Objectives: To investigate the effect of botulinum toxin type A bladder injections in the treatment of overactive bladder syndrome in the absence of detrusor overactivity.
Methods: The subjects were 7 women (average age 61.1 years, range 51 to 79) who presented with overactive bladder symptoms. Their disorder had been refractory to several classic treatment options. Urodynamic examination excluded detrusor overactivity. A total of 300 U BTX-A (Botox) was injected, of which 50 to 75 U was injected as quadrant injections into the external sphincter muscle to avoid the postoperative need for catheterization in the case of high postvoid residual urine volume. For follow-up, complete urodynamic studies were performed, and a bladder diary and validated incontinence questionnaires were given to patients at all visits at 1, 3, and 6 months.
Results: The bladder diaries indicated a clear reduction in daytime frequency and nocturia and a reduction in pad use. The maximal voiding volume increased significantly. The urodynamic examinations showed a significant increase in volume when the first and the strong desire to void were expressed. The maximal bladder capacity increased by 20% in 3 months. In the questionnaires, 5 of the 7 patients reported better urine control after therapy, and 6 would have chosen this therapy again for their condition. The overall satisfaction score (on a scale of 0 to 10) averaged 6.8. No side effects, such as urine retention, occurred.
Conclusions: Botulinum-A toxin injection has positive effects in treating overactive bladder symptoms without detrusor overactivity. The effects were seen not only in urodynamic measures but also in patient satisfaction.