The Impact of Bladder Neck Suspension on the Resting and Stress Urethral Pressure Profile: A Prospective Study Comparing Controls with Incontinent Patients Preoperatively and Postoperatively

Abstract

For further understanding of the urodynamics of urinary stress incontinence 20 female patients with this condition were evaluated using resting and stress urethral pressure profiles before and after endoscopic suspension of the bladder neck. The results were compared to those in 13 normal volunteers who were evaluated similarly. In addition, the effect of posture on the urethral pressure profile was studied with the patients in the supine, standing and sitting positions. The results show that the mean maximum urethral closure pressure and functional profile length were significantly lower (p equals 0.005) in patients with stress urinary incontinence when compared to the normal volunteers. Posture did not significantly affect the maximum urethral closure pressure and functional profile length in either group (p greater than 0.1). Successful endoscopic suspension of the bladder neck did not significantly alter the maximum urethral closure pressure, while it significantly increased the functional profile length with the patient in the standing position only (p less than 0.05). The stress urethral pressure profile separated objectively the stress urinary incontinent patients and the continent volunteers. In continent women the transmitted abdominal pressure in the urethra during a cough or Valsalva’s maneuver was significantly higher than that in the bladder over most of the urethral length in all 3 positions. In the group with stress urinary incontinence the transmitted abdominal pressure in the urethra during the same maneuvers was less than that in the bladder. The data also showed that the stress urethral pressure profile curves in patients with stress urinary incontinence who were cured surgically reverted to the normal control pattern with higher abdominal pressure transmission in the urethra than in the bladder during a cough or Valsalva’s maneuver.The anatomical and physiological implications of these findings with their clinical application in the understanding of the mechanisms of continence in normal and stress incontinent women are discussed.