title: Does defective volume sensation contribute to detrusor underactivity?
abstract: OBJECTIVE
  The urodynamic finding of detrusor underactivity (DU) in neurologically intact unobstructed patients may relate to impaired volume sensations rather than detrusor contractile defects. We hypothesized that DU patients would demonstrate higher volumes but similar wall stress at sensation thresholds, and similar voiding contractility, compared to other groups.
  
  
  METHODS
  Chart review of urodynamic studies in neurologically normal, nonobstructed symptomatic patients. Urodynamic studies having the primary findings of DU, stress urinary incontinence (SUI), detrusor overactivity (DO), and increased sensations without detrusor overactivity (IS) were abstracted. Age, gender, and pressure/volume data associated with sensations and voiding parameters were collected. Wall stress at sensations was calculated. Urodynamic variables at standard sensations and progression across standard sensations were compared among the four groups.
  
  
  RESULTS
  Fifty-one urodynamic studies were analyzed for comparison. Mean age did not differ between groups. The DU group was predominantly male versus the other groups. DU, SUI, and DO had higher volume thresholds for strong desire than did IS. DU and DO demonstrated higher wall stress at strong desire than did IS and SUI. Watts factor was not significantly different between groups, however, DU had a smaller voided volumes and a higher post-void residuals.
  
  
  CONCLUSIONS
  Increased volume and wall stress at strong desire, and similar contractility but the smaller voided volumes and elevated PVRs in DU suggest that diminished central sensitivity to volume afferent activity contributes to DU in nonobstructed, non-neurogenic symptomatic patients.
authors.affiliation: Department of Surgery, University of Connecticut Health Center, Farmington, Connecticut.
authors.forename: Phillip P
authors.initials: PP
authors.lastname: Smith
authors.affiliation: Department of Urology, Children's Hospital Colorado, Aurora, Colorado.
authors.forename: David J
authors.initials: DJ
authors.lastname: Chalmers
authors.affiliation: Quinnipiac University School of Medicine, North Haven Campus, North Haven, Connecticut.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Feinn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000503:physiopathology*; D012677:Sensation / Q000502:physiology*; D001743:Urinary Bladder / Q000503:physiopathology*; D001745:Urinary Bladder Diseases / Q000503:physiopathology*; D053201:Urinary Bladder, Overactive / Q000503:physiopathology; D014549:Urinary Incontinence / Q000503:physiopathology; D014563:Urodynamics / Q000502:physiology*; D055815:Young Adult
keywords: detrusor underactivity; urodynamics