Relationships of brain white matter microstructure with clinical and MR measures in relapsing-remitting multiple sclerosis.
OBJECTIVE
To assess the relationships of microstructural damage in the cerebral white matter (WM), as measured by diffusion tensor imaging (DTI), with clinical parameters and magnetic resonance imaging (MRI) measures of focal tissue damage in patients with multiple sclerosis (MS).


METHODS
Forty-five relapsing-remitting (RR) MS patients (12 male, 33 female; median age = 29 years, Expanded Disability Status Scale (EDSS) = 1.5, disease duration = 3 years) were studied. T2-lesion masks were created and voxelwise DTI analyses performed with Tract-Based Spatial Statistics (TBSS).


RESULTS
T2-lesion volume (T2-LV) was significantly (P < 0.05, corrected) correlated with fractional anisotropy (FA) in both lesions and normal-appearing WM (NAWM). Relationships (P = 0.08, corrected) between increasing EDSS score and decreasing FA were found in the splenium of the corpus callosum (sCC) and along the pyramidal tract (PY). All FA associations were driven by changes in the perpendicular (to primary tract direction) diffusivity. No significant global and voxelwise FA changes were found over a 2-year follow-up.


CONCLUSIONS
FA changes related to clinical disability in RR-MS patients with minor clinical disability are localized to specific WM tracts such as the sCC and PY and are driven by changes in perpendicular diffusivity both within lesions and NAWM. Longitudinal DTI measurements do not seem able to chart the early disease course in the WM of MS patients.
Giorgio
Antonio
A
Centre for Functional MRI of the Brain, University of Oxford, Oxford, UK.
Palace
Jacqueline
J
Johansen-Berg
Heidi
H
Smith
Stephen M
SM
Ropele
Stefan
S
Fuchs
Siegrid
S
Wallner-Blazek
Mirja
M
Enzinger
Christian
C
Fazekas
Franz
F
D000328:Adult; D015415:Biomarkers / Q000032:analysis*; D001921:Brain / Q000378:metabolism / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000378:metabolism* / Q000473:pathology*; D009413:Nerve Fibers, Myelinated / Q000378:metabolism* / Q000473:pathology*; D013223:Statistics as Topic
D015415:Biomarkers