[Electroencephalographic study of brain-infarction in dogs (author's transl)]

The evaluation of EEG-findings during the acute phase of stroke-patients is somewhat difficult particularly in regard to the voltage-production, less in regard to the temporary retardation of frequency. Within comparable neurophysiological and biochemical examinations of the experimental brain-infarct under standardized conditions of silicon-rubber-embolus was introduced intracarotideally and an occlusion of the media-trunk evoked. One day prior to the embolisation and on the first, third and fifth day thereafter EEG-derivation took place which were stored on analogous-tape, digitalized and were then confronted with the FFT-Algorithm. From the statistical point of view four animal groups were the result: HO-group (control group), H1-, H3- and H5-group (each time N = 6). Visual evaluation of the curves, descriptive and inferential statistics of the spectral EEG estimators showed a significant loss of power within five days after the infarction; it always was more distinct across the focal side than across the not immediately involved hemisphere. On the fifth day the original level of voltage was almost reached again. From the clinical standpoint the neurological deficits had practically been disappeared. The biochemical finishing of the dog-brains -- the results of which are planned to be confronted with the electrophysiological results in another paper -- in accordance with the papers of other authors brings close the assumption that the decrease of tension i.e. the loss of power of the electric potential during the first days after infarction is combined with a temporary decrease of the energetic potential of the metabolically active corticocerebral cells which is tied to the phosphagene-system of the highly energetical phosphates and metabolites of the energy-metabolism in the brain.