Neuro - Epilepsy Flashcards
What is the definition of epilepsy?
Recurrent seizures due to abnormal neuronal excitability
What are the causes of epilepsy?
Traumatic brain injury
CNS infection
Brain tumours
Stroke
What are the other associated factors of epilepsy?
Alzheimer’s
Prenatal injuries
Family history
What are some of the clinical features of epilepsy
Abnormal taste, smell and touch sensations
Deja Vu
Jamais vu (familiar situation feels unfamiliar)
Abdominal sensations
What is a focal seizure?
Seizure that occurs in a localised part of the brain which leads to symptoms in one side of the body/ one specific body part.
How does a focal seizure differ from a general event?
General seizure will affect the whole body whereas a focal seizure will result in more localised, different symptoms
Where do most focal seizures typically occur?
Frontal lobe
What are the smyptoms of a focal seizure at the temporal lobe?
Memory loss
Speech production affected
Smacking lips
Picking at clothes
Why do seizures develop in the first place (ie what is their mechanism?)
Imbalance between the excitatory and inhibitory input within regions of the brain (GABA and glutamate imbalance)
What is the target for Diazepam?
GABA-A receptor
What is the target for Lamotrigine?
VGSC
What is the target for Pregabaline?
VGCC
What is the target for Levetiracetam?
Synaptic vesicle protein SV2A (for glutamate)
What is the target for Tiagabine?
GABA reuptake transporter
What is the target for Vigabratin?
GABA transaminase
What is the mechanism of action for Diazepam?
Increase activation of receptor to increase Cl- influx
What is the mechanism of action for Lamotrigine?
Blocks VGSCs in excitatory (glutaminergic) neurones
What is the mechanism of action for Pregabaline?
Blocks VGCCs in excitatory (glutaminergic) neurones
What is the mechanism of action for Levetiracetam?
Interferes with SV2A to reduce vesicular fusion and thus exocyotsis of glutamate
What is the mechanism of action for Tiagabine?
Inhibits reuptake transporter so GABA stays in synapse for longer and increases activation of GABA A receptor therefore more Cl- influx.
What is the mechanism of action for Vigabratin?
Blocks enzyme to cause GABA build up and therefore reduce the concentration gradient between the pre synaptic terminal and the synapse. This means there is a lower reuptake of GABA and thus it remains in synapse longer, causing more activation and Cl- influx.
