Overactive bladder treatment: application of methylene blue to improve the injection technique of onabotulinum toxin A

Outcomes of a single trigone-only vs. 20 trigone-sparing injections of OnabotulinumtoxinA for refractory overactive bladder (OAB)

PURPOSE

To compare the safety and durability of a single intravesical trigonal-only versus 20 trigone-sparing injections of OnabotulinumtoxinA (BTA) for refractory OAB.

METHODS

A chart review of all idiopathic OAB patients treated with BTA from January 2016 to December 2018 was performed. Outcomes measures included: inter-injection interval, post-void residual (PVR), urinary tract infections (UTI), urinary retention requiring catheterization, and procedure time (min). Statistical analyses were performed using independent sample t-tests.

RESULTS

Baseline characteristics were comparable for the two groups, data on 69 treatments (19 patients trigone-only) were compared to 105 treatments (26 patients trigone-sparing). There were no differences in the inter-injection intervals or rates of UTI. The trigone-only group exhibited a lower mean PVR (113 ml vs 160 ml, p < 0.02), lower proportion with PVR > 150 ml (23% vs. 39%, p < 0.03), lower rate of urinary retention (5.3% vs. 17.4%, p < 0.02), and shorter procedure time (4.3 min vs. 5.7 min, p < 0.01). There were no cases of vesico-ureteral reflux.

CONCLUSION

While interpretation remains speculative, the results of this observational study suggest that a single trigone-only injection appears to be as safe and durable as multiple trigone-sparing injections but maybe quicker to perform and appears to have a lower impact on voiding function. Larger series and adequately powered prospective randomized clinical trials are warranted to validate the findings of this pilot study.

Trigonal-sparing versus trigonal-involved Botox injection for treatment of idiopathic overactive bladder: A randomized clinical trial

OBJECTIVE

To evaluate safety and efficacy of trigone-involved Botox injections in comparison with trigone-sparing injections in refractory idiopathic overactive bladder (OAB).

MATERIALS AND METHODS

One hundred and three patients randomly received a 100-IU intradetrusal injection of Botox either sparing the trigone (52 patients) or involving the trigone (51 patients). Patients were prospectively evaluated at 1, 3, and 6 months. Efficacy was evaluated by 3-day voiding diaries, OAB symptom score (OABSS), and pressure flow study. Any complications were recorded. An ascending cystogram was done at 3 months for detection of vesicoureteral reflux. Urinary tract infection (UTI) was estimated on urine culture basis. Primary outcome was the difference of total OABSS at 3 months.

RESULTS

The mean age ± SD was 34.3 ± 10 years (range 18-59 years). There was a reduction of episodes of all components of OAB in both groups in comparison with baseline by the end of the study but without significant difference between both groups. The trigonal-sparing group had less score of frequency compared with the trigonal-involved group throughout the study period (P < .05). There was no difference in OABSS at 3 months (1.5 ± 0.4 vs 1.6 ± 0.3, P .875). Two patients in the trigonal-involved group out of 51 (3.9%) were in need of clean intermittent catheterization because of voiding difficulty and a postvoid residual > 200 mL. There was a higher rate of UTI in the trigonal-involved group ranging from 5.6% up to 11.7% at each follow-up visit. No patient had reflux.

CONCLUSION

Trigone injections are not superior to trigone-sparing injections. On the contrary, the incidence of UTI and voiding difficulty were higher. The concept of reflux induced by trigonal injection has not been proven.

Intravesical Loss of OnabotulinumtoxinA During Endoscopic Intradetrusor Injection - A Multicenter Experience

Purpose

To evaluate intravesical loss of onabolunumtoxinA (onaBTA) during endoscopic injection into the bladder wall for treatment of neurogenic detrusor overactivity (NDO). The intraluminal loss of onaBTA cannot be determined directly, therefore we added methylene blue (MB) to reconstitute onaBTA. Subsequently we used spectrophotometry to determine the total amount of MB in the irrigation fluid, which allowed us to calculate total intraluminal loss of onaBTA.

Methods

The study population was consisted of 48 patients with NDO. The mean age was 36.6±8.9 years. Forty-two patients suffered from NDO due to spinal cord injury and 6 patients suffered from multiple sclerosis. Each patient received 200 units of onaBTA administered by 30 endoscopic injections (1 mL per injection) using a 23-G needle. The entire volume of irrigation fluid was collected and spectrophotometry was used to determine the MB concentration. The total amount of injected onaBTA, total amount of irrigation solution and the known amount of MB used during reconstitution, allowed for the determination of intravesical loss of onaBTA.

Results

Forty-five patients were included in the final analysis. The mean volume of irrigation fluid was 603.33±400.14 mL. The mean absorbance was 0.14±0.12 with the mean MB concentration 0.19±0.18 mg/L. The mean calculated loss of onaBTA was 4.14±4.11 units.

Conclusions

The endoscopic injection of onaBTA marked by MB into the bladder wall is associated with minimal intravesical loss of the agent, representing less than 3% of the administered dose of MB. This may reflect the amount of the onaBTA detected in the irrigation fluid.

Application of methylene blue as an improvement of the injection technique of botulinum toxin A in the treatment of refractory idiopathic overactive bladder: prospective, single-blind (patient-blind), randomized trial

Introduction

Refractory idiopathic overactive bladder (RIOAB) is a common condition with a significant negative impact on quality of life. Intravesical injection of botulinum toxin A (BTX-A) is widely used as an intervention for these cases. In the standard method the drug solution is colorless. The addition of dye such as methylene blue (MB) facilitates visualization during the procedure and may have a beneficial effect.

Aim

To evaluate the injection of BTX-A with the addition of methylene blue (MB) against a standard method in the treatment of RIOAB.

Material and methods

In this 1-center, single-blinded, randomized controlled trial, we recruited 80 patients with RIOAB. A total of 39 were assigned to injection into the bladder wall of 100 U BTX-A with MB (in 9.5 ml normal saline + 0.5 ml MB), and 41 were assigned to BTX-A 100 U alone (in 10 ml normal saline). Cystoscopy with a submucosal injection of the solution was performed systematically, including the bladder triangle. Participants were assessed 6 and 12 weeks after the treatment using a Likert scale and OABSS questionnaire.

Results

Significant improvement was similar (result of 1 or 2 on the Likert scale) and was achieved in 66.7% and 69.2% after 6 weeks and in 63.9% and 64.1% after 12 weeks in the BTX-A + MB group and only-BTX-A group, respectively. There was a significant difference between the two groups (p = 0.049) in the total number of patients with complications: 2 (5.6%) vs. 9 (23.1%).

Conclusions

The addition of MB to BTX for treatment of RIOAB patients does not influence treatment efficacy, while it limits the risk of complications.