These authors contributed equally to this work.
Botulinum toxin A modulates afferent fibers in neurogenic detrusor overactivity
Article first published online: 28 DEC 2011
© 2011 The Author(s). European Journal of Neurology © 2011 EFNS
European Journal of Neurology
Volume 19, Issue 5, pages 725–732, May 2012
How to Cite
Conte, A., Giannantoni, A., Proietti, S., Giovannozzi, S., Fabbrini, G., Rossi, A., Porena, M. and Berardelli, A. (2012), Botulinum toxin A modulates afferent fibers in neurogenic detrusor overactivity. European Journal of Neurology, 19: 725–732. doi: 10.1111/j.1468-1331.2011.03618.x
- Issue published online: 17 APR 2012
- Article first published online: 28 DEC 2011
- Received 13 September 2011 Accepted 4 November 2011
- bladder afferents;
- botulinum toxin A;
- Parkinson’s disease;
- spinal cord injury
Background: Although botulinum toxin (BoNT/A) injected into the detrusor muscle improves overactive bladder symptoms in patients with neurogenic detrusor overactivity, how it does so remains unclear. In this study, we investigated whether BoNT/A improves detrusor overactivity by modulating bladder afferent activity.
Methods: To do so, during urodynamic assessment, we tested the soleus muscle Hoffmann (H) reflex during bladder filling before and after intradetrusor BoNT/A in patients with Parkinson’s disease (PD) and in patients with complete chronic spinal cord lesion (SCI) and detrusor overactivity refractory to conventional therapy. Healthy subjects underwent H reflex studies during urodynamic assessment and acted as controls.
Results: Our findings show that BoNT/A injected into the detrusor muscle effectively reduces clinical overactive bladder symptoms in patients with PD and SCI. In healthy subjects and patients with PD, bladder filling [at maximum cystometric capacity, (MCC)] significantly decreased the H reflex size, whereas in patients with SCI, it slightly facilitated the H reflex size. At MCC, in patients with PD, BoNT/A significantly reduced the expected H reflex inhibition, whereas in those with SCI, BoNT/A turned the H reflex facilitation at maximum bladder filling into a slight inhibition.
Conclusions: These findings show that BoNT/A injected into the detrusor muscle in patients with PD and SCI modulates bladder afferent activity. Modulation of bladder afferents possibly explains why BoNT/A improves detrusor overactivity.