Motor cortex activation during treatment may predict therapeutic gains in paretic hand function after stroke.
OBJECTIVE
Functional brain imaging after stroke offers insight into motor network adaptations. This exploratory study examined whether motor cortical activation captured during arm-focused therapy can predict paretic hand functional gains.


METHODS
Eight hemiparetic patients had serial functional MRI (fMRI) while performing a pinch task before, midway, and after 2 weeks of constraint-induced therapy. The Wolf Motor Function Test (WMFT) was performed before and after intervention.


RESULTS
There was a linear reduction in ipsilateral (contralesional) primary motor (M1) activation (voxel counts) across time. The midpoint M1 Laterality Index anticipated post-therapeutic change in time to perform the WMFT. The change in ipsilateral M1 voxel count (pre- to mid-) correlated with the change in mean WMFT time (pre- to post-).


CONCLUSIONS
The relationship between brain activation during treatment and functional gains suggests a use for serial fMRI in predicting the success and optimal duration for a focused therapeutic intervention.
Dong
Yun
Y
Department of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA.
Dobkin
Bruce H
BH
Cen
Steven Y
SY
Wu
Allan D
AD
Winstein
Carolee J
CJ
D000368:Aged; D006225:Hand / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D010291:Paresis / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D026741:Physical Therapy Modalities; D011237:Predictive Value of Tests; D020521:Stroke / Q000150:complications*