Epilepsy Flashcards
What is Epilepsy?
A disease of the brain defined by the following:
- At least two unprovoked siezures occuring more than 24 hours apart
- One unprovoked seizure and a probability of further seizures similar to the general recurrence risk, after two unprovoked seizures, occurring over the next 10 years
- Diagonsis of an epilepsy syndrome
Does a single seizure mean epilepsy?
No
As a seizure can be caused by many different factors includi g toxins, infections and metabolic disturbances.
What is the definition of a seizure?
A seizure is the transient occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
What are the potential causes of Epilepsy?
- Structural abnormalities within the brain
- Genetic mutations resulting in epilepsy (not necessarily inherited genetics)
- Infectious causes in which seizures are a core symptom of the disorder, e.g. cerebral malaria,
tuberculosis - Metabolic issues such as porphyria or pyridoxine deficiency
- Immune disorders in which seizures are a core symptom of the disorder, e.g. anti-NMDA receptor
encephalitis
What are some complications of Epilepsy?
- Sudden Unexpected Death in Epilepsy (SUDEP)
- Injuries and accidents (e.g. drowning, road traffic accidents, falls)
- Depression and Anxiety
- Absence from work and / or school
What are the factors that differeniate seizures?
- Their onset
- If the patient has awareness or not
- Other symptoms
What are the three broad categories of seizures?
- Focal Onset Seizures
- Generalised Onset Seizure
- Unknown Onset Seizure
They are classified by their location of onset
What are Focal onset seizures?
Seizures that originate in networks limited to one hemisphere of the brain, and may be localised (a small part of the hemisphere) or more widely distributed (a large part of the hemisphere effected).
Sometimes a focal onset seizure can spread to both sides of the brain, called a focal to bilateral tonic-clonic seizure (aka secondarily generalised seizures).
What are the sub-classifications for Focal onset seizures?
- Focal aware seizures aka simple partial seizures
- Focal impaired awareness seizures aka complex partial seizures
This is where the patient is aware of what is happening to them or not
What is the second classification for Focal onset seizures?
After awareness, the seizures are classified into motor onset and non-motor onset.
Motor onset is with physical symptoms and non-motor onset is without physical symptoms.
What happens during focal aware and focal impaired awareness depends on what part of the brain the focus is.
What kind of symptoms are involved in motor onset?
Automatisms
Atonic
Clonic
Epileptic spasms
Hyperkinetic
Myoclonic
Tonic
What kind of symptoms are involved in non-motor onset?
Autonomic
Behavior arrest
Cognitive
Sensory
Examples of what motor symptoms focal seizures can include?
- making lip-smacking or chewing movements
- repeatedly picking up objects or pulling at clothes;
- suddenly losing muscle tone and limbs going limp or floppy, or limbs suddenly becoming stiff;
- repetitive jerking movements that affect one or both sides of the body;
- making a loud cry or scream
- making strange postures or repetitive movements such as cycling or kicking.
Examples of what non-motor symptoms focal seizures can include?
- changes or a ‘rising’ feeling in the stomach or déjà vu (feeling like you’ve ‘been here
before’) - getting an unusual smell or taste
- a sudden intense feeling of fear or joy
- a strange feeling like a ‘wave’ going through the head;
- stiffness or twitching in part of the body, (such as an arm or hand);
- a feeling of numbness or tingling;
- a sensation that an arm or leg feels bigger or smaller
than it actually is - visual disturbances such as coloured or flashing lights or hallucinations (seeing something that isn’t actually there).
What are generalised onset seizures?
Siezures that originate in bilaterally distributed networks (affect both sides of the brain), and can include cortical and subcortical structures (but not necessarily the whole cortex). These happen without warning.
So start somewhere and affects both sides of the brain at once, happening without warning.
What are the sub-classifications for Generalised onset seizures?
Motor and non-motor seizures
Examples of generalised motor seizures?
Tonic-clonic
Tonic
Atonic
What are unknown onset seizures?
Seizures where the focus hasn’t been confirmed.
This may happen when the patient was asleep, alone or the seizure was not witnessed.
What are unclassified seizures?
Seizures where there is not enough information available about the person’s seizure or because of the unusal nature of the seizure.
