Superficial Bound of the Depth Limit of Two-Photon Imaging in Mouse Brain.

ABSTRACT: Two-photon fluorescence microscopy has been used extensively to probe the structure and functions of cells in living biological tissue. Two-photon excitation generates fluorescence from the focal plane, but also from outside the focal plane, with out-of-focus fluorescence increasing as the focus is pushed deeper into tissue. It has been postulated that the two-photon depth limit, beyond which results become inaccurate, is where in-focus and out-of-focus fluorescence are equal, which we term the balance depth. Calculations suggest that the balance depth should be at ∼600 µm in mouse cortex. Neither the two-photon depth limit nor the balance depth have been measured in brain tissue. We found the depth limit and balance depth of two-photon excitation in mice with GCaMP6 indicator expression i

SUBMITTER: Takasaki K 

PROVIDER: S-EPMC6984806 | biostudies-literature | 2020 Jan/Feb

REPOSITORIES: biostudies-literature