This infographic offers a concise overview of spectral CT, a broader term that includes dual-energy CT technologies. Spectral CT acquires attenuation data at different energy levels rather than a single conventional dataset.
The content is organised in four sections, each of which can also be read on its own.
Technical background
Spectral CT is based on the energy-dependent attenuation of materials.
The main technical implementations include dual-layer detector CT, dual-source CT and fast kV-switching. Typical outputs include monoenergetic images, iodine maps, virtual non-contrast images and z-effective maps.
Clinical applications
The applications highlighted include lesion detection and characterisation in oncologic imaging, evaluation of acute abdominal conditions and active bleeding, improved vessel assessment in CT angiography and myocardial evaluation, and musculoskeletal applications such as gout and bone marrow edema.
Diagnostic value
Spectral CT may reduce radiation dose by avoiding additional scan phases and may enable contrast media reduction in selected protocols (around 30%). It adds iodine density and quantitative information, and it may improve lesion conspicuity and tissue characterisation.
Drawbacks and limitations
Spectral CT requires dedicated training, post-processing and workflow integration. Quantitative parameters are not fully interchangeable, and performance and outputs vary across vendors and scanner platforms.
Some spectral reconstructions may be noisier or less robust than standard images.
This is an initiative of Springer Health+ with an unrestricted educational grant of Bracco, with the scientific support of Prof. Damiano Caruso, Sapienza University of Rome, Italy.