Epilepsy Flashcards
What is the difference between seizure and epilepsy
A seizure refers to a transcient disturbance of cerebral function dur to an abnormal sudden, excessive and rapid electrical discharge arising from cerebral neurons
Epileptic seizure can be defined clinically as an intermittent, stereotype disturbance of consciousness, behaviour, emotionm, motor function or sensation
What is the etiology of seizures
seizures are multifocal and depend on the fine balance between 3 things
- seizure threshold
- presence of epilptogenic focus
precipitating factors or provocative events
Define: idiopathic epilepsy
seizures usually begin between 5-20 years of age but may start later on in life. No specific cause can be identified and there are no neurologic abnormailities
List some factors that may cause epilepsy
- family history
- prenatal and perinatal factors: rubella, perinatal trauma and anoxia
- trauma and surgery: severe head traumas, surgery to cerebral hemispheres
- metabolic cause: hyponatremia, hypernatremia, hypo/hyperglycaemia, chronic metabolic encephalopathies produce grey-matter injuries
- toxic cause: chronic alcohol abuse, withdrawal of antiepileptic drugs and benzodiazepine
- infectious and inflammatory cause: encephalitis, febrile convulsion, neurosyphilis
- vascular causes: most commone cause of onset at 60+
- intracranial tumour: if seizures suddenly start in adult life
- degenerative diseases: Alzeimer’s
What is a common cause of generalisedd seizures in children <5 years of age
High fever secondary to non-cerebral infections
- self-limiting and often dont recur in adult life
What is the difference between partial and generalised seizures
Partial seizures
- confined to one area of cortex
- arise from the discrete region of one cerebral hemisphere
Generalised seizures
- onset of the epileptic discharge may include the whole cortex
- arise from both cerebral hemispheres with a loss of consciousness
What is the difference between simple partial seizures and complex partial seizures
- Simple partial seizures
- consciousness not impaired
- begin with motor, sensory, or autonomic phenomena, depending on cortical region affected
- 1 to 2 minutes - Complex partial seizures
- consciousness impaired
- temporal lobe seizures
- around 30 minutes
- automatism (involuntary motor activity): sit up or stand up, fumbling with objects, lip smacking
Describe tonic-clonic seizures (grand-mal)
- generalised seizure
Tonic phase: - sudden loss of consciousness
- contraction of limb muscles, gnash teetch, eye roll or stare one side , sometimes vocalisation
- 10-30 seconds
- breathing stops, face becomes cyanotic
- urinary incontinence
- tongue/lips may be bitten
Clonic phase:
- violent generalised shaking
- 1-2 minutes
- breathing recommences at this stage
- pupilary dilation
- babinski sign (+)
Recovery:
- regain consciousness
- cannot remember what happened
- headache
- aches of muscles
- lasts 30min
Define: status epilepticus
state of continued or recurrent siezures, with failure to regain consciousness between seizures
- medical emergency
How are epilepsy seizures diagnosed
- clinical history
- clincal features
- brain imaging
- EEG
- blood test (kidney function and blood sugar and gas and electrolytes)
What are some useful clinical features for the diagnosis of epilepsy seizures
- pupil dilation
- extensor plantar responses
- face/nail bed cyanosis
- bitten tongue
- urinary incontinence
- cannot remember what happened
Brain imaginf:
- partial seizure
- refractory and recurrent seizure
- abnormal clinical signs: alalia/ glossolalia or hemiplegia
What is the differential diagnosis for seizures
- Syncope: emotional stimulation, pain, sight of blood, fatigue or prolonged motionless standing (15s & quick recovery)
- TIA
- Pseudo-seizures
How are seizures treated
- avoidance of dangerous jobs/places
- drug treatment: when 2 or more seizures happen in a short period, one anti-epileptic drug should be used and treatment should only stop if no seizures for 3 years
Drugs used for seizure treatment
1st line drug for generalised seizures in adults: sodium valporate or lamotrigine
Partial seizures: carbmazepine, lamotrigine
Status epilepticus: diazepam
Generalised tonic-clonic: valporate
List some of the side effects of anticonvulsant drugs
- hematologic and hepatic toxicity –> complete blood count and liver function tests should be obtained before initial administration of drugs as well as at intervals of treatment
- perform tests a 2 weeks, 1 month, 3 months, 6 months and then every 6 months after that
