Traveling with Lennox – atonic vs. astatic seizures and the Sea of Galilee

Taking the gloves off. Historically, epilepsy is called the falling sickness because of episodes when patients suddenly crash to the ground and lose their posture. These seizures are called atonic or astatic seizures and are often the most troubling events for patients. During these events, patients may seriously hurt themselves. From the epileptological point of view, there is a long debate regarding the nature of these events. Are they purely due to loss of posture or are they associated with a brief myoclonic seizure? Lennox quotes Pierce Clark who states bluntly that describing an astatic seizure without a preceding jerk is due to “faulty clinical observation”. This is when Lennox takes the gloves off.

A drop attack. On Tuesday evening, Zaid and I had Shawarma in a small village overlooking Kinneret, the Sea of Galilee. We had just seen a small epilepsy family that had eventually “condensed” into an epileptic encephalopathy trio. The big screen in the background showed a wrestling match. In my tired mind, the discussion that Lennox had with his opponents regarding the nature of astatic seizures morphed into a full-blown exchange between two wrestlers. Lennox landing a spinning headlock elbow drop on Clark, Gastaut firmly pinned down in a Damascus head-leglock. I think I must have been very tired. Either way, Lennox gets his point across that real astatic seizures do exist.

Israel from space (photo at the Ben Gurion airport, Tel Aviv)

Atonic, astatic, MAE. The nitty-gritty details of seizure classifications can get complicated quickly. In brief, atonic and astatic are often used as synonyms. Lennox suggests that the term astatic should be reserved for seizures that affect the posture of the patient, while the term atonic seizure may be used to describe a seizure where the tonus suddenly drops without affecting posture. This might be the case for brief head drops, for example. The term astatic is used less frequently today but has survived in the term “Myoclonic Astatic Epilepsy” (MAE), an epileptic encephalopathy of childhood that is part of the EuroEPINOMICS-RES project. MAE or Doose Syndrome is one of the phenotypes that has a separate RES working group and that is on the shortlist for trio exome sequencing.

A tribute to Dr. West. In my previous post on myoclonic seizures, I was wondering why Lennox did not mention the 1841 Lancet paper by West. Eventually, I found this reference in the chapter on astatic and atonic seizures. Lennox refers to the head drops of West Syndrome as epilepsia nutans or “head nodding” and regards them as atonic seizures. It is very interesting to see how the Infantile Spasms of West Syndrome are divided up by Lennox as brief events that are atonic and the larger events that he regards as myoclonic.

The odd one out in the petit mal triad. From a 2012 perspective, atonic or astatic seizures seem to be out of place when mentioned in the same breath with absences and myoclonic seizures. Lennox is well aware of this and points out several times that the astatic seizures are associated with a less favourable outcome and that the EEG more often shows slow-spike wave rather than the fast spike-wave variants. The slow-spike wave pattern is now regarded as the hallmark of a syndrome that carries the name of both wrestlers: Lennox-Gastaut syndrome.

On my way home. I am looking back at a busy recruitment and phenotyping week in Israel. In total, we have added 9 new families to our growing collection of  >40 epilepsy families from Israel and Palestine recruited in 2012 for the EuroEPINOMICS family projects. Phenotypically, this week was unexpectedly heavy on the GEFS+ side with a flavour of IGE. I am still waiting to hear from the DFG regarding a major grant that we have submitted for a Trilateral Project regarding the Israel family studies, so keep your fingers crossed.

9 thoughts on “Traveling with Lennox – atonic vs. astatic seizures and the Sea of Galilee

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