Early structural changes in acute MS lesions assessed by serial magnetization transfer studies.
BACKGROUND
Whether acute MS lesions are primarily inflammatory or demyelinative is unresolved. Our study examined acute MS lesions longitudinally by quantitative magnetization transfer (MT), an MRI technique that identifies tissue integrity and destruction.


METHODS
Four MS patients were studied by serial MRI including MT, conventional T2-weighted images, and postgadolinium T1-weighted images for 9 to 12 months. In 15 new lesions, the MT ratio (MTR) was calculated retrospectively.


RESULTS
In 13 lesions, a marked decrease in the MTR was present early during the first 2 months after the onset of the lesion and was followed by a variable increase. In two other lesions, the MTR progressively declined.


CONCLUSIONS
These results suggest that major early structural changes compatible with demyelination and followed by remyelination and gliosis, or by continuous demyelination, occur in new MS lesions. The various MTR profiles provide in vivo confirmation of the current knowledge of the progression in MS lesions. Furthermore, MTR may be used to monitor in vivo drug efficacy in new MS lesions.
Dousset
V
V
Laboratoire de Neurobiologie et Neuro-imagerie Expérimentales, Université Victor-Segalen Bordeaux 2, France.
Gayou
A
A
Brochet
B
B
Caille
J M
JM
D000328:Adult; D003711:Demyelinating Diseases / Q000175:diagnosis*; D018450:Disease Progression; D005260:Female; D005911:Gliosis / Q000175:diagnosis*; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis*