To investigate the effectiveness of botulinum toxin type A injections to external sphincter in pediatric patients  who has dysfunctional voiding.

In our clinic, pediatric patients diagnosed with dysfunctional voiding and had undergone external sphincter injection of botulinum toxin type A were analyzed retrospectively. Age of patients, voiding dysfunction symptom scores, capacity, peak flow rate, average flow rate, residual urine, urodynamic data and frequency of infections were recorded.

The mean age of 16 girls and six boys were 10,7 ± 3,8 years. Preoperative daily incontinence episodes and symptom scores were calculated as 0,72 ± 0,4/day and 23,5 ± 5,3 respectively. Botulinum toxin type A was injected only to external sphincter in 13 patients and to both bladder and external sphincter in nine patients who had detrusor instability and/or low bladder capacity. Average amount of injected botulinum toxin type A into bladder was 65 ± 21,2 Units and to external sphincter was 41,6 ± 13,2 Units. Mean follow-up of the patients was 5,3 ± 2,7 months. 18 patients received anticholinergic therapy for 5.8 ± 4 months preoperatively. Postoperative symptom score and daily incontinence episodes were seen to decrease to 8,2 ± 7 (p:0,01) and 0,2 ± 0,4 (p:0,003). Bladder capacity increased from 260 ± 103 mL to 308 ± 117 mL (p = 0,01). Residual urine volume decreased from 53 ± 106  mL to 50 ± 105 mL (p = 0.2). Peak flow rate increased from 21 ± 10 mL/sec to 23 ± 10 mL/sec (p = 0.1). The average flow rate changed from 11 ± 7 mL/sec to 10 ± 5 mL/sec (p = 0.7). EMG findings were improved in 80% of patients in the first month control. Seven of the nine patients who had infection stories showed improvement of infection. There was no postoperative complication according to Clavien classification.

Mean follow-up of the patients was 5,3 ± 2,7 months. 18 patients received anticholinergic therapy for 5.8 ± 4 months preoperatively. Postoperative symptom score and daily incontinence episodes were seen to decrease to 8,2 ± 7 (p:0,01) and 0,2 ± 0,4 (p:0,003). Bladder capacity increased from 260 ± 103 mL to 308 ± 117 mL (p = 0,01). Residual urine volume decreased from 53 ± 106  mL to 50 ± 105 mL (p = 0.2). Peak flow rate increased from 21 ± 10 mL/sec to 23 ± 10 mL/sec (p = 0.1). The average flow rate changed from 11 ± 7 mL/sec to 10 ± 5 mL/sec (p = 0.7). EMG findings were improved in 80% of patients in the first month control. Seven of the nine patients who had infection stories showed improvement of infection. There was no postoperative complication according to Clavien classification.

Injection of botulinum toxin type A is safe and effective treatment in reduction  incontinence episodes and correction voiding dysfunction symptom scores in pediatric patients with dysfunctional voiding.