Daniele Marin MD, Presenter: Nothing to Disclose

Achille Mileto MD, Abstract Co-Author: Nothing to Disclose

Daniela Barbara Husarik MD, Abstract Co-Author: Nothing to Disclose

Mustafa Rifaat Bashir MD, Abstract Co-Author: Research support, Siemens AG Research support, Bayer AG

Rendon C. Nelson MD, Abstract Co-Author: Consultant, General Electric Company Consultant, Nemoto Kyorindo Co, Ltd Consultant, VoxelMetrix, LLC Research support, Bracco Group Research support, Becton, Dickinson and Company Speakers Bureau, Siemens AG Royalties, Wolters Kluwer nv

Daniel Tobias Boll MD, Abstract Co-Author: Research Grant, Siemens AG Research Grant, Koninklijke Philips NV Research Grant, Bracco Group

To assess the impact of patient habitus, acquisition parameters, detector efficiencies, and reconstruction techniques on the accuracy of iodine quantification using dual-source dual-energy CT (DECT).

Two phantoms simulating small and large patients were developed. Phantoms contained 20 iodine solutions mimicking vascular and parenchymal enhancement (ranging from 0 to 400 HU) and 30 iodine solutions simulating enhancement of the urinary collecting system (400 to 2000 HU). DECT acquisition was performed using two second-generation dual-source DECT scanners equipped with standard and integrated electronics detector technologies. DECT was performed with 80/140 kVp and 100/140 kVp dual-energy pairs. DECT raw datasets were reconstructed using filtered backprojection (FBP), and iterative reconstruction at two different levels (SAFIRE I and V). Accuracy of iodine quantification was assessed as absolute percentage error (APE) and evaluated by ANOVA. A univariate GLM analysis was performed to assess the presence of synergistic effects between DECT parameter combinations.

Accuracy for iodine quantification was significantly higher for the small compared to the large phantoms (APE, 9.2%±7.5 vs. 24.3%±26.1, P=0.0001), the integrated compared to the conventional detectors (APE, 14.8%±20.6 vs. 18.8%±20.4; P=0.006), and SAFIRE V compared to SAFIRE I and FBP reconstructions (APE, 15.2%±18.1 vs. 16.1%±17.6 and 18.9%±20.4; P≤0.003). Significant synergism was observed when the most effective detector efficiency and reconstruction technique were combined with habitus-adapted dual energy pairs.

In a second-generation dual-source DECT system, the accuracy of iodine quantification can be dramatically improved by an optimal choice and combination of acquisition parameters, detector efficiency, and reconstruction techniques.

Improvements in iodine quantification using DECT may allow detection of subtle variations in parenchymal blood supply, which may be clinically relevant for oncologic and cardiovascular imaging applications.

Marin, D, Mileto, A, Husarik, D, Bashir, M, Nelson, R, Boll, D, Impact of Acquisition, Detection, and Reconstruction Techniques on the Accuracy of Iodine Quantification Using a Second-generation Dual-source Dual-energy MDCT.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008037.html