Adaptive optics two photon microscopy with direct wavefront sensing using autofluorescent guide-stars

AbstractImaging of the brain in its native state at high resolution poses major challenges to visualization techniques. Two-photon microscopy integrated with the thinned-skull or optical clearing skull technique provides a minimally invasive tool for in vivo imaging of the cortex of mice without activating immune response and inducing brain injury. However, the imaging contrast and resolution are severely compromised by the optical heterogeneity of the skull, limiting the imaging depth to the superficial layer. Here, we develop adaptive optics two-photon microscopy for high-resolution transcranial imaging of layer 5 pyramidal neurons up to 700 μm below pia in living mice. In particular, an optimized configuration of imaging system and new wavefront sensing algorithm are proposed for accurate correction for the aberrations induced by the skull window and brain tissue. We investigated microglia-plaque interaction in living brain of Alzheimer’s disease and demonstrated high-precision laser dendrotomy and single-spine ablation.

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Multidither coherent optical adaptive technique for deep tissue two-photon microscopy

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545819420033 ◽

2019 ◽

Vol 12 (04) ◽

pp. 1942003 ◽

Cited By ~ 1

Author(s):

Biwei Zhang ◽

Wei Gong ◽

Chenxue Wu ◽

Lejia Hu ◽

Xinpei Zhu ◽

...

Keyword(s):

Adaptive Optics ◽

Diffraction Theory ◽

Fluorescence Signal ◽

Two Photon Microscopy ◽

Scalar Diffraction ◽

Two Photon ◽

Scalar Diffraction Theory ◽

Adaptive Technique ◽

Photon Imaging ◽

Two Photon Imaging

Two-photon microscopy normally suffers from the scattering of the tissue in biological imaging. Multidither coherent optical adaptive technique (COAT) can correct the scattered wavefront in parallel. However, the determination of the corrective phases may not be completely accurate using conventional method, which undermines the performance of this technique. In this paper, we theoretically demonstrate a method that can obtain more accurate corrective phases by determining the phase values from the square root of the fluorescence signal. A numerical simulation model is established to study the performance of adaptive optics in two-photon microscopy by combining scalar diffraction theory with vector diffraction theory. The results show that the distortion of the wavefront can be corrected more thoroughly with our method in two-photon imaging. In our simulation, with the scattering from a 450-[Formula: see text]m-thick mouse brain tissue, excitation focal spots with higher peak-to-background ratio (PBR) and images with higher contrast can be obtained. Hence, further enhancement of the multidither COAT correction performance in two-photon imaging can be expected.

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