Non-invasive follow-up studies of stroke patients with STA-MCA anastomosis; computerized topography of EEG and 133-xenon inhalation rCBF measurement

Topographic EEG mapping in cerebrovascular disease

Topographic EEG based on the power spectral data were correlated with cortical CBF and CMRO2 which were provided by positron emission tomography (PET) in patients with cerebral infarction. Delta and theta activities correlated negatively with CBF and CMRO2 whereas alpha activity correlated positively. For delta activity, both absolute (AP) and relative power (RP) showed significant correlation with CBF and CMRO2. For alpha activity, RP showed closer correlation with CBF and CMRO2 than did AP. The z-scores for these power data also showed significant correlation with the PET data although the degree of correlations did not improved even with the z-score. Topographic EEG images including AP, RP and their z-score maps well corresponded with the PET images: z-score maps were considered to be useful tool in topographical extraction of the features of the EEG power data.

Topographic EEG in brain ischemia--correlation with blood flow and metabolism

A review is made of topographic EEG analyses in patients with brain ischemia. Features correlating EEG measures and vascular and metabolic studies are presented and discussed within the content of the stage of ischemia. Quantitative EEG data was found to provide useful information regarding the effects of brain ischemia.