Brain tissue volume changes in relapsing-remitting multiple sclerosis: correlation with lesion load.
The aim of this study was to simultaneously measure in vivo volumes of gray matter (GM), normal white matter (WM), abnormal white matter (aWM), and cerebro-spinal fluid (CSF), and to assess their relationship in 50 patients with relapsing-remitting multiple sclerosis (RR-MS) (age range, 21-59; mean EDSS, 2.5; mean disease duration, 9.9 years), using an unsupervised multiparametric segmentation procedure applied to brain MR studies. Tissue volumes were normalized to total intracranial volume providing corresponding fractional volumes (fGM, faWM, fWM, and fCSF), subsequently corrected for aWM-related segmentation inaccuracies and adjusted to mean patients' age according to age-related changes measured in 54 normal volunteers (NV) (age range 16-70). In MS patients aWM was 23.8 +/- 29.8 ml (range 0.4-138.8). A significant decrease in fGM was present in MS patients as compared to NV (49.5 +/- 3.2% vs 53.3 +/- 2.1%; P < 0.0001), with a corresponding increase in fCSF (13.0 +/- 3.8% vs 9.1 +/- 2.4%; P < 0.0001). No difference could be detected between the two groups for fWM (37.5 +/- 2.6% vs 37.6 +/- 2.2%). faWM correlated inversely with fGM (R = -0.434, P < 0.001 at regression analysis), and directly with fCSF (R = 0.473, P < 0.001), but not with fWM. There was a significant correlation between disease duration and EDSS, while no relationship was found between EDSS or disease duration and fractional volumes. Brain atrophy in RR-MS is mainly related to GM loss, which correlates with faWM. Both measures do not appear to significantly affect EDSS, which correlates to disease duration.
Quarantelli
Mario
M
Biostructure and Bioimaging Institute, National Council for Research, Building 10, Via Pansini 5, 80131 Naples, Italy. quarante@unina.it
Ciarmiello
Andrea
A
Morra
Vincenzo Brescia
VB
Orefice
Giuseppe
G
Larobina
Michele
M
Lanzillo
Roberta
R
Schiavone
Vittorio
V
Salvatore
Elena
E
Alfano
Bruno
B
Brunetti
Arturo
A
D000328:Adult; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D002555:Cerebrospinal Fluid / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000175:diagnosis*; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D012016:Reference Values; D015203:Reproducibility of Results