Multi-energy-spectrum CT image reconstruction method based on projection estimation

Abstract

The invention discloses a multi-energy-spectrum CT image reconstruction method based on projection estimation, wherein the method is used for reconstruction of density images of various base materials of a measured object. The method comprises the steps of directly reconstructing energy images of the measured object from collected multicolor projection data according to a traditional single-energy CT reconstruction method, calculating the line integral of each energy image in the radial directions of all other energy spectrums, estimating multicolor projections of a current energy spectrum in the directions, obtaining the multicolor projections with the consistent geometrical parameters, calibrating a various base material division function, dividing the estimated multicolor projections with the consistent geometrical parameters into the line integrals of the various base materials, and reconstructing the corresponding density images of the various base materials through the line integrals of the various base materials. The multi-energy-spectrum CT image reconstruction method based on projection estimation is simple, practical and suitable for multi-energy-spectrum CT image reconstruction when the geometrical parameters of the multicolor projections are not consistent. Compared with the prior art, the multi-energy-spectrum CT image reconstruction method has the advantage that high-quality images can be reconstructed only by estimating the multicolor projections with the consistent geometrical parameters through the measured projection data.

Description

technical field [0001] The present invention relates to the technical field of X-ray CT imaging, in particular to a multi-energy spectral CT image reconstruction method based on projection estimation. Background technique [0002] X-ray computed tomography (X-ray CT for short) is a technology that uses the principle of interaction between X-rays and matter to image the internal information of objects. X-ray CT technology is not only a conventional means of medical diagnosis and treatment, but also an important industrial support technology, which is widely used in the non-destructive testing of key components in various fields. Currently commonly used X-ray tubes cannot emit ideal single-energy X-ray beams, but emit polychromatic X-ray beams that obey a certain spectral distribution. The data collected by scanning is polychromatic projection data, so traditional CT is also called mono-energy spectrum. CT. Single-energy spectrum CT uses only one X-ray energy spectrum to sca...

AI Technical Summary

Problems solved by technology

This method has simple steps and high imaging quality, but it is only applicable to the situation where the polychromatic projection geometric parameters of various energy spectra are consistent, so it is not suitable for the current multi-energy spectral CT system

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