Laura Harsan (Medical Physics, Advanced Molecular Imaging Research Group, Department of Radiology, University Hospital Freiburg)

The Bernstein Center Freiburg

Bernstein Seminar

Laura Harsan

Medical Physics
Advanced Molecular Imaging Research Group
Department of Radiology
University Hospital Freiburg
 

Mapping the living mouse brain neural architecture with diffusion MRI: applications in animal models of brain disorders

Abstract:
A major challenge in neuroscience is to accurately decipher and reconstruct in-vivo the entire brain circuitry at microscopic level. Histological tracing methods applied in animal models represented until recently the gold standard for investigating the structural brain connectivity pattern.
One of the most exciting developments in neuroimaging, which possibly stands as a non-invasive alternative to the histological tracing methods and extends its applicability to longitudinal human and animal studies, is Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) and fiber tractography (FT)^1,2. Probing the tissue microstructure by means of spatial encoding of water molecules movements, DT-MRI and FT provide a non-invasive window into the brain connectivity that was not available previously³. These approaches demonstrate their importance for gaining insight into the organization of neural networks associated with pathological conditions, or for identifying developmental/genetic cues responsible for the formation of altered brain connectivity profiles.
This presentation will summarize our experience in imaging at a microscopic scale the living mouse brain structural connectivity⁵ using DT-MRI and FT, in different animal models of brain pathology. We explore as well the biological basis of the obtained connectivity profiles, by comparative assessment using histological tract tracing and myelin staining. Exquisite brain anatomical details are revealed by combining MRI technologies for data acquisition (high field scanners – 9.4T and 7T – and Cryoprobe technology for the acquisition) and new post-processing algorithms. In mouse models of brain disorders we demonstrate remodeling and altering of brain neural circuits trough active plasticity mechanisms. We further discuss the potential of DT-MRI as a tool for performing a high-throughput screen of mouse models designed to explore the pathophysiological causes of major human brain diseases.

 

 

Host: Dominik von Elverfeldt