Park Jung-Hoon, Song Ho-Young, Shin Ji Hoon, Kim Jin Hyoung, Jun Eun Jung, Cho Young Chul, Kim Soo Hwan, Park Jihong
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap 2-dong, Songpa-gu, Seoul 138-736, Republic of Korea.
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Poongnap 2-dong, Songpa-gu, Seoul 138-736, Republic of Korea.
J Vasc Interv Radiol. 2014 Aug;25(8):1257-1264.e1. doi: 10.1016/j.jvir.2014.03.023. Epub 2014 Jun 7.
To investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model.
PDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction.
Stent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P < .001), the average thickness of papillary projection (0.80 mm vs 1.28 mm; P < .001), and the average thickness of submucosal fibrosis (0.34 mm vs 0.49 mm ; P < .001) were significantly increased in group B versus group A. There were no significant differences between group B and group C. The average inflammatory cell infiltration did not differ significantly in the three groups. Molecular weight losses were 54% in group A and 84% in group B. In group C, PDO stents were completely decomposed.
An experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks.
在犬尿道模型中植入聚对二氧环己酮（PDO）可生物降解支架后，研究其炎症反应并对生物降解进行定量分析。
将PDO可生物降解支架植入9只雄性杂种犬的尿道近端和远端。在支架植入后4周（A组；n = 3）、8周（B组；n = 3）或12周（C组；n = 3）对犬实施安乐死。通过随访逆行尿道造影评估植入支架的尿道腔直径，并在犬处死后获取组织学结果。安乐死后取出支架，评估其表面形态和分子量。进行血液学检查以评估炎症反应。
所有犬的支架植入技术均成功。平均腔直径逐渐减小。与A组相比，B组的平均上皮层数（2.93对4.42；P <.001）、乳头突起平均厚度（0.80 mm对1.28 mm；P <.001）和黏膜下纤维化平均厚度（0.34 mm对0.49 mm；P <.001）均显著增加。B组和C组之间无显著差异。三组的平均炎症细胞浸润无显著差异。A组的分子量损失为54%，B组为84%。在C组中，PDO支架完全分解。
犬尿道模型的实验研究表明，在12周内炎症反应可接受，肉芽组织逐渐增加，但无管腔阻塞。
