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The recent development of tough tissue adhesives has stimulated intense interests among material scientists and medical doctors. However, these adhesives have seldom been tested in clinically demanding surgeries. Here we demonstrate adhesive anastomosis in organ transplantation. Anastomosis is commonly conducted by dense sutures and takes a long time, during which all the vessels are occluded. Prolonged occlusion may damage organs and even cause death. We formulate a tough, biocompatible, bioabsorbable adhesive that can sustain tissue tension and pressurized flow. We expose the endothelial surface of vessels onto a gasket, press two endothelial surfaces to the adhesive using a pair of magnetic rings, and reopen the bloodstream immediately. The time for adhesive anastomosis is shortened compared to the time for sutured anastomosis. We have achieved adhesive anastomosis of a great vein in transplanting the liver of a pig. After the surgery, the adhesive is absorbed, the vein heals, and the pig lives for over one month.

Magnetic anchoring technology provides a new development opportunity for current minimally invasive surgery. The magnetic anchoring abdominal video system based on this technology can effectively improve the operability and minimally invasiveness of single-port laparoscopic surgery. The development history of magnetically anchored abdominal video system was reviewed, and the design features and deficiencies of various types of magnetically anchored video devices were compared and analyzed. The evolution characteristics of the magnetic anchored video system are explained from minimally invasive and intelligent perspectives, and the challenges and opportunities of magnetic anchored video system are summarized and prospected.

Magnetic compression anastomosis (MCA) is a revolutionary minimally invasive method to perform choledochocholedochostomy in patients with benign biliary stricture (BBS). We conducted MCA for the treatment of severe BBS that could not be treated by conventional methods. Patients with BBSs that could not be treated using conventional treatments were included. All patients underwent percutaneous transhepatic biliary drainage (PTBD) before MCA, and underwent cholangiography via simultaneous PTBD and endoscopic retrograde cholangiopancreatography (ERCP). The MCA device consisted of a parent and a daughter magnet. The daughter magnet was delivered via the PTBD route to the proximal end of the obstruction, and the parent magnet was delivered via ERCP to the distal end of the obstruction. After recanalization, the MCA device was removed, and biliary stenting (or PTBD) was performed for at least 6 months. Of the 9 patients (age 49 ± 12.9 years), 6 had undergone orthotopic liver transplantation. MCA was successful in all 9 patients. The stricture length was 3 ± 1.7 mm, and recanalization occurred after 16.3 ± 13.2 days. Multiple plastic stents (4 patients), fully covered self-expandable metallic stents (4 patients), or PTBD (1 patient) was used after recanalization. Two mild adverse events occurred (cholangitis, 1 patient; biliary bleeding, 1 patient), but were resolved with conservative treatment. Stents were retrieved after > 6 months, and no stenosis occurred during 2–66 months of stent-free follow-up. The MCA technique is a revolutionary method for choledochocholedochostomy in patients with severe BBS unresponsive to conventional procedures.

For reducing the error of the Distance Vector-Hop (DV-Hop) positioning algorithm in the hop-distance and estimation coordinates and enhance the localization accuracy of the underground mine, a novel method that introduces the modified whale optimization algorithm (WOA) to optimize the DV-Hop is proposed. Firstly, adopt the average distance per hop is used to amend the hop-distance from the node to be located and each beacon node to minimal the error of the estimation distance. Then, employ the information entropy to disturbance the parameters of WOA, which can make the individual of whales evenly distributed and escape from getting into local optimum when searching the optimal solution. Finally, the simulation shows that the improved means is able to reduce the node location error rate by 15.07% compared to no modified algorithm, and the positioning accuracy of DV-Hop algorithm is enhanced without adding other hardware devices.

Magnetic compression anastomosis (MCA) has been appreciated as an innovative alternative to manual suturing in vascular reconstruction. However, magnetic devices have limitations in their applications. The present study aimed to introduce a newly developed magnetic device for end-to-end vascular anastomosis. Twenty male New Zealand rabbits were randomly assigned to receive end-to-end postcaval vein anastomosis using either a newly designed MCA device (Group MCA) or continuous-interrupted suturing (Group CIS). The anastomotic patency was evaluated by Doppler or venography immediately, 1 week, and 12 weeks after surgery. Anastomotic quality was evaluated gross and microscopic histological study 12 weeks after surgery. The procedure was successfully performed and all animals survived until sacrifice. The duration of surgery and anastomosis time in Group MCA were significantly shorter compared to Group CIS (all p 0.001), and the incidence of anastomotic patency and postoperative morbidity were comparable between the two groups (all p 0.05). Hematoxylin-eosin staining showed that anastomotic intima from Group MCA was much smoother with more regularly arranged endothelial cells than from compared to the Group CIS. A novel MCA device was successfully applied in rabbit vascular anastomosis. We demonstrated the reliability and effectiveness of this newly developed MCA in this study.

Laparoendoscopic single-site surgery and natural orifice transluminal endoscopic surgery attempt to reduce transabdominal port sites. These require all instruments to pass through a single access point, leading to instruments collide or work at unfamiliar angles. Thus, we designed an internal grasper under magnetic anchoring guide system (MAGS) platform and investigated its utility and operability. We measured the configuration for magnetic force decay over distance using a standardized, ex vivo laboratory testing apparatus. An electronic balance was used to measure the force of the gallbladder pull in ten patients with gallbladder stones. One pig (11 mm abdominal wall thickness) underwent a compressed trial of MAGS platform. The device was left in place for 20 min before tissue sections were harvested, and histologic assessment was performed. The utility and operability were investigated in four pigs (38–280 kg weight). The magnetic attraction force decayed exponentially over distance; the force of pulling gallbladder was 7.46 ± 0.54 N. This pairing of components allowed for coupling to a theoretical distance of 10 mm. No gross tissue damage was observed. H–E stain showed no necrosis in all specimens. One failed due to wall thickness of 45 mm. Others showed the critical view, triangulation of instruments was obtained, and instrument collision or “sword fighting” was reduced. The MAGS platform overcomes limitations such as collisions and lack of triangulation, reduces transabdominal port sites, and is easy to operate. However, our internal grasper requires the abdominal wall thickness below 10 mm.

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

This study evaluated a novel magnetic compression technique (magnamosis) for creating a portacaval shunt in a canine model of portal hypertension, relative to traditional manual suture. Portal hypertension was induced in 18 dogs by partial ligation of the portal vein (baseline). Six weeks later, extrahepatic portacaval shunt implantation was performed with either magnetic anastomosis rings, or traditional manual suture (n = 9, each). The two groups were compared for operative time, portal vein pressure, and serum biochemical indices. Twenty-four weeks post-implantation, the established anastomoses were evaluated by color Doppler imaging, venography, and gross and microscopic histological examinations. Anastomotic leakage did not occur in either group. The operative time to complete the anastomosis for magnamosis (4.12 ± 1.04 min) was significantly less than that needed for manual suture (24.47 ± 4.89 min, P

To assese the healing of stoma after magnetic anastomosis for the reconstruction of biliary-enteric continuity under severe inflammation.Acute bile duct injury was constructed as a bile peritonitis model in mongrel dogs (n=32). Magnetic anastomosis (group A, n=16) and traditional suture anastomosis (group B, n=16) were performed to reconstruct the biliary-enteric continuity in one stage. Half of the dogs in each group were euthanized on the 30th postoperative day, and the other half on the 90th postoperative day to harvest the stoma region. The healing conditions of the stoma after the 2 anastomotic approaches were observed with naked eyes, under light microscope and scanning electron microscope.The stoma leakage rate (50% versus 0% on the 30th postoperative day, 37.5% versus 12.5% on the 90th postoperative day, both P0.05) and stenosis degree (13.9%±0.3% versus 7.1%±0.3% on the 30th postoperative day, 17.2%±0.4% versus 9.4%±0.4% on the 90th postoperative day, both P0.01) were significantly higher in group B than in group A. Compared with traditional manual anastomoses, the histological analysis under light and electron microscope showed a more continuous stoma with more regular epithelium proliferation and collagen arrangement, less inflammation in group A.Magnetic anastomosis stent ensures better healing of the stoma even under the circumstance of severe inflammation.

The characteristics of the PM2.5 concentration in surgical smoke produced by operating on different human tissues during hemihepatectomy were explored to provide a reference for protective measures. Our results showed that the highest concentration of PM2.5 produced by the electrosurgical knife was the liver tissue, followed by muscle, adipose, and vascular tissue. When the single-layer disposable medical mask, double-layer disposable medical mask, and surgical particulate respirator were used to cover the sampling port of the detector, the PM2.5 concentration for all tissue types could be reduced by approximately 40%, 55% and 75%, respectively. In the liver, the average concentration of PM2.5 produced by the ultrasonic scalpel was approximately twice that produced by the electrosurgical knife, suggesting that the air pollution around the chief surgeon caused by the ultrasonic scalpel is more serious than that caused by the electrosurgical knife. Much more protective work should be given for the liver-related surgery.

The resection and reconstruction of large vessels, including the portal vein, are frequently needed in tumor resection. Warm ischemia before reconstruction might have deleterious effects on the function of some vital organs and therefore, how to reconstruct the vessels quickly after resection is extremely important. The present study was to introduce a new type of magnetic compression anastomosis (MCA) device to establish a quick non-suture anastomosis of the portal vein after resection in canines.The new MCA device consists of a pair of titanium alloy and neodymium-ferrum-boron magnet (Ti-NdFeB) composite rings. The NdFeB magnetic ring as a core of the device was hermetically sealed inside the biomedical titanium alloy case. Twelve canines were divided into two groups: a MCA group in which the end-to-end anastomoses was made with a new device after resection in the portal vein and a traditional manual suture (TMS) group consisted of 6 canines. The anastomosis time, anastomotic patency and quality were investigated at week 24 postoperatively.The portal vein was reconstructed successfully in all of the animals and they all survived. The duration of portal vein anastomosis was significantly shorter in the MCA group than in the TMS group (8.16+/-1.25 vs 36.24+/-2.17 min, P0.05). Portography and ultrasound showed that the blood flow was normal without angiostenosis or thrombosis in all of the canines. Hematoxylin-eosin staining and electron microscope scanning showed in contrast to the TMS group, MCA anastomotic intimal was much smoother with more regularly arranged endothelial cells at week 24 postoperatively.The Ti-NdFeB composite MCA device was applicable in reconstruction of large vessels after resection. This device was easy to use and the anastomosis was functionally better than the traditional sutured anastomosis.

A new system of blood flow block for control of bleeding in abdominal operation is composed of an abdominal magnetic blocking unit, an abdominal external electromagnet unit and other non-magnetic operation instrument. The abdominal external electromagnetic unit is placed in advance in the operation bed. The abdominal magnetic blocking unit can be placed directly on the ventral of the large vessels when need to blocking the abdominal large vessels during the operation. According to the non-contact suction characteristics of magnetic materials, the two magnetic units will attract each other and compression the vessels. Using this system for vascular occlusion does not need clear exposure and without separating vessel. There is the advantage of rapid, accurate and reliable for the system.