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Updated: Mar 8, 2026
Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images
Published on: November 20, 2015
DT MRI microstructural cortical lesion damage does not explain cognitive impairment in MS
Paolo Preziosa1, Elisabetta Pagani2, Maria E Morelli2
1Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy/Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.
Objective:
We combined double inversion recovery (DIR) and diffusion tensor (DT) magnetic resonance imaging (MRI) to quantify the severity of cortical lesion (CL) microstructural tissue abnormalities in a large cohort of relapse-onset multiple sclerosis (MS) patients and its contribution to cognitive dysfunction.
Methods:
DIR, DT, dual-echo, and three-dimensional (3D) T1-weighted scans were acquired from 149 MS patients and 40 controls. Cognitively impaired (CI) patients had ⩾2 abnormal neuropsychological tests. Diffusivity values in CLs, cortex, white matter (WM) lesions, and normal-appearing (NA) WM were assessed. Predictors of cognitive impairment were identified using a random forest analysis.
Results:
Compared to controls, MS patients had lower normalized brain volume (NBV), gray matter volume (GMV), WM volume, lower fractional anisotropy (FA), and higher mean diffusivity in cortex and normal-appearing white matter (NAWM). A total of 44 (29.5%) patients were CI. Compared to cognitively preserved (CP), CI patients had higher T2 WM lesion volume (LV), lower NBV and GMV, and more severe diffusivity abnormalities in WM lesions, cortex, and NAWM. CL measures did not differ between CI and CP patients. Cortex FA, age, disease duration, T2 WM LV, and GMV best predicted MS-related cognitive impairment (C-statistic = 0.88).
Conclusion:
"Diffuse" GM and NAWM damage and WM lesions, rather than intrinsic CL damage, contribute to cognitive impairment in MS.
Insights
Diffuse gray matter and normal-appearing white matter damage, not cortical lesions, predict cognitive impairment in multiple sclerosis (MS) patients. This finding aids understanding of MS-related cognitive dysfunction.
Area of Science:
- Neuroimaging
- Neurology
- Radiology
Background:
- Multiple sclerosis (MS) is a demyelinating disease affecting the central nervous system.
- Cognitive dysfunction is a common and disabling symptom in MS patients.
- The microstructural basis of cognitive impairment in MS remains incompletely understood.
Purpose of the Study:
- To investigate the contribution of cortical lesion (CL) microstructural abnormalities to cognitive dysfunction in relapse-onset MS.
- To combine double inversion recovery (DIR) and diffusion tensor (DT) magnetic resonance imaging (MRI) for quantitative assessment.
- To identify predictors of cognitive impairment in a large cohort of MS patients.
Main Methods:
- Acquired DIR, DT, dual-echo, and 3D T1-weighted MRI scans from 149 MS patients and 40 controls.
- Assessed diffusivity values in CLs, cortex, white matter (WM) lesions, and normal-appearing (NA) WM.
- Utilized random forest analysis to identify predictors of cognitive impairment (defined as >=2 abnormal neuropsychological tests).
Main Results:
- MS patients exhibited lower normalized brain volume (NBV), gray matter volume (GMV), and WM volume compared to controls.
- Cognitively impaired (CI) MS patients showed higher T2 WM lesion volume (LV), lower NBV and GMV, and more severe diffusivity abnormalities.
- Cortical lesion measures did not differ between cognitively impaired and preserved patients; cortex FA, age, disease duration, T2 WM LV, and GMV predicted cognitive impairment.
Conclusions:
- Diffuse gray matter and normal-appearing white matter damage, alongside white matter lesions, are key contributors to cognitive impairment in MS.
- Intrinsic cortical lesion microstructural damage is not a primary driver of cognitive dysfunction in this MS cohort.
- These findings highlight the widespread nature of MS pathology impacting cognition.
