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is actively tested for it. On the one hand, the patient may not be aware that he loses
consciousness during a seizure. On the other hand, the presence of an automatic behaviour
that is out of context for the situation does not necessarily imply that the patient has lost
consciousness (because he lost ‘control’). Although it is often the impairment of awareness
that defines the disability resulting from a seizure (e.g. implications for driving), other ictal
manifestations can be equally disabling (even when consciousness is preserved).
Furthermore, the terms simple and complex are somewhat intransparent. Simple also has the
connotation of ‘not serious’. It is for all these reasons that the current ILAE proposal has
abandoned the terms simple and complex partial seizure.

Consequently, the term simple partial seizure has been replaced by ‘focal seizure without
loss of awareness’, and complex partial seizure has been replaced by ‘focal seizure with
alteration of awareness’. The term secondarily generalised tonic-clonic seizure has been
abandoned as well, and is replaced by evolving into a bilateral convulsive seizure with tonic
and/or clonic components.

Epileptic spasms

Epileptic spasms are placed separately (i.e. aside from generalised and focal seizures). This
seizure type occurs in infancy and is characterised by tonic flexion of the head, neck and
trunk, with circumflexion of the upper extremities. It is usually seen in infants with extensive
brain abnormalities (e.g. diffuse tuberous sclerosis). Epileptic spasms were considered a type
of generalised seizure. However, they can be seen in children with gross structural lesions
confined to one hemisphere, and surgical treatment can be curative in this setting (implying
a focal aetiology in at least some cases).

Classification of epilepsies

A classification of epilepsies (as opposed to seizures) combines information about seizure
semiology and EEG findings with information from neuroimaging, aetiology and associated
conditions. From an intellectual perspective, it makes sense to classify these parameters
independently.

The 2010 classification scheme streamlines the terminology for aetiology. In particular, the
terms idiopathic, symptomatic and cryptogenic have been abandoned, since it was felt that
these are not always used precisely, and may have different connotations. For example,
idiopathic epilepsies are thought to have a good prognosis and respond well to
anticonvulsants, whereas symptomatic epilepsies are often thought to have a poor prognosis.
The new scheme proposes unidimensional terms for aetiology (genetic, structural/metabolic,
unknown). This subclassification has been criticised as overly simplistic.

Status epilepticus

Seizures are almost always self-limiting. Rarely one may follow another in close succession
(without complete recovery in between seizures), or the ictal activity may be ongoing. Status
epilepticus has been traditionally defined as ongoing seizure activity for 30 minutes or more.
However, most seizures self-limit within five minutes or less. From a pragmatic point of view,
a seizure that lasts longer than five minutes often warrants pharmacological intervention.
Principally, any seizure type listed in Tables 1 and 2 may occur as status epilepticus.

Convulsive status
This is a state of recurrent tonic-clonic seizures without recovery of consciousness between
attacks. It represents a medical emergency with a high morbidity and mortality. Status may