Probing white-matter microstructure with higher-order diffusion tensors and susceptibility tensor MRI

Area of Science:

• Neuroimaging
• Biophysics
• Medical Physics

Background:

• Diffusion MRI is crucial for studying white matter microstructure and brain connectivity.
• Quantitative susceptibility mapping and susceptibility tensor imaging (STI) offer unique insights into white matter structure.
• Integrating diffusion and susceptibility measures may reveal new aspects of white matter physiology.

Purpose of the Study:

• To investigate the relationship between diffusion and magnetic susceptibility in white matter.
• To compare and correlate diffusion and susceptibility metrics in different white matter regions.
• To establish relationships and identify similarities/differences between these imaging modalities.

Main Methods:

• Experiments conducted on phantoms and human brains in vivo.
• Diffusion properties quantified using diffusion tensor and higher-order tensor models.
• Frequency shift and susceptibility tensor measured using quantitative susceptibility mapping and STI.

Main Results:

• Diffusion and susceptibility quantities were compared and correlated in regions with single and multiple fiber orientations.
• Established relationships between diffusion and susceptibility metrics.
• Identified both similarities and differences in the information provided by the two methods.

Conclusions:

• Diffusion MRI and susceptibility MRI provide complementary information on white matter microstructure.
• The integration of these methods allows for a more complete assessment of healthy and diseased brains.
• This combined approach enhances our understanding of white matter's complex physiology.