Kilohertz frame-rate two-photon tomography

Kazemipour, A.; Novak, O.; Flickinger, D.; Marvin, J. S.; King, J.; Borden, P.; Druckmann, S.; Svoboda, K.; Looger, L. L.; Podgorski, K.

doi:10.1101/357269

bioRxiv · 10.1101/357269

Kilohertz frame-rate two-photon tomography

Kazemipour, A.·Novak, O.·Flickinger, D.·Marvin, J. S.·King, J.·Borden, P.·Druckmann, S.·Svoboda, K.·Looger, L. L.·Podgorski, K.

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Abstract

Point-scanning two-photon microscopy enables high-resolution imaging within scattering specimens such as the mammalian brain, but sequential acquisition of voxels fundamentally limits imaging speed. We developed a two-photon imaging technique that scans lines of excitation across a focal plane at multiple angles and uses prior information to recover high-resolution images at over 1.4 billion voxels per second. Using a structural image as a prior for recording neural activity, we imaged visually-evoked and spontaneous glutamate release across hundreds of dendritic spines in mice at depths over 250 {micro}m and frame-rates over 1 kHz. Dendritic glutamate transients in anaesthetized mice are synchronized within spatially-contiguous domains spanning tens of microns at frequencies ranging from 1-100 Hz. We demonstrate high-speed recording of acetylcholine and calcium sensors, 3D single-particle tracking, and imaging in densely-labeled cortex. Our method surpasses limits on the speed of raster-scanned imaging imposed by fluorescence lifetime.

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Kazemipour, A., Novak, O., Flickinger, D., Marvin, J. S., King, J., Borden, P., Druckmann, S., Svoboda, K., Looger, L. L., Podgorski, K.. 2018-06-28. Kilohertz frame-rate two-photon tomography. https://doi.org/10.1101/357269

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