Intravital 3D visualization and segmentation of murine neural networks at micron resolution

Abstract

Optical coherence tomography (OCT) allows label-free, micron-scale 3D imaging of biological tissues’ fine structures with significant depth and large field-of-view. Here we introduce a novel OCT-based neuroimaging setting, accompanied by a feature segmentation algorithm, which enables rapid, accurate, and high-resolution in vivo imaging of 700 μm depth across the mouse cortex. Using a commercial OCT device, we demonstrate 3D reconstruction of microarchitectural elements through a cortical column. Our system is sensitive to structural and cellular changes at micron-scale resolution in vivo, such as those from injury or disease. Therefore, it can serve as a tool to visualize and quantify spatiotemporal brain elasticity patterns. This highly transformative and versatile platform allows accurate investigation of brain cellular architectural changes by quantifying features such as brain cell bodies’ density, volume, and average distance to the nearest cell. Hence, it may assist in longitudinal studies of microstructural tissue alteration in aging, injury, or disease in a living rodent brain.

Diving head-first into brain intravital microscopy

“…Neurons have diverse functional properties; therefore, their classification is important to understand their involvement in disease progression. Similar to microglia, neurons are defined by morphological, physiological and molecular criteria ( 158 , 159 ). Studying these cells during neuropathology is a challenge due to the complex brain microenvironment which create issues in isolating intact neurons for profiling.…”