Preparation and experimental evaluation of degradable esophageal stents based on novel polylactic acid materials

Esophageal stricture is a common esophageal disorder in both adults and children. The current standard clinical treatment is endoscopic dilation, which suffers from high recurrence rate and the need for repeated dilation. Although metallic esophageal stents can provide long-term support, they tend to cause complications such as migration, perforation, and bleeding, and require a second surgery for removal. Biodegradable stents are regarded as an ideal alternative because they can maintain esophageal patency and degrade spontaneously. To overcome the limitations of existing stents, this study used L-lactide and ε-caprolactone as main raw materials to prepare crosslinked polymers via ring-opening copolymerization and crosslinking reaction, and incorporated a contrast agent to construct a composite material with both imaging function and biodegradable properties. The material structure was characterized by Fourier-transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and gel permeation chromatography. Furthermore, an anti-migration stent structure was designed and fabricated into a solid stent by compression molding. In vitro mechanical performance tests and degradation experiments demonstrated that the prepared stent exhibits favorable mechanical properties and controllable degradability, showing potential application value in the treatment of benign and malignant esophageal strictures.