Types of epilepsy
Different types of epilepsy can be classified according to many different parameters.
Types of epileptic seizures
The initial classification is based on the symptoms the patient suffers during the seizure and the location of the discharge that causes the seizure.
- Generalised seizures: the discharge takes place throughout the cerebral cortex.
- Motor seizures: the seizure's symptoms affect the locomotor system. The patient's head and extremities may jerk (cyclonic seizures) or there may be stiffening (tonic seizures) or repeated jerking (clonic seizures), among other symptoms.
- Absence seizures: these involve a sudden absence of consciousness. The person stares into the distance and is immobile for 5 to 30 seconds. They tend to have slight contractions of the eyelids or subtle movements of the lips and hands.
- Focal seizures: these are when the discharge only affects a specific area of the cerebral cortex. Depending on which area is affected there may be different types:
- Motor seizures: motor focal seizures are very similar to generalised motor seizures.
- Gelastic seizure (laughing): this is a very atypical variety that appears in small children who laugh for no reason.
- Sensory seizures: the patient may see or hear non-existent sounds or have visual and auditory hallucinations.
- Psychic seizures: feeling of unreality as if you were in a strange place or an opposite effect of déjà vu or familiarity.
Types of Epilepsy Syndromes
Classification by syndromes takes into account not only seizures but also electrical activity in the brain (EEG), the individual's age, and whether they have any neurological lesions, etc.
- Childhood idiopathic focal epilepsies: these kinds of epilepsy appear in neurologically healthy children (no apparent cause) and have benign development. Some of the specific syndromes include benign epilepsy in childhood with centro-temporal spikes and benign occipital epilepsy in childhood.
- Generalised idiopathic epilepsies: these include epilepsy without any apparent cause and epilepsy with absence seizures or epilepsy with tonic-clonic motor seizures (see types of seizures). This type of epilepsy can be controlled very well with medication. Some specific types of such epilepsy include: Myoclonic epilepsy in childhood, absence epilepsy in childhood, juvenile myoclonic epilepsy, epilepsy with generalised tonic-clonic seizures.
- Reflex epilepsies: these are epileptic seizures caused by photosensitive stimuli such as television-induced epilepsy.
- Epileptic encephalopathies: this kind of epilepsy is caused by a disease or disorder of the encephalon. Specific syndromes include: West Syndrome, Dravet Syndrome, Lennox-Gastaut Syndrome and acquired epileptic aphasia.