Urethral bulking injections
A urethral bulking injection is a gynecological procedure and medical treatment used to treat involuntary leakage of urine: urinary incontinence in women. Injectional materials are used to control stress incontinence. Bulking agents are injected into the mucosa surrounding the bladder neck and proximal urethra. This reduces the diameter of the urethra and creates resistance to urine leakage. After the procedure, the pressure forcing the urine from the bladder through the urethra is resisted by the addition of the bulking agent in the tissue surrounding the proximal urethra. Most of the time this procedure prevents urinary stress incontinence in women.
Uses
A urethral bulking injection is one type of treatment for incontinence in women. Urethral bulking injections are considered by a clinician when the woman has urinary sphincter dysfunction, urethral hypermobility, persistent stress urinary incontinence after a urethral sling or urethropexy, or stress urinary incontinence in women who cannot undergo surgery due to other illnesses or conditions. It restores the ability to retain urine during coughing, laughing and other normal occurrences that increase inter-abdominal pressure Some women choose to have urethral bulking injections because they wish to avoid surgery or the use of mesh material. Another reason other treatments may not be chosen include the desire to maintain fertility. Woman who benefit most from this treatment are those who have a stable bladder neck and an inadequate muscle strength of the sphincter muscles that close the urethra. Urethral instability is identified by the angle of the urethra. This can be evaluated when the woman lies on her back and the angle of the urethral is greater than 30° during coughing. Tests are performed to confirm the diagnosis of stress urinary incontinence such as the bladder capacity to hold urine and the strength of the bladder muscle contractions.Diagnosis is aided before the procedure by a thorough evaluation of the woman. Information that is gathered prior to the injection includes consists of a medical history and physical exam. The residual, postvoid residual urine determination and urinalysis and urine culture help in the diagnosis. The surgeon will ask the woman to keep a diary of urine output and frequency. The physician may order a urodynamic evaluation to establish the diagnosis of intrinsic sphincter deficiency. A voiding diary and/or a measured voided volume gives an estimate of bladder capacity. A free-flow uroflowmetric examination gives additional information about flow rate, voided time and volume. A cystometrogram will evaluate detrusor over-activity, bladder compliance, bladder capacity, and abdominal leak pressure. Another diagnostic tool is the urethral pressure profile. This measures the maximum urethral closure strength. The physician will use instrumentation and do a visual examination called a urethroscopic visualization.
Contraindications
A woman may not be a good candidate for the procedure. Contraindications for this treatment are having a current urinary tract infection, having difficulty emptying the bladder, having a urethral stricture, having a urethral obstruction or having fragile or sensitive tissue where the injections are to be placed. In some women, cancer treatments may have created changes in the urethra, bladder and sphincter muscles which would prevent the success of the treatment.Available bulking agents
- Durasphere
- Macroplastique
- Coaptite