Epilepsy Flashcards
Define epilepsy.
A neurological disorder that represents a brain state that supports recurrent, unprovoked seizures – it has neurobiological, cognitive, psychological and social consequences.
Define seizures.
Abnormal, paroxysmal changes in the electrical activity of the brain; they reflect large scale synchronous discharges of neuronal networks.
Define epileptogenesis.
The process by which normal brain function progresses towards generation of abnormal electrical activity.
What is the prevalence (%) of epilepsy in the UK?
1%
How many people worldwide have epilepsy?
65 million
How many patients are resistant to treatment?
A third
What is status epilepticus?
A form of epilepsy which is a life-threatening medical emergency. Seizures which last more than 5 minutes (or more than a seizure in 5 min, without regain
of consciousness).
What two broad categories are seizures divided into?
Generalised and focal
What is a generalised seizure?
Arising within and rapidly engaging bilaterally distributed networks
What is a focal seizure?
Originating within networks limited to one hemisphere.
What types of generalised seizures are there? (6)
Absence (typical and atypical) Tonic Clonic Tonic-clonic Atonic Myoclonic (myoclonic, myoclonic-atonic, myoclonic-tonic)
What are focal seizures characterised according to?
Aura, motor, autonomic, awareness/responsiveness (altered or retained).
What might focal seizures evolve to?
Bilateral convulsive seizures
What are the general features/phases of a tonic-clonic seizure? (5)
- Premonition
- Pre-tonic-clonic phase
- Tonic phase
- Clonic phase
- Post-ictal period
What is the pre-tonic-clonic phase?
A few myoclonic jerks or brief clonic seizures
What happens in the tonic phase of a seizure?
Tonic contraction of the axial musculature, limbs and jaw muscles
Respiratory muscle contraction causing the “epileptic cry” and possibly cyanosis
Upward eye deviation and pupillary dilatation
What happens in the clonic phase of a seizure?
Jerks of increasing amplitude followed by relaxation (sphincter opening may occur).
What happens in the postictal phase of a seizure?
Generalized lethargy, decreased muscle tone, headaches, and muscle soreness.
How is epilepsy diagnosed?
Clinical history (occurrence of 2 or more seizures) Investigations - EEG, MRI, fMRI, PET, ECG