# Estimating the spectrum in computed tomography via Kullback–Leibler divergence constrained optimization

@article{Ha2019EstimatingTS, title={Estimating the spectrum in computed tomography via Kullback–Leibler divergence constrained optimization}, author={Wooseok Ha and Emil Y. Sidky and Rina Foygel Barber and Taly Gilat Schmidt and Xiaochuan Pan}, journal={Medical Physics}, year={2019}, volume={46}, pages={81–92} }

PURPOSE
We study the problem of spectrum estimation from transmission data of a known phantom. The goal is to reconstruct an x-ray spectrum that can accurately model the x-ray transmission curves and reflects a realistic shape of the typical energy spectra of the CT system.
METHODS
Spectrum estimation is posed as an optimization problem with x-ray spectrum as unknown variables, and a Kullback-Leibler (KL)-divergence constraint is employed to incorporate prior knowledge of the spectrum and…

## 11 Citations

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The results of this study indicated that the accuracy of SECT calibration is comparable with that of DECT using biological tissues, and is the first to validate the physical density estimation both in SECT and Dect using human-type phantoms.

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