Physiological and Pathological Urethral Pressure Variations

Abstract

From an analysis of 202 patients and a careful literature analysis we conclude that pathological urethral instability should be differentiated from physiological urethral pressure variations by the following criteria: a pronounced amplitude of at least one third of the maximum urethral pressure variations by the following criteria: a pronounced amplitude of at least one third of the maximum urethral closure pressure (usually > 25 cm H₂O), a short duration (1–5 s), a simultaneous inhibition of the electromyographic activity in urethral and (or) anal sphincter, and the occurrence of the phenomena starting at the beginning of bladder filling (100 ml).

Urethral Instability: Current Pathophysiological Concept

“…In our opinion, FSF is often derived from observed urethral pressure changes. In accordance with the criteria of Vereecken [22] , we find an early pathological FSF in the majority of patients with URI. A drop in urethral pressure is often present at the FSF.…”

“…Pathological urethral pressure variations should be distinguished from physiological urethral pressure variations according to Vereecken [22] . The focus should be on the following criteria: amplitude, duration, sphincteric EMG, repetition throughout the filling phase and loss of urine.…”

Additional value of triple‐sensor urethral catheter in demonstrating urethral pressure variations during filling cystometry

“…In the literature, a diversity of cut‐off values and categories have been used to describe UPV. Definitions have been used with a fixed cut‐off value between 10 to 30 cmH2O, dependent on the pattern, peak‐to‐peak time and as percentage or difference with maximum urethral pressure . While the air balloon measurements have less variability than other measurement types, there are no normal ranges for the technology used, maybe varying pressure amounts may need to be adjusted for which type of sensor is used, although no significant differences between the two measurements in the same patient occurred in this series.…”

Continuous urethral pressure measurements; measurement techniques; pressure variations; clinical interpretations; and clinical relevance. A Systematic Literature Analysis

“…OAB is urodynamically associated with both the presence and absence of detrusor overactivity (DO). Urethral pressure variations (UPV) are observable with continuous intra urethral pressure measurement and have been observed during urodynamic investigation as well in association with DO in patients with lower urinary tract symptoms (LUTS) as in individuals without LUTS . The clinical relevance of UPV, also referred to as urethral instability, in the pathophysiology of OAB has remained controversial since the initial reports .…”

“…In the period 1978-1996 various studies have described UPV and discussed whether this is an isolated entity separate from DO or not, without an unambiguous conclusion. 5,[8][9][10][11][12] The International Continence Society (ICS) defined unstable urethra in 1981 as the condition where urinary loss is solely caused by a fall in urethral pressure. 13 The condition defined by this definition is however rare and as a consequence various propositions for a definition have been made.…”