Dual-Energy Spectral CT: Various Clinical Vascular Applications
| Autor: | Rika Fukui, Haruhiko Machida, Takuya Ishikawa, Yun Shen, Etsuko Tate, Eiko Ueno, Isao Tanaka |
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| Rok vydání: | 2016 |
| Předmět: |
medicine.medical_specialty
Radiography Contrast Media Iterative reconstruction Sensitivity and Specificity 030218 nuclear medicine & medical imaging Radiography Dual-Energy Scanned Projection 03 medical and health sciences 0302 clinical medicine Hounsfield scale Humans Medicine Radiology Nuclear Medicine and imaging medicine.diagnostic_test business.industry Angiography Subtraction Contrast medium 030220 oncology & carcinogenesis Radiographic Image Interpretation Computer-Assisted Radiology Monochromatic color Tomography Tomography X-Ray Computed business Biomedical engineering |
| Zdroj: | RadioGraphics. 36:1215-1232 |
| ISSN: | 1527-1323 0271-5333 |
| DOI: | 10.1148/rg.2016150185 |
| Popis: | Single-source dual-energy (DE) computed tomography (CT) with fast switching of tube voltage allows projection-based image reconstruction, substantial reduction of beam-hardening effects, reconstruction of accurate monochromatic images and material decomposition images (MDIs), and detailing of material composition by using x-ray spectral information. In vascular applications, DE CT is expected to overcome limitations of standard single-energy CT angiography, including patient exposure to nephrotoxic contrast medium and carcinogenic radiation, insufficient contrast vascular enhancement, interference from metallic and beam-hardening artifacts and severe vessel calcification, and limited tissue characterization and perfusion assessment. Acquisition of low-energy monochromatic images and iodine/water MDIs can reasonably reduce contrast agent dose and improve vessel enhancement. Acquisition of virtual noncontrast images, such as water/iodine MDIs, can reduce overall radiation exposure by replacing true noncontrast CT in each examination. Acquisition of monochromatic images by using metal artifact reduction software or acquisition of iodine/water MDIs can reduce metal artifacts with preserved or increased vessel contrast, and subtraction of monochromatic images between two energy levels can subtract coils composed of dense metallic materials. Acquisition of iodine/calcium (ie, hydroxyapatite) MDIs permits subtraction of vessel calcification and improves vessel lumen delineation. Sensitive detection of lipid-rich plaque can be achieved by using fat/water MDIs, the spectral Hounsfield unit curve (energy level vs CT attenuation), and a histogram of effective atomic numbers included in an image. Various MDIs are useful for accurate differentiation among materials with high attenuation values, including contrast medium, calcification, and fresh hematoma. Iodine/water MDIs are used to assess organ perfusion, such as in the lungs and myocardium. Understanding these DE CT techniques enhances the value of CT for vascular applications. (©)RSNA, 2016. |
| Databáze: | OpenAIRE |
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