Epilepsy Flashcards
What is an epileptic seizure
Transient occurrence of signs/symptoms secondary to abnormal excessive neuronal activity in cerebral cortex
What are convulsions
Rapid and repeated muscle contractions leading to uncontrolled shaking of body
It is a form of clinical manifestations of seizure
What is an aura
Perceptual disturbance experienced by some prior to a seizure
What is epilepsy
Brain disorder characterised by enduring predisposition to generate seizures, and by neurobiological/social/cognitive/psychological consequences of the condition
What is status epilepticus
Medical emergency characterised by continuous seizures and incomplete recovery inbetween them, lasting >5 minutes
How are seizures classified
What are the classifications
By neuronal activity + clinical manifestation
Partial:
Simple
Complex
Secondarily generalised
Generalised: Tonic clonic Absence Myoclonic Tonic Atonic
What are partial seizures
Focal excessive neuronal activity, localised to part of the brain
What are the subtypes of partial seizures
Simple partial - no loss of consciousness
Complex partial - impaired consciousness
Secondarily generalised - partial seizure spreads and becomes generalised seizure
What are clinical manifestations of temporal lobe epilepsy
Auras:
Sensory - auditory, visual, olfactory, gustatory, rush of memories
Psychic - Deja vu, Jamais vu (unfamiliarity)
Lip smacking
Amnesia
What are clinical manifestations of frontal lobe epilepsy
Abnormal muscle movement Of any part of motor homunculus on contralateral side
Dysphasia
What are clinical manifestations of parietal lobe epilepsy
Somatosensory - Tingling, numbness on contralateral side
What are clinical manifestations of occipital lobe
Visual - Flashes of light, patches of darkness on contralateral visual field
What is generalised seizure
Widespread Abnormal neuronal activity in brain, arises from a foci and rapidly spreads bilaterally
It occurs with loss of consciousness
What are clinical manifestations of tonic-clonic seizures
What can precipitate this
Sudden onset LOC followed by
- Tonic stage: body stiffens up for 1min
- Clonic stage: rapid repeated contractions of all 4 limbs causing uncontrolled shaking, for 1 mins
- Relaxed + unconscious stage
Strobe lighting, hyperventilation
What are clinical manifestations of absence seizures
What might this be precipitated by
At What age group does this occur
Sudden LOC followed by
‘Blank’ period lasting 30s
With muscle twitching of face and hands
Return without post-ictal confusion and patient unaware of LOC
Relaxing after Mental/physical exercise
4-14yo
What are clinical manifestations of myoclonic seizures
Sudden LOC followed by uncontrolled body shaking due to rapid and repeated muscle contractions
What are clinical manifestations of Tonic seizures
Sudden LOC followed by sudden stiffening of body due to increased muscle tone
What are clinical manifestations of atonic seizure
Sudden LOC followed by sudden loss of muscle tone causing patient to drop down
Aka. Drop attack
What do you need to ask in clinical history for seizures
Must also have a collateral history Before: Triggers Aura First sign/symptom
During:
Description of seizure
Duration
Abrupt/gradual end
After: Post-ictal state Tongue biting Incontinence Neurological deficit Bleeding after fall
What are main differentials of epileptic seizure
Stroke/TIA Meningitis Intracerebral haemorrhage (trauma) Autoimmune - SLE Metabolic - hypoglycaemia, electrolyte, hypoxia Iatrogenic - alcohol withdrawal, drugs Neoplastic - intracerebral mass
What investigations are used
EEG
MRI
What are indications and contraindications of EEG
What do you do if EEG results are inconclusive
To support diagnosis when Hx suggests epileptic origin
In isolation to make a diagnosis - NOT a diagnostic test
Probable syncope - risk of false +ve
Hx suggests non-epileptic origin
Repeat EEG
Sleep EEG
Ambulatory EEG
What imaging investigation is used for seizures
MRI - imaging of choice
In all patients with new onset seizures
To exclude SOL
Why is status epilepticus a medical emergency
High mortality: risk of vomiting + aspiration, blocked airway + hypoxia, permanent neuronal damage
