| In biliary tract surgery, biliary stone disease, neoplasms of biliary tract, bile duct injury often brought about interruption of continuity, and after repeated biliary tract surgery, and it also added to the possibility of bile duct injury. Because of surgical suture, scar contracture, the occurrence of tumors, tcholecystojejunostomy stenosis would be caused in reconstruction of the bile duct. The sphincter of Oddi contractile could not play a role it should be, so that the reflux occurred repeatedly, resulting in retrograde infection of biliary tract and the liver bile sclerosis and other serious complications. After surgical reconstruction of the biliary tract and alternative structures, often because they did not have a good biological properties, or could not be a good simulation of the physiological function of biliary tract, biliary tract disease could not be resolved well in patients with poor prognosis, even leaded to more serious post-operative complications. How to achieve a scientific and rational surgical biliary reconstruction had become the current bottleneck in the development of biliary tract surgery. Developing not only stability both in vitro and in vivo, but also a very good compatible with the organism, which could play a physiological function of biliary artificial bile duct, it became an urgent scientific research projects.Development of artificial bile duct, first of all need a stable and reliable screening of biological tissue-engineered materials, so that it could play in the biological body well the role of tissue engineering scaffolds. Fluoroelastomer- 246B was ternary structural copolymer of vinylidene, fluoride, tetrafluoroethylene, hexafluoro, propylene.Characteristics of fluoroelastomer-246B was a kind of linear flexible polymers, molecular chain between the price of power at small, flexible, and so they had good processing characteristics. It had a certain stability, did not give rise to inflammation and foreign body reaction, non-carcinogenic, and could fight against mechanical stress. It did not give rise to cancer or allergic reaction. Its unique structure, easy modification and easy processing, and biological characteristics of good characteristics, complyed with the basic characteristics of materials,which would be implanted into the body. First of all, in accordance with different anti-reflux anatomical structure in vivo, in accordance with the physiological function of the bile, "pressure control, orientation and opening up", fluoroelastomers 246B was produced with different structure of the artificial valve pipeline. Thus I made a bionic artificial bile duct with the valve,which had "directed open" function to simulate the patency of biliary tract and anti-reflux of bile and intestinal physiological function. I carried out the artificial bile duct patency experiment, anti-reflux experiments and stability experiments in vitro, which with a kind of vein valve, active valve and without valve. Patency in vitro experiments showed that ,whether there was a valve or no valve structure of the artificial bile duct, the liquid outflow speet up the pace accompanied by the liquid in the trickle-down in the process of gradually accelerating the speed, and the outflow speed and the speed of the same trickle-down. Compared to artificial straight duct there was no difference in patency. The design of the two bionic valve on the basis of the processing was as easily as possible in the production, and its simple structural design ensured that the patency of the valves and bile duct. In anti-reflux in vitro experiments, two types of bionic valves had different characteristics of the anti-reflux. When bile flowed reversely in the liquid, the valve fully opened as a pocket-like, so that the liquid form of the eddy current in the opposite direction, slow down after the reverse flow can be an effective anti-reflux. Stability in vitro study carried out on fresh fluoroelastomers 246B immersion, conventional disinfection methods and experimental rats implanted clear fluoroelastomers 246B, which showed that the fluoroelastomers 246B could be used as suitable materials to the artificial bile duct. After that, I implanted bionic artificial pipeline made by fluoroelastomer-246B as bile ducts into dogs, as a further demonstration of the feasibility of alternatives to bile. These two pipelines, and the straight tube which did not contain any anti-reflux structure , were implanted into dogs randomly, divided into straight tube group (group A), venous valve group (group B)and the valve group (group C). By comparing the TB, ALT, AST values,the pipe sediments and the characteristics of gallbladder inflammation after operation at the 1st and 7th, we could observe the fluency of pipeline and anti-reflux situation.Contrasting with TB, ALT, AST of group A, B, C after the 1st day and 7th, there were no significant changes, no significant differences (P>0.05). Contrasting with TB, ALT, AST betweenA, B, C groups after the 1st day and 7th ,there were no significant changes, no significant differences (P>0.05). To observe the sediments within three different pipeline, group A was half-pipe blockage, and had more yellow-green sediments at the pipe wall, group B had slightly yellowish sediments at the top of valve, some white floc sediments within the pipe, no significant sediment on the valves, group C had some yellow-green sediments on the pipe wall near the valve, bile mixed with some white floc. Dogs in vivo showed that the artificial bile duct which had different structures of valve, all had good patency. In the short-term observation, they were all with a certain degree of anti-reflux performance, played a similar function of bionic valve with Oddis sphincter.In summary, the innovations and the important experimental methods used were: 1. Combined normal human physiological characteristics of biliary tract, we designed a vein valve and active valve structure, which made the artificial bile duct played a certain role in anti-reflux on the basis of no affecting the normal patency; 2. In the design of operation program, combined with the characteristics of dog's anatomy, we conducted a design of gallbladder-artificial bile duct-duodenum, both to ensure the smooth conduct of the trial, but also by observing the performance of gallbladder inflammation, more directly to reflect the effection of potential of fluid and bile reflux to the biliary system.The tests made the analysis of possibility fluoroelastomers246B as the artificial bile duct, and combined with clinical. Research and development through animal experiments, patency and the role of anti-reflux of different forms of artificial channels were studyed ,which demonstrated that the artificial bile duct as a substitute to play a scientific and rational role in physiology. This was suitable for further clinical research ,and of alternatives to the biliary tract ,which was a major significance, opening up the future development of biliary surgery new direction.
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