1. Persistent (early, never experienced dryness) SUI
2. Recurrent (initial success and then failure) SUI
3. Patient desires additional treatment
4. Persistent deNovo urge
5. Development of a fistula
Another option is that the SUI is treated successfully, but there is a complication which can be manifested as a mesh complication or difficulty with voiding/obstruction.
SSI surgical failure can be defined in a more flexible manner, using the surgeons/patient’s assessment of cure on the last follow-up visit, or using the strict definition which includes an objective and subjective component of assessment at a minimum follow-up of 12 months.
According to the American Urologic Association (AUA) guidelines, mid urethral slings (MUS) with the insertion of a mesh, have comparable efficacy to autologous slings (pubovaginal or fascial slings). Usage of MUS entails more rapid recovery and more efficient return to normal voiding. The rare complication of mesh extrusion should be avoided by using intraoperative cystoscopy to examine the bladder and urethra and minimize the risk of urinary tract injury.
Not all the slings are the same, and not all MUS is the same. They all differ in their treatment success rates and complications rates. Contemporary data demonstrate that MUS is the mainstay first line treatment for SUI. MUS can perform either as a retropubic MUS (RMUS) or as a transobturator (TMUS) approach. RMUS has 13.8% failure rate after a follow-up of 94 months. The TMUS has a failure rate of 31-36% at 10 years follow-up.
In The Stress Incontinence Surgical Treatment Efficacy Trial (SISTEr)1, Burch colposuspension (Burch colposuspension (a procedure used to treat urinary incontinence due to pelvic floor relaxation. It entails the attachment of the paravaginal fascia to Cooper's ligament), and autologous rectus fascial sling were analyzed. Between 34-51% of the patients had failed. In the 5-Year Longitudinal Follow-up after Retropubic and Transobturator Midurethral Slings (ToMUS) study2 the failure rate was 20-44%. However, only 48 patients from both trials were retreated.
The risk factors for MUS failure include BMI >25, mixed incontinence, prior SUI surgery, intrinsic sphincter deficiency (ISD), and diabetes.3 Importantly, to evaluate these women:
- A complete history needs to be taken - physicians need to understand the onset of SUI, severity, and characterization of symptoms
- All historical records need to be reviewed
- Complete physical examination needs to be performed - urethral mobility should be assessed; a stress test should be performed, while other vaginal pathology should be assessed. Scars should be noted, and pain, tenderness or numbness associated with a previous sling should be assessed
- Urinalysis and culture need to be done0
- Post-void residual test
- Cystoscopy - performed to discover prior mesh in the urethra and bladder
- Urodynamic studies - Should be able to demonstrate the incontinence, mobility and ISD, assess compliance/ capacity of the bladder, and inform us if there is a potential obstruction
It is most important that urologists determine the reason for failure: whether the wrong procedure was performed, wrong material (mesh) used, lacking technical surgical skills, some change that had occurred in the patents; and other miscellaneous reasons. The treatment consists of several options:
- Conservative – wait and see approach, usage of various medications
- Tightening of a prior sling – for pubovaginal sling this can be done up to 12 weeks following the initially failed procedure. For MUS – it is possible to plicate the mesh with a non-absorbable suture, resulting in cure in 47% of cases
- A repeat MUS procedure – whether retropubic or obturator. Some data suggest that a retropubic approach may be superior to an obturator approach in redo procedures. A good candidate is a patient with healthy vaginal mucosa, and a mobile bladder neck and urethra. In a meta-analysis assessing the outcomes of MUS following MUS, the cure rate was 73.3%5. The question of what to do after a second failed MUS remains unanswered.
- Fascial (Pubovaginal) sling procedure
- Injectable sling –bulking agent
What will determine what kind of procedure the surgeon will perform in patients who have failed initial SUI surgical treatment includes the patient’s expectations, her urethral mobility, urodynamic parameters, whether it is a complex case and the surgeon’s preference? Summing all available evidence, it is clear that we currently have minimal data on how to best treat patients following a failed MUS procedure. What we need are randomized controlled trials between retropubic MUS, transobturator MUS and pubovaginal sling.
In conclusion, failure of primary slings occurs in 12-44% of cases. The known predictors of failure include diabetes, obesity, mixed incontinence, ISD, prior surgery, increased age, and increased pad weight. A complete evaluation of these patients is needed, and randomized controlled trials are needed to provide us with clear answers on how to treat these patients in the best way.
Presented by: E. Ann Gormley, MD, Professor of Surgery in Urology, Dartmouth-Hitchcock Medical Center
References:
1. Tennstedt S et al. Urology 2005
2. Kenton K et al. J Urol 2015
3. Stav et al. Int Urogyn J 2010
4. Kobashi K et al. J Urol 2017
5. Pradhan et al. Int Urogyn 2012
Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, @GoldbergHanan at the 70th Northeastern Section of the American Urological Association (NSAUA) - October 11-13, 2018 - Fairmont Royal York Toronto, ON Canada