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Updated: Oct 6, 2025

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing
Published on: August 14, 2019
Urethral pressure profile during ejaculation in men with spinal cord injury
Jean-Gabriel Previnaire1, Jean-Marc Soler2, Melody Plets3
1Spinal Unit, Centre Calve, Fondation Hopale, Berck-sur-Mer, France. jean.previnaire@fondation-hopale.org.
Abstract:
Ejaculation is often impaired in men with spinal cord injury (SCI). The aim of this prospective study was to assess sequence of sphincteric events and ejaculation dyssynergia during penile vibratory stimulation (PVS) in SCI men. Simultaneous recordings of bladder, bladder neck, prostate and external urethral sphincter pressures were performed using a microtip catheter with 5 pressure transducers. Between 2017 and 2019, ten men participated in the study for a total of 17 procedures. Antegrade ejaculation was found in three men with upper motor neuron (UMN) lesion. Ejaculation was preceded by a progressive increase in all urethral pressures, reaching sustained (plateau) or intermittent peaks above 220 cm H20. Antegrade ejaculation occurred after intermittent decreases in pressure at the external urethral sphincter level down to 100 cm H20, while the pressure at the bladder neck remained high (up to or above 220 cm H20). PVS was ineffective in eliciting ejaculation in seven men. In the five patients with UMN lesions, PVS elicited an increase in the external urethral sphincter pressure (mean 51 cm H20), while there was no pressure change in the two patients with lower motor neuron lesions. Due to lack of enough retrograde retrieval attempts, the hypothesis of ejaculatory dyssynergia could not be verified.
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