Electroencephalographical-anatomical correlation of brain tumours in infancy and childhood

EEG correlated with anatomical aspects of 198 brain tumours in children gave the following results in hemispheric neoplasms: a rather precise location in 40% of the cases; lateralized in 42%; 14% showed only generalized anomalies and 4% were normal tracings. The findings depended on location and ICP condition, but not on neurological signs nor on histological nature. Basal-midline location (88 tumors) displayed 82.4% abnormal EEGs; 50% pointed to the more invaded hemisphere, mainly from the upper brain stem, ventricles and basal ganglia regions. Hypophyseal tumours gave 50% abnormalities with proved compression of the third ventricle, hypothalamus and cerebral peduncles. In posterior fossa tumours (60 cases), abnormalities are frequent (86.7%), but the localizing value of EEG is uncertain due to bisynchronous bursts mainly in the occipital region; 15% were lateralized with correlating asymmetrical location and/or growth of tumours. Differences compared to adult tumours are mentioned as specially influenced by maturational processes of the brain.