Hydrodynamics of micturition in stress-incontinent women. Comparisons of pressure and flow at different micturition volumes in stress-incontinent and continent women.

The urethral flow, resistance and closure pressure and bladder pressures in 19 stress-incontinent but otherwise healthy women were compared with the same parameters in 19 healthy, continent women. The micturition studies were performed at three predetermined levels of bladder filling. The urethral closure pressure, the premicturition intravesical pressure and detrusor pressure at micturition were significantly lower in the stress-incontinent women than in the continent group. The intravesical opening pressure showed no intergroup difference. The urethral and bladder pressure measurements in the incontinent women indicated musculo-elastic tissue with greater compliance and less contractility than in normal women.