title: A novel technique for the intraoperative monitoring of detrusor activity in intradural lesions of the cauda equina. Technical note.
abstract: BACKGROUND
  Intradural pathology in the region of the cauda equina is uncommon and generally comes to attention secondary to pain or neurologic deficit. A number of surgeons choose to excise these lesions under EMG monitoring of the nerve roots supplying the lower extremity muscles, anal sphincter, and detrusor muscle. In this article, the authors describe a detrusor muscle monitoring technique that has been found to be simple, reliable, and cost-effective in the management of intradural pathology of the cauda equina.
  
  
  METHODS
  Fourteen consecutive patients with tumors of the cauda equina who underwent surgical management performed using the standard Foley catheter monitoring technique were included in this study and their outcomes analyzed.
  
  
  RESULTS
  In 86% of patients, a gross total resection was achieved. Subtotal resections were performed in 2 patients because of involvement of critical nerve roots. In all cases, the nerve roots supplying the detrusor muscle were successfully identified using this technique. No patient suffered a clinically apparent decline in bladder function during the postoperative period.
  
  
  CONCLUSIONS
  The standard Foley catheter detrusor monitoring technique is a simple, reliable, and cost-effective method to identify and prevent injury to the sacral nerve roots innervating the urinary bladder during intradural exploration of the cauda equina.
authors.affiliation: Department of Neurological Surgery, George Washington University School of Medicine, Washington, DC 20037, USA. jammerm@gwu.edu
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Ammerman
authors.forename: P Ben
authors.initials: PB
authors.lastname: Kerr
authors.forename: S Taylor
authors.initials: ST
authors.lastname: Jarrell
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Caputy
mesh_terms: D000328:Adult; D002420:Cauda Equina; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D009130:Muscle, Smooth / Q000503:physiopathology*; D010524:Peripheral Nervous System Neoplasms / Q000503:physiopathology / Q000601:surgery*; D001743:Urinary Bladder / Q000503:physiopathology; D014546:Urinary Catheterization