(PM3B) Epilepsy Flashcards
What percentage of the population are affected by epilepsy?
~1%
What is epilepsy?
Neuronal hyperexcitability disorder
Arises from excess excitability/ disinhibition
What is disinhibition?
Inability to suppress inappropriate behaviour
What are the principle types of seizure?
(1) Partial seizures
(2) Generalised seizures
How is epilepsy most often characterised?
(1) Convulsions – impairment of motor activity
(2) Impaired consciousness
(3) Impaired perception
(4) Impaired behaviour
Why is the term ‘fit’ now archaic when referring to a seizure?
Implies it is voluntary
What is the most prevalent symptom of epilepsy?
Seizures
Is a seizure the same as epilepsy?
No
Seizures are a symptom of epilepsy
Epilepsy is not a seizure
What is a convulsion?
Sudden, violent, irregular movement of a limb or of the body, caused by involuntary contraction of muscles
Is a convulsion the same as a seizure?
No
A seizure is a type of convulsion
A seizure is a convulsion due to epileptiform brain activity
Is an isolated seizure considered to be epilepsy?
No
What are some possible triggers of an isolated seizure?
(1) CNS infection/ inflammation
(2) Stroboscopic lighting
(3) Metabolic dysfunction
(4) Head injury
(5) Fever
(6) Drug-related
How can an isolated seizure be associated with epilepsy?
Repeated isolated seizures can increase risk of epilepsy development
What are some co-morbidities of epilepsy?
(1) Depression
(2) Anxiety
(3) Cognitive decline
(4) Agitation/ anger
(5) Suicide
(6) ADHD
(7) Reproductive problems
(8) Insomnia
(9) Migraine
What association is there between Alzheimer’s disease and epilepsy?
There is an increased prevalence of seizures in patients with AD
What seizure types are there?
(1) Generalised
(2) Partial
(3) Secondary generalisation
(4) Simple/ complex
What is a generalised seizure?
Involves entire brain
Tonic-clonic/ absence seizures
What is a partial seizure?
Involves one specific area of the brain
What is a secondary generalisation seizure?
Partial seizures which can spread to affect the whole brain
What is a simple seizure?
A partial seizure
Unimpaired consciousness
What is a complex seizure?
A partial seizure
Impaired consciousness
How is a tonic-clonic seizure characterised?
Impairment of consciousness + motor activity
How is a myoclonic seizure characterised?
Impairment of motor activity ONLY
Jerking of limbs
How is an absence seizure characterised?
Brief periods of reduced awareness
Impairment of attention + consciousness
How is a partial seizure characterised?
Depends on lobe affected
Frontal/ parietal/ occipital/ temporal
What is a grand-mal seizure?
Archaic name for a tonic-clonic seizure
What is a tonic-clonic seizure?
(1) Rigidity for approx. 1 minute
(2) Violent jerking of limbs for approx. 2-4 minutes
(3) Feelings of confusion, illness, and disorientation following recovery
What is a generalised absence seizure?
Occur frequently
Less physically dramatic
Typically stares vacantly ahead, unaware of surroundings
Tends to recover quickly with no after effects
What are partial seizures?
Remains restricted to a local brain area
Accompanied by simple symptoms
e.g. involuntary movements/ abnormal sensory experiences
Rarely lose consciousness
e.g. Jacksonian epilepsy, psychomotor epilepsy
What are the main aims of pharmacological treatment of epilepsy?
(1) Reduce number of seizures (ideally to 0)
(2) Maximise quality of life
What are the principle treatments for epilepsy?
(1) Sodium channel blockers
(2) Enhancement of GABA action
(3) Vagal nerve stimulation
Why are sodium channel blockers used in treatment of epilepsy?
Prevention of action potential generation
Inhibition prevents/ ameliorates seizures
e.g. phenytoin, carbamazepine, valproate
Why are GABA enhancers used in treatment of epilepsy?
Enhancement of GABA-mediated Cl- channels
Increases inhibition
Leads to attenuation of seizures
e.g. phenobarbitone, diazepam
What are AEDs?
Anti-epileptic drugs
