title: Stimulation of the Neurovascular Bundle Results in Rhabdosphincter Contraction in a Proportion of Men Undergoing Radical Prostatectomy.
abstract: OBJECTIVE
  To use nerve conduction studies to clarify the functional innervation of the male urethral rhabdosphincter (RS). In particular, to test the hypothesis that in some men, fibers of the neurovascular bundle supply the RS. These fibers may be at risk during radical prostatectomy.
  
  
  METHODS
  Men undergoing robot-assisted radical prostatectomy for clinically localized prostate cancer were included. Men with a history of pelvic surgery and/or radiation and/or trauma, obesity, or neurological diseases were excluded. Nerve conduction studies were performed before and after prostate removal. The St. Mark's pudendal electrode was used for pudendal (control) stimulation. The ProPep Nerve-Monitoring System (ProPep Surgical, Austin, TX) was used to stimulate the neurovascular bundle at the level of the prostate base, mid, and apex. ProPep needle electrodes inserted into the RS were used to measure evoked compound motor action potential response. Results were only included if a valid pudendal control was elicited.
  
  
  RESULTS
  Seventeen men in total underwent investigation. Valid measurements were obtained after initial quality control in seven. In two cases, evidence of sphincteric activation was observed, providing evidence to support neurovascular bundle innervation of the RS. In the other five patients, no intrapelvic nerve supply was demonstrated.
  
  
  CONCLUSIONS
  Somatic nerve supply to the RS is variable. Direct intrapelvic supply to the RS may exist in some men. This may be one explanation as to why some patients unexpectedly develop severe urinary incontinence postoperatively despite technically satisfactory surgery. Further research is required to validate our findings.
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia. Electronic address: fairleighr@gmail.com.
authors.forename: Fairleigh
authors.initials: F
authors.lastname: Reeves
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Wouter
authors.initials: W
authors.lastname: Everaerts
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia; Division of Cancer Surgery, Peter MacCallum Cancer Centre, University of Melbourne, Melbourne, Australia.
authors.forename: Declan G
authors.initials: DG
authors.lastname: Murphy
authors.affiliation: Department of Neurology, The Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Lynette
authors.initials: L
authors.lastname: Kiers
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Justin
authors.initials: J
authors.lastname: Peters
authors.affiliation: Department of Anaesthesia, St Vincent's Hospital, Melbourne, Australia.
authors.forename: Tim
authors.initials: T
authors.lastname: Costello
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Niall M
authors.initials: NM
authors.lastname: Corcoran
authors.affiliation: Department of Urology and Surgery, University of Melbourne, The Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Costello
mesh_terms: D001341:Autonomic Nervous System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D011468:Prostatectomy / Q000009:adverse effects* / Q000379:methods; D011471:Prostatic Neoplasms / Q000628:therapy*; D012371:Robotics / Q000379:methods; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*; D001743:Urinary Bladder / Q000294:innervation*; D014549:Urinary Incontinence / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*