Epilepsy Flashcards
What is epilepsy?
A paroxysmal disorder in which cerebral cortical neuronal discharges result in intermittent, stereotyped attacks of altered consciousness, motor or sensory function, behaviour or emotion.
-recurrent tendency to siezures
what is the pathogenesis of epilepsy?
abnormal cortical neuronal communication
due to:
- increased connectivity (too many connections)
- increase in excitatory transmission (too many excitatory signals – glutamate)
- failure of inhibitory mechanism (GABA)
What are the causes of epilepsy
Primary (idiopathic): over 50%
Secondary: e.g. vascular/infection/neoplasia/drugs… etc
How are epileptic siezures classified?
- focal (partial)
- generalised (tonic clonic)
What is a partial seizure?
- simple
- complex
This is a seizure which begins focally, in a particular area giving specific s/s
Simple partial seizures:
Where consciousness is retained throughout the attack
Complex partial seizures:
Consciousness is impaired at any stage
They may become secondarily generalised where the patient loses consciousness with clinical evidence of spread across cerebral cortex e.g. bilateral convulsive movements
-Starts focally then loss of consciousness and have tonic-clonic seizures.
Generalised seizure - what is a:
- tonic-clonic
- tonic
- myoclonic
- absence
- atonic
Both cerebral hemispheres are involved from the start of the seizure
Tonic-clonic - grand mal
Tonic – increase stiffness and rigidity
Myoclonic – sporadic jerks
Absence – petit mal (blank stare and no post-ictal confusion)
Atonic – drop attacks: complete loss of tone
Primary generalised epilepsy:
- when does this onset?
- what kind of seizures?
Onset childhood
Tonic-clonic seizure
Describe the nature of the tonic clonic seizures in primary generalised epilepsy:
- what happens before the attack
- what happens during the attack
- what happens after the attack
tonic-clonic seizures (grand-mal)
before an attack vague symptoms of dizziness/irritability convulsion may begin with an epileptic cry – loss of consciousness and collapse tonic phase – generalised muscle spasms occur clonic phase – sharp repetitive muscle jerks tongue biting, incontinence of urine and salivation may occur when jerking stops patient is left unconscious for approx.. 30mins confusion and drowsiness then occur for several hours on recovery usually headache and stiffness or injury from the fall muscular spasms can cause vertebral fractures
What is the treatment for primary generalised tonic-clonic seizures?
Sodium valproate
second line: Lamotrigine/carbamazepine
Absence seizures:
- when does this occur
- is it commoner in males or females
- always begin in childhood (4-8years)
- commoner in girls
Absence seizures:
- describe the attacks
- what is seen on EEG?
attacks occur without warning
child stares blankly into space and stops talking eyes may flutter or roll up under lids recovery occurs within seconds and there may be many daily attacks absences are associated with characteristic EEG abnormalities (3-HZz generalised, symmetrical, spiked wave complexes)
What is the risk of seizures after absence seizures
Risk of seizures as an adult following this is 10%
What is treatment of absence seizures
sodium valproate or ethosuximide
sodium valproate particularly effective if co-existent tonic-clonic seizures in primary generalised epilepsy
Carbamazepine might make these worse
Describe the nature of temporal lobe epilepsy?
This is a complex partial seizure
aura of attack: fear or sensation déjà vu, hallucinations or rising sensation in epigastrium
patients may become confused/anxious and exhibit organised stereotyped movements – automatism
chewing lip smacking can be more complex and sometimes aggressive/violent
Jacksonian epilepsy:
- where do these begin?
- what are these assoc. with?
- what happens after the attack?
- what is epilepsia partialis continua?
focal motor attacks that typically begin in corner of mouth, thumb, index finger or the great toe
movements spread across face or ascend up limb (jacksonian march) generally associated with underlying organic brain disease tumour in motor cortex after attack the affected limb(s) may remain temporarily weak epilepsia partialis continua is a rare form where the attack persists for days, weeks or even months
