Magnetization transfer magnetic resonance imaging and clinical changes in patients with relapsing-remitting multiple sclerosis.
BACKGROUND
Magnetization transfer (MT) magnetic resonance imaging (MRI) can provide in vivo quantitative estimates of microscopic tissue damage in normal-appearing white matter (NAWM) and gray matter (GM) from patients with multiple sclerosis (MS).


OBJECTIVE
To determine whether a one-time MT MRI can provide markers of short-term disease evolution in patients with relapsing-remitting MS.


METHODS
Eighteen-month observational study.


METHODS
Neuroimaging Research Unit, Scientific Institute and University Ospedale San Raffaele.


METHODS
Twenty-two patients with untreated relapsing-remitting MS.


METHODS
Relapse rate; disability according to the Expanded Disability Status Scale (EDSS); dual-echo, 2-dimensional gradient echo with and without a saturation MT pulse and T1-weighted MRIs of the brain; and MT ratio (MTR) histograms for NAWM and GM.


RESULTS
During the study period, 13 patients (59%) experienced 25 relapses. The median EDSS score was 1.25 (range, 0-3.5) at study entry and 1.75 (range, 0-3) at study exit. Significant, although moderate, correlations were found between average GM MTR values at baseline and EDSS changes during the study period (r = -0.44; P = .04). A trend was observed for the correlation between NAWM MTR values at baseline and the EDSS changes throughout 18 months (r = -0.42; P = .05). For the relation between EDSS changes and baseline GM MTR, the slope of the regression line was -0.5 (95% confidence interval, -1.0 to 0.0), indicating that a decrease in the baseline GM MTR of 1% predicted an increase in the EDSS score of 0.5 point throughout the 18 months.


CONCLUSIONS
This study indicates that a "snapshot" MT MRI assessment detects subtle brain tissue changes that are associated with short-term disability accumulation in patients with relapsing-remitting MS.
Oreja-Guevara
Celia
C
Neuroimaging Research Unit, Department of Neurology, Scientific Institute and University Ospedale San Raffaele, Via Olgettina 60, 20132 Milan, Italy.
Charil
Arnaud
A
Caputo
Domenico
D
Cavarretta
Rosella
R
Sormani
Maria Pia
MP
Filippi
Massimo
M