Personalized absorbable gastrointestinal stents for intestinal fistulae and perforations

Gastrointestinal tract;Leakage;Perforation;Obstruction;Stent;Polymer;Polycaprolactone;Polydioxanone;Composite

Fathi, Parinaz ; Pan ; Dipanjan

关键词: Gastrointestinal tract;    Leakage;    Perforation;    Obstruction;    Stent;    Polymer;    Polycaprolactone;    Polydioxanone;    Composite;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/99521/FATHI-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Gastrointestinal (GI) tract perforations and obstructions are relatively frequent surgical emergencies, are potentially life-threatening, and can occur from several different sources. In general, treatment requires urgent surgical repair or resection and at times can lead to further complications. Currently available stents are non-absorbable, are manufactured in a narrow size range, and/or are limited to usage in locations that are accessible for endoscopic removal post-healing. The use of 3D-printed bioresorbable polymeric stents will provide patients with a stent that can prevent leakage, is tailored specifically to their geometry, will degrade with time to eliminate the need for further surgeries for stent removal post-healing, and will be usable in locations that are not endoscopically accessible. This project focused on the characterization of polycaprolactone-polydioxanone (PCL-PDO) composites for use in a bioresorbable gastrointestinal stent. Dynamic Mechanical Analysis (DMA) tests were conducted to separately analyze the effects of composition, the filament formation process, and physiological temperature on the PCL-PDO material properties. The proposed stent design was then modelled using computer-aided design, and Finite Element Analysis (FEA) was used to simulate the effects of physiologically relevant forces on stent integrity. The presence of hydrolysable ester bonds was confirmed using FTIR spectroscopy, and composite morphology was examined with scanning electron microscopy. In vitro studies were used to evaluate the biocompatibility of the polymer composite, finding that the PCL:PDO filament had no negative impact on cell viability over a period of 48 hours, and in fact was conducive to cell proliferation over a period of 3 days. PCL-PDO stents were then 3D-printed and placed in vivo in a pig model, and histological evaluation was used to determine the safety of these stents. Further analyses were conducted through stent placement in ex vivo pig intestines.