Functional and tonometrical investigation of bladder and urethra in patients with stress incontinence

Hydrodynamics of micturition following Marshall-Marchetti-Krantz procedure for stress urinary incontinence

Nineteen stress-incontinent females have passed a urodynamic study before and six months after Marshall-Marchetti-Krantz (M-M-K) surgical procedure. It is concluded that postoperative changes in the urethral pressure profile are very limited. However, urethral closure pressure was elevated and functional length shortened, both probably statistically significantly. Synchronous pressure-flow studies pre- and post-operatively showed only slightly and not statistically significantly decreased peak-flow values for three different micturition volumes at detrusor micturitions. At straining micturitions peak-flow was significantly reduced. For small micturition volumes (200 ml) detrusor pressure at peak-flow and at maximum detrusor contraction was significantly elevated after surgery. Urethral resistance was significantly increased for 200 ml and 400 ml micturitions postoperatively, but at micturition with maximum bladder capacity no changes were found. If micturitions are made as detrusor micturitions without strain and with an adequate filling of the bladder, the changes found postoperatively hardly bear clinical significance. Micturitions with heavy straining postoperatively, however, give a reduced flow and increased residual urine to the extent that micturitions in this way should be avoided.

Urodynamics of female urinary incontinence with emphasis on stress incontinence

More than 500 female patients with urinary incontinence were studied in our urodynamic laboratory by simultaneous recordings of urethral pressure at 2 levels, bladder pressure, intra-abdominal pressure, and by uroflowmetry and cine-fluoroscopy. Urethral pressure profile under basal conditions was compared to that in patients with a full bladder, under the stress of sharp or sustained increase in intra-abdominal pressure, voluntary perineal muscle activity and patient's position. From these studies stress and urge incontinence, and neurogenic varieties (or a combination of several types) could be differentiated. The clinical application of our findings will be discussed.

The effect of changes of posture on the urethral closure pressure in healthy women

The effect of changes of posture on hydrodynamic parameters considered important for the maintenance of urinary continence was investigated in 14 healthy women. The subjects were investigated in the supine and erect positions using a previously described technique for simultaneous urethrocystometry, including recording of the urethral pressure profile. It was found that a change from the supine to the standing position increased the maximum intravesical pressure from a mean value of 13 mmHg to 22 mmHg. There was a simultaneous increase in the maximum intra-urethral pressure from a mean of 66 mmHg to 82 mmHg. As a consequence, the urethral closure pressure increased from a mean of 53 mmHg to 60 mmHg. The functional length of the urethra increased from 25 mm to 28 mm, and the absolute length from 28 mm to 36 mm. It is concluded that in healthy women, a change from the supine to the standing position causes a rise in the maximum intra-urethral pressure and an increase in the absolute and functional lengths of the urethra. These effects counteract the simultaneous increase in bladder pressure, and can be regarded as compensatory mechanisms for the maintenance of continence.