title: Urodynamic evaluation of patients with lower urinary tract symptoms and small prostate volume.
abstract: BACKGROUND
  The relevance of prostate size in the pathophysiology of lower urinary tract symptoms (LUTS) is controversial. We evaluated the urodynamic findings in patients with LUTS and small prostate volumes.
  
  
  METHODS
  84 patients aged >or=50 years with LUTS and prostates <40 ml were evaluated. All had an International Prostate Symptom Score (IPSS) >or=8. Average age was 62.0 +/- 8.1 years. We evaluated the impact of bladder outlet obstruction (BOO) and detrusor overactivity (DO) on the voiding symptoms and urodynamic findings.
  
  
  RESULTS
  Mean prostate volume was 29.2 +/- 7.2 ml and mean IPSS was 13.5 +/- 4.6. BOO was the main finding, affecting 42 (50.0%) patients, followed by detrusor underactivity (DU) in 41 (48.8%) and DO in 28 (33.3%) patients. Patients without BOO were significantly older than the obstructed (64.0 +/- 8.8 and 60.1 +/- 6.9 years, respectively; p = 0.026) and had an increased prevalence of DU (76.2 and 21.4%, respectively; p < 0.001). Comparison of patients with and without DO showed reduced bladder capacity and compliance in the DO group (p < 0.001). No other comparisons were significant.
  
  
  CONCLUSIONS
  Half of the patients with LUTS and small prostates are not obstructed and may have DO or decreased detrusor contractility as the basis for their voiding symptoms. Our results emphasize the value of urodynamics in this population, especially when invasive treatments are being considered.
authors.affiliation: Division of Urology, University of São Paulo School of Medicine, São Paulo, Brazil. crismgomes@uol.com.br
authors.forename: Cristiano M
authors.initials: CM
authors.lastname: Gomes
authors.forename: Ricardo V
authors.initials: RV
authors.lastname: Nunes
authors.forename: Rogerio M
authors.initials: RM
authors.lastname: Araújo
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Sacomani
authors.forename: Flavio E
authors.initials: FE
authors.lastname: Trigo-Rocha
authors.forename: Homero
authors.initials: H
authors.lastname: Bruschini
authors.forename: Miguel
authors.initials: M
authors.lastname: Srougi