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bioRxiv · 10.1101/2021.10.02.462855

Solid optical clearing agents based through-Intact-Skull (TIS) window technique for long-term observation of cortical structure and function in mice

Li, D.·Hu, Z.·Zhang, H.·Zhu, L.·Liu, Y.·Yu, T.·Zhu, J.·Xi, W.·Qian, J.·Zhu, D.
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Abstract

In vivo cortical optical imaging needs to overcome the scattering of skull. Compared to the traditional transcranial surgery-based open-skull glass window and thinned-skull preparation, chemical tissue optical clearing techniques can provide a skull-remained optical access to the brain while maintaining its original environment. However, previously demonstrated skull optical clearing windows could only maintain transparency for a couple of hours and hardly capable for high-resolution monitoring of awake animals. Here, we developed a convenient and easy-handling chronic skull optical clearing technique, named "Through-Intact-Skull (TIS) window", which was compatible with long-term observation at high resolution, and yielded large imaging depth of 900 m for cortical neurovascular visualization. In addition, our TIS window could monitor neuron activity in awake mice for a long term. Therefore, our bio-compatible and non-invasive TIS window is a new promising approach for intravital brain microscopy with great potential for basic research in neuroscience.

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Li, D., Hu, Z., Zhang, H., Zhu, L., Liu, Y., Yu, T., Zhu, J., Xi, W., Qian, J., Zhu, D.. 2021-10-03. Solid optical clearing agents based through-Intact-Skull (TIS) window technique for long-term observation of cortical structure and function in mice. https://doi.org/10.1101/2021.10.02.462855

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