Attenuation correction of polychromatic L-shell X-ray fluorescence computed tomography imaging

ABSTRACT

Polychromatic L-shell X-ray fluorescence computed tomography is a promising imaging technique to explore the element distribution of the sample. However, the image quality of large samples would be decreased dramatically due to the present of the self-absorption. In this investigation, an attenuation correction algorithm based on theories related to X-ray fluorescence was proposed. With this method, the attenuation coefficients at the incident energies were expressed as a function of known X-ray energies and unknown platinum concentrations. Then the attenuation coefficients were calculated based on the theories and added in the contribution value of the pixel in Maximum Likelihood Expectation Maximization reconstruction method. The element distributions can be got through continuous iterations. Finally, the feasibility of this method was tested by Monte Carlo simulation. The results indicated that, for a 4-mm diameter phantom containing an object of 2 mm in diameter with 0.10 wt% platinum solutions, the CNR of reconstructed images increased from 53.5 to 203.8 after attenuation correction while the relative error decreases from 97% to 2%.

KEYWORDS:

• Attenuation correction
• polychromatic
• XFCT
• L-shell
• Monte Carlo simulation

Acknowledgements

This work was supported by the National Natural Science Foundation of China [Grant No. 11605106 and 11404192], the Key Research and Development Project of Shandong Province, China [Grant No. 2017GSF220004], the Shandong Province Special Grant for High-Level Overseas Talents [Grant No. tshw20120745] and the research fund of Shandong Academy of Sciences [Grant No. 2017QN001 and KJHZ201805].

Disclosure statement

No potential conflict of interest was reported by the authors.