Open AccessApplications of dual energy CT in clinical practice: A pictorial essay
Author(s) -
Parang Sanghavi,
Bhavin Jankharia
Publication year - 2019
Publication title -
indian journal of radiology and imaging - new series/indian journal of radiology and imaging/indian journal of radiology and imaging
Language(s) - English
Resource type - Journals
eISSN - 0971-3026
pISSN - 0970-2016
DOI - 10.4103/ijri.ijri_241_19
Subject(s) - medicine , attenuation , digital enhanced cordless telecommunications , radiology , nuclear medicine , biomedical engineering , optics , computer science , telecommunications , physics , wireless
In dual-energy CT (DECT), two different x-ray spectra are used to acquire two image datasets of the same region, to allow the analysis of energy-dependent changes in the attenuation of different materials. Each type of material demonstrates a relatively specific change in attenuation between images obtained with a high-energy spectrum and those obtained with a low-energy spectrum. Based on the relatively specific change in attenuation with two different energies, material composition information can be obtained to allow tissue characterization. The DECT ability of material differentiation allows bone removal in various CT angiography studies and bone marrow edema depiction, while with material optimization, metal artefacts can be significantly reduced to almost nil. DECT allows material separation to differentiate uric acid crystals from calcium to determine the composition of urinary calculi and to diagnose gout. Using the DECT ability of material decomposition, iodine maps can be generated, which are useful in the evaluation of any enhancing lesion in the body without the need to obtain a plain scan and allow perfusion maps to be created in cases of pulmonary thromboembolism.