The Usefulness of Residual Urine Fraction and Maximal Flow Rate for Predicting Outcome after Transurethral Resection of Prostate in Benign Prostatic Hyperplasia

Ku, Ja Hyeon; Song, Yun Seob; Kim, Min Eui; Lee, Nam Kyu; Park, Young Ho

Abstract

PURPOSE: To investigate whether residual urine fraction can predict the outcome after transurethral resection of prostate in benign prostatic hyperplasia.
MATERIALS AND METHODS
From February 1995 to June 1999, benign prostatic hyperplasia aged 54 to 82years(mean: 65.4+/-6.7years) were examined with maximal flow rate and postvoid residual using uroflometry and ultrasonography, respectively, before and after transurethral resection of prostate. Residual urine fraction was defined as postvoid residual/pre-micturition volumex100.
RESULTS
There was a significant correlation between pre-micturition volume and postvoid residual and the variation of residual urine fraction was significantly narrower than that of postvoid residual. Residual urine fraction was inversely correlated with postoperative maximal flow rate in patients whose preoperative maximal flow rate were above 12 ml/sec.
CONCLUSIONS
Residual urine fraction is more reliable than postvoid residual. So, we suggest that residual urine fraction is more accurate index than postvoid residual in accessing of bladder emptying and may predict the treatment outcome in selected patients, if it is combined with preoperative maximal flow rate.