Critical review of the uroflowmetry

Uroflowmetry is the measurement of a urinary flow rate by using the flow meter. A urine flow rate is the volume of urine (millilitres) expelled from the bladder via the urethra per unit of time (second). It is expressed in ml/s.(1) Urine flow curve is the plot of velocity of the voided urine against time. The urine stream is affected by voiding pressure (detrusor power) and bladder outlet resistance. Therefore, uroflowmetry evaluates the interaction of the urinary bladder expelling strength and bladder outlet resistance. This is the initial, non-invasive urodynamic investigation for evaluation of patients with lower urinary tract symptoms (LUTS). Although, it is very simple and widely used urodynamic test, the results are nonspecific and required caution interpretations. In the next few pages we will review some aspects of this test, i.e. brief history, equipment, indications, procedure itself and interpretation of the results.