Dual energy imaging in cardiothoracic pathologies: A primer for radiologists and clinicians

• Published in: European journal of radiology Open Vol. 8; p. 100324
• Main Authors: Gupta, Amit, Kikano, Elias G, Bera, Kaustav, Baruah, Dhiraj, Saboo, Sachin S, Lennartz, Simon, Hokamp, Nils Große, Gholamrezanezhad, Ali, Gilkeson, Robert C, Laukamp, Kai R
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-01-2021; Elsevier
• Subjects: Dual energy CT; Dual energy radiography; Photoelectric effect; SVC; Dual energy CT; PACS; TAVI; TNC; VNC; kV; SPECT; Photoelectric effect; BT; NPV; SNR; PPV; Dual energy radiography; eGFR; CAD; AI; NIH; DECT; CR; PCD; VMI; keV; PET; DESR; eGFR, estimated glomerular filtration rate; SVC, superior vena cava; CAD, computer-aided detection; VMI, virtual mono-energetic images; BT, blalock-taussig; NIH, national institute of health; NPV, negative predictive value; PPV, positive predictive value; VNC, virtual non-contrast images; PET, positron emission tomography; PACS, picture archiving and communication system; CR, computed radiography; SPECT, single photon emission computed tomography; TNC, true non contrast; kV, kilo volt; keV, kilo electron volt; AI, artificial intelligence; TAVI, transcatheter aortic valve implantation; DESR, dual-energy subtraction radiography; SNR, signal to noise ratio; PCD, photon-counting detector; DECT, dual-energy computed tomography
• ISSN: 2352-0477; 2352-0477
• DOI: 10.1016/j.ejro.2021.100324

Recent advances in dual-energy imaging techniques, dual-energy subtraction radiography (DESR) and dual-energy CT (DECT), offer new and useful additional information to conventional imaging, thus improving assessment of cardiothoracic abnormalities. DESR facilitates detection and characterization of pulmonary nodules. Other advantages of DESR include better depiction of pleural, lung parenchymal, airway and chest wall abnormalities, detection of foreign bodies and indwelling devices, improved visualization of cardiac and coronary artery calcifications helping in risk stratification of coronary artery disease, and diagnosing conditions like constrictive pericarditis and valvular stenosis. Commercially available DECT approaches are classified into emission based (dual rotation/spin, dual source, rapid kilovoltage switching and split beam) and detector-based (dual layer) systems. DECT provide several specialized image reconstructions. Virtual non-contrast images (VNC) allow for radiation dose reduction by obviating need for true non contrast images, low energy virtual mono-energetic images (VMI) boost contrast enhancement and help in salvaging otherwise non-diagnostic vascular studies, high energy VMI reduce beam hardening artifacts from metallic hardware or dense contrast material, and iodine density images allow quantitative and qualitative assessment of enhancement/iodine distribution. The large amount of data generated by DECT can affect interpreting physician efficiency but also limit clinical adoption of the technology. Optimization of the existing workflow and streamlining the integration between post-processing software and picture archiving and communication system (PACS) is therefore warranted.