Use of additives to contrast media to improve imaging in plain film and computed tomography urography

RATIONALE AND OBJECTIVES: To investigate the effects of additives to iodinated radiograph contrast agents on image quality in plain film and CT urography. MATERIALS AND METHODS: Urea (52 mg/mL), iloprost (10, 20, 50, and 100 ng/mL), nifedipine (0.02 mg/mL), papaverine (0.625 mg/mL) and sodium nitroprusside (0.05 microg/mL) were added to commercial iopromide (300 mg/mL) and iotrolan preparations (280 mg/mL) and plain film urograms were obtained at different time points after contrast injection in rabbits and dogs at iodine doses of 300 or 600 mg/kg body weight. The experiments were repeated in rabbits using CT imaging and iopromide or iotrolan plus urea (52 mg/mL) or iloprost (20 ng/mL) and iodine doses of 50 mg/kg body weight. RESULTS: Urea and iloprost at low concentrations (10 and 20 ng/mL) increased image quality both in plain film and in CT urography. Iloprost at high concentrations (50 and 100 ng/mL), nifedipine, papaverine and sodium nitroprusside decreased image quality. An increase in image quality was accompanied by faster renal elimination of the contrast agent. CONCLUSION: Image quality in plain film and CT urography might be improved by additives to the contrast medium. More data, particularly on dose-response relationships are needed.