Mesoscopic oblique plane microscopy with a diffractive light-sheet for large-scale 4D cellular resolution imaging

Fundamental understanding of large-scale dynamic connectivity within a living organism requires volumetric imaging over a large field of view (FOV) at biologically relevant speed and resolution. However, most microscopy methods make trade-offs between FOV and axial resolution, making it challenging to observe highly dynamic processes at cellular resolution in 3D across mesoscopic scales (e.g., whole zebrafish larva). To overcome this limitation, we have developed mesoscopic oblique plane microscopy (Meso-OPM) with a diffractive light sheet. By augmenting the illumination angle of the light sheet with a transmission grating, we improved the axial resolution approximately sixfold over existing methods and approximately twofold beyond the diffraction limitation of the primary objective lens. We demonstrated a FOV up to 5.4mm x 3.3mm with resolution of 2.5 mu m x 3 mu m x 6 mu m, allowing volumetric imaging of 3D cellular structures with a single scan. ApplyingMeso-OPM for in vivo imaging of zebrafish larvae, we report here in toto wholebody volumetric recordings of neuronal activity at 2 Hz volume rate and whole-body volumetric recordings of blood flowdynamics at 5 Hz with3Dcellular resolution.

Automated summary

To understand large-scale dynamic connectivity in living organisms, researchers have developed a new microscopy method called mesoscopic oblique plane microscopy (Meso-OPM). By using a diffractive light sheet, this method improves axial resolution and allows for imaging with a large field of view and high resolution.