Urinary flow velocity as an index of male voiding function.

Urinary velocity and urinary peak flow rate developed by 463 male patients were measured before and after treatment for prostatic obstruction, stricture or prostatitis and compared to 121 documented normal males. It was shown that peak flow rate does discriminate partially between the normal and non-normal populations, but that many subjects who presented with ostensibly normal flow rates were actually obstructed when measured by peak urinary velocity. Velocity is shown to be a valuable secondary measurement in the clinic, and the flow velocity vs. flow rate diagram is demonstrated to be a good tool for classifying patients urodynamically.