Quantitative imaging of three-dimensional fiber orientation in the human brain via two illumination angles using polarization-sensitive optical coherence tomography

Liu, C.; Ammon, W.; Jones, R.; Nolan, J. C.; Gong, D.; Maffei, C.; Edlow, B. L.; Augustinack, J. C.; Magnain, C.; Yendiki, A. L.; Villiger, M.; Fischl, B.; Wang, H.

doi:10.1101/2023.10.20.563298

bioRxiv · 10.1101/2023.10.20.563298

Quantitative imaging of three-dimensional fiber orientation in the human brain via two illumination angles using polarization-sensitive optical coherence tomography

Liu, C.·Ammon, W.·Jones, R.·Nolan, J. C.·Gong, D.·Maffei, C.·Edlow, B. L.·Augustinack, J. C.·Magnain, C.·Yendiki, A. L.·Villiger, M.·Fischl, B.·Wang, H.

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Abstract

The accurate measurement of three-dimensional (3D) fiber orientation in the brain is crucial for reconstructing fiber pathways and studying their involvement in neurological diseases. Optical imaging methods such as polarization-sensitive optical coherence tomography (PS-OCT) provide important tools to directly quantify fiber orientation at micrometer resolution. However, brain imaging based on the optic axis by PS-OCT so far has been limited to two-dimensional in-plane orientation, preventing the comprehensive study of connectivity in 3D. In this work, we present a novel method to obtain the 3D fiber orientation in full angular space with only two illumination angles. We measure the optic axis orientation and the apparent birefringence by PS-OCT from a normal and a 15 deg tilted illumination, and then apply a computational method yielding the 3D optic axis orientation and true birefringence. We verify that our method accurately recovers a large range of through-plane orientations from -85 deg to 85 deg with a high angular precision. We further present 3D fiber orientation maps of entire coronal sections of human cerebrum and brainstem with 10 m in-plane resolution, revealing unprecedented details of fiber configurations. We envision that further development of our method will open a promising avenue towards large-scale 3D fiber axis mapping in the human brain and other complex fibrous tissues at microscopic level.

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Liu, C., Ammon, W., Jones, R., Nolan, J. C., Gong, D., Maffei, C., Edlow, B. L., Augustinack, J. C., Magnain, C., Yendiki, A. L., Villiger, M., Fischl, B., Wang, H.. 2023-10-23. Quantitative imaging of three-dimensional fiber orientation in the human brain via two illumination angles using polarization-sensitive optical coherence tomography. https://doi.org/10.1101/2023.10.20.563298

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