Experience with injections of botulinum toxin type A into the detrusor muscle.

INTRODUCTION: We evaluated the effects of intra-vesical injection of botulinum toxin type A in the detrusor muscle in patients with neurogenic overactive bladder (OAB), patients with non-neurogenic overactive bladder and patients with interstitial cystitis.

MATERIALS AND METHODS: Between January 2003 and December 2006 we treated 30 patients with 100 I. U. to 300 I. U. of botulinum toxin A in the detrusor muscle. Patients were clinically and urodynamically followed up for 4, 12 and 36 weeks thereafter.

RESULTS: Neurogenic overactive bladder: of the 19 injected doses, 18 (94.7%) in 7 patients were judged as effective, and 1 (5.2%) of 200 U of BTX-A was judged as ineffective. Mean bladder volume increased from 137 to 396 ml. Non-neurogenic overactive bladder: of 7 injections, 6 (85.7%) were judged effective in 5 patients. Mean bladder volume increased from 149 to 322 ml. Interstitial cystitis: in all 4 patients the treatments were deemed ineffective.

CONCLUSIONS: Injecting 300 units of BTX-A into 30 sites in the muscle located in the body of the bladder region is effective for neurogenic bladder patients with intermittent catheterization who have urge and reflective types of incontinence. Injections of 100 and 200 units of BTX-A to treat non-neurogenic overactive bladder with urinary incontinence provided together without retention. The optimal dose of BTX-A requires further investigation. Injection with 200 units of BTX-A was not useful against interstitial cystitis. None of the patients developed any adverse effects after injecting the bladder wall with BTX-A.