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Magnetically Controlled Endourethral Artificial Urinary Sphincter


Urinary incontinence is a largely spread disfunction that affects more than 300 million people worldwide. At present, no technological solutions are able to restore continence in a minimally invasive and effective way. In this article the authors report the design, fabrication, and testing of a novel artificial endourethral urinary sphincter able to fully restore continence. The device can be inserted/retracted in a minimally invasive fashion without hospital admission, does not alter the body scheme and can be applied to both women and men. The device core is a unidirectional polymeric valve and a magnetically activated system able to modulate its opening pressure. Bench tests and ex vivo tests on a human cadaver demonstrated that the device is able to fully restore continence and to allow urination when desired. Overall, the proposed system shows a high potential as a technological solution able to restore a normal daily life in patients affected by urinary incontinence.

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The authors acknowledge the Fondazione Cassa di Risparmio di Lucca (Lucca, Italy) for providing financial support for this study, in the framework of the SUAVES (Artificial urinary system based on bladder and sphincter endoprostheses) and the VESPRO (Protesi di VEscica e Sfintere per il riPristino funzionale dell’apparato uRinariO) projects.

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Correspondence to Leonardo Ricotti.

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Associate Editor Umberto Morbiducci oversaw the review of this article.

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Supplementary Video S1 (MP4 13797 kb)

Supplementary Video S2 (MP4 9303 kb)

Supplementary Video S3 (MP4 10986 kb)

Supplementary Video S4 (MP4 9094 kb)

Supplementary Video S5 (MP4 47361 kb)

Supplementary material 6 (PDF 2707 kb)

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Mazzocchi, T., Ricotti, L., Pinzi, N. et al. Magnetically Controlled Endourethral Artificial Urinary Sphincter. Ann Biomed Eng 45, 1181–1193 (2017).

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  • Urinary incontinence
  • Artificial sphincter
  • Magnetic device
  • Minimally invasive therapy
  • Unidirectional valve