Portilla E, Ramos A, Ramos L, de Buen N, García D, Rodríguez-Reynoso S, Larios F, Terán C
Surgical Research Division, Centro de Investigación Biomédica de Occidente Instituto Mexicano del Seguro Social, Guadalajara, Jal., Mexico.
J Invest Surg. 1999 Jul-Aug;12(4):205-11. doi: 10.1080/089419399272476.
The characteristics of a model of urolithiasis in the bladder of male Wistar rats were evaluated. Two techniques were compared: one knot of suture material through the bladder wall, or 15-throw knots inside the bladder. Rats were randomly assigned to one of six groups, according to the technique and suture material used (polyester, silk, or chromic catgut). An excretory urogram was performed at days 30, 60, and 90. At the moment of positive radiographic diagnosis, animals were sacrificed and stones were obtained. All rats were sacrificed at day 90 regardless of the x-ray results. Variables evaluated were average days to a positive urogram, average weight of all uroliths, and percentage of animals developing urolithiasis throughout the study. There were no statistical differences between groups for the average weight of stones, which ranged from 0.008 to 1.502 g for individual cases. All three materials were more lithogenic with the 15-throw knot inside technique. No significant differences were detected for lithogenesis criteria between suture materials. X-ray dispersion spectroscopy evidenced calcium phosphate composition of two stones from chromic catgut, and magnesium phosphate composition of two stones from chromic catgut, two from silk, and two from polyester. Neo-epithelization over the suture was confirmed microscopically in bladders with the one-throw technique. We conclude that (1) this is an effective model of urolithiasis, with predictability in time, composition, and amount of stone formation; (2) the presence of more suture material inside the bladder is more lithogenic; and (3) excretory urograms are highly sensitive and specific for the noninvasive diagnosis of bladder urolithiasis.
对雄性Wistar大鼠膀胱结石模型的特征进行了评估。比较了两种技术：一种是通过膀胱壁缝合材料打结，另一种是在膀胱内打15个结。根据所使用的技术和缝合材料（聚酯、丝线或铬制肠线），将大鼠随机分为六组之一。在第30、60和90天进行排泄性尿路造影。在放射学诊断呈阳性时，处死动物并获取结石。无论X射线结果如何，所有大鼠均在第90天处死。评估的变量包括排泄性尿路造影呈阳性的平均天数、所有尿路结石的平均重量以及在整个研究过程中发生尿路结石的动物百分比。各组结石的平均重量无统计学差异，个别病例的结石重量范围为0.008至1.502 g。采用在膀胱内打15个结的技术时，所有三种材料都更易形成结石。不同缝合材料之间在结石形成标准方面未检测到显著差异。X射线色散光谱法证明，铬制肠线的两块结石为磷酸钙成分，铬制肠线的两块、丝线的两块和聚酯的两块结石为磷酸镁成分。采用单结技术的膀胱在显微镜下证实了缝线处有新上皮形成。我们得出以下结论：（1）这是一种有效的尿路结石模型，在结石形成的时间、成分和数量方面具有可预测性；（2）膀胱内存在更多的缝合材料更易形成结石；（3）排泄性尿路造影对膀胱结石的无创诊断具有高度敏感性和特异性。
