Article

Evolution of motor function during the first months after stroke is
stereotypically bifurcated, consisting of either recovery to about 70% of maximum
possible improvement ("proportional recovery, PROP") or in little to no
improvement ("poor recovery, POOR"). There is currently no evidence that any
rehabilitation treatment will prevent POOR and favor PROP. OBJECTIVE: To perform
a longitudinal and multimodal assessment of functional and structural changes in
brain organization associated with PROP. METHODS: Fugl-Meyer Assessments of the
upper extremity and high-density electroencephalography (EEG) were obtained from
63 patients, diffusion tensor imaging from 46 patients, at 2 and 4 weeks (T0) and
at 3 months (T1) after stroke onset. RESULTS: We confirmed the presence of 2
distinct recovery patterns (PROP and POOR) in our sample. At T0, PROP patients
had greater integrity of the corticospinal tract (CST) and greater EEG functional
connectivity (FC) between the affected hemisphere and rest of the brain, in
particular between the ventral premotor and the primary motor cortex. POOR
patients suffered from degradation of corticocortical and corticofugal fiber
tracts in the affected hemisphere between T0 and T1, which was not observed in
PROP patients. Better initial CST integrity correlated with greater initial
global FC, which was in turn associated with less white matter degradation
between T0 and T1. CONCLUSIONS: These findings suggest links between initial CST
integrity, systems-level cortical network plasticity, reduction of white matter
atrophy, and clinical motor recovery after stroke. This identifies candidate
treatment targets.

Langue : ANGLAIS