[A comparison of EEG mapping with and without visual artefact control in focal cerebral lesions]

In 163 patients with focal cerebral lesions, 43 of them with completed stroke, 43 patients with TIA, 33 patients with ICH and 29 patients with malignant and 15 patients with benign tumors EEG mapping and CT was performed. The results of EEG mapping obtained using automated artifact detection were compared to those achieved by means of visual control of raw EEG. Furthermore the impact of long (850 +/- 250s) or short (32s) analysis time was studied. Eliminating artifacts by means of visual control of raw EEG significantly more positive results were obtained than using automated artifact detection. That was found in patients with as well as in patients without lesions in CT. In relation to etiology a significant difference was found only in cerebrovascular diseases but not in the other patients-groups. Corresponding results were found in 75% of the patients. The visual control provided additional lateralization especially in patients with CS (37%) and TIA (26%). A longer duration of analysed EEG epochs did not increase the number of focal changes in EEG mapping.