Intravesical resiniferatoxin versus botulinum-A toxin injections for neurogenic detrusor overactivity: a prospective randomized study

We investigated the effectiveness and safety of intravesical resiniferatoxin (Sigma Chemical Co., St. Louis, Missouri) and botulinum-A toxin injections into the detrusor muscle in a group of spinal cord injured patients with neurogenic detrusor overactivity unresponsive to conventional anticholinergic therapy.A total of 25 patients were randomly assigned to receive intravesically 0.6 microM resiniferatoxin in 50 ml of 0.9% NaCl or injections into the detrusor muscle of 300 units botulinum A-toxin diluted in 30 ml 0.9% NaCl. Clinical evaluation and urodynamics were performed at baseline, and at 6, 12 and 18 months after treatment.In both arms there was a significant decrease in catheterization and incontinent episodes, and a significant increase in first detrusor contraction and maximum bladder capacity at 6, 12 and 18-month followup. There were no local side effects with either treatment. Botulinum-A toxin induced a significant decrease in the frequency of daily incontinence episodes (p0.05), a significant increase in first uninhibited detrusor contraction (p0.01) in maximum bladder capacity (p0.01), and a significant decrease in maximum pressure of uninhibited detrusor contractions (p0.01) compared to resiniferatoxin at 6, 12 and 18-month followup.In spinal cord injured patients with refractory neurogenic detrusor overactivity, intravesical resiniferatoxin and botulinum-A toxin injections into the detrusor muscle provided beneficial clinical and urodynamic results with decreases in detrusor overactivity and restoration of urinary continence in a large proportion of patients. Botulinum-A toxin injections provided superior clinical and urodynamic benefits compared to those of intravesical resiniferatoxin.