Newer contrast agents for urography.

New low-osmolality ratio-3 contrast media have been shown to have less toxicity than currently used contrast media. In intravenous excretory urography, these agents give significantly higher urinary iodine concentrations, produce less diuresis, and are better tolerated by patients because of fewer unpleasant side effects. These newer low-osmolality contrast media have significant advantages in intravenous urography.