Objective: The present study was conducted to determine the correlation between the urinary symptoms and lower urinary tract dynamics in patients with prostatism.
Methods: 105 males with prostatism (mean 66.19 years) were evaluated clinically, urodynamically and radiologically by PURR (passive urethral resistance ratio) determination.
Results: The intensity of the irritative symptoms was slightly higher (21%) when bladder instability was associated. The obstructive symptoms were associated with diminished urinary flow rate and could be observed in bladder outlet obstruction (81%) or diminished bladder contractility (79%). Both conditions were found in 49% of the cases. The postvoiding urine depended on diminished bladder contractility (37%), but not on bladder outlet obstruction. Bladder instability did not depend on obstruction, although 88% of the patients with unstable bladder were obstructed. Compressive obstruction was associated with a lesser degree of diminished contractility (55%) than the other forms of obstruction. Prostatism was associated with diminished contractility without bladder outlet obstruction in 15% of the cases. The irregular bladder was more frequent in bladder outlet obstruction (92%) and bladder diverticula were more frequent in bladder instability (36%). In all the cases with compression and lengthening of the prostatic urethra, the diagnosis was compressive obstruction. In all the cases with segmental, diminished urethral diameter, the diagnosis was obstruction, although only 30% were diagnosed as constrictive compression. No pathological urethral changes were demonstrable on cystourethrography in 33% of the cases with obstruction.
Conclusions: Urinary symptoms correlate poorly with lower urinary tract dynamics. PURR determination is a very reliable method of diagnosis in urinary obstruction, for both segmentally diminished and more extensive involvement (elongation and compression of the prostatic urethra) of the urethral lumen.