1700 nm optical coherence microscopy enables minimally invasive, volumetric, deep tissue optical biopsy of the mouse brain in vivo

Neuroimaging techniques aim to image deep, with high resolution and minimal invasiveness. Here, we present a label-free optical microscopy approach that achieves a unique balance between these competing goals. Specifically, we design a high numerical aperture optical coherence microscope centered near 1700 nm, where ballistic attenuation in the mouse brain is minimized. Dynamic focusing and image fusion are employed to balance speckle reduction against multiple scattered light reduction. Imaging through the thinned skull to preserve intracranial pressure and minimize inflammation, we present volumetric imaging of cytoarchitecture and myeloarchitecture across the entire mouse neocortex and some sub-cortical regions.