CT beam hardening correction method based on projection space

doi:10.3969/j.issn.1000-1565.2018.06.014

Abstract

Abstract: X ray spectrum of medical CT imaging system is polychromatic, which will cause CT image hardening artifacts, reduce image quality and interfere diagnosis.Therefore,the correction of the hardening artifacts of CT images is necessary. In this paper, a polynomial fitting correction method is proposed based on projection space optimization for single medium water and water bone mixture. Firstly, the projection correction model and the ideal projection model are constructed. Then, the projection correction model is compared with the ideal projection model to determine the correction coefficient when the difference is minimum. Finally, the correction coefficient is substituted into the projection correction model,and the corrected image can be reconstructed. The simulation results show that the proposed polynomial fitting correction method can remove CT hardening artifacts and improve the image accuracy, which is of great significance in the accurate quantitative analysis of CT.

Key words: computed tomography(CT), beam hardening correction, projection space

CLC Number:

TP391.41

ZHANG Xiaoke, YANG Kun, CHEN Jintao, XUE Linyan, LI Xiaowei. CT beam hardening correction method based on projection space[J]. Journal of Hebei University (Natural Science Edition), 2018, 38(6): 648-655.

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