Abstract: PD64-06
Sources of Funding: NIH grant K12 DK0083014

Introduction

Augmentation cystoplasty has been used in the treatment of refractory neurogenic and overactive bladder. In some patients, symptoms may persist or recur after the surgery, and there is little guidance on management in this setting. In this study, we reviewed the use of Onabotulinum Toxin A (BTX-A) in patients with prior bladder augmentation.

Methods

Retrospective chart review was performed at two institutions, identifying patients with history of augmentation cystoplasty who underwent intravesical BTX-A injection. Data collected included demographics, preoperative and postoperative findings.

Results

22 (17 female, 5 male) patients with mean age 36.8 years (range 18-65) and history of prior augmentation cystoplasty were identified. Etiology of bladder dysfunction included: congenital neurogenic bladder (59%), spinal cord injury (14%), multiple sclerosis (4%), and idiopathic (23%). Indications for BTX-A were urge urinary incontinence and refractory storage symptoms in 15 and 7 patients, respectively. 18/22 patients completed urodynamic studies (UDS) prior to BTX-A injections. Mean maximum cystometric capacity was 298 cc. Decreased compliance and detrusor overactivity were noted in 6 (33%) and 9 (50%) patients, respectively. Patients underwent injection of 200-300 units of BTX-A. Combined intradetrusor and intra-augment injections were done in 11 patients, the remaining 18 patients received only intradetrusor injections. 18 patients (82%) reported improvement in subjective parameters (frequency, urgency, incontinence). There was no significant difference in subjective outcome associated with site of injection (p=0.5, chi-square). No patients had adverse events associated with systemic absorption of BTX-A. One patient had persistent detrusor overactivity, poor compliance, and hourglass configuration on post-BTX-A UDS, and required repeat augmentation cystoplasty. 17 (77%) patients underwent repeat injections; on average, patients underwent 3.3 injections with interval of 8.8 months between injections.

Conclusions

BTX-A injection was shown to subjectively improve refractory storage symptoms and continence after augmentation cystoplasty in the majority of patients. In this multi-institutional cohort, patients had good subjective response regardless of site of injection (combined versus intradetrusor only), and most patients went on to undergo repeat injections. Prospective studies are needed to better evaluate the efficacy and ideal sites of BTX-A injection in the setting of augmentation cystoplasty.

Funding

NIH grant K12 DK0083014