Multiple Sclerosis,
October 2001,
vol. 7, no. 5, pp. 290-297(8)
Griffin C.M. [1]; Chard D.T. [1];
Ciccarelli O. [1]; Kapoor R. [1]; Barker G.J. [1]; Thompson A.J. [1]; Miller
D.H. [1] *
[1] NMR Research Unit, Institute
of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square,
London WC1N 3BG, UK
[*] Correspondence: DH Miller
Abstract:
Diffusion tensor magnetic resonance
imaging (DTI) indices are abnormal in patients with established multiple
sclerosis (MS).
The objective of this study was to
examine the diffusion characteristics of MS lesions, normal appearing white
matter (NAWM) and normal appearing grey matter (NAGM) in MS patients with
early relapsing – remitting disease.
A further objective was to investigate
the relationship between three DTI parameters (fractional anisotropy (FA),
mean diffusivity (MD) and volume ratio (VR)) and clinical outcome measures
(Kurtzke expanded disability status scale (EDSS) and MS Functional Composite
Measure) in early disease.
DTI was performed in 28 patients
and 27 controls.
Analysis was carried out using a
region of interest (ROI) approach.
ROIs were placed in 12 NAWM and nine
NAGM regions.
Significant differences were found
in FA, MD and VR between lesions and NAWM (P<0.001 for all three DTI
parameters).
No significant differences were found
between patients and controls when examining NAWM or NAGM, although there
was a trend for abnormal NAWM FA and VR in some regions.
No correlation was found between
DTI parameters in lesions, NAWM or NAGM and the clinical outcome measures.
The lack of significant DTI abnormality
in the NAWM and NAGM may reflect a lack of pathological change or a limited
sensitivity of DTI using ROI methodology.
Previous studies have shown abnormalities
in T1 relaxation time, magnetisation transfer ratio (MTR) and N-Acetyl
aspartate (NAA) in this cohort of patients, and as such, DTI using a region
of interest (ROI) approach may not be as sensitive as other MR techniques
in detecting subtle changes in normal appearing brain tissue in early disease.
© 2001 ingenta