

BACKGROUND

Aim of study is to report our preliminary experience with magnetic anastomosis (magnamosis) treating long-gap esophageal atresia (LGEA), the most challenging condition of esophageal atresia continuum. Magnamosis has been reported in 20 patients worldwide as an innovative and marginally invasive option.

METHODS

Prospective evaluation of all LGEA patients treated with magnamosis was performed (study registration number: 2535/2021). Main outcomes considered were demographic and surgical features, postoperative complications and feeding within 6-month of follow-up.

RESULTS

Between June 2020 and January 2021, 5 LGEA patients (Type A, Gross classification) were treated. Median preoperative gap was 5 vertebral bodies. Magnetic bullets were placed at an average age of 81 days of life, leading to successful magnamosis in all cases: 4 infants had primary magnetic repair (one after thoracoscopic mobilization of the pouches), 1 patient had a delayed magnamosis after Foker's procedure. Esophageal anastomosis was achieved after an average of 8 days. No anastomotic leak was found. All patients developed anastomotic stenosis at 6-month follow-up, requiring a mean of 6 dilations each. Full oral feeding was achieved in 3 patients, while 2 were still on oral-gastrostomy feeding. One patient experienced small esophageal perforation after dilation (3 months after magnamosis), distal to the anastomotic stricture and subsequently developed oral aversion.

CONCLUSIONS

Our preliminary results suggest magnamosis a safe and effective minimally invasive option in patients with LGEA. Absence of postoperative esophageal leaks may represent a major advantage of magnamosis over conventional surgery, although possible high rate of esophageal stenosis should be further evaluated.

LEVELS OF EVIDENCE

IV (Case series with no comparison group).

The novel application of an emerging device for salvage of primary repair in high-risk complex esophageal atresia

INTRODUCTION

Preservation of native esophagus is a tenet of esophageal atresia (EA) repair. However, techniques for delayed primary anastomosis are severely limited for surgically and medically complex patients at high-risk for operative repair. We report our initial experience with the novel application of the Connect-EA, an esophageal magnetic compression anastomosis device, for salvage of primary repair in 2 high-risk complex EA patients. Compassionate use was approved by the FDA and treating institutions.

OPERATIVE TECHNIQUE

Two approaches using the Connect-EA are described - a totally endoscopic approach and a novel hybrid operative approach. To our knowledge, this is the first successful use of a hybrid operative approach with an esophageal magnetic compression device.

OUTCOMES

Salvage of delayed primary anastomosis was successful in both patients. The totally endoscopic approach significantly reduced operative time and avoided repeat high-risk operation. The hybrid operative approach salvaged delayed primary anastomosis and avoided cervical esophagostomy.

CONCLUSION

The Connect-EA is a novel intervention to achieve delayed primary esophageal repair in complex EA patients with high-risk tissue characteristics and multi-system comorbidities that limit operative repair. We propose a clinical algorithm for use of the totally endoscopic approach and hybrid operative approach for use of the Connect-EA in high-risk complex EA patients.

Esophageal magnetic compression anastomosis in dogs

BACKGROUND

Magnetic compression anastomosis (MCA) is a novel suture-free reconstruction of the digestive tract. It has been used in gastrointestinal anastomosis, jejunal anastomosis, cholangioenteric anastomosis and so on. The traditional operative outcomes of congenital esophageal atresia and benign esophageal stricture are poor, and there are too many complications postoperatively.

AIM

To test MCA technology to reconstruct the esophagus in dogs, prior to studying the feasibility and safety of MCA in humans.

METHODS

Thirty-six dogs were randomized into either the study or control group (n = 18 per group). The dogs in the study group were subjected to end-to-end esophageal anastomosis with the magnetic compression device, while those in the control group underwent hand-sewn anastomosis with 4-0 absorbable multifilament Vicryl. We used interrupted single-layer inverting sutures. The anastomosis time, gross appearance, weight and pathology of the anastomosis were evaluated at one month, three months and six months postoperatively.

RESULTS

The anastomosis time of the MCA group was shorter than that of the hand-sewn group (7.5 ± 1.0 min vs 12.5 ± 1.8 min, P < 0.01). In the MCA group, X-ray examination was performed every day to locate the magnetic device in the esophagus before the magnetic device fell off from the esophagus. In the hand-sewn group, dogs did not undergo X-ray examination. One month after the surgeries, the mean weight of the dogs in the hand-sewn group had decreased more than that of the dogs in the MCA group (11.63 ± 0.71 kg vs 12.73 ± 0.80 kg, P < 0.05). At 3 mo and 6 mo after the operation, the dogs' weights were similar between the two groups (13.75 ± 0.84 kg vs 14.03 ± 0.82 kg, 14.93 ± 0.80 kg vs 15.44 ± 0.47 kg). The number of inflammatory cells in MCA group was lower than that in hand-sewn group on 1 mo after operation.

CONCLUSION

MCA is an effective and safe method for esophageal reconstruction. The anastomosis time of the MCA group was less than that of the hand-sewn group. This study shows that MCA technology may be applied to human esophageal reconstruction, provided these favorable results are confirmed by more publications.

Esophageal Magnetic Compression Anastomosis in Esophageal Atresia Repair: A PRISMA-Compliant Systematic Review and Comparison with a Novel Approach

The use of magnet compression to endoscopically create an esophageal anastomosis is an intriguing approach to esophageal atresia repair, but published cases with an existing available device have demonstrated mixed success. One major shortcoming has been the formation of subsequent severe, recalcitrant strictures after primary repair. To address the limitations of the existing device, we recently introduced and reported success with specially designed bi-radial magnets that exhibit a novel geometry and unique tissue compression profile. The aim of this study is to compare the outcomes using our novel device (novel group, NG) with those of previous reports which utilized the historical device (historic group, HG) in a PRISMA-compliant systematic review. Seven studies were eligible for further analysis. Additionally, one of our previously unreported cases was included in the analysis. Esophageal pouch approximation prior to primary repair was performed more frequently in the NG than in the HG (100% NG vs. 21% HG; p = 0.003). There was no difference in the overall postoperative appearance of postoperative stricture (95% HG vs. 100% NG; p = 0.64). The number of postoperative dilatations trended lower in the NG (mean 4.25 NG vs. 9.5 HG; p = 0.051). In summary, magnetic compression anastomosis adds a new promising treatment option for patients with complex esophageal atresia. Prior approximation of pouches and a novel magnet design have the potential to lower the rate of stricture formation.

Lumen reconstruction with magnetic compression anastomosis technique in a patient with complete esophageal stricture

Background: Complete esophageal obstruction (CEO) is a rare condition of which treatment options are challenging. Surgery is the main treatment with high morbidity and mortality rates. Magnetic compression anastomosis (MCA) is a novel technique developed to restore lumen patency in gastrointestinal and biliary tracts. However, MCA experience is limited in respect of esophageal strictures. Case Report: We present a 26-year-old patient having CEO. Magnets are inserted endoscopically to both sides of the obstructed area via oral and retrograde (through the gastrostomy tract) route. On day 8, magnets stuck together and were removed endoscopically through the oral route. Subsequently, sessions of balloon dilatations and triamcinolone injection were performed. The patient’s complaint of aphagia resolved after the treatment process. Conclusion: In conclusion, MCA is an alternative technique that can be used to restore lumen patency in esophageal strictures and also avoids complications of surgical interventions.

An experimental study on long term outcomes after magnetic esophageal compression anastomosis in piglets

BACKGROUND/PURPOSE

Previous studies have shown that a patent, watertight esophageal anastomosis can be accomplished safely using specially-shaped magnets in piglets. However, it is unclear whether such a magnetic esophageal compression anastomosis (MECA) remains patent in the long-term. The purpose of this study was to evaluate the long-term outcome of MECA in an experimental pig model over an observation period of 2 months.

METHODS

Ten piglets underwent creation of an MECA with custom-made 8 mm magnets and a U-shaped esophageal bypass loop to allow peroral nutrition at eight weeks of life. Two weeks later, the bypass loop was closed surgically, requiring the pigs to swallow via the newly created magnetic compression anastomosis. The pigs were fed soft chow for 2 months. They were monitored for weight gain and signs of dysphagia. At the endpoint of two months, esophagoscopy and contrast esophagography was performed. After removal of the esophagus, the tissues were macroscopiocally and histologically assessed.

RESULTS

Six piglets survived until the endpoint. In two pigs, closure of the bypass loop failed, these demonstrated mean weight gain of 792 gs/day [95% Confidence interval 575 to 1009 gs/day]. Weight gain in four pigs that exclusively fed via the magnetic anastomosis averaged 577 gs/day [95% confidence interval 434 to 719 gs/day (p = 0.18)]. There were no signs of dysphagia. All magnets passed with the stool within 16 days. After 2 months, a well-formed magnetic compression anastomosis was visible and easily negotiated with a 6.5 mm endoscope. Esophogram and macroscopic findings confirmed patentency of the esophageal anastomoses. Histopathology showed a circular anastomosis lined with contiguous epithelium.

CONCLUSION

MECA creates a long-term functional and patent anastomosis in pigs. This concept may facilitate minimally-invasive esophageal atresia repair by obviating a technically challenging and time-consuming hand-sewn anastomosis.

Advances and Trends in Pediatric Minimally Invasive Surgery

As many meta-analyses comparing pediatric minimally invasive to open surgery can be found in the literature, the aim of this review is to summarize the current state of minimally invasive pediatric surgery and specifically focus on the trends and developments which we expect in the upcoming years. Print and electronic databases were systematically searched for specific keywords, and cross-link searches with references found in the literature were added. Full-text articles were obtained, and eligibility criteria were applied independently. Pediatric minimally invasive surgery is a wide field, ranging from minimally invasive fetal surgery over microlaparoscopy in newborns to robotic surgery in adolescents. New techniques and devices, like natural orifice transluminal endoscopic surgery (NOTES), single-incision and endoscopic surgery, as well as the artificial uterus as a backup for surgery in preterm fetuses, all contribute to the development of less invasive procedures for children. In spite of all promising technical developments which will definitely change the way pediatric surgeons will perform minimally invasive procedures in the upcoming years, one must bear in mind that only hard data of prospective randomized controlled and double-blind trials can validate whether these techniques and devices really improve the surgical outcome of our patients.

New Technique for Magnetic Compression Anastomosis Without Incision for Gastrointestinal Obstruction

BACKGROUND

Magnetic compression anastomosis (MCA) is a novel technique of anastomosis similar to that with surgery, but in a minimally invasive manner. Few reports are available on the utility and feasibility of MCA for gastrointestinal anastomosis without requiring general anesthesia in humans, owing to the difficulty of delivering magnets. We evaluated the safety, efficacy, and feasibility of MCA in gastrointestinal obstruction without requiring general anesthesia.

STUDY DESIGN

In this retrospective single-center study, patients who underwent MCA from January 2013 to October 2019 were included. Adult patients with gastrointestinal obstruction or stenosis, irrespective of the underlying disease, with severe comorbidities, complicated abdominal surgical history, or postoperative complications, and who were unable to tolerate surgery, were eligible for inclusion. Two magnets were delivered by a combination of endoscopic and fluoroscopic procedures and placed in the lumen of the organ to be anastomosed. The main outcome was the technical success of MCA.

RESULTS

Fourteen patients underwent MCA, and the technical success of MCA was achieved in 100% of the cases. The mean procedural time, duration for anastomosis formation, and postoperative hospital stay were 44 minutes, 13 days, and 36 days, respectively. Two patients underwent anastomotic restenosis, and 1 patient had an anastomotic perforation due to balloon dilatation to prevent restenosis. The mean follow-up period was 34 months.

CONCLUSIONS

MCA without general anesthesia for gastrointestinal anastomosis is safe, useful, and feasible. MCA can be a valuable alternative to surgery in gastrointestinal obstruction.

Magnetic compression for anastomosis in treating an infant born with long-gap oesophageal atresia: A case report

RATIONALE

Neonatal long-gap esophageal atresia (LGEA) with tracheoesophageal fistula (TEF) is an uncommon but serious congenital malformation of the esophagus in newborns, and it remains challenging for pediatric surgeons. Magnetic compress has been shown to be effective for the treatment of LGEA in children and adults. However, the implementation of this unique technique for neonatal LGEA has not been evaluated.

PATIENT CONCERNS

A female infant was born at 37 weeks of gestation. Prenatal ultrasound imaging revealed signs of esophageal atresia, including the absence of the gastric bubble and polyhydramnios.

DIAGNOSES

A diagnosis of LGEA with TEF was confirmed at birth by contrast X-ray.

INTERVENTIONS

She was treated with magnetic compression anastomosis (MCA) following an esophago-esophagostomy. Two magnetic rings were customized, and the MCA was conducted during the same stage surgery of ligating the TEF. Under the magnetic force, the 2 magnet rings pulled along the gastric tube to achieve anastomosis. The postoperative permanent suction of these 2 pouches was instituted, and spontaneous growth was awaited. Magnet removal was performed at 36 days, and enteral nutrition was continued via a gastric tube for 4 weeks at post-operation.

OUTCOMES

The upper gastrointestinal contrast confirmed the anastomotic patency perfectly after 3 months. The patient was followed up for 18 months, and exhibited durable esophageal patency without dysphagia.

LESSONS

These results suggest that MCA is feasible and effective for treating LGEA in infants.

Constant magnetic field in treating congenital esophageal and anorectal malformation: a review

Background

Congenital esophageal and anorectal malformation are common in neonates. Refractory esophageal anastomotic stricture and abnormal defecation after surgical correction in infants are challenging surgical problems. Magnetic compression anastomosis (MCA) using mated magnets with their interposed compressed tissue may result in serosa-to-serosa apposition.

Data sources

A literature search was performed to establish an algorithm for these accidents by the authors to identify relevant articles published from 1977 to 2019 in Google, Medline, ISI Web of Knowledge Ovid, CNKI and library document delivery, using search terms “magnetics”, “esophageal malformation”, “anorectal” and “perforation”. A total of 24 literatures were collected.

Results

Magnamosis is technically feasible for alimentary tract anastomoses in pediatric patients. The magnets are most commonly made of neodymium–iron–boron and samarium–cobalt alloys, which have been employed to create solid anastomosis for long-gap esophageal atresia and refractory esophageal stricture without thoracotomy in children in recent years. Furthermore, magnamosis can be used for the functional undiversion of ileostomy. In anorectal malformations with favorable anatomy, this procedure may avoid an operative repair such as posterior sagittal reconstruction.

Conclusion

Translumenal anastomosis of digestive tract using the MCA is a reliable, minimally invasive and feasible method to treat congenital esophageal and anorectal malformation.

Magnamosis for esophageal atresia is associated with anastomotic strictures requiring an increased number of dilatations

BACKGROUND/PURPOSE

Magnamosis is a novel technique which utilizes high power magnets to anastomose the esophageal ends in children with esophageal atresia (EA) with or without a tracheoesophageal fistula (TEF), theoretically avoiding the need for thoracotomy. The objective of this study was to compare anastomotic stricture formation requiring dilatation after magnamosis versus after conventional anastomosis.

METHODS

Our center treated the first 3 cases of EA ± TEF with magnamosis in Canada. One was unsuccessful and excluded from our study. The number of postintervention dilatations was compared to controls from our database, which includes all children with EA ± TEF treated between 1991 and 2015. The controls had EA ± TEF treated with pouch-to-end anastomosis or colonic interposition (n = 65). Mann-Whitney U tests were used with p < 0.05 being significant.

RESULTS

The 2 magnamosis cases had a mean of 13.5 dilatations, compared to 2.6 for the controls. Those managed with pouch-to-end anastomosis or colonic interposition had a mean of 2.3 and 2.7 dilatations, respectively. We found that the cases required more dilatations than controls (p = 0.022) and pouch-to-end anastomosis (p = 0.021), but not than colonic interposition (p = 0.106).

CONCLUSION

Our results indicate that magnamosis is associated with more postintervention dilatations than conventional anastomotic techniques, suggesting that magnamosis results in more frequent and/or more resilient anastomotic strictures.

LEVEL OF EVIDENCE

3.

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.

An experimental study on magnetic esophageal compression anastomosis in piglets

INTRODUCTION

Fashioning a patent, watertight anastomosis in patients with esophageal atresia is a challenging task in pediatric surgery, particularly when performed under tension. A reproducible suture-less alternative would decrease operative time. We evaluated magnetic esophageal compression anastomoses in a novel bypass-loop swine model.

METHODS

Eight-week-old piglets underwent thoracotomy to mobilize the esophagus at the carina to create a U-shaped loop. Custom-made 8 mm diameter Neodymium Magnets were inserted into the esophagus proximal and distal to the loop, then mated side-to-side at the future anastomosis site. Pigs were observed for 8 (n = 4), 10 (n = 6), and 12 (n = 2) days and then sacrificed. The magnetic compression anastomosis was evaluated macroscopically, by radiography, burst pressure testing, and histology.

RESULTS

All 12 pigs survived until the endpoint. Separation of the magnets occurred at a median of 9 days. Contrast esophagrams showed patency and no leak. All anastomoses withstood pressures well over 13 kPa without leak. Histopathology showed epithelialized circular scar tissue.

CONCLUSION

Magnetic compression anastomoses of the esophagus using our specially-designed magnets are formed between the 8th and 10th postoperative day, are patent and mechanically resistant to supraphysiologic intraluminal pressures. These data lay the basis for a potential clinical application in patients born with esophageal atresia.

LEVEL OF EVIDENCE

Not applicable (experimental animal study).

Endoscopic applications of magnets for the treatment of gastrointestinal diseases

Endoscopic treatment of gastrointestinal diseases has developed rapidly in recent years, due to its minimally invasive nature. One of the main contributing factors for this progress is the improvement of endoscopic instruments, which are essential for facilitating safe and effective endoscopic interventions. However, the slow learning curve required in the implementation of many advanced endoscopic procedures using standard devices is associated with a high risk of complications. Other routine procedures may also be complicated by unexpected difficulties. Based on the ferromagnetic properties of many objects, both internal and external magnetic devices have been developed and applied for multiple endoscopic interventions. The applications of magnets, mainly including compression, anchoring and traction, facilitate many difficult procedures and make it feasible to operate procedures that were previously impossible. Other novel endoscopic applications, such as magnetic nanoparticles, are also under development. In this article, we reviewed published studies of endoscopic applications of magnets for the treatment of gastrointestinal diseases such as precancerous lesions and cancer, obstruction, stricture, congenital and acquired malformations, motility disorders, and ingestion of foreign bodies. Since several endoscopic applications of magnets may also be relevant to surgery, we included them in this review.

Surgical treatment and major complications Within the first year of life in newborns with long-gap esophageal atresia gross type A and B - a systematic review

BACKGROUND

The surgical repair of long-gap esophageal atresia (LGEA) is still a challenge and there is no consensus on the preferred method of reconstruction. We performed a systematic review of the surgical treatment of LGEA Gross type A and B with the primary aim to compare the postoperative complications related to the different methods within the first postoperative year.

METHODS

Systematic literature review on the surgical repair of LGEA Gross type A and B within the first year of life published from January 01, 1996 to November 01, 2016.

RESULTS

We included 57 articles involving a total of 326 patients of whom 289 had a Gross type A LGEA. Delayed primary anastomosis (DPA) was the most applied surgical method (68.4%) in both types, followed by gastric pull-up (GPU) (8.3%). Anastomotic stricture (53.7%), gastro-esophageal reflux (GER) (32.2%) and anastomotic leakage (22.7%) were the most common postoperative complications, with stricture and GER occurring more often after DPA (61.9% and 40.8% respectively) compared to other methods (p < 0.001).

CONCLUSION

The majority of patients in this review were managed by DPA and postoperative complications were common despite the surgical method, with anastomotic stricture and GER being most common after DPA.

LEVEL OF EVIDENCE

Systematic review of case series and case reports with no comparison group (level IV).

Use of Magnets as a Minimally Invasive Approach for Anastomosis in Esophageal Atresia: Long-Term Outcomes

Introduction: The majority of esophageal atresia (EA) patients undergo surgical repair soon after birth. However, factors due to patient characteristics, esophageal length, or surgical complications can limit the ability to obtain esophageal continuity. A number of techniques have been described to treat these patients with "long-gap" EA. Magnets are a nonsurgical alternative for esophageal anastomosis. The purpose of this study was to report long-term outcomes for the use of magnets in EA. Materials and Methods: Between July 2001 and December 2017, 13 patients underwent placement of a magnetic catheter-based system under fluoroscopic guidance at six institutions. Daily chest radiographs were obtained until there was union of the magnets. Magnets were then removed and replaced with an oro- or nasogastric tube. Complications and outcomes were recorded. The average length of follow-up was 9.3 years (range 1.42-17.75). Results: A total of 85% of the patients had type A, pure EA, and 15% had type C with previous fistula ligation. The average length of time to achieve anastomosis was 6.3 days (range 3-13). No anastomotic leaks occurred, and all of the patients had an expected esophageal stenosis that required dilation given the 10F coupling surface of the magnets (average 9.8, range 3-22). Six patients (46%) had retrievable esophageal stents, and two underwent surgery; yet all maintained their native esophagus without interposition. A total of 92% were on full oral feeds at the time of follow-up. Conclusion: The use of magnets for treatment of long-gap EA is safe and feasible and accomplished good long-term outcomes. The main complication was esophageal stricture, although all patients maintained their native esophagus. A prospective observational study is currently enrolling patients to evaluate the safety and benefit of a catheter-based magnetic device for EA.

Beyond Magnamosis: A Method to Test Sutureless Esophageal Anastomotic Devices in Living Swine by Creating an Esophageal Bypass Loop for Natural Oral Nutrition

Introduction: Thoracoscopic esophageal atresia repair has become increasingly popular, but is still limited to a few expert centers and has some challenges and shortcomings. One of them has a longer operation time compared with conventional thoracotomy. Magnetic compression anastomosis may contribute toward shorter operation times by avoiding the time-consuming anastomotic suturing. We aimed to establish a method of testing sutureless anastomoses in parallel to having swine eating the natural way. Materials and Methods: We used four juvenile Pietrain swine-aged 8 weeks, weighing 15 kg-to establish a living animal model after preceding cadaver tests. Esophagi were fully mobilized through right-sided thoracotomy to gain sufficient length to create an esophageal loop that served as a bypass for food after magnet deployment. Six hours later, patency of the bypass esophageal loop was assessed by passing an orogastric tube and by allowing swine to drink methylene blue-stained water. We also tested the device stability using the classical burst pressure test. Results: The esophageal lumen was patent for feeding tube. Swine were able to drink and methylene blue colored fluid reached the stomach. Clinical signs of obstruction such as regurgitation or coughing were absent. Magnets sustained burst pressures up to 200,000 Pascal until they became disrupted. At 6 hours after magnet placing, we already saw subtle esophageal mucosa erosions indicating the beginning of anastomotic formation. Conclusion: This animal model is useful to test different magnet designs for sutureless esophageal anastomosis or even future devices for in vivo tissue engineering.

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.

Laparoscopic Magnetic Compression Biliojejunostomy: A Preliminary Clinical Study

BACKGROUND

Magnetic compression anastomosis is a feasible and effective method for bilioenteric anastomosis (BEA) in animal model. The objective of the present study was to report our initial clinical experience in laparoscopically magnetic compression bilioenteric anastomosis (LMC-BEA).

METHODS

Patients with obstructive jaundice who were candidates for LMC-BEA were prospectively enrolled from 2013 to 2015. All the procedures were performed laparoscopically. A mother magnet and drainage tube were placed in the proximal bile duct and tightened by a purse suture after dissection of the common bile duct. The drainage tube was introduced into the jejunal lumen at the anastomotic site and guided a daughter magnet to approximate the mother magnet. The two magnets mated at the anastomotic site. All the patients were routinely followed up for magnets discharge till the end of the study.

RESULTS

In total, four patients with malignant obstructive jaundice and one patient with benign biliary stricture were included. The median age was 70 y (range, 49-74 y). The median time for LMC-BEA was 12 min (range, 8-15 min). A complete anastomosis was confirmed after a median time of 21 d (range, 5-25 d) postoperatively by cholangiography via drainage tube. The magnets were expulsed around 41 d after surgery (range, 12-47 d) postoperatively. With a median follow-up of 313 d (range, 223-1042 d), no complications associated with magnetic anastomosis was documented, such as bile leakage or anastomotic stricture.

CONCLUSIONS

Magnetic compression is a promising alternate method for laparoscopic BEA. Among the five patients undergoing LMC-BEA, no one developed anastomotic complications.

Magnetic Compression Anastomosis in Long-Gap Esophageal Atresia Gross Type A: A Case Report

Esophageal atresia (EA) Gross type A (long-gap without tracheoesophageal fistula) is a rare and a surgical challenging form of EA that constitutes ∼6% of the children born with EA. We present the seventh reported case with successful esophagoesophagostomy obtained by magnetic compression of a long-gap EA type A without thoracotomy.

A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep learning curve. The introduction of the cuff technique for anastomosis of the portal vein (PV) and infrahepatic vena cava (IHVC) has significantly simplified the transplant procedure in rats. However, due to the short anterior wall of the recipients' suprahepatic vena cava (SHVC), the cuff technique is very difficult to use for the reconstruction of the SHVC. Most researchers in this field still use the hand-suture technique for SHVC reconstruction, which makes it the bottleneck step in rat orthotopic liver transplantation. The magnetic anastomosis technique (i.e., magnamosis) is a method of connecting two vessels using the attractive force between two magnets. Our recent study has shown that the magnetic anastomosis technique is superior to the hand-suture technique for SHVC reconstruction in rats. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using the novel magnetic anastomosis technique. In this model, the reconstruction of the PV and IHVC was performed by the standard cuff technique, while the reconstruction of the bile duct (BD) was performed by a stent technique. The hepatic re-arterialization was not performed. The magnetic anastomosis technique made SHVC reconstruction much easier and significantly shortened the anphepatic phase. After a reasonable learning curve, even researchers without advanced microsurgical skills can produce reliable and reproducible results using this rat model of OLT.

Advanced Roux-en-Y hepaticojejunostomy with magnetic compressive anastomats in obstructive jaundice dog models

BACKGROUND

Although commonly used procedure, Roux-en-Y hepaticojejunostomy (RYHJ) remains to be complicated, time consuming, and has a relatively poor prognosis. We designed the magnetic compressive anastomats (MCAs) to perform RYHJ more efficiently and safely.

MATERIALS AND METHODS

36 dogs were divided into two groups randomly. After obstructive jaundice model construction, RYHJ was performed with MCAs in study group or by hand-sewn in control group. Both groups were followed for 1, 3, and 6 months after RYHJ. The liver function and postoperative complications were recorded throughout the follow-up. At the end of each time point, dogs were sent for magnetic resonance imaging (MRI) and sacrificed. Anastomotic samples were taken for anastomotic narrowing rate calculation, histological analyses, tensile strength testing, and hydroxyproline content testing.

RESULTS

The anastomotic construction times were 44.20 ± 23.02 min in study group, compared of 60.53 ± 11.89 min in control group (p < 0.05). The liver function recovered gradually after RYHJ in both groups (p > 0.05). All anastomats were expelled out of the body in 8.81 ± 2.01 days. The gross incidence of morbidity and mortality was 33.3% (6/18) and 16.7% (3/18) in study group compared with 38.9% (7/18) and 22.2% (4/18) in control group (p > 0.05), and there is no single case of anastomotic-specific complications happened in study group. The narrowing rates of anastomosis were 14.6, 18.5, and 18.7% in study group compared with 35.4, 36.9, and 34% in control group at 1st, 3rd, and 6th month after RYHJ (p < 0.05). In study group, preciser alignment of tissue layers and milder inflammatory reaction contributed to the fast and better wound healing process.

CONCLUSION

Perform RYHJ with MCAs is safer, more efficient than by hand-sewn method in obstructive jaundice dog models.

Novel use of porcine extracellular matrix in recurrent stricture following repair of tracheoesophageal fistula

Anastomotic stricture is a common complication following repair of esophageal atresia (EA). Many factors are thought to contribute to stricture formation and a variety of management techniques have been developed. In this case report, we describe the treatment of a recurrent anastomotic stricture following repair of long-gap esophageal atresia. Porcine bladder extracellular matrix (ECM) was mounted on a stent and delivered endoscopically to the site of recurrent stricture. An appropriate positioning was confirmed using direct endoscopic visualization and intra-operative fluoroscopy. The patient recovered well with persistent radiographic and functional improvements in previous stricture.