Generalised electrographic seizures presenting as perioral myoclonia.

A 41-year-old man, during a neurological consultation, reported "chin twitching" over a period of a week, which was diagnosed as intermittent perioral myoclonia. With only one tonic-clonic seizure seven years before, he had mentioned several episodes of chin twitching over the years. In the clinic, there were intermittent chin movements without apparent confusion, as he was able to provide a complete history and was fully oriented with intact memory. His video-EEG showed paroxysms of polyspike and slow-wave activity, with the longest burst-free interval being 20 seconds. Discharges were maximal over the fronto-central regions, correlating with the chin myoclonus. He was able to tap his hand continuously, and remained alert. The case represents an atypical presentation of idiopathic generalised epilepsy without manifestation of absence or limb myoclonus. Although juvenile myoclonic epilepsy and other idiopathic epilepsies are rarely associated with perioral myoclonia, this sign was the principal clinical feature for this patient. Oral treatment with levetiracetam resolved his seizures.