To identify the success rate of sacral nerve modulation in patients with an overactive bladder (OAB)

Retrospective data was collected between January 2013 till January 2018 (5-year period) in the uro-neurology department. All the patients were diagnosed with OAB identified using clinical history, bladder diaries and cystometography. All patients had failed conservative and medical management in the past. All patients underwent sacral nerve modulation (SNM) at the same unit under a single surgeon. This was carried out using the two-stage approach, with electrode insertion (stage 1) followed by battery insertion (stage 2) if stage one was deemed to be successful. The primary outcome measure was success rate of SNM. This was identified using improvement in quality of life as well as objectively using bladder diaries and flow rate. The failure rate was separated into primary failure after stage 1, true failure of the electrode and secondary failure (after insertion of the battery). Secondary complications were also identified including infection, pain and medical complications.

A total of 67 patients were identified in this study of which 64 patients were women and 3 were male. The overall success rate for SNM in patients with OAB was 63%. In male patients it was 67% whereas in women it was 63%. The overall primary failure rate was 25% and secondary failure rate was identified as 12%. The overall infection rate was 3%. 2 patients complained of battery site pain and 1 patient requested removal of the device despite significant improvement in symptoms. There were no other significant medical complications identified.

There was significant improvement in OAB in both male and female patients with sacral nerve modulation. The overall infection rate of 3% is an appropriate risk in this surgery.

Sacral nerve modulation has a good success rate in patients with an overactive bladder and should be considered inpatients where conservative and medical management has failed and where treatment with Botulinum toxin has either failed or the patient has declined it.