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bioRxiv · 10.1101/2022.03.05.483143

Bessel-droplet foci enable high-resolution and high-contrast volumetric imaging of synapses and circulation in the brain in vivo

Chen, W.·Zhang, Q.·Natan, R. G.·Fan, J.·Ji, N.
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Abstract

Bessel beam has long been utilized in physics for its ability to maintain lateral confinement during propagation. When used for two-photon fluorescence microscopy, Bessel foci have enabled high-speed volumetric imaging of the brain. At high numeric aperture (NA), however, the substantial energy in the side rings of Bessel foci reduces image contrast. Therefore, a compromise between resolution and contrast has to be made, limiting Bessel foci in microscopy to low NA. Here, we describe a method of generating axially extended Bessel-droplet foci with much suppressed side rings. Shaping the excitation wavefront with novel phase patterns, we generated Bessel-droplet foci of variable NAs at high power throughput and scanned them interferometrically along the axial direction for continuous volume imaging. More resistant to optical aberrations than Bessel foci, Bessel-droplet foci enabled high-resolution and high-contrast volumetric imaging of synaptic anatomy and function as well as lymphatic circulation in the mouse brain in vivo.

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Chen, W., Zhang, Q., Natan, R. G., Fan, J., Ji, N.. 2022-03-06. Bessel-droplet foci enable high-resolution and high-contrast volumetric imaging of synapses and circulation in the brain in vivo. https://doi.org/10.1101/2022.03.05.483143

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