Dual-Energy CT Pulmonary Angiography: Quantification of Disease Burden and Impact on Management
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Purpose of Review
Computed tomography pulmonary angiography (CTPA) has become the imaging modality of choice for patients with suspected pulmonary embolism (PE). Post-processing techniques currently available for dual-energy CT pulmonary angiography (DE-CTPA) enhance image quality and provide additional value in the diagnosis of PE. The objective of this article is to summarize these recent developments and discuss the appropriate use of DE-CTPA post-processing applications.
DE-CTPA post-processing applications enable reconstruction of virtual monoenergetic images (VMI) and color-coded iodine-perfusion maps to increase contrast conditions and visualize lung perfusion defects in case of embolic occlusion of pulmonary arteries. Both techniques revealed a superior diagnostic performance for the detection of pulmonary emboli and assessment of the pulmonary perfusion compared to the standard image reconstructions.
DE-CTPA is a well-established method for excluding or diagnosing PE. Continued developments in DE-CTPA post-processing techniques improve patient management and allow for a quantification of disease burden.
KeywordsDual-energy computed tomography Computed tomography pulmonary angiography Pulmonary embolism Pulmonary perfusion Diagnostic accuracy
Compliance with Ethical Guidelines
Conflict of interest
Simon S. Martin, Marly van Assen, L. Parkwood Griffith, Maximilian J. Bauer, and Thomas J. Vogl each declare no potential conflicts of interest. Carlo N. De Cecco reports a grant from Siemens. Akos Varga-Szemes reports a grant from Siemens and is a consultant for Guerbet. Julian L. Wichmann reports personal fees from Siemens and GE Healthcare. U. Joseph Schoepf reports receives institutional research support from Astellas, Bayer, General Electric, and Siemens Healthineers. Dr. Schoepf has received honoraria for speaking and consulting from Bayer, Guerbet, HeartFlow Inc., and Siemens Healthineers.
Human and Animal Rights Statement
All reported studies/experiments with human or animal subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
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