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bioRxiv · 10.1101/853200

NIR-II fluorescence microscopic imaging of cortical vasculature in non-human primates

Cai, Z.·Zhu, L.·Wang, M.·Roe, A. W.·Xi, W.·Qian, J.
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Abstract

Vasculature architecture in the brain can provide revealing information about mental and neurological function and disease. Fluorescence imaging in the second near-infrared (NIR-II) regime with less light scattering is a more promising method for detecting cortical vessels than traditional visible and NIR-I modes. Here, for the first time, we developed, NIR-II fluorescence microscopy capabilities for imaging brain vasculature in macaque monkey. The first is a wide-field microscope with high temporal resolution (25 frames/second) for measuring blood flow velocity and cardiac impulse period, and the second is a high spatial resolution (<10 m) confocal microscope producing three-dimensional maps of the cortical microvascular network ([~]500 m deep). Both were designed with flexibility to image various cortical locations on the head. Use of a clinically approved dye provided high brightness in NIR-II region. This comprises an important advance towards studies of neurovascular coupling, stroke, and other diseases relevant to neurovascular health in humans.

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Cai, Z., Zhu, L., Wang, M., Roe, A. W., Xi, W., Qian, J.. 2019-11-25. NIR-II fluorescence microscopic imaging of cortical vasculature in non-human primates. https://doi.org/10.1101/853200

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