THE CORRELATION BETWEEN PROSTATE VOLUME, TRANSITION ZONE VOLUME, TRANSITION ZONE INDEX AND CLINICAL AND URODYNAMIC INVESTIGATIONS IN PATIENTS WITH LOWER URINARY-TRACT SYMPTOMS

Objective To determine if, in patients with lower urinary tract sympto ms (LUTS), measurement of the transition zone (TZ) of the prostate by transrectal ultrasonography (TRUS) and the ratio between the TZ volume and total prostate volume (TZ index) correlates better with clinical and urodynamic investigations than total prostate volume alone, Patien ts and methods In total, 150 consecutive patients with LUTS underwent a standardized screening programme including the International Prostat e Symptom Sore (IPSS), a physical examination, TRUS of the prostate an d urodynamic investigations with pressure-now studies, The total prost ate volume and TZ volume were assessed from TRUS using the ellipsoid f ormula, Spearman's rank correlation coefficients were calculated betwe en different prostate volume measurements and specific symptomatic and urodynamic variables, Results The relationships between specific IPSS symptoms, symptom scores and the prostate volume measurements were no t statistically significant except for one domain, nocturia, that appe ared to be statistically significantly correlated with the TZ index (r = 0.25). The correlations for free flow, pressure-flow variables and prostate volume measurements were stronger, but only moderate at best. The highest correlations were between TZ volume and the linear passiv e urethral resistance obstruction category, urethral resistance factor and detrusor pressure at maximum flow (r=0.43, 0.44 and 0.40, respect ively), The differences between the correlations of prostate volume an d TZ index and these variables were small (r=0.39, 0.38 and 0.37, resp ectively for prostate volume and r=0.38, 0.40 and 0.33 respectively fo r TZ index), Conclusions There were very small differences between the correlations of total prostate volume, TZ volume and TZ index, and cl inical and pressure-now variables, In the assessment of the last two, the estimation of the total prostate volume by TRUS was a reasonable w ay to obtain the required information about prostate size and measurin g TZ volume and calculating TZ index was of limited additional value. Symptoms and bladder outlet obstruction were mainly determined by othe r factors than the prostate and, specifically, TZ volume, As earlier s tudies have indicated that including pressure-flow data in the pre-ope rative evaluation and selection of patients for interventional therapi es map improve the overall clinical results, we think that prostate vo lume, TZ volume or symptoms alone should not be used as the main indic ation for deciding on the appropriate invasive treatment options.