MDCT urography with high-volume low-concentration i.v. contrast material, peroral hydration, i.v. furosemide, and i.v. saline: qualitative and quantitative assessment in 100 consecutive patients.

OBJECTIVE

The purpose of this study is to qualitatively and quantitatively assess MDCT urography performed with a high volume of low-concentration (240 mg I/mL) i.v. contrast agent supplemented with peroral hydration, i.v. furosemide, and i.v. saline.

MATERIALS AND METHODS

This retrospective evaluation of 100 consecutive normal MDCT urograms was performed for clinical indication of hematuria; patients (76 men and 24 women) were 27-90 years old (mean [± SD] age, 60 ± 15 years). Three radiologists evaluated the degree of opacification across six urinary tract segments (for a total of 1200 measurements per radiologist) on a 4-point scale (0-3). One radiologist measured the maximum short-axis diameter of the proximal, mid, and distal ureters in each patient. Mean opacification scores were calculated for each segment. Radiologist agreement was assessed by kappa coefficient and Spearman rank correlation. Ureteral diameter was correlated to degree of opacification using the Jonckheere-Terpstra trend test. A comparison with published studies using similar scoring methods was undertaken.

RESULTS

Of 1200 measured ureteral segments, a total of 24 among the three radiologists were reported as nonopacified. The mean opacification scores ranged from 2.63 ± 0.8 to 3.00 ± 0.8. Calculated kappa coefficients are indicative of substantial agreement (> 0.61). The mean maximal ureteral diameters were 5.44 ± 1.10, 6.32 ± 1.54, and 5.32 ± 1.55 mm for the proximal, mid, and distal ureters, respectively. For all three radiologists, the mean opacification scores increased as distention increased. The Spearman correlation and corresponding p value (p < 0.001) for the association between the distention with the opacification scores show significant correlation. The opacification scores and ureteral distention exceeded published results.

CONCLUSION

An MDCT urography technique using high-volume low-concentration i.v. contrast, oral and i.v. hydration, and i.v. diuretic reliably optimizes urinary tract opacification and distention. A positive correlation was found between ureteral distention and opacification.