In vivo imaging of cortical pathology in multiple sclerosis using ultra-high field MRI.
OBJECTIVE
We used ultra-high field MRI to visualize cortical lesion types described by neuropathology in 16 patients with multiple sclerosis (MS) compared with 8 age-matched controls; to characterize the contrast properties of cortical lesions including T2*, T2, T1, and phase images; and to investigate the relationship between cortical lesion types and clinical data.


METHODS
We collected, on a 7-T scanner, 2-dimensional fast low-angle shot (FLASH)-T2*-weighted spoiled gradient-echo, T2-weighted turbo spin-echo (TSE) images (0.33 x 033 x 1 mm(3)), and a 3-dimensional magnetization-prepared rapid gradient echo.


RESULTS
Overall, 199 cortical lesions were detected in patients on both FLASH-T2* and T2-TSE scans. Seven-tesla MRI allowed for characterization of cortical plaques into type I (leukocortical), type II (intracortical), and type III/IV (subpial extending partly or completely through the cortical width) lesions as described histopathologically. Types III and IV were the most frequent type of cortical plaques (50.2%), followed by type I (36.2%) and type II (13.6%) lesions. Each lesion type was more frequent in secondary progressive than in relapsing-remitting MS. This difference, however, was significant only for type III/IV lesions. T2*-weighted images showed the highest, while phase images showed the lowest, contrast-to-noise ratio for all cortical lesion types. In patients, the number of type III/IV lesions was associated with greater disability (p < 0.02 by Spearman test) and older age (p < 0.04 by Spearman test).


CONCLUSIONS
Seven-tesla MRI detected different histologic cortical lesion types in our small multiple sclerosis (MS) sample, suggesting, if validated in a larger population, that it may prove a valuable tool to assess the contribution of cortical MS pathology to clinical disability.
Mainero
Caterina
C
Athinoula Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA. caterina@nmr.mgh.harvard.edu
Benner
T
T
Radding
A
A
van der Kouwe
A
A
Jensen
R
R
Rosen
B R
BR
Kinkel
R P
RP
D000328:Adult; D017677:Age Distribution; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology* / Q000503:physiopathology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology / Q000503:physiopathology; D009410:Nerve Degeneration / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index