Exploratory study of peripheral immune changes associated with diffusion MRI multi-compartment model in temporal lobe...

Area of Science:

• Neuroscience
• Radiology
• Immunology

Background:

• Focal inflammation is a key factor in temporal lobe epilepsy (TLE) seizure initiation and maintenance.
• Previous in vivo studies primarily focused on Positron Emission Tomography (PET) findings.
• The relationship between advanced MRI techniques and peripheral inflammatory markers in TLE remains underexplored.

Purpose of the Study:

• To investigate the association between multicompartment Neurite Orientation Dispersion and Density Imaging (NODDI) measures and peripheral immune cells/inflammatory biomarkers in TLE.
• To explore if NODDI abnormalities in the affected temporal lobe (aTL) correlate with systemic inflammation.
• To assess the potential of NODDI as a non-invasive tool for visualizing neuroinflammation in TLE.

Main Methods:

• Eighteen TLE patients and 18 healthy controls underwent 3 Tesla MRI with high angular resolution diffusion imaging.
• NODDI parameter maps (FISO, FICVF, ODI) were generated and compared between groups.
• Peripheral blood samples from TLE patients were analyzed for immune cells and inflammatory biomarkers, and correlated with NODDI values.

Main Results:

• Increased ODI in the aTL correlated with pro-inflammatory cytokines (e.g., IL-1α, IL-2).
• Decreased neurite density (FICVF) in the aTL correlated with IL-27 and specific T-cell responses (CD3+, CD8+, Th17).
• Increased extracellular/free water (FISO) in the aTL correlated with CXCL10 and T-cell markers (CD3+, CD8+, Th1).

Conclusions:

• Significant relationships exist between NODDI biomarkers of injury/neuroinflammation and peripheral immune markers in the affected temporal lobe of TLE patients.
• These findings support NODDI's potential as a non-invasive method for visualizing neuroinflammation in vivo.
• Further validation could lead to NODDI aiding disease monitoring and personalized treatment strategies in epilepsy.