Achille Mileto MD, Presenter: Nothing to Disclose

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

Ehsan Samei PhD, Abstract Co-Author: Research Grant, Siemens AG Research Grant, General Electric Company Research Grant, Carestream Health, Inc

Tracy Anne Jaffe MD, Abstract Co-Author: Nothing to Disclose

Joshua Wilson PhD, Abstract Co-Author: Nothing to Disclose

Daniele Marin MD, Abstract Co-Author: Nothing to Disclose

To investigate the effect of body size on selection of the optimal monochromatic energy level for maximizing conspicuity of hypervascular liver tumors during late hepatic arterial phase with dual-energy MDCT.

An anthropomorphic liver phantom having three different body sizes and iodine-containing inserts simulating low- and high-contrast hypervascular liver lesions was imaged with dual-energy MDCT and single-energy MDCT at various polychromatic energy levels (80,100,120 and 140 kVp). Dual energy MDCT was also performed in 48 patients with 114 hypervascular liver tumors; virtual monochromatic images were reconstructed at energy levels ranging from 40 to 140 keV at 10 keV increments. The effect of body size and lesion iodine concentration on image noise and tumor-to-liver contrast-to-noise ratio (CNR) was compared among the different datasets for both phantoms and patients.

The highest tumor-to-liver CNR was noted at 80 kVp for all phantom sizes. On virtual monochromatic images, the minimum noise was noted at 70 keV, for small and medium phantom sizes, and at 80 keV, for the large phantom. CNR was highest at 50 keV, for the small and medium phantoms, and at 60 keV, for the large phantom (P<0.0001). Compared with 80 kVp images, optimized monochromatic energy images yielded significantly higher CNR for low-contrast lesions, in all phantom sizes (P<0.0001). The optimal monochromatic energy level for maximizing tumor-to-liver CNR in patients increased proportionally to body size (P<0.0001). 

Selection of the optimal monochromatic energy level for maximizing the conspicuity of hypervascular liver tumors is significantly affected by patient’s body size.

Optimized monochromatic energy images may improve the conspicuity of hypervascular liver tumors in patients having a variety of sizes, which may be particularly beneficial for detecting subtle lesions in patients with cirrhosis.

Mileto, A, Nelson, R, Samei, E, Jaffe, T, Wilson, J, Marin, D, Dual Energy MDCT in Hypervascular Liver Tumors: Effect of Patient Body Size on Selection of the Optimal Monochromatic Energy Level.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011788.html