Validation of Pressure Measuring Technique for Uroflowmetry

Uroflowmetry is a non-invasive clinical test useful for screening benign prostatic hyperplasia(BPH) common in the aged men. The standard way to obtain the urinary flow rate is to continuously measure the urine weight proportional to volume over time. The present study proposed an alternative technique measuring pressure to overcome noise problems present in the standard weight measurement. Experiments were performed to simultaneously acquire both weight and pressure changes during urination in 9 normal men. Noise components were separated from volume signals converted from both weight and pressure signals. Signal-to-noise ratio was defined as the ratio of the signal to noise power in volume changes, which was 8.5 times larger in the pressure measuring technique, implying that cleaner signal could be obtained, more immune to noisy environments. When four important diagnostic parameters were estimated, excellent correlation coefficients higher than 0.99 were resulted with mean relative errors less than 5%. Therefore, the present pressure measurement seemed valid as an alternative technique for uroflowmetry.