Direct radionuclide cystography (DRC) is a safe and reliable method for the detection and follow-up of vesico-ureteral reflux (VUR). Since the first DRC was performed, during the early 60s, the method has undergone many refinements. Themanometric approach, which was first introduced in 1984, provides a correlation between the bladder pressure and VUR visualization. In this study the sources of error that may alter the results of DRC are discussed and a novel, standardized low costmanometric apparatus is suggested.