Utilities of Intravesical Prostatic Protrusion and Peak Flow Rate Measurements as Clinical Tools in Diagnosis of Bladder Outlet Obstruction in A Community Setting

Abstract

Background: Clinical diagnosis of cause of bladder outlet obstruction (BOO) is often difficult and decision on who and when to treat intriguing.  Pressure flow studies are the main stay diagnostic tool but they are cumbersome, not readily available and expensive.  Use of simpler modalities like ultrasound determination of intravesical prostatic protrusion (IPP) and uroflow-metric measurement of Peak flow rate (PFR), if found to correlate with clinical index of BOO such as International Prostate Symptom Score (IPSS) could make diagnosis of BOO easier in and outside the hospital setting. Aim: To determine if IPP measured with transabdominal USS and PFR measured with uroflow-meter correlate with International Prostate Symptom Score (IPSS) which is a clinical marker of bladder outlet obstruction. Methods: In a community setting we evaluated males 40years and above who were not known to have history of lower urinary tract symptoms. Using IPSS questionnaire we obtained IPSS score for each participant. We determined the IPP when bladder was fully distended using 3.5MHx Mindray DP2200 transabdominal ultrasound. We asked each participant to void into the uroflow-meter machine and recorded the PFR. Using Spearman’s correlation coefficient, we corelated IPSS with IPP and PFR. Statistical significance was determined at p value <0.05. Results: Pearsons correlation coefficient showed IPSS scores exhibited a statistically significant negative correlation with peak flow rate [r = -0.257, p = 0.001] and significant positive correlation with IPP [r=0.22, p = 0.030] There was negative relationship between IPP and peak flow rate but this was not significant [r = -0.15, p = 0.124]. Conclusion: USS measurement of IPP and uroflow measurement of PFR are useful tools in assessing BOO especially in settings where pressure flow studies are not readily available.