[Residual fraction in the evaluation of bladder outlet obstruction resulting from benign prostatic hyperplasia].

OBJECTIVES

To study residual fraction (RF) in the bladder outlet obstruction (BOO) resulting from benign prostatic hyperplasia (BPH).

METHODS

Fifty adult outpatients with BPH were evaluated. With ultrasound and uroflowmetry, prevoid volume (PV) and postvoid residual volume (PRV) and peak flow rate (Qmax) were determined. Linear dependence analysis of RF and Qmax, PRV and Qmax were conducted.

RESULTS

The coefficient between RF and Qmax showed extremely negative correlation(r = -0.3859, P < 0.01). Also, PRV and Qmax showed significant negative correlation (r = -0.2831, P < 0.05).

CONCLUSIONS

The greater the RF, the more serious the BOO, the poorer potency of bladder. It is recommended that RF be used as a good supplement to PVR in the routine non-invasive evaluation of BOO caused by BPH.