ABSTRACT
PURPOSE: To optimize the MDCT urogram protocol for assessment of the upper tracts. To assess the value of furosemide injection. MATERIALS AND METHODS: Prospective study comparing excretory phase imaging at 450 seconds in 67 patients assigned to 3 groups: a group without furosemide (f=0), a group with 20 mg furosemide (f=20), and a group with 10 mg furosemide (f=10). 3D MIP images were generated. Two experienced radiologists blinded to protocol specifications analyzed the quality of opacification the upper tracts, divided in 8 segments and urine density at the renal pelvis. RESULTS: The injection of 20 mg of furosemide significantly improved the opacification of the upper tracts with complete or near complete opacification in 82.6% of cases compared to 43.5% and 19% for the F=10 and f=0 groups respectively. Density measurements were 5 times less for the f=20 and f=10 groups compared to the f=0 group. CONCLUSION: Furosemide is useful for MDCT urography by improving upper tract opacification and filling: the reduced contrast concentration in the better distended and fully filled upper tracts improves evaluation of ureteral lumen and wall abnormalities.
