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
Describe focal impaired awareness seizure
- A seizure that starts in one area or side of the brain and the person is not aware of their surroundings during it is called focal (onset) impaired awareness seizure.
- This term replaces complex partial seizures. The word “onset” is optional.
- Focal impaired awareness seizures typically last 1 to 2 minutes.
- These seizures may have an aura (or warning, which technically is itself a focal aware seizure).
- These seizures include automatisms (such as lip smacking, picking at clothes, fumbling), becoming unaware of surroundings, and wandering.
Describe focal aware seizure
A focal onset seizure begins in one side of the brain. They were previously called partial seizures. Focal onset seizures are the most common type of seizure experienced by people with epilepsy. For short, the term focal seizure can be used.
When the seizure begins in one side of the brain and the person has no loss of awareness of their surroundings during it, it is called a focal onset aware seizure. This type of seizure was previously called a simple partial seizure.
Describe focal to bilateral tonic-clonic seizure
These seizures are called focal to bilateral tonic-clonic, because they start in a limited area on one side of the brain and spread to involve both sides. This is different from a generalized onset tonic-clonic seizure, which starts on both sides of the brain.
Focal onset seizures have an abnormal region of brain leading to the electrical storm of a seizure. The place and cause of focal onset may not be detectable by testing. Generalized onset seizures are believed to result from neurochemical and genetic abnormalities widespread throughout brain, and no focal injured brain region is involved.
Describe syncope
Syncope is a temporary loss of consciousness usually related to insufficient blood flow to the brain. It’s also called fainting or “passing out.”
It most often occurs when blood pressure is too low (hypotension) and the heart doesn’t pump enough oxygen to the brain. It can be benign or a symptom of an underlying medical condition.
Describe parasomnia
Parasomnias are a group of sleep disorders that involve unwanted events or experiences that occur while you are falling asleep, sleeping or waking up. Parasomnias may include abnormal movements, behaviors, emotions, perceptions or dreams. Although the behaviors may be complex and appear purposeful to others, you remain asleep during the event and often have no memory that it occurred. If you have a parasomnia, you may find it hard to sleep through the night.
