Utilization of 3D-printed polymer stents for benign esophageal strictures in patients with caustic ingestion

Abstract

Aim: This study aimed to introduce a 3D printed, flexible esophageal stent, which is useful in personalized treatment of patients with esophageal strictures and also reduce the adverse effects of the existing esophageal stent. Materials & methods: Bio-grade polylactic acid (PLA), bio-grade transparent thermoplastic polyurethane and bio-grade polyvinyl alcohol (PVA) granules were purchased. The dichloromethane (DCM) and dimethylformamide (DMF), and the double distilled water were used as the solvent for PLA, thermoplastic polyurethane and PVA, respectively. The stent was designed by Solidworks software and subsequently printed by a 3D bioprinter (Mobio Tech V1.2). The biocompatibility, self-expansion, anti-inflammation and cytotoxicity of the printed stent were assessed in an in vitro and in vivo normal canine esophagus. An individualized 3D-printed flexible polymer stent was also implemented for a 16-year-old boy who presented with esophageal stricture following ingestion of corrosive chemicals. The patient was followed for 2 months with further endoscopic and pathology evaluations. Results: Several tests were performed before and after the stent placement. Mechanical tests showed that the nature and behavior of the polymeric materials used in the esophagus stent did not change significantly along treatment. Pathology results further indicated that the polymer stent did not have major inflammatory effects and cytotoxicity. Conclusion: The results show that the individualized 3D printed Biocompatible polymeric stent has potential applications in treating esophageal strictures.