Mapping polarization-sensitive optical coherence tomography and ultra-high-field diffusion MRI in the macaque brain

Pisharady, P. K.; Yeatts, M.; Farooq, H.; Johnson, M.; Harel, N.; Moeller, S.; Zimmermann, J.; Yacoub, E.; Ugurbil, K.; Heilbronner, S. R.; Lenglet, C.; Akkin, T.

doi:10.1101/2024.04.19.590326

bioRxiv · 10.1101/2024.04.19.590326

Mapping polarization-sensitive optical coherence tomography and ultra-high-field diffusion MRI in the macaque brain

Pisharady, P. K.·Yeatts, M.·Farooq, H.·Johnson, M.·Harel, N.·Moeller, S.·Zimmermann, J.·Yacoub, E.·Ugurbil, K.·Heilbronner, S. R.·Lenglet, C.·Akkin, T.

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Abstract

This paper provides comparisons between microstructure and two-dimensional fiber orientations measured optically using polarization sensitive optical coherence tomography (PS-OCT) and those estimated from ultra-high-field diffusion MRI (dMRI) at 10.5T in the macaque brain. The PS-OCT imaging is done at an in-plane resolution of [~]10 microns in and around the thalamus. Whole brain dMRI is acquired at an isotropic resolution of 0.75 mm. We provide comparisons between cross-polarization and optical orientation from PS-OCT with the fractional anisotropy and two-dimensional orientations extracted from dMRI using a diffusion tensor model. The orientations from PS-OCT are also extracted computationally using a structure tensor. Additionally, we demonstrate the utility of mesoscale, PS-OCT imaging in improving the MRI resolution by learning the mapping between these contrasts using a super-resolution Generative Adversarial Network.

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Pisharady, P. K., Yeatts, M., Farooq, H., Johnson, M., Harel, N., Moeller, S., Zimmermann, J., Yacoub, E., Ugurbil, K., Heilbronner, S. R., Lenglet, C., Akkin, T.. 2024-04-25. Mapping polarization-sensitive optical coherence tomography and ultra-high-field diffusion MRI in the macaque brain. https://doi.org/10.1101/2024.04.19.590326

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