Rapid volumetric optoacoustic imaging of neural dynamics across the mouse brain

Abstract

Ongoing efforts to scale neuroimaging towards direct visualization of mammalian brain-wide neural activity face major challenges, and a large gap still exists between localized optical microscopy looking at rapid cellular-resolved neuronal activities and whole-brain observations of slow hemodynamics and metabolism provided by macroscopic imaging modalities. Optoacoustic imaging holds inherent advantages for deep tissue observations, but to date has not been applied towards direct activity observation in the mammalian brain. Here we demonstrate in vitro and in vivo functional optoacoustic neuroimaging from mice expressing the genetically encoded calcium indicators GCaMP6, effectively bridging the gap between functional microscopy and whole-brain macroscopic neuroimaging. We yielded instantaneous high-resolution 3D snapshots of whole-brain activity maps with single optoacoustic excitations and enabled non-invasive detection of fast neural responses to sensory stimuli in the presence of strong hemoglobin background absorption. These results demonstrate a new enabling technique towards scalable direct neuroimaging at unprecedented penetration depths and spatio-temporal resolutions.

Determination of cell nucleus-to-cytoplasmic ratio using imaging flow cytometry and a combined ultrasound and photoacoustic technique: a comparison study

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Photoacoustic imaging depth comparison at 532-, 800-, and 1064-nm wavelengths: Monte Carlo simulation and experimental validation

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Recent Progress of Nanomedicine in the Treatment of Central Nervous System Diseases

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