Outcome prediction in acute monohemispheric stroke via magnetoencephalography.
BACKGROUND
Following an ischemic stroke a highly variable clinical outcome is commonly evident despite similar onset symptoms as well as lesion characteristics. The aim of this study was to identify indexes providing early prediction of functional recovery, in addition to clinical severity and lesion dimension at onset of stroke.


METHODS
In 32 patients, magnetoencephalographic (MEG) parameters collected in the acute phase (<10 days from symptoms onset, T0) from affected (AH) and unaffected (UH) hemispheres at rest and evoked by sensory stimuli were evaluated in association with the clinical outcome in a stabilized phase (T1, median 7.8 months) classified with three levels: worsening, partial and full recovery.


RESULTS
Multiple multinomial logistic regression indicated AH gamma and UH delta band powers able to prognosticate clinical outcome at T1. After inclusion in this analysis, lesion volume had the strongest predictive ability, and UH delta band power remained as a predictive factor with a measurable cut-off, maximizing both sensitivity and specificity of the prediction: a patient with UH delta below cut-off would recover to some extent; a patient with UH delta above cut-off would have a probability of about 70% to worsen.


CONCLUSIONS
MEG UH delta and AH gamma band powers were found to provide useful information about long-term outcome prognosis. Only the increase of delta band activity in the unaffected hemisphere contains information about the outcome in addition to the lesion volume.
Tecchio
Franca
F
Istituto di Scienze e Tecnologie della Cognizione (ISTC), CNR, Rome, Italy. franca.tecchio@istc.cnr.it
Pasqualetti
Patrizio
P
Zappasodi
Filippo
F
Tombini
Mario
M
Lupoi
Domenico
D
Vernieri
Fabrizio
F
Rossini
Paolo Maria
PM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D005073:Evoked Potentials, Somatosensory / Q000502:physiology / Q000528:radiation effects; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D012372:ROC Curve; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology*