title: Circumferential urinary sphincter surface electromyography: A novel diagnostic method for intrinsic sphincter deficiency.
abstract: OBJECTIVE
  The diagnosis of intrinsic sphincter deficiency (ISD) in patients with stress urinary incontinence (SUI) is not well established. We explored the possibility of applying a new tool: minimally invasive circumferential sphincter surface electromyography (CSS-EMG) to assess the muscular integrity of the urethral sphincter in patients with SUI/ISD.
  
  
  METHODS
  CSS-EMG of the urethral sphincter and urodynamic studies were performed in 44 women with SUI. A urethral pressure profile (UPP) was measured in four directions. Maximal urethral closure pressure (MUCP) <40 cm/H2 O or the presence of SUI without urethral hypermobility was used to define ISD.
  
  
  RESULTS
  Twenty-one patients had urodynamic SUI, 23 had no SUI and 12 patients had ISD. The mean average rectified value (ARV) of the motor unit action potential (MUAP), an indicator of the strength of urethral rhabdosphincter, was estimated. ARV measured in the 12 o'clock quadrant during maximal contraction was the only CSS-EMG parameter that had significant predictive value for ISD. With an increase in the 12 o'clock ARV value, the likelihood of ISD decreases (Odds Ratio 0.36 95% confidence interval 0.67-0.92). In the ROC curve with ARV measured in the 12 o'clock quadrant during maximal contraction, the explained area was 0.794 (P = 0.02); implying that ARV measured at the 12 o'clock quadrant during maximal contraction was able to predict ISD significantly.
  
  
  CONCLUSIONS
  Myogenic changes of the urethral sphincter that contribute to ISD can be assessed with CSS-EMG. This new concept for assessing the functionality of the female urethral sphincter may assist with better understanding of the pathophysiology, the diagnosis and the treatment of SUI.
authors.affiliation: Department of Urology, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Heesakkers
authors.affiliation: Department of Forensic Medicine, Netherlands Forensic Institute, The Hague, The Netherlands.
authors.forename: Reza
authors.initials: R
authors.lastname: Gerretsen
authors.affiliation: Instituto Biodonostia, Hospital Universitario Donostia, San Sebastian, Spain.
authors.forename: Ander
authors.initials: A
authors.lastname: Izeta
authors.affiliation: Department of Urology, University of Tuebingen, Tuebingen, Germany.
authors.forename: Karl-Dietrich
authors.initials: KD
authors.lastname: Sievert
authors.affiliation: Department of Urology, Radboud University Medical Centre, Nijmegen, The Netherlands.|Department of Urology, Sohag University Hospital, Sohag, Egypt.
authors.forename: Fawzy
authors.initials: F
authors.lastname: Farag
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D003950:Diagnostic Techniques, Urological / Q000295:instrumentation; D004576:Electromyography / Q000295:instrumentation; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D009119:Muscle Contraction; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011312:Pressure; D012372:ROC Curve; D014521:Urethra / Q000503:physiopathology*; D014550:Urinary Incontinence, Stress / Q000175:diagnosis* / Q000503:physiopathology; D014563:Urodynamics; D055815:Young Adult
keywords: circumferential surface electromyography; stress urinary incontinence; urinary sphincter