Clinical Epileptology Flashcards
What is epilepsy
- chronic brain disorder characterised by enduring predisposition to generate epileptic seizures
- defined by recurrent unprovoked (= spontaneously occurring) seizures
Frequency of seizures in epilepsy
10-20/month, each epilepsy lasting a minute
Interictal state
between seizures; important for EEG as epilepsy occasion is rarely recorded
Epileptogenesis
process by which a normal brain becomes epileptic potentially due to accidents/brain injury etc
Epileptic seizure
symptoms of paroxysmal change in behaviour due to synchronised rhythmic firing of populations of CNS neurons
Ictogenesis
process of induction, propagation and termination of seizures against the background of an interictal (time in between seizures) state in established epilepsy
Classification/level of epilepsy
- Symptom (focalised or generalised)
- Syndrome (focalised or generalised): collection of symptoms
- Disease (symptomatic/genetic or idiopathic/secondary)
Epileptic seizure is diagnosed
electroclinically = recording and behavioural symptoms
Level of focal seizures
origination from one side of hemisphere
- focal aware: preserved (no loss) of consciousness
- focal impaired awareness: impaired consciousness
- focal to bilateral tonic-clonic: loss of consciousness
Types of generalised seizures
origination from both side of hemisphere
- absence
- myoclonic: brief, shock-like jerks of a muscle or a group of muscles upon waking up; conscious but have no control over your body
- tonic: muscle stiffness & loss of consciousness
- clonic: jerking of the body
- tonic-clonic
- atonic: loss of muscle tone
How often is each type of seizures
focal aware: 15%
focal impaired: 25%
focal to bilateral: 35%
generalised:25%
Difficulty of absence seizures
Especially for young kid, it is hard to recognise the seizure but rather see it as a “slow/unresponsive” child
New type of epileptic seizure classification
- Onset (focal/generalised/unknown)
- awareness (intact/impaired)
- Symptom (motor or nonmotor)
nonmotor can include autonomic, cognitive, emotional, sensory, typical (5-10s), atypical (10-15s)
Localisation of focal aware non-motor seizures
e.g. aura
It can be used to assess how the symptom is progressing within the brain
-seizure in occipital lobes 5%
-parietal lobe 5%: paraestheia知覚異常 and/or vertigo
Jacksonian seizure-phenomenon where a simple partial seizure spreads from the distal part of the limb toward the ipsilateral face
-frontal lobe 25%: tonic/clonic movement
-temporal lobe 65%
lateral temporal lobe 10% (auditory symptoms)
mesial TL 90% (psychic/depressed or autonomic
symptoms)
Hyperkinetic symptoms
Where the limbs/body parts are swinging; patients fully aware but cannot control
Do not misdiagnose epileptic seizure with
- syncope/fainting
- psychogenic non-epileptic seizure
Generalised epilepsy
Easier to treat with drugs and can go drug free after some years
Most common type of epilepsy
focal, unknown etiology
history/clinical data of focal epilepsy vs generalised
focal
• partial or partial onsetseizures
• seizures during sleep
general
• generalised seizures
• 30 min after awakening
• positive family history
EEG of focal epilepsy vs generalised
focal
• focal slowing or hyperexcitability
general
• generalised hyperexcitability
cMRIof focal epilepsy vs generalised
focal
• structural lesion
generalised
• not helpful, always negative
Etiology of epilepsy
Most of the time unknown but it could be... structural genetic metabolic infectious immune