ARRS 2022 Abstracts


1876. Correlation of Incomplete Opacification on CT Urography with Ureteral Abnormalities During Retrograde Pyelogram
Authors * Denotes Presenting Author
  1. Xiaochen Liu *; University of Toledo Medical Center
  2. Sammy Droubi; University of Toledo Medical Center
  3. Saqib Ali; University of Toledo Medical Center
  4. Jacob Bieszczad; Toledo Radiological Associates; University of Toledo Medical Center
  5. Michael Walsh; Toledo Radiological Associates; University of Toledo Medical Center
Computed tomographic urography (CTU) is considered the gold standard for the detection of urinary tract disease. Multiple techniques have been reported in the literature to optimize urinary tract opacification and distention to enhance detection of genitourinary tract disease. However, due to the physiologically dynamic nature of the ureters, incomplete opacification of the ureters remains a common occurrence. Incomplete opacification on CTU has been cited as a clinical indication for follow-up cystoscopy, with retrograde pyelogram (RPG). The efficacy and utility of this procedural combination remains uncertain. The objective of this study is to retrospectively analyze the RPG findings of incompletely opacified ureters on CTU.

Materials and Methods:
A retrospective review of 300 CTU examinations was performed by two experienced body imaging radiologists identifying 142 incompletely opacified ureters. CTU was performed with varying intravenous iodine concentrations of 300, 320, and 350 mg iodine/mL. Follow-up clinical, cystoscopy, and RPG notes were reviewed to identify findings in the incompletely opacified ureters or within the bladder. Statistical analysis of the frequencies of ureteral or bladder abnormalities found during cystoscopy/RPG was performed using chi-squared test on IBM SPSS Statistic 23. Statistical significance was defined as p<0.05.

Of the 142 incompletely opacified CTUs, 0.04% (2/48) ureteral abnormalities were identified in CTU performed with 300 mg iodine/mL IV contrast. No ureteral abnormalities were found in CTU performed with 320 or 350 mg iodine/mL contrasts. The overall ureteral abnormality found during cystoscopy for incomplete opacification during CTU was 0.01% (2/142). There was no statistical significance or correlation between incomplete opacification on CTU and ureteral abnormalities on follow-up RPG. Additionally, no statistically significant correlations were found for the bladder abnormalities on cystoscopy, p>0.05.

Our study results demonstrated that there were no significant abnormalities or malignancy detected with RPG in the incompletely opacified ureters on CTU. There is no statistical significance or correlation between the incomplete ureteral opacification and ureteral abnormalities on follow up RPG. The utility of RPG following CTU for incompletely opacified ureters that are otherwise normal in appearance without dilatation is low yield for significant abnormality or malignancy. Although preliminary data for bladder abnormalities was also statistically insignificant, a more comprehensive analysis of the radiologic and clinical data is needed. This preliminary result has the potential to bring significant changes in clinical practice and is useful step toward cost-containment strategies pertinent in today’s healthcare landscape.