Neuromodulation Outcomes in Male Patients with Chronic Urinary Retention

OBJECTIVES:

To assess the outcome of two-stage sacral neuromodulation (SNM) in men with chronic urinary retention (CUR) and factors affecting the response.

MATERIAL AND METHODS:

Data were collected from 21 male patients with complete or partial CUR who underwent two-stage SNM between 2006 and 2014. The implanted lead was connected to a temporary battery (stage-1) and they were assessed over a period of 3-12 weeks. Those who had a residual volume of ≤100 mL, had an implantable pulse generator sited (stage-2). Patients were followed up at 3 and 6 months initially, and 12 monthly thereafter. The following parameters were analyzed: age, onset of symptoms, precipitant causes for CUR, type of retention, associated voiding dysfunction and opiate intake.

RESULTS:

Surgery was the main precipitating cause of CUR in 5 (24%) patients. Stage-1 SNM restored complete efficient voiding in 14 patients (66.7%) out of the 21 patients. The only parameter studied that showed a positive correlation with a successful outcome to SNM was the age of the patient, with a higher success rate in younger males (median age 37 years [p = 0.025]). There was no other significant finding when looking at other parameters studied. Stage-2 was carried out in 13 out of 14 successful stage-1 patients. SNM restored complete voiding or improved bladder emptying in all patients implanted with a battery, and this was sustained until the battery needed to be replaced with a mean follow up of 34 ± 23.7 months except in two cases that had removal after traumatic accidents.

CONCLUSION:

Stage-1 SNM was successful in 66.7% of male patients with CUR. Once stage-2 was performed, successful voiding was maintained until the battery needed to be replaced. SNM success was better in men under a median age of 43 years. Further studies are encouraged to study this group of patients.