Studio video-poligrafico nella sindrome delle assenze con mioclonie periorali

There have been few case reports of perioral myoclonia with absences (POMA) because of the lack of videopolygraphic recordings clarifying the electroencephalogram (EEG)-electromyogram (EMG) correlations. We describe one of the first video-polygraphic studies of POMA in a patient who underwent repeated and prolonged split-screen video-polygraphic recordings. The ictal EEG showed generalized and irregular discharges of spikes or multiple spikes and slow waves, while two concomitant EMG patterns appeared: (1) a rhythmic enhancement of the orbicularis oris and masseter muscles on both sides with minimal asymmetry corresponding to perioral movements, and (2) a progressive increase in muscular tone in the mylohyoideus muscle corresponding to oro-alimentary automatisms. Myoclonic jerks were inconstantly time-locked to the spike component of the spike-wave complex. The evidence of a complex pattern of activation of the facial muscles suggests that the involvement of subcortical central pattern generators, related to masticatory activity, through the disinhibitory effect of the spike-wave discharge is a possible pathophysiological mechanism underlying POMA.