uroflowmeter

A uroflowmeter is a noninvasive medical device used to measure the rate and pattern of urine flow during voiding. It is commonly used in urology to evaluate lower urinary tract symptoms and to assess suspected bladder outlet obstruction, detrusor underactivity, or other voiding dysfunction. A patient voids into a calibrated collection system that integrates sensors and a recording device. The device produces a flow–time curve, from which several quantitative parameters are derived, including peak flow rate (Qmax), average flow rate (Qmean), voided volume, and voiding time. The shape of the flow curve, such as a bell-shaped curve or plateau, can aid interpretation. Some uroflowmeters also report time to peak flow and can indicate partial obstruction or poor detrusor contractility when used in conjunction with clinical findings.

There are several designs: simple funnel-based systems that collect urine into a graduated container attached to a flow sensor; weight-based or pressure-sensor devices that translate fluid passage into flow rate; and integrated systems in some toilet or bedpan setups for convenient testing. Modern devices may store data digitally and allow repeated measurements to assess variability.

Limitations include dependence on adequate voiding into the device, patient effort, and day-to-day variability. Uroflowmetry is typically part of a broader urological assessment, often complemented by post-void residual measurement and, if needed, invasive urodynamic testing.