From the Department of Radiology and Research Institute of Radiology (K.Y.K., J.H.P., J.T., M.T.K., S.G.K., H.Y.S.), Biomedical Engineering Research Center (J.H.P.), Department of Gastroenterology (Do Hoon Kim), and Department of Pathology (W.C.S.), Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Republic of Korea; and Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Ill (J.H.P., Dong-Hyun Kim).
Radiology. 2018 Jan;286(1):140-148. doi: 10.1148/radiol.2017170414. Epub 2017 Aug 8.
Purpose To investigate the use of sirolimus-eluting biodegradable stents (SEBSs) to suppress granulation tissue formation after stent placement in a rat urethral model. Materials and Methods All experiments were approved by the animal research committee. A total of 36 male Sprague-Dawley rats were randomized into three equal groups after biodegradable stent placement. Group A received control biodegradable stents. Groups B and C received stents coated with 90 µg/cm and 450 µg/cm sirolimus, respectively. Six rats in each group were sacrificed after 4 weeks; the remaining rats were sacrificed after 12 weeks. The therapeutic effectiveness of SEBSs was assessed by comparing the results of retrograde urethrography and histologic examination. Analysis of variance with post hoc comparisons was used to evaluate statistical differences. Results SEBS placement was technically successful in all rats. Urethrographic and histologic examinations revealed significantly less granulation tissue formation at both time points in the rats receiving SEBSs (groups B and C) compared with those that received control stents (group A) (P < .05 for all). There were no significant differences in urethrographic and histologic findings between groups B and C (P > .05 for all). However, the mean number of epithelial layers in group B was higher than that in group C at 4 weeks after stent placement (P < .001). Apoptosis increased in group C compared with groups A and B (P < .05 for all). Conclusion The use of SEBSs suppressed granulation tissue formation secondary to stent placement in a rat urethral model; local therapy with SEBSs may be used to decrease stent-related granulation tissue formation. RSNA, 2017.
目的 研究雷帕霉素洗脱可生物降解支架（SEBS）在抑制大鼠尿道支架放置后肉芽组织形成中的应用。
材料与方法 所有实验均经动物研究委员会批准。在可生物降解支架放置后，36 只雄性 Sprague-Dawley 大鼠随机分为 3 组，每组 12 只。A 组接受对照可生物降解支架。B 组和 C 组分别接受涂有 90μg/cm 和 450μg/cm 西罗莫司的支架。每组各有 6 只大鼠在 4 周后处死；其余大鼠在 12 周后处死。通过逆行尿道造影和组织学检查比较来评估 SEBS 的治疗效果。采用方差分析和事后比较来评估统计学差异。
结果 所有大鼠的 SEBS 放置均技术成功。尿道造影和组织学检查显示，与接受对照支架（A 组）的大鼠相比，接受 SEBS（B 组和 C 组）的大鼠在两个时间点的肉芽组织形成明显减少（所有 P 值均<.05）。B 组和 C 组的尿道造影和组织学结果无显著差异（所有 P 值均>.05）。然而，支架放置 4 周后，B 组的上皮细胞层数平均值高于 C 组（P<.001）。与 A 组和 B 组相比，C 组的细胞凋亡增加（所有 P 值均<.05）。
结论 SEBS 抑制了大鼠尿道支架放置后引起的肉芽组织形成；SEBS 的局部治疗可能用于减少与支架相关的肉芽组织形成。RSNA，2017 年。
