The Research Of Novel Biodegradable Esophageal Stent

Background and Aims The treatment of benign esophageal stricture is still a major problem.At present,the common treatment for benign esophageal stricture in children is balloon dilatation treatment.According to the complexity of the lesion,the child often suffers from multiple dilation procedures.In addition,benign esophageal stricture can also be treated with traditional metal stents.However,there are some serious complications in the treatment of metal stents,such as chest pain,bleeding,and perforation.What’s more,the special nature of children’s growth also determines the need for metal stents to be removed within a limited time.All of this limits its use in the treatment of benign esophageal strictures.Therefore,there is an urgent need to develop a new type of esophageal stent to provide more choices for clinical treatment.Compared to metal stents,biodegradable stents provide reliable support over a period of time while having the advantage of being degradable and avoiding postoperative removal.As a result,the pain of the child and the economic burden of the child’s family are reduced,and a new choice for the treatment of esophageal stricture is provided.This study intends to establish an animal model of esophageal stricture,and explore the development of bioabsorbable esophageal stent,and verify its practicability and feasibility.Methods Our project was divided into two parts in order to study the novel biodegradable esophageal stent for children,using New Zealand rabbits as animal model.In the first part,we established the animal model using two balloon catheters for improving the existing method.In the second part,we weaved novel biodegradable esophageal stent,strengthening its radial force and optimizing its structure.The in vitro degradation was studied by determining the change of surface morphology,radial support strength,and melting point.In addition,the new esophageal stent in vivo implantation was also carried out preliminarily.Results 1.Two balloon catheters was safer and more reliable than previous method.And the scope of injury is controllable.We can get animal model after 2 weeks.2.The radial support strength,axial shrinkage and expansion rate of the new esophageal stent is similar to commercial metal stents,and its surface coverage is even better;In the early stage,the surface morphology,radial support strength,and melting point of stent had no obvious change.And the change started from 12 th week.Additionally,novel stent can be implanted into the esophagus successfully.Conclusion 1.Benign esophageal stricture could be established successfully with two balloon catheters.2.The novel biodegradable esophageal stent has advantages,such as good early mechanical properties,degradability and safety.After further optimization,it can provide a more favorable choice for the treatment of esophageal stricture in children.