Epilepsy Flashcards
What is epilepsy?
Epilepsy is the tendency to recurrent spontaneous seizures
- A single seizure is not epilepsy
- How difficult it is to provoke
What is a seizure?
The manifestation of abnormal paroxysmal neuronal discharges in part(s) of the brain
- Abnormal excessive firing of neurones
- Increase in coordination in electrical activity (in same phase)= synchronise firing
- Functional failure
What are the incidences of epilepsy and seizures?
Single seizure (lifetime risk): 9% -Incidence high in children and 50+ -Childhood= genetic, older from other predispositions Prevalence of epilepsy Under 20 years: 1% Lifetime 3%
What are the multiple provoking factors for a single seizure?
- Hypoglycaemia
- Electrolyte imbalance
- Acute head injury
- Drug abuse
- Alcohol withdrawal
What is the medical morbidity of epilepsy?
- Injuries
- Side effects of drugs
- Aspiration (loss of swallowing reflex)
- Cognitive decline (poorly controlled, glutamate release)
What is the psychiatric morbidity of epilepsy?
- Depression
- Psychosis
What is the social morbidity of epilepsy?
- Employment
- Driving
- Embarrassment/ reduced confidence
- Social prejudice
Describe the mortality of epilepsy
-Mortality overall is over twice that of the normal population
-Different for different types of epilepsy
-Mortality may be:
=Seizure related
Status epilepticus/ burns/ drowning/ injury
SUDEP (sudden unexpected death)
=Other
Chest infection/ aspiration
Suicide
What is the seizure classification?
-Focal onset (one part of brain) =Aware/ impaired awareness =Motor onset/ non-motor onset =May progress to focal to bilateral tonic-clonic -Generalised Onset (everywhere in brain) =Motor (tonic-clonic/ other) =Non-motor (absence seizures, freezing) -Unknown Onset =Motor (tonic-clonic/ other)/ Non-motor =Unclassified
How are seizures also classed under idiopathic and symptomatic (aetiologies) categories?
- Focal Idiopathic= Benign Rolandic epilepsy
- Focal Symptomatic= temporal, frontal or occipital lobe epilepsy
- Generalised Idiopathic= Childhood absence, juvenile myoclonic
- Generalised Symptomatic= Lennox-Gestaut Syndrome
What history is taken for a diagnosis?
-Semiology: =Warning “aura” (run up) =Event (ictus) =Post-event (recovery phase) =Eyewitnesses
-Trigger:
=Was this a provoked event?
-Risk factors: =FHx =Birth (brain injury, premature) =Febrile convulsions (preschool) =Significant HI (knocked unconscious) =Encephalitis/Meningitis
What tests can be done?
There is no test for epilepsy
We test for the cause of the seizures and the classification of the syndrome
Brain imaging: MRI or CT Head
EEG (recording of brain wave): classification
What is Paroxysmal LOC?
Blackouts
Syncope (posture, cardiac, emotional stress) vs Primary brain event (e.g. seizure & ΔΔ)
Pallor, Posture, Precipitant
ECG, BP, Echocardiogram etc…
What are the drug treatments for Epilepsy?
70% response rate with 1 AED
80& response rate with 2 AEDs
85% response rate with 3 AEDs
15% “medically refractory”- focal epilepsy, structural lesion (epileptogenic zone)
What are the surgery treatments for epilepsy?
TLE:- 80% seizure free
Non TLE:- 50% seizure free
1% risk of stroke or death
Neuro deficits – depends on location