Pressure Flow Studies I

Abstract

It was always believed and stated in the urological literature that ‘dilated’ urinary tracts were obstructed. Indeed, until the significance of vesicoureteric reflux was appreciated the words dilated and obstructed were almost synonymous. This attitude is reflected in the early classifications of megaureters where two types were described— refluxing and obstructed. It was Shopfner (1966) who suggested that perhaps not all wide or dilated systems were truly obstructed, but it has taken many more years for this message to be appreciated. The first proof that he was correct was provided by Backlund and Reuterskiöld (1969), who were able to demonstrate low pressures on perfusion in some dilated systems showing the absence of obstruction.