Compressive Fourier-Domain Intensity Coupling (C-FOCUS) enables near-millimeter deep imaging in the intact mouse brain in vivo

TL;DR

C-FOCUS is a novel method combining Fourier-domain modulation and compressive sensing to significantly improve deep-tissue imaging depth in vivo, enabling high-resolution, transcranial imaging in the intact mouse brain beyond 900 micrometers.

Contribution

The paper introduces C-FOCUS, a new active scattering correction technique that enhances two-photon microscopy depth and resolution using Fourier modulation and compressive sensing.

Findings

Achieves imaging depths over 900 micrometers in vivo.

Enables transcranial imaging through the skull.

Increases fluorescence intensity by over 20 times.

Abstract

Two-photon microscopy is a powerful tool for in vivo imaging, but its imaging depth is typically limited to a few hundred microns due to tissue scattering, even with existing scattering correction techniques. Moreover, most active scattering correction methods are restricted to small regions by the optical memory effect. Here, we introduce compressive Fourier-domain intensity coupling for scattering correction (C-FOCUS), an active scattering correction approach that integrates Fourier-domain intensity modulation with compressive sensing for two-photon microscopy. Using C-FOCUS, we demonstrate high-resolution imaging of YFP-labeled neurons and FITC-labeled blood vessels at depths exceeding 900 um in the intact mouse brain in vivo. Furthermore, we achieve transcranial imaging of YFP-labeled dendritic structures through the intact adult mouse skull. C-FOCUS enables high-contrast fluorescence imaging at depths previously inaccessible using two-photon microscopy with 1035 nm excitation, enhancing fluorescence intensity by over 20-fold compared to uncorrected imaging. C-FOCUS provides a broadly applicable strategy for rapid, deep-tissue optical imaging in vivo.