Bibliographie

Electroencephalography plays a very important role in the diagnosis and course monitoring of epilepsy. The EEG is also able to give decisive clues in diseases other than epilepsy. It is important to know these specific EEG patterns which may assume a key role in the diagnosis of rare neuropediatric diseases. Familiarity with such specific patterns will allow to select only specific investigations for diagnostic confirmation. We report six guiding EEG patterns and the associated disorders:
1. Re-build up phenomena for Moyamoya syndrome.
2. High amplitude alpha-beta activity for lissencephaly type I.
3. Positive spikes during low frequency photostimulation for late infantile neuronal ceroid lipofuscinosis.
4. Periodic high amplitude discharges for subacute sclerosing panencephalitis (SSPE).
5. Burst suppression pattern in non-asphyctic mature newborns for Ohtahara syndrome, non ketotic hyperglycinemia or molybden cofactor deficiency.
6. High amplitude 3-4 HZ activity with small spikes for Angelman syndrome.

An eight-year-old boy with Angelman-(Happy Puppet-)Syndrome is described. Nearly all typical symptoms of the syndrome, especially severe psychomotoric retardation with spontaneous outbursts of laughing and protrusions of the tongue, athetoid movements, typical electroencephalogram and microcephaly, could be found in our patient. The incidence of the Angelman-syndrome may be underestimated.