Spectral detector computed tomography (SDCT) is a novel technology that uses two layers of detectors to simultaneously collect low and high energy data. Spectral data is used to generate conventional polyenergetic images as well as dedicated spectral images including virtual monoenergetic and material composition (iodine-only, virtual unenhanced, effective atomic number) images. This paper provides an overview of SDCT technology and a description of some spectral image types.
View Article and Find Full Text PDFRecent technical advances in multi-detector row CT have resulted in lower radiation dose, improved temporal and spatial resolution, decreased scan time, and improved tissue differentiation. Lower radiation doses have resulted from the use of pre-patient z collimators, the availability of thin-slice axial data acquisition, the increased efficiency of ECG-based tube current modulation, and the implementation of iterative reconstruction algorithms. Faster gantry rotation and the simultaneous use of two x-ray sources have led to improvements in temporal resolution, and gains in spatial resolution have been achieved through application of the flying x-ray focal-spot technique in the z-direction.
View Article and Find Full Text PDFJ Cardiovasc Comput Tomogr
March 2009
The acquisition of diagnostic cardiovascular computed tomography (CT) images requires careful preparation of the patient before scanning. Guidelines for patient preparation are largely dictated by scanner capabilities and the technical limits they impose on patient-specific characteristics. The objective of this paper is to highlight procedures for patient screening, premedication, instruction, positioning, and electrocardiographic (ECG) lead placement.
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