Epilepsy Flashcards
What is an epileptic seizure?
Imbalance of exicitatory and inhibitory neurotransmission in the brain, leading to synchronous depolarisation of neurones
Epilepsy has many different causes and seizures can be epileptic or non-epileptic (syncope - fainting). What is idiopathic epilepsy?
Epilepsy of unknown cause
Epilepsy is localised to which 2 parts of the brain?
Telencephalon
Diencephalon
Epilepsy can be focal or generalised. Describe these terms
Focal - one area of brain.
Generalised - whole of both hemispheres result of progression of focal seizures
Focal seizures cause motor abnormalities such as facial twtiching. What do generalise seizures cause?
Loss of consciousness
Tonic-clonic type seizure - ‘typical epileptic fit’
Epilepsy can be caused by anything that causes an imbalance of excitatory and inhibitory neutransmitters in the brain. Give an example of how this can happen? What are these neurotransmitters?
Genetic ionic channel abnormalities or damage to neuronal tissue
GABA - inibitory
Glutamate - excitatory
What is kindling in epilepsy?
Epileptic activity in brain increases number of pacemaker cells recruited
Causes more seizures
What are the 3 terms used to describe frequency of epileptic seizures?
Isolated - 1 in 24 hrs
Cluster - 2 or more in 24 hrs
Status epilepticus - repeated seizures without returning to normal (last over 5 mins)
What can status epileptics cause?
Blood pressure and body temperature rise to dangerous levels
Acidosis causes irreversible changes in the brain
Sevre hypoglycaemia
Organ failure and death
What are the 4 phases to a seizure?
Prodromal phase
Aura
Ictus
Post-ictal phase
What happens in the first phase of a seizure? What is this phase?
Prodromal
Behavioural changes before seizure occurs e.g. whining, hiding
What is the second phase of a seizure and what happens?
Aura
Just before seizure occurs - odd behaviour and autonomic signs e.g. salivating, barking
What is the third phase a seizure? What happens in the?
Ictus
Involuntary muscle movements and twitches
Changes in muscle tone
What is the last phase of a seizure?
Post-ictal phase
Animal is disorientated, behaviour changes and neurological deficits
Is epilepsy a disease? What are the treatment aims of epilepsy?
No - isn’t a disease itself
Due to underlying cause - need to treat the cause and reduce seizures, not treat the epilepsy itself
