Conventional and spectral EEG analysis in children treated with cytotoxic agents

One hundred and six EEG investigations were carried out in 17 children with various types of neoplastic disease without cerebral involvement during one or more courses of treatment with cytotoxic agents EEGs were recorded before and 24 hr after administration of the drugs. The EEGs were evaluated visually and by spectral analysis. A transient slowing of the dominant frequency in the alpha band by about 1 Hz and a decrease in the relative power of alpha activity by 20-30% was observed in only 4 patients. These children did not show any clinical or biochemical signs of neurotoxicity. The children did not receive the same antineoplastic treatment. One patient received very high dose methotrexate, 2 patients received vincristine combined with other cytotoxic agents and the other patient received L-asparaginase. It is suggested that EEG changes in patients receiving intravenous cytotoxic treatment usually occur only where there is pre-existing impairment of the blood--cerebrospinal fluid barrier or blood-brain barrier. No clinical signs of epilepsy, new epileptiform waves in the EEG or long-term changes in the background activity of the EEG were observed in this pilot study.