Meng Zhang, Presenter: Nothing to Disclose

Hong Zeng MD, PhD, Abstract Co-Author: Nothing to Disclose

Chang-jiang Sun MS, Abstract Co-Author: Nothing to Disclose

Yan Lv BA, Abstract Co-Author: Nothing to Disclose

Lin Liu MD, PhD, Abstract Co-Author: Nothing to Disclose

To assess the radiation dose and conspicuity of clear-cell renal cell carcinoma with single-phase enhanced split-bolus multidetector spectral CT imaging.

Ninety patients with suspected renal malignancies were randomly divided into two groups to receive single-phase enhanced split-bolus spectral CT (group A) and single-dose traditional double-phase dynamic enhanced CT (group B). Group A: 70ml contrast agent was injected by bolus; 25s later, 50ml contrast agent was injected; thereafter 40ml physiological saline was injected at the same rate. At 70s after the first injection of contrast agent, spectral CT was performed. The optimal monochromatic energy (keV) images were reconstructed.Group B: 120ml contrast agent was injected, the arterial-phase scan was performed when the arterial CT value reached 100Hu, and at a delay of 60s after the first scan, the venous-phase scan was performed. The BMI and radiation dose were recorded. t test, Fisher exact test, and Mann-Whitney test were used for statistical analysis.

In group A, 43 cases were clear-cell renal cell carcinoma, 1 case was chromophobe renal cell carcinoma, and 1 case was renal angiomyolipoma with minimal fat. In group B, 44 cases were clear-cell renal cell carcinomaand 1 case was papillary renal cell carcinoma. There were no statistically significant differences in age, body weight, sex and BMI between two groups (35/45;38/45). The optimal keVwas 58keV for visualizing renal tumors and 67keV for renal arteries.The conspicuity of tumors and CNR in 58kev(1.7±0.02and10.3±3.2)were better than those in group B(1.08±0.04and 5.3±2.2). All inter-group comparisons showed P<0.01. The CT values of renal arteries in 58kev and group B were equivalent (198±20.3HU vs. 203±14.5HU, P>0.05), while the CT value of renal veins in 67kev was higher than that in group B (200±34.0HU vs. 140±12.6HU). The DLP of group A was 735 mGy•cm ± 162, significantly lower than that of group B (1032 mGy • cm ± 324) (P<0.01).

In visualizing clear-cell renal cell carcinoma, renal arteries and veins, single-phase enhanced split-bolus spectral CT is better than traditional double-phase dynamic enhanced CT, with the radiation dose decreased by 28.78%.

Low radiation dose single-phase enhanced split-bolus spectral CT imaging can be widely used in visualizing clear-cell renal cell carcinoma, renal arteries and veins.

Zhang, M, Zeng, H, Sun, C, Lv, Y, Liu, L, Assessment of Radiation Dose and Conspicuity of Clear-cell Renal Cell Carcinoma with Split-Bolus Multidetector Spectral CT Imaging.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018440.html