Choledochojejunostomy with an innovative magnetic compressive anastomosis: How to determine optimal pressure?

Endoscopic application of magnetic compression anastomosis: a review

Magnetic compression anastomosis (MCA) is a new method that provides sutureless passage construction for tubular organs. Due to the high recurrence rate of conventional endoscopic treatment and the high morbidity and mortality of surgical procedures, the MCA technique shows promise. The aim of this review is to comprehensively examine the literature related to the use of MCA in different gastrointestinal diseases over the past few years, categorizing them according to the anastomotic site and describing in detail the various methods of magnet delivery and the clinical outcomes of MCA. MCA is an innovative technique, and its use represents an advancement in the field of minimally invasive interventions. Comparison studies have shown that the anastomosis formed by MCA is comparable to or better than surgical sutures in terms of general appearance and histology. Although most of the current research has involved animal studies or studies with small populations, the safety and feasibility of MCA have been preliminarily demonstrated. Large prospective studies involving populations are still needed to guarantee the security of MCA. For technologies that have been initially used in clinical settings, effective measures should also be implemented to identify, even prevent, complications. Furthermore, specific commercial magnets must be created and optimized in this emerging area.

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.

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.

Surprising neutral effect of shorter staple cartridges in laparoscopic sleeve gastrectomy

BACKGROUND

Consensus agreements regarding laparoscopic sleeve gastrectomy (LSG) advise against using staple loads less than 1.5 mm in closed staple height. However, few data exist to support this recommendation. We hypothesized that using staples with a shorter closed height would actually decrease incidence of intraoperative and postoperative bleeding during LSG, while not increasing the incidence of leak.

METHODS

All LSG cases for a single institution from 1/1/2014 to 12/31/2019 were exported for analysis. Two cohorts were established: 1. 'Green/Blue' group was cases in which no white cartridges were used and 2. 'White' group was cases in which any white cartridges were used. Demographic variables, procedural characteristics, hospital length of stay, and postoperative outcomes were compared between groups.

RESULTS

The study populations included 1710 patients, 974 in the green/blue group and 736 in the white cartridge group. There were no significant differences in postoperative leak, bleed, stricture, readmission, or death while using white staple loads as compared with the standard combination of blue and green loads.

CONCLUSION

Using staples with a shorter closed height during LSG did not impact the postoperative bleeding or leak rate. The impact from selection of shorter staples to achieve more tissue compression may be limited.

Physical Bases, Indications, and Results of the Use of Magnets in Digestive Surgery: A Narrative Review

Background: The use of magnetic devices in digestive surgery has been a matter of debate in recent years. The aim of this review was to describe the physical bases, indications, and results of the use of magnets in digestive surgery. Methods: A review of the literature was performed using Scopus, PubMed, ScienceDirect, and SciELO databases considering as inclusion criteria all articles published since 2007 to date, describing the physical basis of magnetic assisted surgery and those that describe the surgical procedure, including case reports, as well as, articles on humans and experimental animals. Results: Sixty-four studies were included, 15 detailing aspects on the physical basis and 49 about indications and results. Magnets are currently used to perform fixed traction, mobilizing structures, and anastomosis in humans and experimental animals. Conclusions: The use of magnets in digestive surgery has shown good results, and no complications arising from their use have been reported. However, more prospective and randomized studies that compare magnetic surgery and conventional techniques are needed.

Cholangiojejunostomy Using a Novel Magnamosis Device: Initial Clinical Results

BACKGROUND

Cholangiojejunostomy (CJ) is a popular operation; however, no specific anastomotic device is available. A novel magnamosis device for CJ was developed in 2017; here, we evaluated the feasibility and safety of the device.

METHODS

Between January 2017 and December 2019, 23 patients who underwent CJ using a novel magnamosis device were enrolled. For the CJ: the parent magnet was placed in the proximal duct, and the purse-string suture was tightened over the rod of the parent magnet. The magnamosis device was introduced into the jejunum, and the mandrel penetrated the jejunum at the anastomotic site, before insertion into the rod of the parent magnet. After rotating the knob, the distance between two magnets was shortened enough to achieve coupling.

RESULTS

Sixteen patients (69.6%) underwent open CJ, while 7 (30.4%) underwent laparoscopic CJ; 21 patients (91.3%) underwent choledochojejunostomy, and 2 (8.7%) underwent right or left hepatic duct jejunostomy. The mean time for completion of CJ was 9.2±2.5 min; it was significantly shorter for open CJ than for the laparoscopic way (8±1.2 min vs. 11.8±2.5 min, P<0.05). Only one patient (4.3%) suffered bile leakage after operation and was cured by conservative treatment. The magnets were discharged with a postoperative duration of 66.7±47.2 days, with a 100% expulsion rate. After a median follow-up of 15 months, only one patient (4.3%) developed inflammatory anastomotic stricture.

CONCLUSION

The novel magnamosis device is a simple, safe, and effective modality for CJ.

Bile duct reconstruction using scaffold-free tubular constructs created by Bio-3D printer

Introduction

Biliary strictures after bile duct injury or duct-to-duct biliary reconstruction are serious complications that markedly reduce patients’ quality of life because their treatment involves periodic stent replacements. This study aimed to create a scaffold-free tubular construct as an interposition graft to treat biliary complications.

Methods

Scaffold-free tubular constructs of allogeneic pig fibroblasts, that is, fibroblast tubes, were created using a Bio-3D Printer and implanted into pigs as interposition grafts for duct-to-duct biliary reconstruction.

Results

Although the fibroblast tube was weaker than the native bile duct, it was sufficiently strong to enable suturing. The pigs' serum hepatobiliary enzyme levels remained stable during the experimental period. Micro-computed tomography showed no biliary strictures, no biliary leakages, and no intrahepatic bile duct dilations. The tubular structure was retained in all resected specimens, and the fibroblasts persisted at the graft sites. Immunohistochemical analyses revealed angiogenesis in the fibroblast tube and absence of extensions of the biliary epithelium into the fibroblast tube's lumen.

Conclusions

This study's findings demonstrated successful reconstruction of the extrahepatic bile duct with a scaffold-free tubular construct created from pig fibroblasts using a novel Bio-3D Printer. This construct could provide a novel regenerative treatment for patients with hepatobiliary diseases.

Fedora-type magnetic compression anastomosis device for intestinal anastomosis

BACKGROUND

Although previous studies have confirmed the feasibility of magnetic compression anastomosis (MCA), there is still a risk of long-term anastomotic stenosis. For traditional MCA devices, a large device is associated with great pressure, and eventually increased leakage.

AIM

To develop a novel MCA device to simultaneously meet the requirements of pressure and size.

METHODS

Traditional nummular MCA devices of all possible sizes were used to conduct ileac anastomosis in rats. The mean (± SD) circumference of the ileum was 13.34 ± 0.12 mm. Based on short- and long-term follow-up results, we determined the appropriate pressure range and minimum size. Thereafter, we introduced a novel “fedora-type” MCA device, which entailed the use of a nummular magnet with a larger sheet metal.

RESULTS

With traditional MCA devices, the anastomoses experienced stenosis and even closure during the long-term follow-up when the anastomat was smaller than Φ5 mm. However, the risk of leakage increased when it was larger than Φ4 mm. On comparison of the different designs, it was found that the “fedora-type” MCA device should be composed of a Φ4-mm nummular magnet with a Φ6-mm sheet metal.

CONCLUSION

The diameter of the MCA device should be greater than 120% of the enteric diameter. The novel “fedora-type” MCA device controls the pressure and optimizes the size.

Biomechanical and Performance Evaluation of Magnetic Elliptical-Ring Compressive Anastomoses

BACKGROUND

After magnetic compressive anastomosis, anastomat passage through the narrow channels of the digestive tract is difficult owing to the device's large volume. Such passage can lead to mechanical damage to the digestive tract or anastomat's unstable excretion time. This article presents a new magnetic compressive anastomotic approach.

METHODS

A magnetic elliptical-ring compressive anastomat was designed and evaluated for placement and passage in vitro. Nine young adult dogs underwent laparotomy with intestinal tissue side-to-side anastomosis. Four different groups of magnetic compressive anastomats of two different magnetic force levels (20 N or 30 N) and shapes (round or elliptical) were implanted into each dog simultaneously. Three dogs were euthanized on each of postoperative day 1, day 4, and day 7. Anastomoses were then compared with respect to histology and tensile fracture force.

RESULTS

The magnetic elliptical-ring compressive anastomat was functional but produced less obstruction compared to its round counterpart during passage through the esophagus and intestine. Nine dogs underwent successful surgery and harvesting of 30 total anastomoses. Histology of anastomotic tissue showed that, along the newly formed tunnel connecting the two sides of anastomotic tissues, compressed tissues became thinner and fell off, and initial anastomoses formed on the seventh postoperative day. There were large differences in tensile fracture force among the anastomoses formed by magnets with different magnetic forces of the same structure. However, the magnetic compressive anastomat structure did not affect anastomotic repair during magnetic compression anastomosis.

CONCLUSIONS

The magnetic elliptical-ring compressive anastomat is an efficient anastomotic device that can be used easily and with good passage. The device has good biomechanical properties and can be used with endoscopy to reduce operative time.

Magnetic compression anastomosis for biliojejunostomy and pancreaticojejunostomy in Whipple's procedure: An initial clinical study

BACKGROUND AND AIM

Magnetic anastomosis has been attempted in biliary and intestinal reconstruction. The objective of the current study was to introduce an initial clinical use of magnetic compression anastomosis for pancreaticojejunostomy and biliojejunostomy in Whipple's procedure.

METHODS

Patients with peri-ampullary carcinoma and dilated bile and pancreatic ducts were prospectively enrolled from 2016 to 2017. After pancreaticoduodenectomy, an appropriate mother magnet and drainage tube was placed in the proximal bile duct and pancreatic duct. The daughter magnets were introduced to mate with the mother magnets at the anastomotic sites. A close postoperative surveillance and routine cholangiopancreaticography via the drainage tube were performed.

RESULTS

One female and three male patients with a median age of 69 years (range, 57-77) were included. The diameter of the common bile ducts and pancreatic ducts ranged from 8 to 15 mm, and 7 to 10 mm, respectively. The median time duration for biliojejunostomy and pancreaticojejunostomy was 7 (range, 5-8 min) min and 9 (range, 8-10 min) min, respectively. The median time of biliojejunostomy and pancreaticojejunostomy formation was 17 (range, 15-21 days) days and 11 (range, 10-18 days), respectively. With a median follow up of 313 days, one patient developed biliary anastomotic stricture at 11 months after surgery, and underwent stent placement via percutaneous transhepatic drainage sinus, and recovered well.

CONCLUSIONS

Magnetic anastomosis is safe, effective, and simple for both biliojejunostomy and pancreaticojejunostomy in Whipple's procedure.

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.

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.

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.