Both, functional transcranial Doppler ultrasonography (fTCD) and functional
magnetic resonance imaging (fMRI)have been employed to assess hemispheric
language dominance on 9 healthy subjects. Quantitative language laterality
indices of the fTCD and fMRI data have been calculated, representing the de
gree and side of hemispheric laterality assessed by each technique. The fTC
D results relate Po regional cerebral blood flow changes measured by fMRI i
n a highly linear fashion (linear regression analysis, r = 0.97, p < 0.001)
. Based on this close agreement both techniques can be used in a complement
ary way.