title: Urethral and bladder current perception thresholds: normative data in women.
abstract: OBJECTIVE
  Given increased evidence of sensory dysfunction in lower urinary tract pathology, we determined normative current perception threshold values in the lower urinary tract of asymptomatic women.
  
  
  METHODS
  After receiving institutional review board approval women without lower urinary tract symptoms underwent current perception threshold testing of the urethra and bladder using a Neurometer constant current stimulator. Current perception threshold values were determined at 3 frequencies, including 2,000 Hz (corresponding to A-beta fibers), 250 Hz (corresponding to A-delta fibers) and 5 Hz (corresponding to C fibers).
  
  
  RESULTS
  A total of 48 women with a mean age of 38 years (range 23 to 67) underwent current perception threshold testing. Normative values were established for the urethra and bladder at 2,000, 250 and 5 Hz. Median urethral current perception thresholds at 2,000, 250 and 5 Hz were 1.2 (IQR 0.76-1.5), 0.45 (IQR 0.33-0.56) and 0.11 mA (IQR 0.07-0.24), respectively. Median bladder current perception thresholds at 2,000, 250 and 5 Hz were 4.1 (IQR 2.0-6.3), 2.3 (IQR 0.87-5.5) and 1.4 mA (IQR 0.22-2.9), respectively. Urethral and bladder current perception thresholds increased significantly with subject age at all 3 frequencies (p<0.0005). Prior pelvic surgery was associated with an increased bladder current perception threshold at all 3 frequencies (p<0.005) but not with the urethral current perception threshold.
  
  
  CONCLUSIONS
  We report urethral and bladder current perception thresholds for a large sample of asymptomatic women. These reference values may help elucidate changes in afferent nerve function in women with lower urinary tract dysfunction.
authors.affiliation: Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Urology, Loyola University Medical Center, Chicago, Illinois, USA.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Kenton
authors.forename: Jennifer
authors.initials: J
authors.lastname: Simmons
authors.forename: Mary Pat
authors.initials: MP
authors.lastname: FitzGerald
authors.forename: Lior
authors.initials: L
authors.lastname: Lowenstein
authors.forename: Linda
authors.initials: L
authors.lastname: Brubaker
mesh_terms: D000328:Adult; D000368:Aged; D004558:Electric Stimulation; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006801:Humans; D008875:Middle Aged; D012016:Reference Values; D012684:Sensory Thresholds / Q000502:physiology*; D014521:Urethra / Q000502:physiology*; D001743:Urinary Bladder / Q000502:physiology*