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arXiv · 1910.10557

Optimizing contrast and spatial resolution in hard X-ray tomography of medically relevant tissues

Griffin Rodgers·Georg Schulz·Hans Deyhle·Willy Kuo·Christoph Rau·Timm Weitkamp·Bert Müller
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Abstract

Hard X-ray tomography with Paganin's widespread single-distance phase retrieval filter improves contrast-to-noise ratio (CNR) while reducing spatial resolution (SR). We demonstrate that a Gaussian filter provided larger CNR at high SR with interpretable density measurements for two medically relevant soft tissue samples. Paganin's filter produced larger CNR at low SR, though \emph{a priori} assumptions were generally false and image quality gains diminish for CNR $>1$. Therefore, simple absorption measurements of low-$Z$ specimens combined with Gaussian filtering can provide improved image quality and model-independent density measurements compared to single-distance phase retrieval.

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Griffin Rodgers, Georg Schulz, Hans Deyhle, Willy Kuo, Christoph Rau, Timm Weitkamp, Bert Müller. 2019-10-23. Optimizing contrast and spatial resolution in hard X-ray tomography of medically relevant tissues. https://doi.org/10.1063/1.5133742

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