Botulinum-A toxin injection into the detrusor: a safe alternative in the treatment of children with myelomeningocele with detrusor hyperreflexia

Abstract

Purpose: We prospectively evaluated the efficacy and durability of botulinum-A toxin in the treatment of detrusor hyperreflexia in children with myelomeningocele (MMC).

Materials and methods: This study involved 15 patients with MMC (10 male and 5 female, mean age 5.8 years), all nonresponders to orally and intravesically administered anticholinergic medication and all on clean intermittent catheterization. Pretreatment assessment included a videourodynamic evaluation, an incontinence score and a mercaptoacetyltriglycine-3 renal scan. We injected 10 U/kg to a maximum of 360 U of botulinum-A toxin into the detrusor at 25 to 40 sites, sparing the trigone. Followup lasted between 12 and 30 months. All children underwent a urodynamic reevaluation, an assessment of the bladder capacity and an incontinence score at 3, 9 and 12 months after the first injection. A second intravesical injection was administered after 12 months and followup repeated as in the first year.

Results: After the first injection treatment mean bladder reflex volume increased from 72.00 +/- 28.12 ml to 298 +/- 32.45 ml (mean +/- SD, p <0.001). Maximum detrusor pressure decreased from 78.76 +/- 23.14 cm H2O to 42.76 +/- 24.34 cm H2O (p <0.001). Maximum bladder capacity increased from 136.34 +/- 45.71 ml to 297.02 +/- 87.17 ml (p <0.001). Detrusor compliance increased from 18.29 +/- 27.19 ml/cm H2O to 51.17 +/- 38.17 ml/cm H2O (p <0.001). Of the 15 patients 13 became completely dry with CIC. The remaining 2 patients improved from score 3 to 1. Results after 9 months were similar to those obtained after 3 months. Mean durability of the effect of the drug was 10.5 months after the first as well as after the second intravesical injection.

Conclusions: Botulinum-A toxin is a safe alternative in the management of detrusor hyperreflexia in children with MMC. The preliminary results regarding urodynamic parameters and continence have been promising.