Evolution of brain activation with good and poor motor recovery after stroke.
OBJECTIVE
To characterize the evolution of brain activation in stroke patients with variable motor recovery and quantify changes relative to healthy controls.


METHODS
Serial PET activation studies, using a simple finger-tapping task, and quantitative measures of motor performance were obtained in 9 patients (2-7 weeks poststroke and 6 months later) and compared with serial healthy volunteer data.


RESULTS
Patients with moderate impairment and good recovery (n = 5) activated the primary sensorimotor cortex (SM1) contralateral to the paretic hand moved, bilateral supplementary motor area (SMA), contralateral cingulate gyrus, and ipsilateral lateral premotor cortex. Activation in the bilateral SMA was greater at the initial study but reduced over time compared to healthy controls and poor recoverers. Patients with severe impairment and poor recovery (n =4) showed limited activation of contralateral SM1 and SMA at both studies and no significant change over time. A posterior shift in SM1 activation was evident in good and poor recoverers.


CONCLUSIONS
Activation of typical motor regions and recruitment of additional sites occur subacutely poststroke, with evolution to normal patterns in moderately impaired patients who recover well. In comparison, severely impaired, poor-recovery patients show persistent, reduced activation. Dynamic changes in SMA, differentially observed in good recoverers over 6 months, highlight its importance in recovery.
National Stroke Research Institute, Austin Health, Heidelberg West, Victoria, Australia, LaTrobe University, Bundoora, Victoria, Australia. lcarey@nsri.org.au
Leeanne M
LM
Carey
David F
DF
Abbott
Gary F
GF
Egan
Graham J
GJ
O'Keefe
Graham D
GD
Jackson
Julie
J
Bernhardt
Geoffrey A
GA
Donnan
D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D005385:Fingers / Q000503:physiopathology; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D011877:Radionuclide Imaging; D020127:Recovery of Function / Q000502:physiology*