Prostatic zonal parameters and lower urinary tract symptoms as quantified via magnetic resonance imaging

Benign prostatic hyperplasia (BPH) is a common diagnosis among aging males; however, the relationship between prostate volume and lower urinary tract symptom (LUTS) severity is imperfect. The goal of this study was to comprehensively investigate the relationship between various prostate zone-based parameters measured using magnetic resonance imaging (MRI) and LUTS.

Data were retrospectively collected for 144 patients who underwent MRI between 2015 and 2017 at a single institution. Prostate volumes were measured on sagittal and axial T2 weighted using the prostate ellipsoid formula.

Only transition zone thickness (TZT) correlated with International Prostate Symptom Score (IPSS) (Pearson's=0.33, p=0.007). The intraprostatic protrusion (IPP) component (rho=0.261, p=0.036), transitional zone volume (TZV) (rho=0.264, p=0.034), and TZT (Pearson's correlation=0.422, p<0.001) all correlated with worsening quality of life (QoL) scores. In total, 97.9% of men had the presence of an IPP (>0 mm) and larger IPPs were found in older men with higher postvoid residual volumes. Larger peripheral zone volume (PZV) (odds ratio [OR ] 3.62, 95% confidence interval [CI] 1.07-12.30, p<0.05), TZV (OR 6.00, 95% CI 1.69-21.35, p<0.05), and TZT (OR 4.00, 95% CI 1.17-13.69, p<0.05) were predictive of developing severe LUTS ; however, IPP (p=0.122) was not.

TZV, TZT, and IPP all demonstrated a role in the evaluation of LUTS, with predictive capabilities. IPP is very common but not always clinically significant. Clarifying more precise zonal parameters and their relationship with LUTS may ultimately help clinicians guide the need for surgical intervention more precisely.