OBJECTIVETo analyze the correlation between the size of prostatic middle lobe hyperplasia and the degree of bladder outlet obstruction (BOO) in patients with benign prostatic hyperplasia (BPH).

METHODSThis study included 131 BPH patients who presented with dysuria between May 2008 and June 2010. The prostate volume and intravesical prostatic protrusion (IPP) were measured by transabdominal ultrasound, Qmax and detrusor pressure at Qmax (P(det@ Qmax)) detected by urodynamic examination, the obstruction degree and detrusor contractility judged using the LinPURR Figure, and the AG value calculated (AG = P(det@ Qmax) -2Qmax). The degrees of BOO were compared between different groups of IPP by variance analysis, and the prostate volume, IPP and AG values underwent Bivariate correlation analysis.

RESULTSIPP was highly positively correlated with BOO when it was > 10 mm (r = 0.821, P < 0.01), while PV and BOO had a lower correlation (r = 0.475, P < 0.01). There was also a high positive correlation between IPP and P(det@ Qmax) (r = 0.865, P < 0.01).

CONCLUSIONA close correlation exists between prostatic middle lobe hyperplasia and BOO, and evaluating IPP by ultrasound is a reliable method to determine the degree of BOO.