The Predictors of Acute Urinary Retention in Patients with Benign Prostatic Hyperplasia / 대한비뇨기과학회지

PURPOSE: Acute urinary retention is one of the most severe complications in patients with benign prostatic hyperplasia (BPH). We investigated the efficacy of age, International Prostatic Symptom Score (I-PSS), quality of life (QOL) score and various parameters obtained by transrectal ultrasonography (TRUS) as predictors of acute urinary retention. MATERIALS AND METHODS: Of 153 patients with BPH, who underwent transurethral resection of the prostate, 72 were treated due to acute urinary retention (retention group) and 81 due to lower urinary tract symptoms (symptomatic group). TRUS was used to calculate the total prostate (TP) and transitional zone (TZ) volumes, the transitional zone index (TZ index=TZ volume/TP volume) and the elongation ratio (ER=the ratio of the maximal anteroposterior to transverse diameter of the prostate). To compare the usefulness of various parameters between the retention and symptomatic groups, the area under the receiver-operating characteristic (ROC) curve was calculated for each parameter. RESULTS: There were significant differences in the TP and TZ volumes, the TZ index and the elongation ratio between both groups, but no significant differences in age, I-PSS or QOL score. In the retention group, the most effective cutoff values were 40cc, 20cc, 0.55 and 0.75 for the TP volume, the TZ volume, the TZ index and the elongation ratio, respectively. The area under the ROC curves were 0.894, 0871, 0843 and 0771 for the TZ index, the elongation ratio, the TZ volume and the TP volume, respectively. CONCLUSIONS: The TP and TZ volumes, the TZ index, and the elongation ratio are useful predictors of acute urinary retention in patients with BPH. The TZ index is the most useful predictor, and may be a useful parameter in selecting the treatment for BPH.

Transitional Zone Index: a Predictor of Acute Urinary Retention in Patients with Benign Prostatic Hyperplasia / 대한비뇨기과학회지

PURPOSE: To investigate the efficacy of age, International Prostate Symptom Score(I-PSS), quality of life(QOL) score, various parameters obtained by transrectal ultrasonography(TRUS) as predictors of the onset of acute urinary retention in patients with benign prostatic hyperplasia(BPH). MATERIALS AND METHODS: From January 1996 to December 1997, 101 men(mean age 70years, range 52-92) with symptoms of BPH were enrolled in this study. Among them, 36 patients had suffered from acute urinary retention. TRUS was used to calculate the total prostate(TP) volume, the transitional zone(TZ) volume, the transitional zone index(TZ index=TZ volume/TP volume). To compare the usefulness of various indices, the area under the receiver-operator characteristic(ROC) curve was calculated for each index. RESULTS: There were significant differences in age, TP volume, TZ volume, TZ index between patients with and without acute urinary retention, but no significant differences in I-PSS and QOL score. In patients with acute urinary retention, the area under the ROC curve was 0.911 for the TZ index, 0.892 for the TZ volume, 0.769 for the TP volume and 0.660 for the age. CONCLUSIONS: The TZ index is a useful predictor of acute urinary retention in patients with BPH and may be a useful parameter for decision of surgical intervention.