Department of Urologic Surgery, University of Minnesota, Minneapolis, Minnesota 55407, USA.
Urology. 2011 Jan;77(1):211-6. doi: 10.1016/j.urology.2010.06.065. Epub 2010 Nov 10.
To assess the functionality, occlusive efficiency, and biocompatibility of a novel artificial urinary sphincter, the tape mechanical occlusive device (TMOD), after implantation in a live canine model, as well as its occlusive efficiency and sizing parameters in human cadavers.
Three female canines underwent implantation of the TMOD at the level of the bladder neck. Functionality was assessed starting at 2 weeks after implantation and continued for ≤9 weeks. The TMODs were activated at 2 weeks and then deactivated for 3, 30-minute sessions daily to permit voiding. The urethral occlusion pressures and biocompatibility for systemic toxicity and the local tissue response were examined. Additionally, the TMOD was inserted in 3 male cadavers to determine the sizing parameters and to assess the urethral occlusion pressures using pressure profilometry.
In the canine model, the urethral occlusion pressures increased from a range of 9-42 cm H(2)O with the TMOD deactivated to a range of 57-82 cm H(2)O with the TMOD activated. Pathologic examination revealed unremarkable pseudocapsular tissues surrounding the device. No histologic or structural evidence of systemic toxicity was observed. Sizing parameters similar to those of other urologic implants were confirmed in the male cadavers, and the urethral occlusion pressures increased from 24 to 30 cm H(2)O with the device deactivated to 61-105 cm H(2)O with the device activated.
The TMOD meets the current standards for an artificial urinary sphincter in terms of functionality, biocompatibility, and achieving desired occlusion pressures following chronic implantation. Additional testing in male canines followed by early human clinical trials is being contemplated.
评估新型人工尿道括约肌——带机械闭塞装置（TMOD）在活体犬模型中的功能、闭塞效率和生物相容性，以及其在人体尸体中的闭塞效率和尺寸参数。
三只雌性犬在膀胱颈部植入 TMOD。在植入后 2 周开始评估功能，并持续进行≤9 周。TMOD 在第 2 周激活，然后每天停用 3 次，每次 30 分钟，以允许排尿。检查了 TMOD 的尿道闭塞压力以及全身毒性和局部组织反应的生物相容性。此外，将 TMOD 插入 3 名男性尸体中，以确定尺寸参数，并使用压力描记法评估尿道闭塞压力。
在犬模型中，TMOD 停用后的尿道闭塞压力范围为 9-42cmH2O，激活后的尿道闭塞压力范围为 57-82cmH2O。病理检查显示设备周围有正常的假性包膜组织。未观察到全身毒性的组织学或结构证据。在男性尸体中确认了与其他泌尿科植入物相似的尺寸参数，并且在设备停用后，尿道闭塞压力从 24 增加到 30cmH2O，在设备激活后增加到 61-105cmH2O。
TMOD 在功能、生物相容性和慢性植入后达到所需的闭塞压力方面符合人工尿道括约肌的当前标准。正在考虑在雄性犬中进行进一步测试，然后进行早期人体临床试验。
