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The
Infantile
Spasms
Resource |
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Generalised idiopathic epilepsies |
Generalised epilepsies are those which have no defined focal area within the
brain; as a result they have generalised symptoms as the whole brain becomes
affected. Idiopathic is a medical term meaning that there is no clear
environmental cause for the epilepsy and it is presumed that genetic factors
predominate. There are usually no other handicaps and the EEG is often normal
between fits. The response to drug treatment is usually good.
Benign myoclonic epilepsy in infants
- rare
- onset in infancy; up to age 3 years
- normal clinical examination and development
- myoclonic spasms involve the upper extremities and head
- attacks occur in day and during light sleep; disappear in deep sleep
- EEG is always abnormal; shows 3 Hz spike and wave complexes during spasms
- neuroimaging is normal
- may be the earliest manifestation of juvenile myoclonic epilepsy
- benign outcome presently expected
Juvenile myoclonic epilepsy
most common primary / idiopathic generalized epilepsy
onset from 8 to 30 years (mean 14 years)
myoclonic, absence and generalized tonic clonic fits
fits occur on awakening
sleep deprivation, alcohol or menstrual periods may be precipitants
Ictal EEG shows polyspikes followed by slow, irregular spike and wave
complexes
photosensitivity is common
good response to valproic acid and clonazepam
Childhood absence epilepsy
uncommon (2 - 5%)
frequent absence fits with abrupt onset and termination
generalized tonic clonic fits are infrequent (<10%)
onset 3 to 12 years; peak 6 to 7 years, female preponderance
neurologically normal subject
3Hz spike and wave complexes is the typical EEG abnormality
some develop generalised tonic clonic fits in adolescence or early
adulthood
Juvenile absence epilepsy
absences tend to occur in clusters
age of onset 8 to 18 years, peak 13 years
more likely to present with generalised tonic clonic fits
more likely to have myoclonic fits
uncertain whether this is a distinct entity from childhood absence
epilepsy
Epilepsy with generalised tonic clonic fits in childhood
about 1.5% of childhood epilepsy
rare generalised tonic clonic fits, typical total fit count is 5
good chance of remission
usually normal intellect (95% or greater)
onset occurs in association with febrile fits
return to Types of
epilepsy
(checked: 15 November 2002)
(update 1.1: 8 November 2002)
(issue 1: 24 March 1998)