title: Sacral root neuromodulation in idiopathic nonobstructive chronic urinary retention.
abstract: OBJECTIVE
  Sacral root neuromodulation is becoming a superior alternative to the standard treatment of idiopathic nonobstructive urinary retention. We report results in 20 successive patients who underwent sacral foramen implantation to restore bladder function.
  
  
  METHODS
  After an initial, thorough baseline assessment 20 patients 19.43 to 55.66 years old with idiopathic nonobstructive urinary retention underwent percutaneous nerve evaluation. Response was assessed by a detailed voiding diary. Responders underwent implantation with an S3 foramen implant, and were followed 1, 3 and 6 months postoperatively, and every 6 months thereafter.
  
  
  RESULTS
  Sacral root neuromodulation restored voiding capability in these patients. Bladders were emptied with minimal post-void residual urine, which decreased from 78.3 to 5.5 to 10.2% of the total voided volume from baseline to postoperative followup. These results were reflected in uroflowmetry and pressure-flow studies, which were almost normal after implantation. Furthermore, the urinary tract infection rate decreased significantly and associated pelvic pain improved substantially. The Beck depression inventory and SF-36 quality of life questionnaire indicated some improvement but reached significance in only 1 item. In addition, cystometrography showed no significant difference after 6 months of implantation compared with baseline values. Complications were minimal and within expectations.
  
  
  CONCLUSIONS
  Sacral root neuromodulation is an appealing, successful modality for nonobstructive urinary retention. Only patients who have a good response to percutaneous nerve evaluation are candidates for implantation. The high efficacy in patients who undergo implantation, relative simplicity of the procedure and low complication rate make this a treatment breakthrough in this difficult group.
authors.affiliation: Division of Urology, Toronto Hospital, University of Toronto, Ontario, Canada.
authors.forename: H S
authors.initials: HS
authors.lastname: Shaker
authors.forename: M
authors.initials: M
authors.lastname: Hassouna
mesh_terms: D000328:Adult; D002908:Chronic Disease; D004599:Electric Stimulation Therapy; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants; D013126:Spinal Nerve Roots; D016896:Treatment Outcome; D016055:Urinary Retention / Q000503:physiopathology / Q000628:therapy*; D014563:Urodynamics