Absence seizures with single myoclonic jerks

These two half-sisters have idiopathic generalized epilepsy, which mainly manifests with intractable absence seizures that persist beyond childhood. Single myoclonic jerks occur in the progress of the absence. Absences and occasional GTCS continued in the last follow-up (late teens for the younger sister and age 22 for the oldest one). (First sequence) The younger sister had two seizures captured with video-EEG during sleep at age two years. Note the marked myoclonic jerks during or immediately on termination of generalized spike-wave discharges. Also note that the EEG does not show the polyspike discharges of myoclonic jerks. (Second sequence) The older sister has two absence seizures characterized by eyelid fluttering and a consistent jerk of the head backwards. Breath-counting is not disturbed. (Used with permission from: Panayiotopoulos CP. Perioral myoclonia with absences. In: Panayiotopoulos CP, editor. The Epilepsies: Seizures, Syndromes and Management. Oxford: Bladon Medical Publishing, 2005:324-7.)