Bladder instillations vs onabotulinumtoxinA injection for interstitial cystitis/bladder pain syndrome: a randomized clinical trial.

BACKGROUND: Interstitial cystitis (IC)/bladder pain syndrome (BPS) is an unpleasant sensation related to the bladder with lower urinary tract symptoms lasting more than 6 weeks, unrelated to an otherwise identifiable cause. The etiology is likely multifactorial including urothelial abnormalities, neurogenic pain upregulation, and potentially bladder and vaginal microbiome alterations. Despite treatment effectiveness of both bladder instillations and intradetrusor onabotulinumtoxinA injection for this condition, a head-to-head comparison has not been performed. OBJECTIVE: To compare the efficacy of bladder instillations and intradetrusor onabotulinumtoxinA injection for treatment of IC/BPS. STUDY DESIGN: Patients with O'Leary-Sant (OLS) questionnaire scores of ≥6, meeting clinical criteria for IC/BPS, and desiring procedural management were randomized to bladder instillations or intradetrusor onabotulinumtoxinA injection. The primary outcome was the difference in OLS scores at 2 months posttreatment between groups. Secondary outcomes included evaluation of sexual function, physical/mental health status, pain, patient satisfaction, treatment perception, retreatment, and adverse event rates. RESULTS: Forty-seven patients were analyzed with 22 randomized to bladder instillations and 25 to onabotulinumtoxinA injection. There were no differences in demographic and clinical characteristics between groups. From baseline to 2 months posttreatment, there was a decrease in OLS subscales in all patients (Interstitial Cystitis Symptom Index [ICSI] -6.3 (confidence interval [CI] -8.54, -3.95), P<.0001; Interstitial Cystitis Problem Index [ICPI] -5.9 (CI -8.18, -3.57), P<.0001). At 2 months posttreatment, patients in the onabotulinumtoxinA group had significantly lower OLS scores compared to those in the bladder instillation group (ICSI 6.3±4.5 [onabotulinumtoxinA] vs 9.6±4.2 [instillation], P=.008; ICPI 5.9±5.1 [onabotulinumtoxinA] vs 8.3±4.0 [instillation], P=.048). The difference in OLS scores between groups did not persist at 6 to 9 months posttreatment. There were no statistically significant differences between baseline and posttreatment time points for the remaining questionnaires. Eight percent of patients who received onabotulinumtoxinA injection experienced urinary retention requiring self-catheterization. Patients who underwent onabotulinumtoxinA injection were significantly less likely to receive retreatment within 6 to 9 months compared to patients who received bladder instillations (relative risk 13.6; 95% CI, 1.92-96.6; P=.0002). There were no differences between groups regarding patient satisfaction, perception of treatment convenience, or willingness to undergo retreatment. CONCLUSION: Both onabotulinumtoxinA injection and bladder instillations are safe, effective treatments for patients with IC/BPS, with significant clinical improvement demonstrated at 2 months posttreatment. Our findings suggest that intradetrusor onabotulinumtoxinA injection is a more effective procedural treatment for this condition than bladder instillation therapy and associated with decreased rates of retreatment.

How to define failure of intradetrusor injections of botulinum toxin A for neurogenic detrusor overactivity.

INTRODUCTION: Neurogenic detrusor overactivity (NDO) has a major impact on patients' quality of life and can lead to upper urinary tract complications. Intradetrusor botulinum toxin type A injections are administered as second-line treatment to these patients following the failure of anticholinergic agents. The aim of the DETOX 2 study is to propose a consensus definition of the failure of intradetrusor botulinum toxin injections for NDO in patients presenting spinal cord injury, spina bifida, or multiple sclerosis (MS) with self-catheterization. METHOD: This study followed the method adopted by the French National Authority for Health for recommendations by consensus. Based on a review of the literature and a preliminary survey, a steering committee compiled a questionnaire and selected a rating group comprising 16 experts from the Neuro-Urology Committee of the French Urology Association (cnuAFU) and Genulf. The experts were asked to complete the online questionnaire. At the end of the first round, all participants came together to discuss any disagreements and a second-round online questionnaire was completed to reach a consensus. RESULTS: Thirteen of the 16 experts approached completed both rounds of questionnaires. A strong consensus was reached for two proposals (median score = 9/10) which were therefore included in the definition from the first round: at least one repeat injection of the same botulinum toxin at the same dose must be given to rule out failure on technical grounds and a duration of efficacy <3 months must be considered a failure. At the end of round 2, a relative consensus was reached regarding the clinical criterion defining failure (median score = 7/10) and the urodynamic criterion of failure (median score = 8/10). An additional proposal was selected during this second round on the need for a voiding diary (median score = 8/10). CONCLUSION: The first consensus definition of failure of an intradetrusor injection of TB-A for NDO has been achieved with this study: persistence of detrusor overactivity with maximum detrusor pressures >40 cm H2O and/or a compliance issue and/or persistence of urinary incontinence and/or urgency and/or a number of daily self-catheterizations >8/day and/or efficacy <3 months. This study will help to standardize research on the failure of the intradetrusor botulinum toxin for NDO in clinical practice and clinical research.

Treatment of refractory overactive bladder with OnabotulinumtoxinA vs PTNS: TROOP trial.

INTRODUCTION AND HYPOTHESIS: We hypothesized that patients with refractory overactive bladder (rOAB) have similar improvement with percutaneous tibial nerve stimulation (PTNS) and OnabotulinumtoxinA (BTX). METHODS: This multicenter cohort study compared BTX and PTNS in women with rOAB. Baseline information included Overactive Bladder Questionnaire (OABq) short form, Urinary Distress Inventory-6 (UDI-6), and voiding diary. Primary outcome was cure, defined as "very much better" or "much better" on the Patient Global Impression of Improvement (PGII) AND a reduction in OABq symptom severity scale (SSS) ≥10 at 3 months after treatment. Assuming 80% power to detect a ten-point difference in OABq-SSS, 80 participants were required per group. RESULTS: A total of 150 patients were enrolled; 97 completed 3 months of therapy and were included. At baseline, BTX patients had more detrusor overactivity (70% vs 40%, p = 0.025), urgency incontinence (UUI; OABq-SSS#6 4 vs 3, p = 0.02, SSS 65 vs 56, p = 0.04), but similar health-related quality of life (HRQL 49 vs 54, p = 0.28), voids (7 vs 8, p = 0.13), and UUI episodes (2 vs 2, p = 1.0). At 3 months, cure rates were similar: BTX 50% vs PTNS 44.2% (p = 0.56). Both groups had improved SSS (-37 vs -29, p = 0.08) and HRQL (31 vs 24, p = 0.14). Patients receiving BTX had a greater improvement in urgency (ΔOABq-SSS#2-3 vs -2; p = 0.02) and UUI (ΔOABq-SSS#6-2 vs -1; p = 0.02). No characteristics were predictive of cure. CONCLUSIONS: BTX resulted in significantly greater improvement in urgency and UUI than PTNS, but no difference in success based on PGII and OABq-SSS, which may be due to a lack of power.

A retrospective longitudinal evaluation of new overactive bladder patients in an FPMRS urologist practice: Are patients following up and utilizing third-line therapies?

AIMS: Third-line therapies are efficacious in improving overactive bladder (OAB) symptoms; however, OAB patients have poor follow-up and rarely progress to these therapies. Clinical care pathways (CCP) may improve OAB follow-up rates and third-line therapy use. We sought to determine how new OAB patients follow up and utilize third-line therapies with the implementation of an OAB CCP in a fellowship Female Pelvic Medicine and Reconstructive Surgery (FPMRS) trained urologist's academic practice. METHODS: We identified new OAB patients using ICD-9 and 10 codes. They were placed into two groups: pre- and post-CCP use. Basic demographic data were collected. Patients were evaluated in a retrospective longitudinal fashion over 12 months to determine follow-up and third-line therapy utilization. RESULTS: A total of 769 new OAB patients (261 pre-CCP and 508 post-CCP) were identified. The mean number of follow-up visits increased significantly at 6 months (0.94 vs. 1.64 visits, p = .001) and 12 months (1.26 vs. 2.46 visits, p < .003). Follow-up rates increased significantly at 3 months (38.7% vs. 50.2%, p = .002). Mean time to third-line therapy decreased significantly (280 days vs. 160 days, p = .016). Third-line therapy utilization therapy rates increased at 6 months (7.7% vs. 13.4%, p = .018) and at 12 months (11.1% vs. 16.5%, p = .044). CONCLUSIONS: New OAB patients follow-up and progress to third-line therapies faster and more frequently with the use of a CCP in an FPMRS-trained urologist practice. However, many OAB patients still fail to follow up and overall utilization of third-line therapies remains low. Future studies are warranted to identify factors to why overall OAB compliance remains low.

Modifications to Botulinum toxin A delivery in the management of detrusor overactivity recalcitrant to initial injections: a review.

PURPOSE: One quarter of patients will not respond to initial intra-detrusor Botulinum toxin A (BTX) injections for detrusor overactivity. Alternative treatment options include long-term catheterization, sacral neuromodulation, urinary diversion or bladder augmentation. Some of these procedures are invasive. This review explores modifications to BTX delivery that can improve outcome. METHODS: A search of Medline, Embase and Cochrane Library to December 2017 was performed according to Preferred Reporting Items for Systematic Review and Metaanalysis (PRISMA) guidelines. Search criteria included, dose escalation, increasing injection site number, trigone injection, switching preparation and alternative methods of BTX delivery. RESULTS: Several modifications to BTX delivery may improve response. There is moderate evidence that increasing the dose from 100 U to 200 U results in statistically better symptom control. Trigone-including injections were associated with significantly improved patient-reported symptom scores, as well as superior results in urodynamic outcomes without risking urinary retention and vesico-ureteric reflux. Switching from onabotulinum (OTA) or abobotulinum (ATA) or vice versa may also improve response in over 50% of patients as shown in limited studies. Increasing the number of injection sites is not beneficial. Indeed, decreasing the number of injections to as low as three sites does not result in decreased clinical outcomes. Injection-free delivery is associated with lower efficacy compared to conventional intradetrusor injections. CONCLUSION: Before contemplating alternative treatments, practitioners can try to improve on BTX delivery. Firstly, the dose can be increased to 200 U; the trigone included in the injection sites and switching brands may also be helpful.

Intradetrusor onabotulinumtoxinA injections for refractory neurogenic detrusor overactivity incontinence: do we need urodynamic investigation for outcome assessment?

OBJECTIVE: To evaluate if urinary continence in patients with refractory neurogenic detrusor overactivity (NDO) incontinence after intradetrusor onabotulinumtoxinA injections is sufficient for appropriate outcome assessment or if urodynamic investigation (UDI) is needed. PATIENTS AND METHODS: A consecutive series of 148 patients undergoing intradetrusor onabotulinumtoxinA injections for refractory NDO incontinence were prospectively evaluated. Patients underwent UDI before and at 6 weeks after onabotulinumtoxinA injections. The primary outcome was the prevalence of maximum storage detrusor pressure (Pdetmax storage) of >40 cmH2 O in continent patients at 6 weeks after treatment. The secondary outcomes were treatment effects on other clinical and video-urodynamic variables. RESULTS: At 6 weeks after intradetrusor onabotulinumtoxinA injections, 98 of the 148 patients (66%) with NDO incontinence were continent. Of these patients, 18 (18%, confidence interval 12-27%) had a Pdetmax storage of >40 cmH2 O. Gender, underlying neurological disorder, and high Pdetmax storage before treatment appear to increase the risk of poor urodynamic outcomes. CONCLUSIONS: Urinary continence is not sufficient for outcome assessment after intradetrusor onabotulinumtoxinA injections, as high intravesical pressures threatening the upper urinary tract may be missed in a relevant proportion of continent patients. Therefore, we strongly recommend UDI as a routine part of the follow-up.

Real-World Use of Intradetrusor Botulinum Toxin Injections: A Population-Based Study from France.

In recent decades, intradetrusor injections of botulinum toxin A (BoNT-A) have been widely applied to treat incontinence in both idiopathic overactive bladder (iOAB) and neurogenic detrusor overactivity incontinence (NDOI). This analysis, based on the French National Hospital Discharge Database (PMSI), aims to describe real-world trends in intradetrusor BoNT-A use between 2014 and 2022. Among 32,864 patients who received at least one intradetrusor BoNT-A injection, 18,320 (55.7%) had conditions coded under iOAB, 13,376 (40.7%) under NDOI, and 1168 (3.6%) under other indications. The overall mean interval between two intradetrusor BoNT-A injections was 9.7 months, ranging from 8.7 months in patients with multiple sclerosis (MS) to 11.5 months in patients with cerebral pathologies. The median number of injections was two (quartile 1-quartile 3, 1-4) in patients with spina bifida, whereas it was five (2-10) in those with MS. Only 31% of patients with iOAB received more than two intradetrusor BoNT-A injections. Regardless of its indication, BoNT-A was well tolerated. Adverse events occurring during or requiring hospitalization included infections (3.8%), hematuria (0.53%), and bleeding episodes necessitating transfusions (0.11%), all recorded within the initial month following BoNT-A injection. Our analysis of the PMSI database highlights a broad spectrum of intradetrusor BoNT-A injection practices.

Intradetrusor Versus Suburothelial Onabotulinum Toxin A in Adults with Neurogenic and Non-neurogenic Overactive Bladder Syndrome: A Meta-Analysis.

PURPOSE: This systematic review and meta-analysis aimed to compare the effectiveness and safety of submucosal injection of onabotulinum toxin A (OnabotA) with intradetrusor injection for overactive bladder syndrome (OAB). METHODS: This systematic review is registered with PROSPERO (CRD42021237964). A licensed librarian surveyed Medline, EMBASE, Scopus, and Google Scholar databases to conduct a comprehensive search. Studies comparing suburothelial and intradetrusor techniques of OnabotA injection for OAB were included, along with clinical and urodynamic variables and complications. The studies were assessed for quality on the basis of Cochrane Collaboration guidelines and evaluated using statistical analysis via a random-effect model and I2 statistic. Data extraction and analysis were conducted using Covidence systematic review platform and Review Manager software. RESULTS: Six studies with 299 patients were included in the systematic review, with four reporting that suburothelial injection of OnabotA was as effective as intradetrusor injection and two reporting intradetrusor injection to be more effective. The meta-analysis found no significant difference between the suburothelial and intradetrusor groups for mean daily catheter or voiding frequency (mean difference: 2.12 [95% confidence interval (CI): -1.61, 5.84]) and the mean number of urgency/urge incontinence episodes (mean difference: 0.08 [95% CI: -1.42, 1.57]). However, a significant heterogeneity was found among the studies. Only the mean volume at first detrusor contraction showed a significant difference, being higher for suburothelial injection (mean difference: 33.39 [95% CI: 0.16, 66.63]). No significant difference was noted for mean compliance, mean bladder capacity, and mean maximum detrusor pressure. Urinary tract infections (UTIs) (p = 0.24) and acute urinary retention (p = 0.92) showed no significant difference between the two groups. The risk of bias varied among the studies. CONCLUSIONS: Suburothelial injection of OnabotA is as effective as intradetrusor injection in improving OAB symptoms, and it has similar complication rates. A higher mean volume of the first detrusor contraction was found in a urodynamic study with suburothelial injection.

Chemodenervation in Urology.

Onabotulinumtoxin A is an effective therapeutic tool for urologic treatment. The toxin exerts multiple effects in the urinary tract system, which contributes to its utility. The toxin can be used to alleviate a variety of pathologic conditions if administered in the appropriate patient population.

Efficacy and safety of intradetrusor onabotulinumtoxinA injection for managing paediatric non-neurogenic overactive bladder: A prospective case-series study.

Objectives: To evaluate the outcome of intradetrusor onabotulinumtoxinA (Botox®; Allergan Inc., Dublin, Ireland) (IDB) injection in children and adolescents with non-neurogenic overactive bladder (OAB) refractory or resistant to treatment. Patients and Methods: In all, 91 patients underwent evaluation using subjective scores and urodynamic studies (UDS), including determination of maximum bladder capacity (MBC) and evaluating the capacity deficit vs the expected bladder capacity (EBC), and uroflowmetry determination of voided volume, maximum urinary flow rate (Qmax) and post-void residual urine volume (PVR). All patients received oxybutynin (0.3-0.5 mg/kg/day) for 3 months and re-evaluated patients who developed drug intolerability, persistence or recurrence of OAB received 100 U IDB injection using 20 injection sites, with trigone and sphincter sparing. All patients were re-evaluated 3-monthly for subjective scoring and at the end of the 12-month follow-up with UDS. Results: In all, 43 patients underwent IDB injection and at the end of the 12-month follow-up the success rate for IDB injection was 90.7%. All patients showed progressively decreasing scores compared to baseline scores. At the 12-month follow-up, MBC, voided volume, and Qmax were significantly higher, whilst capacity deficit and PVR were significantly lower than baseline measures. The frequency of patients satisfied with the outcome of IDB was high. Conclusion: For children with OAB refractory or resistant to biofeedback therapy, anti-cholinergic drugs must be tried first with IDB reserved for cases who fail to respond, are intolerant or recur after medical treatment. IDB using 100 U Botox, at 20 injection sites with trigone and sphincter sparing, is successful with a high satisfaction rate and free of postoperative problems. Abbreviations: EBC: expected bladder capacity; IDB: intradetrusor onabotulinumtoxinA; MBC: maximum bladder capacity; OAB: overactive bladder; OABSS: Overactive Bladder Symptom Score; PPBC: Patient Perception of Bladder Condition; PVR: post-void residual urine volume; TENS: transcutaneous electrical nerve stimulation; Qmax: maximum urinary flow rate; UDS: urodynamic studies; UI: urinary incontinence.

More Than 15 Years of Experience with Intradetrusor OnabotulinumtoxinA Injections for Treating Refractory Neurogenic Detrusor Overactivity: Lessons to Be Learned.

BACKGROUND: Intradetrusor onabotulinumtoxinA (BoNT-ONA) injections have become a well-established therapy for refractory neurogenic detrusor overactivity (NDO). However, little is known about long-term outcome and patients' adherence to this treatment. OBJECTIVE: To assess long-term outcomes of intradetrusor BoNT-ONA injections and patients' adherence to treatment. DESIGN, SETTING, AND PARTICIPANTS: A consecutive series of 52 patients who underwent first intradetrusor BoNT-ONA injections for refractory NDO >10 yr ago were evaluated retrospectively and prospectively at a single university spinal cord injury (SCI) centre. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Primary outcome was current neuro-urologic treatment. Secondary outcomes were urodynamic parameters. For data comparison, the paired/unpaired t test, chi-square test, and McNemar test were used. RESULTS AND LIMITATIONS: Mean duration since first intradetrusor BoNT-ONA injections was 12±2 yr. Most patients (61% [32 of 52]) suffered from SCI, 15% (8 of 52) from spina bifida, 14% (7 of 52) from multiple sclerosis (MS), and the remaining (10% [5 of 52]) from other neurologic disorders. Almost 60% (31 of 52) of all patients are continuing with intradetrusor BoNT-ONA injections but only 14% (1 of 7) of the patients with MS. Lack of clinical and/or urodynamic response (21% [11 of 52]) and switching to another treatment (antimuscarinics and/or neuromodulation) despite appropriate BoNT-ONA efficacy (19% [10 of 52]) were the reasons for discontinuation. In patients continuing BoNT-ONA treatment, the positive effect was sustained after repeat injections (p<0.05). CONCLUSIONS: Although intradetrusor BoNT-ONA injections are a highly effective therapy for refractory NDO, approximately 40% of the patients discontinue treatment over time. All prospective neurologic patients should be given this information, and it needs to be considered in the treatment decision-making process. PATIENT SUMMARY: Approximately 60% of the patients treated with intradetrusor onabotulinumtoxinA injections for refractory neurogenic detrusor overactivity continue this therapy long term with good therapeutic effects. STUDY REGISTRATION NUMBER: NCT01293110.

Effects of onabotulinumtoxinA on cardiac function following intradetrusor injections.

OnabotulinumtoxinA intradetrusor injections are considered a highly effective localized therapy for refractory detrusor overactivity. However, despite evidence for distant systemic effects of onabotulinumtoxinA, little is known on potential systemic side effects following intradetrusor injections. Given that onabotulinumtoxinA is a highly potent toxin this is an important safety issue specifically with regard to repeat injections and parallel treatments with botulinum toxin. Hence, it was the purpose of this prospective study to investigate, using heart rate variability (HRV) analysis, whether onabotulinumtoxinA causes systemic effects on cardiac function following intradetrusor injections. Patients with neurogenic detrusor overactivity (NDO) and age-matched healthy controls were recruited. Concomitant medication and diseases affecting the cardio-vascular system were exclusion criteria. A 3-channel resting electrocardiogram (ECG) was recorded in supine position for 15min during four consecutive visits: 1) 2weeks prior onabotulinumtoxinA intradetrusor injections, 2) 10min prior injections, 3) 30min after injections, and 4) 6weeks after injections. NDO patients received intradetrusor injections (300units Botox®) between visits 2 and 3. The control group had no intervention. Short-term (5min) HRV analysis included assessment of frequency and time domain parameters. Statistical analysis was performed using ANOVA with repeated measures and the t-test. Due to multiple comparisons, α was corrected to 0.0125 (Bonferroni method). Twelve healthy volunteers (5♀, 7♂; 46±12years old) and 12 NDO patients (5♀, 7♂; 46±13years old) completed all measurements. Comparing both groups, resting heart rate was significantly higher in the patients group at visit 4 only. No further significant differences in time and frequency domain parameters were discovered. Within the NDO group, standard deviation of the normal to normal intervals (SDNN) in the ECG demonstrated a significant decrease (1.70 to 1.53ms, p=0.003) from visit 3 to 4, whereas the total power (TP) significantly increased (3.05 to 3.29ms2, p=0.009) from visit 2 to 3. This increase subsided until visit 4. STUDY LIMITATIONS: single treatment investigation under resting conditions only. In conclusion, onabotulinumtoxinA intradetrusor injections do not seem to affect resting state cardiac function. Short-term changes such as total power might rather result from natural cardio-vascular responses to the procedure itself (e.g. discomfort, stress). Further detailed investigations also under physical stress and repeated injections are necessary to fully exclude systemic cardiac side effects of onabotulinumtoxinA intradetrusor injections.

Botulinum Toxin A Intradetrusor Injection for Treating Neurogenic Detrusor Overactivity, A Single Centre Experience.

OBJECTIVES: To evaluate the efficacy and safety of Botulinum Toxin A (BoNTA) intradetrusor injections in patients with neurogenic detrusor overactivity. METHODS: All patients provided clinical history and voiding diary, submitted to clinical examination, urine culture; serum creatinine; imaging, including plain abdominal X-rays, abdomino-pelvic ultrasonography and voiding cystourethrogram; and urodynamic tests (CMG) . They were managed by intradetrusor injections of BoNTA. For the typical patient, 300 units of BoNTA were injected through 30 injections of 10 u/mL intradetrusally into equally spaced sites of the bladder wall, excluding the trigone, under cystoscopic guidance. Patients were commenced clean intermittent catheterizations (CICs) every 4-6 h post-injection. Follow up included voiding diaries, abdomino-pelvic ultrasonography, serum creatinine and CMG, were completed for all patients at 6 and 12 weeks. This study used IBM SPSS Version 20.0 for statistical analysis. RESULTS: Forty-five patients (28 males and 17 females) with a mean age of 19.6 years were subjected to BoNTA intradetrusor injections. A good clinical response (dry patient either completely or more than 50% of the period between CICs) was observed in 68.9 and 66.7% of the patients after 6 and 12 weeks of follow up, respectively. In the group that responded well, the mean bladder volume increased post-injection by 48.2% and the mean maximum intravesical pressure decreased to 35.3 cm H2 O, a 33.4% improvement. No patients had side-effects related to BoNTA or to the procedure, and no patients experienced a deterioration of their renal functions. CONCLUSIONS: Intradetrusor BoNTA injections provide a good clinical response. The urodynamic parameters significantly improved in patients with neurogenic detrusor overactivity.

[Intra-detrusor injection of botulinum toxin for female refractory idiopathic overactive bladder syndrome]. / Injections intra-détrusoriennes de toxine botulinique pour l'hyperactivité vésicale idiopathique réfractaire de la femme.

INTRODUCTION: Botulinum toxin-A detrusor injections are now approved for use (extension of marketing authorization) in the management of refractory idiopathic overactive bladder. The goal of the current study was to study the value and efficacy of this therapy. PATIENTS AND METHODS: A literature review was performed on Medline, Embase and Cochrane databases, using the following keywords: botulinum toxin; overactive bladder syndrome; urinary incontinence; detrusor injection. RESULTS: The recommended first step dose is 50 units of BOTOX(©) (dose selected for tolerance assessment). However, the cure rates for urge incontinence are greater with 100 units. Before proposing an injection, it is recommended to ensure the feasibility and acceptability of self-catheterisation by the patient, because of the risk of urinary retention (6%). The administration of BOTOX(©) comprises an intra-detrusor injection using a cystoscope, performed under local anesthesia. Clinical improvement is generally observed in the first two weeks after the injection. Patients should be considered for reinjection when the clinical effect of the previous injection has diminished, approximately 6-9 months after the first injection. An injection of 100 units may be considered when the clinical benefit of the 50-unit injection is not satisfactory concerning incontinence symptoms. CONCLUSION: Botulinum toxin detrusor injections may be offered to women who develop refractory OAB.