Aicardi syndrome: a longitudinal clinical and electroencephalographic study.

We report clinical and EEG follow-up of 6 children with Aicardi syndrome. Age at seizure onset was < 3 months in 5 patients and 4 months in 1 patient. All patients had spasms, and these continued at time of follow-up in 5 patients. Five patients had seizures other than spasms which disappeared during early infancy. Bilateral independent bursts (BIBs) characteristic of Aicardi syndrome were noted in 4 patients. In 1, BIBs showed suppression-burst patterns. BIBs converted to hypsarrhythmia or multifocal spikes with a tendency to BIBs during sleep. BIBs disappeared completely during both waking and sleeping states between the ages of 3 years 1 month and 4 years 9 months. After BIB disappearance, the EEG of 1 patient showed diffuse slow spike-and-wave complexes most of which appeared asynchronously. At onset, 1 patient had early-infantile epileptic encephalopathy with suppression-burst which evolved initially into West syndrome (WS) and then Lennox-Gastaut syndrome (LGS). The other 3 children also had WS.