Bladder Neck Injections for Stress Urinary Incontinence, a Retrospective Cohort Study
Scott V, Tyagi V, Guerrero K
Background
Bladder Neck Injections (BNI) are a minimally invasive treatment for Stress Urinary Incontinence (SUI). The treatment involves the injection of an agent into the urethral wall leading to narrowing. They are usually done under local anaesthetic. Duration of treatment is limited and may result in repeat treatments. This is a retrospective cohort study looking at the use of BNI in a tertiary setting.
Method
Retrospective case note review of all cases of BNI (n=59) from 2012-2014. Data was analysed using Wizard Statistics programme.
Results
35 (59.3%) of women had symptoms of Stress Urinary Incontinence (SUI) and 24 (40.7%) had Mixed Urinary Incontinence (MUI) i.e. SUI and Overactive Bladder Symptoms. This cohort of patients had a significant prevalence of co-morbidities and therefore BNIs were felt to be the least invasive and therefore, safest means of treatment.
The mean age was 65 years (range 29 – 65 years) and the mean BMI was 30 (range 18 – 60) with no statistically significant differences between SUI and MUI groups (p=0.31 & p=0.25 respectively).
The average Maximal Urethral Closure Pressure (MUCP) for all patients who had urodynamics performed was 38cmH20 (range 2-98cmH2O) suggesting an element of Intrinsic Sphincter Deficiency (ISD) in this cohort. MUCP was marginally higher in the SUI group (42cmH20) than the MUI group (30cmH20).
Success Rates
10 patients (17%) failed to return for follow-up (FU) and are excluded from further analysis. 27 patients (55%) reported significant improvement in their symptoms following treatment. Mean treatment duration was 20 weeks (range 2 weeks to 2 years). 15 patients who had not had sufficient symptom improvement following first treatment underwent repeat BNIs. Only 10 returned for FU: 60% reported successful improvement in their symptoms.
22 patients (45%) reported no improvement in symptoms. 9 went on to have repeat injections with 5 patients reporting no success after this second injection. 55.6% still had no benefit from the second injection.
There was similar success rates between the SUI and MUI groups.
There was no correlation seen between MUCP and successful treatment (p=0.9).
Complications
Post-operative complications were reported by 10 patients (22%). 8 patients (16%) experienced urinary retention post-procedure, most settling within the first week.
2 patients (4%) experienced urethral pain which settled with expectant management.
Quality of Life (QoL) Questionnaires
The standardised disease-specific QoL ICIQ-SF was used, but poorly completed by patients. Analysis of correctly completed pre- & post-treatment sets showed a reduction in scores reflecting symptom improvement following treatment (16.12 vs 9.89).
Conclusion
This cohort of women have a high level of intrinsic sphincter deficiency. The overall success rate for treatment was 55% with the average duration of success being 20 weeks. Our findings are similar to what is seen in literature, that BNIs have limited success rates and duration of success, however given the cohort of patients treated it remains a treatment means when other options are limited.