Feasibility of diffusion-tensor and correlated diffusion imaging for studying white-matter microstructural...

Area of Science:

• Neuroimaging
• Neurology
• Infectious Diseases

Background:

• Growing attention on COVID-19's impact on white-matter microstructure, particularly in self-isolated patients.
• Scientific interest in single-shell diffusion magnetic resonance imaging (MRI) methods for detecting neurological effects.

Purpose of the Study:

• To compare the sensitivity of three single-shell diffusion MRI modeling methods for detecting COVID-19-related brain effects.
• To evaluate the performance of diffusion-tensor imaging, diffusion-tensor decomposition of orthogonal moments, and correlated diffusion imaging.

Main Methods:

• Imaging of self-isolated COVID-19 patients and age/sex-matched controls at baseline and 3-month follow-up.
• Application and comparison of diffusion-tensor imaging, diffusion-tensor decomposition, and correlated diffusion imaging.
• Utilized simulations and experimental data to assess method performance.

Main Results:

• Correlated diffusion imaging demonstrated superior sensitivity, uniquely identifying COVID-19-related brain effects among the tested single-shell methods.
• Observed less restricted diffusion in the frontal lobe and more restricted diffusion in the cerebellar white matter of COVID-19 patients.
• Results suggest white-matter pathology in COVID-19 often manifests as changes in tissue diffusivity, with varying b-value sensitivities.

Conclusions:

• Correlated diffusion imaging is a viable single-shell approach for analyzing diffusion changes in COVID-19 patients.
• Identified opposing diffusion patterns in the frontal and cerebellar regions, indicating differential responses to viral infection.
• No significant differences were found at 3-month follow-up, potentially due to cohort size.