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Updated: Aug 18, 2026

Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse
Published on: April 17, 2019
[Physiology of the anal and urinary sphincter apparatus for continence]
Anne-Marie Leroi1, Loïc Le Normand
1Pavillon Derocque, Hôpital Charles Nicolle, Rouen, France.
Abstract:
This report of the 27th congress of the Société Internationale Francophone d'Urodynamique (SIFUD) describes the mechanisms which allow the anal and urethral sphincter apparatus to ensure faecal and urinary continence. It successively described sphincter anatomy, the structure and ultrastructure of its muscle components, its innervation, neurotransmission and functioning regimens at rest, on effort and on straining. This study illustrates the differences but also the similarities of functioning of these two sphincter apparatuses. This can explain the high frequency of associated urinary and anal incontinence.
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