What is a seizure?
- Transient occurence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain
What is the definition of epilepsy?
- Epilepsy is defined by any of the following:
- At least two unprovoked seizures occurring more than 24 hours apart
- One unprovoked seizure and a probability of further seizures similar to the general recurrence risk after two unprovoked seizures (around 60%)
- At least two seizures in a setting of reflex epilepsy
NB - Epilepsy is considered no longer present for individuals who had age-dependent epilepsy syndrpome but are not past the applicable age for those who have remained seizure free for at least 10 years off medication.
What are focal (partial/localisation related) seizures?
- Area of abnormality in otherwise normal brain
- Caused by head injury, stroke, hypoxia, infection, vascular malformations and birth injuries
- Localised gliosis
- Can stay localised or can spread
What are generalised tonic-clonic seizures?
- Whole brain is affected
- Way they metabolise neurotransmitters, ion-channelopathy, difference in binding sites
- Result of genetic problems
- Genetic Generalised Epilepsy (GGE)
What are the features of focal seizures?
- Can be aware or have impaired awareness
- History of trauma or birth injury
- Focal aura/sequalae (gustatory/sensory/motor)
- Post-attack confusion/drowsiness
- Nocturnal events
- Motor onset:
- Automatisms
- Atonic
- Clonic
- Epileptic spasms
- Hyperkinetic
- Myoclonic
- Tonic
- Non-motor onset:
- Autonimic
- Behaviour arrest
- Cognitive
- Emotional
- Sensory
What are the features of GGE?
- Photosensitivity
- Age of onset 8-26yrs
- Alcohol
- Sleep deprivation
- Lack of aura
- Seizures within 2 hrs of awakening
- FHx of IGE
- Abnormal EEG
- Motor
- Tonic-clonic
- Clonic
- Tonic
- Myoclonic
- Myoclonic-tonic clonic
- Myoclonic-atonic
- Atonic
- Epileptic spasms
- Non-motor (absence)
- Typical
- Atypical
- Myoclonic
- Eyelid myoclonia
What can EEG be used for in epilepsy?
- EEG can be used to classify epilepsy and is useful to tell you the risk of recurrence
- Cannot be used for undiagnosed blackouts
How is focal epilepsy treated?
- Lamotrigine
- Carbamazepine
- Levetiracetam
How is generalised epilepsy treated?
- Valproate
- Levetiracetam
- Lamotrigine
How is status epilepticus managed?
- General measures
- ABCDE
- Establish aetiology
- Alert anaesthetist/ITU it established
- Transfer to ICU if refractory
- AED therapy
- Prehospital
- Diazepam 10-20mg PR or Midazolam 10mg bucally
- Early status
- Lorazepam IV 0.1mg/kg repeated after 10-20 minutes
- Give AED if already on treatment
- Established status
- Phenytoin infusion
- Refractory status
- Propofol
- Midazolam
- Thiopental sodium
- Continue 12-24 hrs after last clinical seizure or elctrographic seizure
- Prehospital
Dravet syndrome
- An epilepsy with a genetic cause
- Onset in 1st yer of life with febrile seizures (typically 3-9 months)
- Prolonged unilateral or generalised clonic seizures
- Other seizure types by 1-4 years
- Myoclonus
- Focal seizures
- Atypical absences
- Hyperthermia often precipitant (bathing, fever)
- Onset in absence of an infection or structural brain lesion
Classification of non-epileptic seizures and events
- Syncopes
- Psychological/behavioural events
- Sleep related events
- Paroxysmal movement disorders
- Migraine and disorders possibly related to migraine
- Miscellaneous neurological and non-neurological events
Reflex anoxic seizure/reflex asystolic syncope
- Syncope triggered by an unpleasant event, often a bump on the head, scratch, seeing blood
- Neurogenic syncope with profound bradycardia and asystole
- Child goes white as a sheet, may have an anoxic seizure, children may sleep for a while after event
Prolonged expiratory apnoea/breath holding
- Anoxic seizure after not breathing back in following an unpleasant stimulus/crying
- Child goes progressively blue
- May become cyanosed and then have an anoxic seizure
Behavioural events
- Often defined as involuntary, patterend, coordinated, repetitive, often rhythmic, non-reflexive movements that are goal directed and ocur in the same fashion with each repitition
Narcolepsy with cataplexy
- Excessive daytime sleepiness
- Cataplexy
- Hypnagogic hallucinations
- Sleep paralysis
- Disturbed night time sleep
Management of generalised tonic-clonic seizures (tonic - muscle tensing, clonic - muscle jerking)
- 1st - sodium valproate
- 2nd - lamotrigrine or carbamazepine
Management of focal seizures (hearing, speech, memory, emotions)
- 1st - carbamazepine or lamotrigine
- 2nd - sodium valproate or levetiracetam
Management of myoclonic seizures (brief muscle contractions, awake throughout)
- 1st - sodium valproate
- 2nd - lamotrigine, levetiracetam or topiramate
Management of absence seizures (becomes blank)
- 1st - sodium valproate or ethosuximide
Management of atonic seizures (drop attacks, brief loss in muscle tone)
- 1st - sodium valproate
- 2nd - lamotrigine
Management of infantile spasms (clusters of full body spasms)
- Prednisolone
- Vigabatrin
Side effects of sodium valproate
- Teratogenic
- Liver damage and hepatitis
- Hair loss
- Tremor
Side effects of carbamazepine
- Agranulocytosis
- Aplastic anaemia
- Induces the P450 system
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Clinically Applied Neuroanatomy18
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Headache18
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Cerebrovascular Accident (CVA)18
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Epilepsy28
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Subarachnoid Haemorrhage6
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GCS4
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Mononeuropathies6
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Multiple Sclerosis8
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Parkinson's Disease6
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Peripheral Neurology10
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Microbiology VTL - Infections of the CNS6
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Dementia and Delirium32
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Stroke by Anatomy9
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Dermatomes17
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Movement Disorders13
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Spinal Cord Lesions11
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Raised ICP and Hydrocephalus9
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Neurophysiology5
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Head Injury4
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Motor Neurone Disease (MND)5
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Facial Nerve Palsy6
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Brain Tumours3
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Myasthenia Gravis6
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Lambert-Eaton Myasthenic Syndrome (LEMS)3
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Charcot-Marie Tooth Syndrome4
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Neurofibromatosis5
