32 patients with clinically verified epileptic seizures (26 primarily
generalized, six partial) due to cerebrovascular disorders were studie
d and the findings of EEG mapping, routine EEG and CT were compared. A
significant more frequent occurrence of focal abnormalities in EEG ma
pping could be observed: Focal abnormalities were obtained by means of
EEG mapping in 22 patients (69%) and by means of routine EEG in ten p
atients (31%). In twenty patients (63%) the results of EEG mapping and
routine EEG were concordant. Focal lesions in CT were found in 21 pat
ients (66%). Focal changes corresponding with focal lesions in CT were
found by means of EEG mapping in 15 patients (71%) but only in six pa
tients (29%) using routine EEG. Thus a significantly better correlatio
n between focal lesions in CT and focal changes in EEG mapping compare
d to those in routine EEG could be observed. Statistical comparison of
the averaged power spectra of patients with and without CT lesions re
vealed statistically significant differences in the theta-delta-range
between these two patients groups (p < 0,05).