title: Urodynamic pressure flow studies can predict the clinical outcome after transurethral prostatic resection.
abstract: OBJECTIVE
  We evaluate whether urodynamic evaluation can determine preoperatively the clinical prognosis of patients treated with transurethral prostatic resection as measured by urinary symptom score and quality of life index.
  
  
  METHODS
  A total of 253 patients who previously elected transurethral prostatic resection based on clinical symptoms completed the American Urological Association symptom score and quality of life index, and underwent urodynamic evaluation before and after operation. The patients were divided into 7 groups in accordance with detrusor pressure at maximum urinary flow rate. The preoperative and postoperative symptom score and quality of life index were analyzed in each group.
  
  
  RESULTS
  Of the patients 42% were not obstructed and could not be distinguished from those who were obstructed preoperatively based on total urinary symptoms (p = 0.95) or subjective impression measured by the quality of life index (p = 0.96). The entire obstructed group demonstrated marked improvement compared to the nonobstructed group (p = 0.018). Analysis of severity also revealed a clear relationship with clinical outcome and subjective satisfaction with obstruction grade, that is the more severely obstructed cases had greater clinical benefit compared to those with little or no obstruction. Furthermore, the nonobstructed subjects did not show any clinical or subjective improvement after transurethral prostatic resection (p = 0.24).
  
  
  CONCLUSIONS
  Urodynamic studies provide great predictive value of clinical improvement after prostatic relief but they also properly predict the poor clinical results in nonobstructed patients.
authors.affiliation: Department of Urology, Hospital das Clínicas of Univesity of São Paulo, São Paulo, Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Rodrigues
authors.forename: A M
authors.initials: AM
authors.lastname: Lucon
authors.forename: G C
authors.initials: GC
authors.lastname: Freire
authors.forename: S
authors.initials: S
authors.lastname: Arap
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011470:Prostatic Hyperplasia / Q000503:physiopathology* / Q000601:surgery*; D020728:Transurethral Resection of Prostate; D016896:Treatment Outcome; D014563:Urodynamics