Abstract
Purpose: This study aimed to identify the predictive factors for successful or failed treatment outcomes following intravesical injection of botulinum toxin A (BoNT-A) through an analysis of baseline video urodynamic characteristics and parameters. Methods: This study retrospectively analyzed the therapeutic outcomes of intravesical BoNT-A injection in patients who had an overactive bladder (OAB), who were diagnosed with detrusor overactivity (DO), and who had been refractory to OAB medications or intolerant of the adverse events associated with them. Treatment outcomes were classified as successful, improved, or failed according to the patients' subjective report of improvement in OAB symptoms at three months post-injection. The patients were split into male and female cohorts and neurogenic or non-neurogenic DO for data analysis. The video urodynamic study characteristics and parameters were compared across the successful, improved, and failed subgroups. Results: This study included 571 patients who received intravesical BoNT-A injections for treating their OAB and urodynamic DO, of which 272 were men and 299 were women. The treatment outcome of BoNT-A injection was successful in 55.7%, improved in 27.8%, and failed in 16.5% of the patients. Patients with urodynamic detrusor underactivity (DU) and neurogenic DO due to diseases of the central nervous system did not usually achieve a successful outcome. The following factors predicted successful treatment outcomes following BoNT-A injection: lower baseline detrusor pressure, higher maximum flow rate (Qmax), larger voided volume, and smaller post-void residual (PVR) in men; larger voided volume and smaller PVR in women. Conclusions: The therapeutic success of intravesical BoNT-A injection for treating refractory OAB can be predicted by lower Pdet, higher Qmax, larger voided volume, and smaller PVR in men and by higher Qmax and smaller PVR in women. Patients with neurogenic DO and DU usually have unsuccessful treatment outcomes.