Voxel-wise mapping of cervical cord damage in multiple sclerosis patients with different clinical phenotypes.
OBJECTIVE
To apply voxel-based methods to map the regional distribution of atrophy and T2 hyperintense lesions in the cervical cord of multiple sclerosis (MS) patients with different clinical phenotypes.


METHODS
Brain and cervical cord 3D T1-weighted and T2-weighted scans were acquired from 31 healthy controls (HC) and 77 MS patients (15 clinically isolated syndromes (CIS), 15 relapsing-remitting (RR), 19 benign (B), 15 primary progressive (PP) and 13 secondary progressive (SP) MS). Hyperintense cord lesions were outlined on T2-weighted scans. The T2- and 3D T1-weighted cord images were then analysed using an active surface method which created output images reformatted in planes perpendicular to the estimated cord centre line. These unfolded cervical cord images were co-registered into a common space; then smoothed binary cord masks and lesion masks underwent spatial statistic analysis (SPM8).


RESULTS
No cord atrophy was found in CIS patients versus HC, while PPMS had significant cord atrophy. Clusters of cord atrophy were found in BMS versus RRMS, and in SPMS versus RRMS, BMS and PPMS patients, mainly involving the posterior and lateral cord segments. Cord lesion probability maps showed a significantly greater likelihood of abnormalities in RRMS, PPMS and SPMS than in CIS and BMS patients. The spatial distributions of cord atrophy and cord lesions were not correlated. In progressive MS, regional cord atrophy was correlated with clinical disability and impairment in the pyramidal system.


CONCLUSIONS
Voxel-based assessment of cervical cord damage is feasible and may contribute to a better characterisation of the clinical heterogeneity of MS patients.
Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina, 60-20132 Milan, Italy.
Maria A
MA
Rocca
Paola
P
Valsasina
Dusan
D
Damjanovic
Mark A
MA
Horsfield
Sarlota
S
Mesaros
Tatjana
T
Stosic-Opincal
Jelena
J
Drulovic
Massimo
M
Filippi
D000328:Adult; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology; D016022:Case-Control Studies; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000473:pathology*; D059906:Neuroimaging / Q000379:methods; D013116:Spinal Cord / Q000473:pathology*