Epilepsy Flashcards
What is epilepsy?
A neurological condition characterised by seizures.
Epilepsy involves recurrent seizures due to abnormal electrical activity in the brain.
What are seizures?
Transient episodes of abnormal electrical activity in the brain.
They can vary in duration and intensity.
What causes seizures?
Imbalance between excitatory (glutamatergic) and inhibitory (GABAergic) neuronal signalling.
This leads to a reduced threshold for neurotransmission.
Which brain lobes are involved in seizures and what are their associated symptoms?
- Frontal lobe: abnormal movements (e.g. thrusting, leg cycling), vocalisation
- Temporal lobe: abnormal sensations (e.g. deja vu)
- Occipital lobe: visual disturbance
Different lobes of the brain can produce different types of seizures.
What are structural abnormalities that can be risk factors for seizures?
- Head injury
- Stroke
- Brain tumours
- Neurodegenerative disease
- Genetic syndromes (e.g. tuberous sclerosis, Dravet syndrome)
These structural issues can disrupt normal brain function.
What neurochemical imbalances can lead to seizures?
- Metabolic/electrolyte imbalance (e.g. hyponatraemia, hypoglycaemia)
- CNS infection (e.g. encephalitis, meningitis)
- Alcohol withdrawal
Imbalances in chemicals that regulate brain activity can provoke seizures.
What are the most common types of seizures in adults?
- Generalised tonic-clonic seizures
- Partial/focal seizures
- Myoclonic seizures
- Tonic seizures
- Atonic seizures
Different types of seizures exhibit distinct characteristics and effects.
What are the most common types of seizures in children?
- Febrile convulsions
- Infantile spasms (Wests syndrome)
- Absence seizures
What characterises generalised seizures?
Affect both cerebral hemispheres and often include a prolonged post-ictal period.
Post-ictal symptoms may include tiredness, confusion, and irritability.
What are the types of generalised seizures?
- Tonic-clonic: muscle stiffening and jerking
- Myoclonic: jerking movements
- Atonic: sudden loss of muscle tone
- Absence: generalised non-motor seizures
Each type presents with different motor symptoms.
What are partial seizures?
Seizures that occur in an isolated brain area, often affecting hearing, speech, memory, and emotions.
Patients may remain awake, with varying levels of awareness.
What are some symptoms of partial seizures?
Deja vu, altered sensations (i.e. strange smells), unusual emotions, abnormal behaviours
What is West syndrome?
Also known as infantile spasms, it presents with clusters of full-body spasms starting around 6 months old.
Hypsarrhythmia on EEG.
It is associated with poor prognosis and developmental regression.
How to manage infantile spasms?
ACTH and Vigabatrin (an antiepileptic)
What characterises febrile convulsions?
Tonic-clonic seizures occurring in children during a high fever, typically between 6 months to 5 years.
They are not caused by epilepsy and usually do not result in lasting damage.
What are key investigations for seizures?
- Capillary blood glucose
- U&Es (to check for hyponatraemia)
- MRI brain (to exclude structural causes)
- EEG
- Video-telemetry
- Patient videos of seizures
These investigations help in diagnosing the cause of seizures.
What is the diagnosis criteria for epilepsy?
Two or more unprovoked seizures more than 24 hours apart, or previously diagnosed with epilepsy syndrome.
A single seizure is not sufficient for diagnosis.
What is the goal of epilepsy management?
To reduce the frequency of seizures.
Management strategies include safety precautions and medical treatment.
Medical management of generalised tonic-clonic seizures in:
a) men and women of non-childbearing age
b) women of childbearing age
Men: sodium valproate
Women of childbearing age: lamotrigine or levetiracetam
What is the medical management for partial seizures in both men and women (including women of childbearing age)?
Lamotrigine or levetiracetam
Medical management of myoclonic seizures in:
a) men & women non-childbearing age
b) women of childbearing age
a) sodium valproate
b) levetiracetam
Medical management of tonic and atonic seizures in:
a) men & women non-childbearing age
b) women of childbearing age
a) sodium valproate
b) lamotrigine
What is the medical management of absence seizures in men and women, including women of childbearing age?
Ethosuximide
What are the side effects of sodium valproate?
- Teratogenic effects (neural tube defects)
- Liver damage and hepatitis
- Hair loss
- Tremor
These side effects are significant considerations in treatment.
What defines status epilepticus?
A seizure lasting >5 minutes, or multiple seizures without regaining consciousness in between.
This condition is a medical emergency.
What is the first step in managing status epilepticus?
Secure airway and provide high-flow O2.
ABCDE approach is crucial in emergency management.
What are the initial medical treatments for status epilepticus?
- Benzodiazepine (buccal midazolam, rectal diazepam, or IV lorazepam)
- If seizure continues: IV levetiracetam, IV phenytoin, or IV sodium valproate
- If unsuccessful: phenobarbital or general anaesthesia
Quick intervention is essential to prevent complications.
