Comparison between prostate volume and intravesical prostatic protrusion in detecting bladder outlet obstruction due to benign prostatic hyperplasia

Abstract

The objectives of this study were to determine and compare the correlation of intravesical prostatic protrusion (IPP) and prostate volume (PV) with bladder outlet obstruction (BOO). This study was conducted in the department of urology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh, between July 2009 to September 2010. Fifty benign prostatic hyperplasia (BPH) patients were included in the study. Their evaluation consisted of history along with International Prostate Symptoms Score (IPSS), digital rectal examination (DRE), transabdominal ultrasonography to measure prostate volume, intravesical prostatic protrusion & post voidal residual (PVR) urine and pressure-flow studies to detect bladder outflow obstruction (BOO). Statistical analysis included Unpaired ‘t’ test, Chisquare test and Spearman’s Rank correlation test. Receiver Operator Characteristic (ROC) curves were used to compare the correlation of PV and IPP with BOO. Mean prostate volume was significantly larger in bladder outlet obstructed patients (P<0.05). Mean IPP was significantly greater in obstructed patients (P<0.001). Area under ROC curve was 0.700 for PV and 0.821 for IPP. Prostate volume & intravesical prostatic protrusion measured through transabdominal ultrasonography are noninvasive and accessible method that significantly correlates with bladder outlet obstruction in patients with benign prostatic hyperplasia and the correlation of IPP is much more stronger than that of prostate volume. Introduction Benign prostatic hyperplasia (BPH) is one of the most common diseases in elderly men. The prevalence of histological BPH increases with age and appears in approximately 40% of men aged 50- 60 years and in approximately 90% of men aged more than 80 years1. Benign prostatic hyperplasia may lead to prostatic enlargement, bladder outlet obstruction (BOO) and lower urinary tract symptoms (LUTS). But the symptoms and obstruction do not entirely depend on prostate’s size. In contrast, intravesical prostatic protrusion (IPP) has been found to correlate with BOO2. IPP is a morphological change due to overgrowth of prostatic median and lateral lobes into the bladder and may lead to diskinetic movement of bladder during voiding. This IPP would cause more obstruction than if there were no protrusion and just enlargement of lateral lobes, as the strong bladder contraction could force open a channel between the lobes3. Several studies have previously demonstrated that the ultrasonographic measurement of IPP is able to detect BOO in BPH patients quickly and non-invasively4. This study was designed to diagnose BOO through non-invasive methods and aimed to define the correlationDOI: http://dx.doi.org/10.3329/bmrcb.v38i1.10446  Bangladesh Med Res Counc Bull 2012; 38: 14-17