Cognitive assessment and quantitative magnetic resonance metrics can help to identify benign multiple sclerosis.
BACKGROUND
The definition of benign multiple sclerosis (B-MS) is still controversial. This mainly takes into account the subject's motor ability, with little or no relevance to other important features such as cognition. Moreover, no paraclinical markers are currently available to reliably identify patients who will remain benign in the long term.


OBJECTIVE
To assess, by using quantitative magnetic resonance (MR) metrics, differences in tissue damage between B-MS patients after dividing them into two groups on the basis of their cognitive performance.


METHODS
Forty-seven B-MS patients (Expanded Disability Status Scale score </=3.0 and disease duration >/=15 years) underwent neuropsychological assessment through the Rao Brief Repeatable Battery and the Stroop Test. At that time, B-MS patients underwent conventional brain MR and magnetization transfer (MT) imaging. White matter lesion load, global and regional brain volumes, and MT ratio (MTr) in lesions and normal-appearing brain were measured. Quantitative MR measures were compared in cognitively impaired (CI-MS) and cognitively preserved (CP-MS) patients and in 24 demographically matched healthy controls. Test performance was correlated with MR changes in specific cortical regions.


RESULTS
Eleven patients were classified as CI-MS, and 36 were classified as CP-MS. Both T2-weighted and T1-weighted lesion loads were higher (p = 0.05 and 0.001) in CI-MS than in CP-MS patients. Furthermore, CI-MS patients were characterized by more pronounced decrease in neocortical volume (p = 0.005) and cortical MTr (p = 0.02) values than CP-MS patients. Finally, test performance correlated significantly with MR changes in relevant cortical regions.


CONCLUSIONS
Cognitive assessment and quantitative magnetic resonance can help to reliably identify benign multiple sclerosis patients.
Amato
M P
MP
Department of Neurology, University of Florence, Viale Morgagni 85, 50134 Florence, Italy. mariapia.amato@unifi.it
Portaccio
E
E
Stromillo
M L
ML
Goretti
B
B
Zipoli
V
V
Siracusa
G
G
Battaglini
M
M
Giorgio
A
A
Bartolozzi
M L
ML
Guidi
L
L
Sorbi
S
S
Federico
A
A
De Stefano
N
N
D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology / 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 / Q000523:psychology*; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D011597:Psychomotor Performance