Sparse angle CT image iterative reconstruction method

Abstract

The invention discloses a sparse angle CT image iterative reconstruction method. The sparse angle CT image iterative reconstruction method includes the steps that original projection data with a spare angle in CT image imaging equipment are collected; a reconstruction image is initialized, and a CT image reconstruction model is constructed; the obtained original projection data with the sparse angle are substituted into the reconstruction model one by one in a two-phase mode by the utilization of the reconstruction model, the image reconstructed in the (K-1)th iteration and the image reconstructed in the (K-2) iteration are linearly combined as an initial value to enter the Kth iteration, and the reconstruction result of the Kth iteration is obtained, wherein K>=3; whether the Kth iteration reconstruction result meets preset conditions or not is judged, and if not, the image reconstructed in the Kth iteration and the image reconstructed in the (K-1)th iteration are linearly combined as an initial value to enter the (K+1)th iteration; if yes, the image data obtained in the Kth iteration is taken as the final reconstruction result, and the image is output. With the sparse angle CT image iterative reconstruction method, image quality is effectively improved, and the convergence of an algorithm is effectively accelerated.

Description

technical field [0001] The invention relates to medical image processing technology, and particularly designs a method for iteratively reconstructing CT images with sparse angles. Background technique [0002] Computed Tomography (CT) technology has been widely used in clinical diagnosis and tumor radiation therapy because of its ability to obtain high-resolution tomographic information. However, the higher X-ray radiation dose has greatly increased the risk of cancer in patients incidence and lifetime cancer mortality. In recent years, with the development of radiation physics and the improvement of the public's self-health awareness, people hope to reduce the radiation dose as much as possible while ensuring the imaging quality. The traditional radiation dose reduction method is mainly achieved by reducing the tube current of the X-ray tube. However, with the reduction of tube current, it is still necessary to obtain hundreds to nearly a thousand projection data, and the...

AI Technical Summary

Problems solved by technology

Although the quality of sparse angle reconstruction has been improved, the reconstruction results often lead to too smooth edges of the image, and the reconstructed image is still not ideal.

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