The onset of Lennox-Gastaut syndrome (LGS) does not begin with a specific type of seizure. But for about one-third of children, the first sign of this disorder is a prolonged epileptic episode known as status epilepticus.1 The names and specific signs of the different seizure types are listed below.
Doctors don’t usually diagnose LGS unless the child is having tonic seizures.2Generally, muscles tighten (this can happen to a specific set of muscles, or most muscle groups at once), the eyes roll back, and pupils dilate.2 Tonic seizures can cause faster heartbeats and a temporary stop in breathing.3 They occur most often during sleep and usually last 10 to 60 seconds.3 Tonic seizures can cause a patient who is standing to be thrown to the ground (known as a drop attack).2
A child who has LGS may experience a number of different types of seizures.2
Atonic seizures are also considered drop attacks2 because they cause head nods, loss of posture, and sagging at the knees.3 They are usually very brief, lasting between 1 and 4 seconds.3
This is the second most common seizure assiocated with LGS.2
Atypical absences are characterized by a gradual onset and termination2 as well as staring, pauses in activity, and a lack of response.3 They are generally 5 to 30 seconds long.3
Myoclonic seizures consist of sporadic jerks.4 They usually happen in the same way on both sides of the body.4
In the first phase of tonic-clonic seizures, the stiffening associated with tonic seizures occurs.4 It then gradually changes to the clonic phase, in which the muscles quickly switch between contraction and relaxation.4
Clonic and partial-onset seizures are also associated with LGS.2
Remember that LGS, just like other epilepsies, is more than seizures. Often, children with epilepsy have behavioral problems as well.2 And just as you need to understand the different types of seizures, you’ll need to understand the causes of behavioral problems and ways to approach them. Watch a video of experts talking about navigating these issues.
Learn more: Behavioral issues »
||Epilepsy syndromes. Epilepsy Foundation Web site. http://www.epilepsyfoundation.org/about/types/syndromes/lg.cfm. Accessed July 31, 2012.|
||Arzimanoglou A, French J, Blume WT, et al. Lennox-Gastaut syndrome: a consensus approach on diagnosis, assessment, management, and trial methodology. Lancet Neurol. 2009;8:82-93.|
||Crumrine PK. Lennox-Gastaut syndrome. J Child Neurol. 2002;17(suppl 1):S70-75.|
||Benbadis SR. Epileptic seizures and syndromes. Neurol Clin. 2001;19(2):251-270.|
Hear parents recall their children's first signs of LGS in our Minute by Minute