Transurethral Injection of Bulking Agent for the Treatment of Recurrent or Persistent Female Stress Urinary Incontinence after Mid-Urethral Sling


Introduction and Objective

Although mid-urethral sling (MUS) with synthetic materials is associated with high success rates in female stress urinary incontinence (SUI), its widespread use has led to a group of patients with failures, increasing the need for an appropriate salvage procedure. Current options for managing failed MUS are transurethral injection of bulking agent, pubovaginal sling, or repeat MUS. Transurethral injection (TUI) of bulking agent may be appealing in patients in whom was failed the MUS procedure for its minimal invasiveness. In this study we evaluated the efficacy of TUI of bulking agent for the treatment of recurrent or persistent SUI after MUS.

Methods: A retrospective study was conducted involving 23 women who had undergone TUI for recurrent or persistent SUI after MUS. Eight patients had TVT (Gynecare; Ethicon Inc., NJ, USA), 7 had TVT-O (Gynecare), 6 had IRIS-TOT (Dow medics, Korea), and 2 had anterior IVS (Tyco Healthcare, CO, USA). Median interval of MUS and TUI procedure was 12 (3-65) months. Median age was 52 (44-77) at TUI. The distribution of the Stamey Urinary Incontinence Scale (0 = dry; 1 = leakage with vigorous activity; 2 = leakage with minimal stress; and 3 = leakage regardless of activity or position) before TUI were grade I in 11, II in 9, and III in 3 patients. Injection materials were Macroplastique (Uroplasty BV, Geleen, Netherlands) in 21 patients and Durasphere (Boston Scientific, MA, USA) in 2 patients. The injection was given with local anaesthesia under direct cystoscopic guidance. Bulking agents were injected transurethrally into the submucosa using a 20 G needle. Average total volume of material injected was 2.6 (1.5-5.5) cc. The primary outcome measure was subjective cure rate based on the Sandvik questionnaire (1). Subjective cure was defined as “no” experience of SUI in the past 7 days. Subjective symptom visual analogue scale (0=none, 10=unbearable) was used to represent the severity of SUI symptoms experienced by the patient. Other outcome measures included incontinence quality of life (I-QoL), benefit, satisfaction, and willingness to continue (BSW) questionnaire, and flow rate and postvoid residual. Adverse events were also evaluated.

Results: With the median follow-up of 5 (1-34) months, the cure rate was about 35% (8/23). Cure rates according to the baseline Stamey Urinary Incontinence Scale were not significantly different. Subjective symptom visual analogue scale was significantly improved from the average of 8.50 to 1.75 (p = 0.000). Mean total I-QoL scores improved by 24.4 points. Mean avoidance and limiting behaviour (pre: 48.3 vs post: 75.0, p = 0.007), psychosocial impact (pre: 44.7 vs post: 72.5, p = 0.007), and social embarrassment (pre: 37.5 vs post: 67.0, p = 0.008) domain scores improved after TUI. Ninety two percent of the patients stated that they had benefit from the treatment. And 64% of those patients stated they had “much benefit”. Seventy seven percent of the patients were satisfied with the treatment. And 50% of those were “very satisfied”. Overall, all patients stated that they would undergo the procedure again under the same circumstances, and 77% would recommend this treatment to a friend with the same condition. Pre- and post-injective maximum flow rates (14.4 ± 5.4 vs 11.0 ± 6.0 mL/sec, p = 0.162) and postvoid residuals (31.0 ± 50.7 vs. 30.8 ± 41.8mL, p = 0.893) were not different. Four patients needed temporary catheterization for less than 3 days. All of them were able to empty their bladders without significant amount of residuals after a week of the injection. Of the failed cases, 3 patients underwent repeat MUS and 2 had secondary TUI. There were no significant complications related to the procedure.

Conclusion: TUI of bulking agent for the failed MUS showed low cure rate, but the satisfaction was high and the procedure was minimally invasive with no significant complications. This treatment could be an option for selected patients in who were failed MUS with co-morbidity, operative risks, and for patients want to avoid another surgery.

KEYWORDS: Stress urinary incontinence; bulking agent injection