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arXiv · 2003.00006

Dynamic contrast in scanning microscopic OCT

Michael Münter·Malte vom Endt·Mario Pieper·Malte Casper·Martin Ahrens·Tabea Kohlfaerber·Ramtin Rahmanzadeh·Peter König·Gereon Hüttmann·Hinnerk Schulz-Hildebrandt
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Abstract

While optical coherence tomography (OCT) provides a resolution down to 1 micrometer it has difficulties to visualize cellular structures due to a lack of scattering contrast. By evaluating signal fluctuations, a significant contrast enhancement was demonstrated using time-domain full-field OCT (FF-OCT), which makes cellular and subcellular structures visible. The putative cause of the dynamic OCT signal is ATP-dependent motion of cellular structures in a sub-micrometer range, which provides histology-like contrast. Here we demonstrate dynamic contrast with a scanning frequency-domain OCT (FD-OCT). Given the inherent sectional imaging geometry, scanning FD-OCT provides depth-resolved images across tissue layers, a perspective known from histopathology, much faster and more efficiently than FF-OCT. Both, shorter acquisition times and tomographic depth-sectioning reduce the sensitivity of dynamic contrast for bulk tissue motion artifacts and simplify their correction in post-processing. The implementation of dynamic contrast makes microscopic FD-OCT a promising tool for histological analysis of unstained tissues.

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Michael Münter, Malte vom Endt, Mario Pieper, Malte Casper, Martin Ahrens, Tabea Kohlfaerber, Ramtin Rahmanzadeh, Peter König, Gereon Hüttmann, Hinnerk Schulz-Hildebrandt. 2020-02-28. Dynamic contrast in scanning microscopic OCT. https://doi.org/10.1364/ol.396134

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