Typical absence seizures during hyperventilation in childhood absence epilepsy

Typical absence seizures in a 4.8-year-old boy with normal development and a history of absence seizures occurring at a frequency of over 10 per day for the last 3 months. During hyperventilation, he suddenly stopped, his eyes opened and stared, and he displayed mild eyelid and atonic body movements and hand rubbing. The duration of the episodes varied between 10 and 20 seconds. During the event, he was unresponsive. (Contributed by Dr. Athanasios Covanis.)