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bioRxiv · 10.1101/2020.05.29.124727

Adaptive optics two-photon endomicroscopy enables deep brain imaging at synaptic resolution over large volumes

Qin, Z.·Chen, C.·He, S.·Wang, Y.·Tam, K. F.·Ip, N. Y.·Qu, J. Y.
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Abstract

Optical deep brain imaging in vivo at high resolution has remained a great challenge over the decades. Two-photon endomicroscopy provides a minimally invasive approach to image buried brain structures, once it is integrated with a gradient refractive index (GRIN) lens embedded in the brain. However, its imaging resolution and field of view are compromised by the intrinsic aberrations of the GRIN lens. Here, we develop a two-photon endomicroscopy by adding adaptive optics based on the direct wavefront sensing, which enables recovery of diffraction-limited resolution in deep brain imaging. A new precompensation strategy plays a critical role to correct aberrations over large volumes and achieve rapid random-access multiplane imaging. We investigate the neuronal plasticity in the hippocampus, a critical deep brain structure, and reveal the relationship between the somatic and dendritic activity of pyramidal neurons.

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Qin, Z., Chen, C., He, S., Wang, Y., Tam, K. F., Ip, N. Y., Qu, J. Y.. 2020-05-31. Adaptive optics two-photon endomicroscopy enables deep brain imaging at synaptic resolution over large volumes. https://doi.org/10.1101/2020.05.29.124727

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