A method and system for dual-energy X-ray CT

Abstract

A method and system for dual-energy X-ray CT are disclosed. In the method, two effects which are predominant, such as the Compton effect and the pair effect, are maintained, and influences of other effects such as the photoelectric effect are eliminated, thus increasing the material decomposition precision. The method and the system are advantageous in that errors caused by direct selection of two effect equations for atomic number Z calculation in material decomposition processes in present dual-energy CT (regardless of keV low energy or MeV high energy) methods can be effectively eliminated, thus greatly improving material decomposition and recognition accuracy of dual-energy CT; and the method and the system are of great significance for applications in clinical medicine, safety inspection, industrial nondestructive testing, and other fields.

Description

technical field [0001] Embodiments of the present invention relate to radiation imaging, and in particular to a material decomposition method for dual-energy X-ray CT (Computerized Tomography) and a corresponding system. Background technique [0002] Although X-ray CT imaging technology has been widely used in the fields of clinical medicine, security inspection and industrial non-destructive testing, the current mainstream CT technology uses a single X-ray energy spectrum, uses an energy-integrating detector, and uses CT reconstruction methods to obtain The linear attenuation coefficient distribution image inside the scanned object is a grayscale image of the X-ray absorption strength of the substance, which cannot meet the needs of accurate identification of substances pursued by clinical medicine and security inspection. The emergence of X-ray dual-energy CT technology provides a powerful way to achieve accurate material identification. Dual-energy CT collects projection ...

AI Technical Summary

Problems solved by technology

But in fact, because dual-energy CT only collects projection data of high and low energies, theoretically, it can only use the mathematical model of two effects to decompose materials, while ignoring the influence of other effects, such as only considering the photoelectric effect and Compton scattering, while only Compton scattering and electron pair effects are considered in high-energy imaging. Although these approximations enable dual-energy CT imaging to perform material decomposition, they will inevitably bring certain errors, and in some cases these error becomes difficult to ignore

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