A 3-year magnetic resonance imaging study of cortical lesions in relapse-onset multiple sclerosis.
OBJECTIVE
We assessed the occurrence, extent, and frequency of formation of cortical lesions (CLs) in patients with relapsing-remitting (RR) and secondary progressive (SP) multiple sclerosis (MS), and their relationship with cortical atrophy and disability progression.


METHODS
One-hundred seven MS patients (76 RRMS and 31 SPMS), enrolled in a prospective, longitudinal magnetic resonance imaging (MRI) study, were assessed clinically and by brain MRI (including a double inversion recovery sequence) 3 years after study initiation. CL number and volume, T2 white matter (WM) lesion volume, gray matter fraction, and expanded disability status scale (EDSS) were measured.


RESULTS
At baseline, CLs were detected in 64.4% of RRMS and 74.2% of SPMS patients. During follow-up, 132 new CLs were found in 44 RRMS patients (57.9%; 0.8 new CL/patient/yr) and 61 in 15 SPMS patients (48.4%; 1.0 new CL/patient/yr). Among these patients, only 31 also showed at least 1 new WM lesion. CL number and volume increases were higher in the 52 patients with a clinical worsening compared with those without (p < 0.001). Baseline CL volume correlated with baseline EDSS (r = 0.36, p < 0.001) and EDSS changes over time (r = 0.51, p < 0.001). Baseline CL volume was an independent predictor of EDSS accumulation and GM volume change at follow-up in both patient groups. In SPMS patients, baseline T2 WM lesion volume was another independent predictor of EDSS worsening.


CONCLUSIONS
In relapse-onset MS, CLs accumulate over time and are associated with disability progression. The quantification of CLs might represent an additional useful paraclinical tool to monitor MS evolution.
Calabrese
Massimiliano
M
Multiple Sclerosis Center of Veneto Region, First Neurology Clinic, Department of Neurosciences, University Hospital of Padua, Padua, Italy.
Rocca
Maria A
MA
Atzori
Matteo
M
Mattisi
Irene
I
Favaretto
Alice
A
Perini
Paola
P
Gallo
Paolo
P
Filippi
Massimo
M
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology* / Q000503:physiopathology; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D013997:Time Factors; D055815:Young Adult