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bioRxiv · 10.1101/2020.12.16.423076

Spatial frequency-based image reconstruction to improve image contrast in multi-offset adaptive optics ophthalmoscopy

Mece, P.·Gofas, E.·Rui, Y.·Zhang, M.·Sahel, J.-A.·Rossi, E. A.
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Abstract

Off-axis detection methods in adaptive optics (AO) ophthalmoscopy can enhance image contrast of translucent retinal structures such as cone inner segments and retinal ganglion cells layer neurons. Here, we propose a 2D optical model showing that the phase contrast produced by these methods depends on the offset orientation. While one axis provides an asymmetric light distribution, hence a high phase contrast, the perpendicular axis provides a symmetric one, thus a substantially lower contrast. We support this model with in-vivo human data acquired with a multi-offset AO scanning light ophthalmoscope. Then, using this finding, we provide a post-processing method, named Spatial frequency-based iMAge ReconsTruction (SMART), to optimally combine images from different off-axis detector orientations, significantly increasing the structural cellular contrast of in-vivo human retinal neurons such as conne inner segment, putative rods and retinal ganglion cells.

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Mece, P., Gofas, E., Rui, Y., Zhang, M., Sahel, J.-A., Rossi, E. A.. 2020-12-16. Spatial frequency-based image reconstruction to improve image contrast in multi-offset adaptive optics ophthalmoscopy. https://doi.org/10.1101/2020.12.16.423076

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