Unequal doses of ioversol versus diatrizoate for urography

A randomized, double-blind clinical trial was performed to compare a higher dose of conventional ionic contrast media (diatrizoate) with a lower dose of a new, nonionic contrast material (ioversol) for excretory urography (EU). One hundred twenty patients were randomized to receive either 100 ml of diatrizoate (Renografin-60) or 75 ml of ioversol (Optiray-320). Despite the lower iodine dose, the use of ioversol resulted in significantly better opacification of the calyces, renal pelves, and ureters. There was no significant difference in renal parenchymal opacification, opacification of the urinary bladder, or distention of the collecting system. We conclude that high-quality EU can be performed with a lower iodine dose using ioversol.