EEG recognition of holoprosencephaly and Aicardi syndrome.

Two cases of alobar holoprosencephaly and two of Aicardi syndrome are reported for their highly specific electroencephalographic (EEG) changes. The asynchronous sharp waves and spikes over the frontal regions with decreasing gradient of potential to the occipital leads were seen in alobar holoprosencephaly while burst suppression pattern with total asynchrony between the two hemispheres was seen in Aicardi syndrome. Even though EEG changes cannot be pathognomic of any abnormality, it is suggested that as in conditions like subacute sclerosing panencephalitis and petitmal epilepsy, so also in alobar holoprosencephaly and Aicardi syndrome, the characteristic features seen on EEG may provide the initial clue to the correct diagnosis.