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Updated: Mar 25, 2026

Detrusor Underactivity Model in Rats by Conus Medullaris Transection
Published on: August 28, 2020
Fundamentals and clinical perspective of urethral sphincter instability as a contributing factor in patients with
Ruth Kirschner-Hermanns1, Ralf Anding1, Peter Rosier2
1Neuro-Urologie, University Clinic Friedrich-Wilhelms-University Bonn and Neurologic Rehabilitation Center Godeshoehe, Germany.
Aims:
Urethral pathophysiology is often neglected in discussions of bladder dysfunction. It has been debated whether "urethral sphincter instability," referred to based on observed "urethral pressure variations," is an important aspect of overactive bladder syndrome (OAB). The purpose of this report is to summarize current urethral pathophysiology evidence and outline directions for future research based on a literature review and discussions during the ICI-RS meeting in Bristol in 2014.
Methods:
Urethral pathophysiology with a focus on urethral pressure variation (UPV) was presented and discussed in a multidisciplinary think tank session at the ICI_R meeting in Bristol 2014. This think tank session was based on collaboration between physicians and basic science researchers.
Results:
Experimental animal studies or studies performed in clinical series (predominantly symptomatic women) provided insights into UPV, but the findings were inconsistent and incomplete. However, UPV is certainly associated with lower urinary tract symptoms (likely OAB), and thus, future research on this topic is relevant.
Conclusions:
Future research based on adequately defined clinical (and urodynamic) parameters with precisely defined patient groups might shed better light on the cause of OAB symptoms. Further fundamental investigation of urethral epithelial-neural interactions via the release of mediators should enhance our knowledge and improve the management of patients with OAB.
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