EEG--a valuable tool in early diagnosis of Angelman syndrome

Angelman Syndrome (happy puppet syndrome) is one of the genetic diseases causing developmental delay in children. Late diagnosis used to be the rule because of delayed appearance of disease markers such as craniofacial dysmorphism, ataxia, unprovoked laughter and seizure. However, reports have described characteristic EEG changes such as 2-3 Hz large amplitude slow wave paroxysms which appear early and are quite specific to the syndrome. With EEG aid, we made very early diagnosis in a 9 month-old young infant. And we would like to advocate the use of EEG study in cryptogenic psychomotor retardation in children.