Conference Paper

Penalized-likelihood sinogram restoration for CT artifact correction

Dept. of Radiol., Chicago Univ., IL, USA
DOI: 10.1109/NSSMIC.2004.1466396 Conference: Nuclear Science Symposium Conference Record, 2004 IEEE, Volume: 5
Source: IEEE Xplore


The computerized tomography (CT) sinogram preprocessing was formulated as a statistical restoration problem in which the goal is to obtain the best possible estimate of the line integrals needed for reconstruction from the set of noisy, degraded detector measurments. A general imaging model relating the degraded measurements to the ideal sinogram was presented and propose to estimate the ideal line integrals by iteratively maximizing an appropriate penallized statistical likelihood function. Image reconstruction can then proceed by use of existing, non-iterative approaches. Exponentiated, beam-hardened line integrals with a sharply peaked kernel with low tails approximately 13 channels wide was convolved, to simulate the effects of off-local radiation.

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Available from: Patrick Jean La Riviere, Mar 10, 2015
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