Institute of Pathology and Parasitology, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic.
J Thorac Cardiovasc Surg. 2012 Feb;143(2):437-44. doi: 10.1016/j.jtcvs.2011.08.002. Epub 2011 Aug 31.
This study was undertaken to evaluate safety and biocompatibility of a novel biodegradable polydioxanone stent in a rabbit tracheal model. Metallic and silicone stents represent standard therapeutic approaches for hollow organ stenosis, although complications have been reported repeatedly. Biodegradable stents could reduce the risks associated with this procedure while still achieving the purpose of maintaining lumen patency.
A commercially available polydioxanone suture strand with a long safety record was used to manufacture the self-expanding stents. The polydioxanone stents were then implanted bronchoscopically and under fluoroscopic guidance into the tracheas of white rabbits (N = 25). Periodic clinical examination was performed. Histopathologic examination concluded the study for the 5 experimental groups at 3, 4, 5, 10, and 15 weeks after implantation.
There were no unexpected deaths and no stent displacements during the study. The animals remained in good condition, without stent debris expectoration. Macroscopic examination revealed that the tracheal lumen stayed open. Histologic examination showed that tracheal damage score was highest 5 weeks after stenting, including in-stent necrosis of the epithelium. Stent degradation was complete with no remnants after 10 weeks, leaving the trachea completely healed at 15 weeks after implantation.
This animal airway model has demonstrated acceptable safety and biocompatibility of this novel biodegradable polydioxanone stent. We suggest that polydioxanone stenting be used for further clinical studies for cases in which complete stent degradation after temporary airway treatment is desirable.
本研究旨在评估一种新型可生物降解聚二氧六环酮支架在兔气管模型中的安全性和生物相容性。金属和硅胶支架是治疗中空器官狭窄的标准治疗方法，但已反复报道其并发症。可生物降解支架可降低与该手术相关的风险，同时仍能达到保持管腔通畅的目的。
使用具有长期安全记录的市售聚二氧六环酮缝线制造自膨式支架。然后，将聚二氧六环酮支架经支气管镜和透视引导植入白兔（N=25）的气管中。定期进行临床检查。组织病理学检查在植入后 3、4、5、10 和 15 周结束了 5 个实验组的研究。
研究过程中无意外死亡和支架移位。动物状况良好，无支架碎片咳出。肉眼检查显示气管腔保持通畅。组织学检查显示，支架植入后 5 周时气管损伤评分最高，包括支架内上皮坏死。10 周后支架完全降解，无残留，植入 15 周后气管完全愈合。
这种动物气道模型已经证明了这种新型可生物降解聚二氧六环酮支架具有可接受的安全性和生物相容性。我们建议在需要临时气道治疗后完全降解支架的情况下，将聚二氧六环酮支架用于进一步的临床研究。
