Abdom Imaging (2011)
Carmen Sebastia, Sergi Quiroga, Laura Bunesch, Rosa Boye, Rafael Salvador, Carlos Nicolau
Abstract
Purpose: To evaluate the diagnostic value of computed tomography (CT) performed immediately after excretory urography (EU) in patients with delayed renal opacifi-cation or dilated upper urinary system with nonconclu-sive diagnosis after EU. Materials and methods: CT was performed immediately after EU in 39 patients with delayed opacification or dilated upper urinary system of unknown cause, without additional intravenous contrast administration for the CT study. We classified EU + CT findings as benign or malignant causes and we compared our results with the final diagnosis. Results: The combination of EU + CT correctly diag-nosed 38 out of the 39 cases with a sensitivity of 97%. Correct diagnosis was established in all malignant cases (n = 17) but one benign case consistent with blood clots in the upper urinary tract was incorrectly diagnosed as a multicentric urothelial carcinoma. Sensitivity, specificity, and accuracy for the diagnosis of the underlying cause with EU + CT was 100%, 95%, and 97%, respectively. The final diagnoses were: urothelial carcinoma (n = 10), stone disease (n = 10), bladder tumor (n = 4), benign post-treatment ureteral stenosis (n = 4), ureteral inva¬sion (n = 3), benign bladder disease (n = 2), urinary tract infections (n = 2), crossing vessels (n = 1), urete-ropelvic junction obstruction (n = 1), retrocaval ureter (n = 1), and blood clots in the upper urinary tract due to bleeding renal metastasis from lung cancer (n = 1).