The effect of spinal cord-injury level on the outcome of neurogenic bladder treatment using OnabotulinumtoxinA.

Aim: The aim was to report the effectiveness and safety OnabotulinumtoxinA (Botox, Allergan, Inc., Irvine, CA, USA) intradetrusor injections in spinal cord-injured (SCI) patients with refractory neurogenic detrusor overactivity. And to assess the result based on SCI level.

Materials And Methods: We reviewed the chart of 103 patients with neurogenic bladder secondary to SCI at the rehab center who received OnabotulinumtoxinA in our Neurourology Department for treatment of lower urinary tract symptoms between January 2007 and December 2013. All patients had a clinical examination, urinalysis, and an urodynamic study at baseline and 3 months after treatment as well as a visual analogue scale (VAS; range scale: 0-10) and a bladder diary checked for 3 days. 300 IU of OnabotulinumtoxinA, detrusor muscle injections were performed in 30 sites under cystoscopic guidance. Outcome measures included frequency of urge urinary incontinence collected by bladder diaries; changes in urodynamic parameters such as maximum cystometric bladder capacity, reflex volume, maximum detrusor pressure; side-effects; antimuscarinic drug consumption and quality of life (QOL) measured with VAS.

Results: The study includes 32 female and 71 male with a mean patient age of 29 years (range: 18-56 year). The effect of Botox injection on bladder function was observed within 1-2 week after treatment. The urodynamic parameters were improved significantly after treatment compared with baseline values. There were significant reductions in the frequencies of incontinence episodes after treatment as seen in the voiding diary. A significant improvement in patient satisfaction was found after treatment which was expressed on the VAS assessment, with an improvement of the mean of 3 points. Patients with thoracic and lumbar injury have better result compare to cervical injury patients. The earliest recurrence of clinical symptoms was at 10 weeks. Overall, the mean duration of symptomatic improvement was 8 (2.5-21) months.

Conclusion: Intradetrusor onabotulinumtoxinA injections are an effective and well-tolerated treatment for neurogenic overactive bladder that will increase patient satisfaction and improve QOL with persisted clinical efficacy for more than 8 months.