Neuromodulation for intractable OAB.

To review the current status of sacral neuromodulation (SNM) in the treatment of intractable overactive bladder symptoms, the PubMed English-language literature was used to address efficacy, technical issues, alternative techniques, the mechanism of action, adverse events, the cost-effectiveness, and current considerations on the use of SNM as second-line treatment in OAB. Several studies attest to the short- and long-term efficacy of SNM in reducing urgency incontinence and the remaining OAB symptoms. Few, medium-sized sample, randomized controlled trials exist. Little is known about long-term patient satisfaction from SNM and prognostic factors have not been identified. Technical advances have significantly improved patient selection and outcomes, as well as complication rates, but revision rates still remain high. The mechanism of action remains largely unknown, but appears to be associated with reorganization of spinal reflexes and regulation of cortical activity. Reports on cost-effectiveness are conflicting. Less invasive forms of SNM may offer a viable alternative to central SNM. In conclusion, current evidence supports the short- and long-term efficacy of SNM in treating intractable OAB, but further research is needed to improve patient selection, identify prognostic factors, clarify the mechanism of action and reduce complications and revision rates.