Diagnosis
TBDE images showed a left renal soft tissue lesion, measuring 1.8 × 2.1 × 2.1 cm in size, with contrast enhancement compatible with a renal neoplasm. This was later confirmed by PET. There was no evidence of bowel obstruction or the presence of any obstructing lesions. The patient subsequently underwent partial nephrectomy for this unsuspected lesion. Pathology revealed a clear cell renal carcinoma.
Comments
This is a common scenario, in which a finding is observed that would require further testing to characterize for treatment decision. TBDE CT is ideally suited for these patients, allowing simultaneous acquisition of high and low kV datasets in a single scan. The dataset can then be processed in syngo.CT DE Virtual Unenhanced to create either a virtual non-contrast (VNC) (Fig. 1d) image or an iodine map (Figs. 1a, 1c and 2) for presenting and quantifying the iodine uptake which is more useful in clinical practice. In this case, the unsuspected renal mass enhanced 38 HU (CM) from 45.9 HU (VNC) to 83.7 HU (mixed). This change in HU would be close to what might be observed if a “traditional” non-contrast CT acquisition were to be compared to a contrast enhanced acquisition. This approach could eliminate the need of a non-contrast scan. The value of not having to re-call the patient for another exam and avoidance of additional exposure is obvious.
