The absence seizure presents the sudden blanking out into space which is caused by the abnormal activity of the brain. The two types of absence seizures include the simple absence seizures which are the blank staring into space for less than 10 seconds and complex absence seizures that can additionally include various movements such as blinking or hand gestures. The absence seizure particularly occurs in the children between the ages of 4 to 14. These individuals usually continue their activity before the seizure. In some of the case, the absence seizures can occur as much as 100 times a day. Medications can prevent the onset of absence seizures, although most of the children may stop experiencing them by the age of 18.
Childhood absence epilepsy
This is an epilepsy syndrome characterized by the absence seizures that can begin in young children between the age of 3 and 11. Most of the children are not aware of the event they experienced and continue their activity before the seizure. This type may occur during exercise and the children with the frequent absence seizures can also present learning difficulties. Around 1 in 3 children may exhibit additional abnormalities such as memory problem and poor concentration. The cause of this type of epilepsy appears to be genetic where around 1 out of 3 families have reported a family member with seizures. It is estimated that around 1 in 10 children who are brother or sister of childhood absence epilepsy have the chance of developing this as well. This condition is usually diagnosed after the evaluation of the child’s history, other medical condition and in addition presenting learning difficulties. An EEG test will seek to identify the possible seizure activity. In most cases, the children will be required to hyperventilate which is a very quick breathing that can trigger the absence seizure in around 80% of the cases. Most of the children respond well to treatment and the seizure disappears by mid-adolescence.
Juvenile absence epilepsy
This is a relatively common epilepsy syndrome and can occur in another epilepsy syndrome such as juvenile myoclonic epilepsy. The symptoms usually appear around the ages of 9 and 12 but can start as early as 5 years. This presents the absence seizures where they may stare blankly into space and sometimes associated with the eyelid flickering and lip smacking. Children with this type can also have longer absence seizures that can last as long as 45 seconds. Although this seizure can occur several times a day, it is not as frequent as childhood absence epilepsy. Some of the children can also present tonic-clonic seizures and brief myoclonic seizures. The diagnosis is based on the evaluation of the child’s history and EEG test. The response to the treatment is usually good but certain cases have been reported to be resistant to medications and in these cases further evaluation may be necessary such as MRI scan and genetic tests.
References
https://www.epilepsy.org.uk/info/syndromes/juvenile-absence-epilepsy
http://www.epilepsy.com/learn/types-epilepsy-syndromes/childhood-absence-epilepsy
http://www.epilepsy.com/learn/types-seizures/absence-seizures
