Detection and quantification of regional cortical gray matter damage in multiple sclerosis utilizing gradient echo...

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Cortical gray matter (GM) damage is a key feature of multiple sclerosis (MS).
• Standard MRI techniques often fail to detect cortical GM lesions.
• Cortical volume loss is measurable but may not fully capture GM injury.

Purpose of the Study:

• To demonstrate the reliability and quantitative accuracy of gradient echo MRI for assessing cortical GM damage in MS.
• To establish R2(*) values as potential biomarkers for MS-related brain tissue injury.
• To correlate MRI-derived measures with neurocognitive test performance in MS patients.

Main Methods:

• High-resolution multi-gradient echo MRI was employed to map R2(*) values in cortical and white matter regions.
• Voxel spread function method corrected for background field gradient artifacts.
• Age-adjusted R2(*) values (ΔR2(*)) and cortical thickness were calculated and analyzed in MS patients and healthy controls (HCs).

Main Results:

• MS patients exhibited lower ΔR2(*) values in cortical GM and normal-appearing white matter (NAWM) compared to HCs.
• Cortical GM ΔR2(*) values correlated significantly with Symbol Digit Modalities Test (SDMT) and Paced Auditory Serial Addition Test (PASAT) scores.
• These correlations were stronger than those observed with volumetric measures, indicating greater sensitivity to MS-related changes.

Conclusions:

• Quantitative R2(*) mapping using gradient echo MRI is a robust and reproducible method for assessing cortical GM damage in MS.
• This technique provides sensitive biomarkers of tissue injury, particularly in the cerebral cortex, which is challenging for standard MRI.
• R2(*) values show promise for monitoring disease progression and evaluating treatment efficacy in MS.