Self-expansion in-vivo absorption biliary tract stent

Abstract

The invention discloses a self-expansion in-vivo absorption biliary tract stent, which is made of a biological absorbable material and does not need to be taken out through an operation after being implanted into a body. By means of the special structure, the overall length of the stent is not changed when the stent shrinks and expands, the length of the stent needing to be implanted is conveniently judged, and the release position is controlled. According to the technical scheme, the stent is characterized by comprising a plurality of linear supporting rods and a plurality of sets of supporting pieces, and the linear supporting rods and the sets of supporting pieces are all made of biological absorbable materials; the multiple linear supporting rods are arranged in parallel in the circumferential direction, the multiple sets of supporting pieces are arranged along the linear supporting rods at equal intervals, each set of supporting pieces comprises fusiform supporting rings with the same number as the linear supporting rods, and each fusiform supporting ring comprises two tip ends and two (-shaped arches. The fusiform supporting rings in the same group of supporting pieces are fixedly connected in sequence, the connecting positions are located in the middles of the (-shaped arches of the fusiform supporting rings, one tip end of each fusiform supporting ring is fixedly connected with the corresponding linear supporting rod, and the other tip end of each fusiform supporting ring is in sliding connection with the corresponding linear supporting rod.

Description

technical field [0001] The invention relates to the technical field of medical stents, in particular to a self-expandable in vivo absorbable biliary tract stent. Background technique [0002] The biliary system has the functions of secreting, storing, concentrating and transporting bile, and plays an important role in regulating the discharge of bile into the duodenum. Biliary obstruction is a disease with a high mortality rate in surgical acute abdomen, most of which are secondary to bile duct stones and biliary ascariasis, but sometimes lesions such as bile duct stricture and bile duct tumors can also be secondary to this disease. The above diseases cause bile duct obstruction, cholestasis, and secondary bacterial infection. [0003] If bile duct infection occurs on the basis of obstructive disease, the bile duct mucosa will be congested with water, leading to aggravated symptoms of bile duct obstruction, the bile will gradually become purulent, the pressure in the bile d...

AI Technical Summary

Problems solved by technology

[0007] Compared with metal stents, plastic stents have poorer biocompatibility, which can easily cause symptoms such as bleeding and tissue hyperplasia. Plastic stents can easily lead to the formation of bacterial biofilms and biliary sludge in the biliary tract. Bacteria and sticky protein substances can form bacterial biofilms and deposit on the Bacteria and their products, calcium bilirubin, and calcium palmitate accumulate on the surface of the stent, leading to the formation of biliary sludge, which leads to blockage of the stent

[0008] Metal stents are less likely to form bacterial film and biliary sludge than plastic stents, but granulation tissue hyperplasia, tumor growth, tissue reaction hyperplasia and other reasons can cause tissues to enter the bile duct lumen through the stent mesh and cause blockage

[0009] Existing metal stents generally adopt an integrated network structure formed by laser cutting, or a network structure formed by braiding metal wires. The overall length of the metal stent with this structure will become longer when it shrinks radially, and its overall length will become longer when it expands radially. Its overall length will be shortened, making it difficult to judge the optimal length of the implanted stent, and it will be difficult to control the release position during the implantation process. If necessary, multiple releases are required to achieve the correct position; in addition, some integrated When the bending angle of the biliary tract is relatively large, the chemically formed metal stent will cause the stent to be narrowed at the bend, making it impossible to open the biliary tract to maintain patency

[0010] Although the bio-coated stent has solved the problem of tissue hyperplasia, it still has other defects of the above-mentioned metal stents. In addition, the bio-coated stent is prone to stent displacement, resulting in cholangitis, stent blockage and chronic pancreatitis. aggravation of symptoms

Images