Table 2: EEG features of Ohtahara syndrome and early myoclonic encephalopathy.

Feature of burst-suppression patternOhtahara syndromeEarly myoclonic encephalopathy

AppearanceUsually seen at the onset of the diseaseSeen later; most distinct at 1–5 months of age
DisappearanceWithin the first 6 monthsPersists for longer periods
State in which it presentsBoth sleeping and waking statesExclusively present or enhanced during sleep
Burst-to-burst intervalsShorterLonger
Evolution to hypsarrhythmiaFrequentMay be a transient feature