Bacterial cellulose to reinforce urethrovesical anastomosis. A translational study

Abstract Purpose: To evaluate the efficacy of the cellulosic exopolysaccharide membrane (CEM) as a urethral reinforcement for urethrovesical anastomosis. Methods: Twenty eight rabbits were submitted to urethrovesical anastomosis with or without CEM reinforcement. The animals were divided into 4 groups: C7, CEM7, C14 and CEM14: (C= only anastomosis or CEM = anastomosis + CEM), evaluated after 7 weeks, and 14 weeks. The biointegration and biocompatibility of CEM were evaluated according to stenosis, fistula, urethral wall thickness, urethral epithelium, rate of inflammation and vascularization. Results: Between the two experimental groups, the difference in the number of stenosis or urinary fistula was not statistically significant. The morphometric analysis revealed preservation of urethral lumen, well adhered CEM without extrusion, a controlled inflammatory process and implant vascularization. The urothelium height remained constant over time after CEM reinforcement and the membrane wall was thicker, statistically, after 14 weeks. Conclusion: The absence of extrusion, stenosis or urinary fistula after 14 weeks of urethrovesical anastomosis demonstrates cellulosic exopolysaccharide membrane biocompatibility and biointegration with tendency to a thicker wall.

摘要 目的：评估纤维素外多糖膜（cellulosic exopolysaccharide membrane，CEM）作为尿道加固材料应用于尿道膀胱吻合术（urethrovesical anastomosis）的有效性。方法：28只家兔接受尿道膀胱吻合术，术中施加或不施加CEM加固，将实验动物分为4组：C7、CEM7、C14及CEM14组，其中C组仅行尿道膀胱吻合术，CEM组则在吻合术中加用CEM进行尿道加固，分别于术后7周、14周进行评估。本研究通过观察尿道狭窄、瘘管形成、尿道壁厚度、尿道上皮形态、炎症发生率及血管化程度，评估CEM的生物整合性与生物相容性。结果：两组实验动物的狭窄或尿瘘数量差异无统计学意义。形态计量学分析显示，实验组尿道管腔得以保留，CEM贴合良好且无外露，炎症反应可控，植入物可见血管化。经CEM加固后，尿道上皮高度随时间保持稳定；术后14周时，膜壁厚度较此前显著增加，差异具有统计学意义。结论：尿道膀胱吻合术后14周未出现CEM外露、狭窄或尿瘘情况，证实该纤维素外多糖膜具备良好的生物相容性与生物整合性，且膜壁存在增厚趋势。