Dual-Energy CT in Children: Imaging Algorithms and Clinical Applications

Published Online:https://doi.org/10.1148/radiol.2019182289

Dual-energy CT can be safely used in pediatric patients with radiation exposure level that is similar to or less than that of single-energy CT.

Dual-energy CT enables the simultaneous acquisition of CT images at two different x-ray energy spectra. By acquiring high- and low-energy spectral data, dual-energy CT can provide unique qualitative and quantitative information about tissue composition, allowing differentiation of multiple materials including iodinated contrast agents. The two dual-energy CT postprocessing techniques that best exploit the advantages of dual-energy CT in children are the material-decomposition images (which include virtual nonenhanced, iodine, perfused lung blood volume, lung vessel, automated bone removal, and renal stone characterization images) and virtual monoenergetic images. Clinical applications include assessment of the arterial system, lung perfusion, neoplasm, bowel diseases, renal calculi, tumor response to treatment, and metal implants. Of importance, the radiation exposure level of dual-energy CT is equivalent to or less than that of conventional single-energy CT. In this review, the authors discuss the basic principles of the dual-energy CT technologies and postprocessing techniques and review current clinical applications in the pediatric chest and abdomen.

© RSNA, 2019

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Article History

Received: Oct 2 2018
Revision requested: Oct 29 2018
Revision received: Jan 21 2019
Accepted: Jan 24 2019
Published online: Mar 26 2019
Published in print: May 2019