Steven Van Hedent MD, Presenter: Nothing to Disclose

Frederik Vandenbroucke MD, Abstract Co-Author: Nothing to Disclose

Nico Buls DSc, PhD, Abstract Co-Author: Medical Advisory Board, General Electric Company

Koenraad Hans Nieboer MD, Abstract Co-Author: Medical Advisory Board, General Electric Company

Michel De Maeseneer MD, Abstract Co-Author: Nothing to Disclose

Johan De Mey, Abstract Co-Author: Research Grant, General Electric Company

Gert Van Gompel PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the diagnostic accuracy of single source dual energy CT (DECT) performed within 24 hours after RF ablation in the detection of residual tumor.

Thirty-three patients with 38 malignant lesions (20 liver, 10 kidney, 8 lung) underwent DECT within 24 hours after RF ablation. DECT data were reconstructed as monochromatic 70 keV images, grayscale iodine (GI) density and color-coded iodine (CCI) density images. Two readers independently rated the presence of residual tumor. The gold standard for presence of residual tumor consisted of follow-up imaging after 8-10 weeks. Statistical analysis consisted of ROC analysis (multicase, multireader). A Bland-Altman plot was used to compare reader agreement and a t-test was performed to assess the significance of these results.

Ten of 38 (26.3%) lesions showed tumor progression at 8-10 weeks. The mean AUC for both readers and all lesions was 0.87 (CI: 0.72-0.96) for 70keV, 0.80 (CI: 0.63-0.91) for CCI and 0.70 (CI: 0.53-0.84) for GI images. Pairwise comparison for the 3 reconstructions showed no significant differences, but interreader variability was high for all three reconstructions (p<0.0001). For liver and lung lesions AUC values were higher on 70 keV images (0.89 and 0.88 respectively), than on CCI (0.81 and 0.69) and GI images (0.78 and 0.50). Pairwise comparison showed no significant differences (P>0.05).  

1.DECT may be a promising method for detection of residual tumor within 24 h after RF ablation. 2. Our study suggests that no difference in accuracy exists between monochromatic 70 keV images, GI, and CCI.  

Detection of residual tumor after RF ablation is clinically important, and DECT may play a role in this setting.

Van Hedent, S, Vandenbroucke, F, Buls, N, Nieboer, K, De Maeseneer, M, De Mey, J, Van Gompel, G, The Diagnostic Accuracy of Dual Energy CT Performed within 24 Hours in the Detection of Residual Tumor Following RF Ablation.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13028840.html