Epilepsy Flashcards
What is a seizure?
A sudden, irregular discharge of electrical activity in the brain, causing a physical manifestation such as sensory disturbance, unconsciousness, or convulsions
What is a convulsion?
Uncontrolled shaking molecules of the body due to rapid and repeated contraction and relaxation of muscles
What is an aura?
A perceptual disturbance experienced by some prior to a seizure, e.g. a strange light, unpleasant smell, confusing thoughts
What is epilepsy?
A neurological disorder marked by sudden recurrent episodes of sensory disturbance, LOC, or convulsions, associated with abnormal electrical activity in the brain
When can epilepsy be diagnosed when there is only a single episode?
If high underlying risk through past medical history or family history
What is status epilepticus?
Epileptic seizures occuring continuously without recovery of consciousness in between
What broad categories are seizures categorised into?
- Partial, or focal
- Generalised
What are focal seizures categorised into?
- Simple
- Complex
What are generalised seizures classified into?
- Absense
- Myoclonic
- Tonic-clonic
- Tonic
- Atonic
What is the difference between focal and generalised seizures?
In focal, a small area of the brain is involved. In generalised, the whole brain is involved
What is meant by a simple partial seizure?
One where there is no loss of consciousness
What is meant by a complex partial seizure?
One where consciousness is impaired
What are the types of epilepsies causing partial seizures?
- Temporal lobe epilepsy
- Frontal lobe epilepsy
When does temporal lobe epilepsy present?
In the 1st/2nd decade in most people
What does temporal lobe epilepsy follow?
Seizure with fever, or early injury to the brain
What auras might you get with temporal lobe epilepsy?
- Auditory hallucinations
- Rush of memories
What are the stages of tonic clonic seizures?
- 1st part is tonic
- 2nd part is clonic
What happens in myoclonic seizures?
Brief, shock-like muscle jerks
What happens in atonic seizures?
Drop attacks
What investigations are done in epilepsy?
- Clinical history
- EEG
- MRI
What information is needed about before the seizure in the clinical history?
- PMH
- Family history
- Aura
- First sign/symptom
What information about during the seizure is required in the clinical history?
- Description of seizure
- Duration
- Abrupt or gradual end
What information about after the seizure is required in the clinical history?
- Post-ictal state
- Tongue biting
- Incontinence
- Neurological deficit
What are the vascular differential diagnoses for epilepsy?
- Stroke
- TIA
What are the infectious differential diagnoses for epilepsy?
- Abscess
- Meningitis
What are the traumatic different diagnoses for epilepsy?
Intracranial haemorrhage
What are the autoimmune differential diagnoses for epilepsy?
SLE
What are the metabolic differential diagnoses for epilepsy?
- Hypoxia
- Electrolyte imbalance
- Hypoglycaemia
- Thyroid dysfunction
What are the iatrogenic differential diagnoses for epilepsy?
- Drugs
- Alcohol withdrawal
What are the neoplastic differential diagnoses for epilepsy?
Intracerebral mass
What is the use of the EEG in epilepsy?
It is not diagnostic, but supports the diagnosis
What should be assessed using EEG after the first unprovoked seizure?
The risk of seizure recurrence
How is the risk of seizure reoccurence assessed on the EEG?
Looking for unequivocal epileptiform activity
What does the standard EEG assessment involve?
Photic stimulation and hyperventilation
When should an EEG not be used?
- Probably syncope
- Clinical presentation supports diagnostic of non-epileptic event
Why should EEGs not be used if there is probably syncope?
Risk of false positive result
Can EEG be used in isolation to diagnose epilepsy?
No
What actions should you consider taking if the EEG is unclear?
- Repeated standard EEGs
- Sleep EEGs
- Long-term video or ambulatory EEG
