The Stone Centre, Vancouver General Hospital, Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
J Urol. 2013 Feb;189(2):719-25. doi: 10.1016/j.juro.2012.08.202. Epub 2012 Oct 8.
Ureteral stents are prone to irritation, encrustation and infection, and they require additional procedures for removal. Furthermore, indwelling polymer stents are often forgotten with devastating consequences to the patient. We describe the degradation time, and physiological and histological responses elicited by a novel biodegradable ureteral stent in a porcine model.
A total of 16 female Yorkshire pigs were used in the study. Ten biodegradable Uriprene™ stents and 6 biostable Polaris™ stents were cystoscopically inserted unilaterally in 2 groups of animals. Excretory urogram, and blood and urine tests were performed on different days until day 28. Biostable stents were removed on day 21. On day 28 all pigs underwent necropsy for microscopic and histological evaluation.
Nine of the 10 biodegradable stents (90%) degraded completely by 4 weeks, while 1 pig had 3 fragments smaller than 1.5 cm in the bladder. Excretory urogram showed equivalent drainage and significantly less hydronephrosis in biodegradable stented kidneys. Blood and urine parameters were similar in the 2 groups. A transient increase in serum creatinine on day 7 in 40% of the pigs with a degradable stent resolved by day 10. There were significantly fewer abnormal histological findings in the degradable stent group. We evaluated drainage characteristics in an unobstructed ureter and results may not be representative of what develops in obstructed ureters.
The third generation biodegradable stent is a safe, effective alternative to conventional polymer stents, resulting in equivalent drainage and less hydronephrosis.
输尿管支架易受刺激、结垢和感染，需要额外的取出程序。此外，留置聚合物支架经常被遗忘，给患者带来灾难性后果。我们描述了一种新型可生物降解输尿管支架在猪模型中的降解时间、生理和组织学反应。
本研究共使用了 16 头雌性约克夏猪。10 个可生物降解的 Uriprene™支架和 6 个生物稳定的 Polaris™支架在两组动物中分别通过膀胱镜插入单侧。在不同的日子进行排泄性尿路造影术以及血液和尿液检查，直到第 28 天。生物稳定的支架在第 21 天取出。在第 28 天，所有猪都进行了尸检，以进行显微镜和组织学评估。
10 个可生物降解支架中的 9 个（90%）在 4 周内完全降解，而 1 只猪的膀胱中有 3 个小于 1.5 厘米的碎片。排泄性尿路造影显示可生物降解支架的肾脏引流和肾积水明显减少。两组的血液和尿液参数相似。在 40%的可生物降解支架组中，有 7 天的血清肌酐短暂升高，到第 10 天恢复正常。可生物降解支架组的异常组织学发现明显减少。我们评估了未阻塞输尿管的引流特征，结果可能不能代表阻塞输尿管的发展情况。
第三代可生物降解支架是传统聚合物支架的安全、有效替代品，可实现等效引流和减少肾积水。
