Department of Radiology, University of Bonn , Bonn, Germany .
J Endourol. 2014 Jun;28(6):708-16. doi: 10.1089/end.2014.0088. Epub 2014 Mar 24.
To evaluate the occlusive properties of latex-covered Amplatzer Vascular Plugs (AVPs) for transrenal ureteral occlusion in vitro.
Latex-covered AVPs type I and II (diameter 8, 10, 12, 14, and 16 mm) were used as occlusive devices. Radial force of an AVP was measured using simulated ureteral diameters of 4 to 12 mm. Occlusive properties were examined in a silicone tube (inner diameter 6 mm) with measurement of drainage time of a 40 cm water column. In complete occlusion, the maximum pressure that the plug was able to withstand was determined at different temperature levels. Statistical analysis of drainage time was performed in a general linear model (GLM) and using correlation analyses. Explanted porcine ureters were used to simulate physiologic conditions. Pressure measurements were performed until leakage, plug dislocation, or rupture of the ureter occurred.
Radial force depended on AVP type, size, ureteral diameter, and temperature. The 16-mm AVP II showed the highest radial force of more than 5 N (ureteral diameter 4 mm, body temperature). All AVP I showed water leakage and plug dislocation. Drainage time of the AVP II depended significantly on plug size and temperature and correlated with radial force (r=0.731, P<0.001). In complete occlusion, water leakage occurred at 500 to 1000 cm H2O and dislocation between 500 to more than 2000 cm H2O. In porcine ureters, leakage occurred at room temperature between 19 to 93 cm H2O. At body temperature, all AVP II occluded the ureter completely.
Latex-covered AVP II (diameter 8-16 mm) can effectively occlude the ureter, especially considering remodeling of the nitinol at body temperature. Large plug diameters can exert enough radial force even in dilated ureters to allow for successful occlusion. Because deployment of a 16-mm latex-covered AVP II can be technically difficult, we advocate the use of 12- or 14-mm AVP II for transrenal ureteral occlusion. AVP Is are not suitable for ureteral occlusion.
评估经肾输尿管乳胶包裹 Amplatzer 血管塞（AVP）在体外用于经肾输尿管闭塞的闭塞性能。
使用乳胶包裹的 I 型和 II 型 AVP（直径 8、10、12、14 和 16mm）作为闭塞装置。使用模拟的 4 至 12mm 输尿管直径测量 AVP 的径向力。在硅胶管（内径 6mm）中检查闭塞性能，测量 40cm 水柱的排水时间。在完全闭塞的情况下，在不同温度水平下确定塞子能够承受的最大压力。使用一般线性模型（GLM）和相关分析对排水时间进行统计分析。使用猪输尿管进行离体实验以模拟生理条件。进行压力测量，直至发生泄漏、塞子移位或输尿管破裂。
径向力取决于 AVP 类型、大小、输尿管直径和温度。16mm 的 II 型 AVP 表现出超过 5N 的最高径向力（输尿管直径 4mm，体温）。所有 I 型 AVP 均出现漏水和塞子移位。II 型 AVP 的排水时间显著取决于塞子大小和温度，并与径向力相关（r=0.731，P<0.001）。在完全闭塞的情况下，水泄漏发生在 500 至 1000cmH2O，而在 500 至超过 2000cmH2O 之间发生塞子移位。在猪输尿管中，室温下泄漏发生在 19 至 93cmH2O。在体温下，所有的 II 型 AVP 均完全闭塞了输尿管。
乳胶包裹的 AVP II（直径 8-16mm）可有效闭塞输尿管，尤其是考虑到在体温下镍钛合金的重塑。即使在扩张的输尿管中，大直径的塞子也可以产生足够的径向力，从而实现成功闭塞。由于 16mm 乳胶包裹的 AVP II 的部署可能具有技术难度，因此我们主张使用 12 或 14mm 的 AVP II 进行经肾输尿管闭塞。AVP I 不适合用于输尿管闭塞。
