Epilepsy and Fits/Funny turns/Seizures Flashcards
What are types of generalised seizures?
- Absence seizures
- Generalised tonic-clonic seizures
- Juvenile myoclonic epilepsy
- Myoclonic seizure
- Clonic seizure
- Tonic/Atonic seizure
What are causes of a provoked seizure?
- Alcohol withdrawal
- Drug withdrawal
- Within a few days of head injury
- Within 24 hours of stroke
- Within 24 hrs neurosurgery
- Severe electrolyte disturbances
- Eclampsia
What are the different types of focal seizures?
- Simple partial Seizures
- Complex Partial seizures
- Partial seizures with secondary generalised
What are features of absence seizures?
“Petit-Mal”
Loss of awareness and a vacant expression for <10 seconds before returning abruptly to normal and continuing as though nothing had happened.
Apart from slight fluttering of the eyelids there are no motor manifestations.
Patients do not realise they have had an attack
What can absence seizure be provoked by?
- Hyperventilation
- Photic stimulation
Who do absence seizures occur most commonly in?
Children
What is a myoclonic seizure?
https://www.youtube.com/watch?v=xzBBezFqVMo
Myoclonic seizures or ‘jerks’ take the form of momentary brief contractions of a muscle or muscle groups, e.g. causing a sudden involuntary twitch of a finger or hand.
What prodromal features of Tonic-Clonic seizures?
- Often no warning
- Can have an aura - strange feeling in gut, deja-vu, strange smell, flashing lights
What are features of the tonic phase of a tonic clinc seizure?
10-60 seconds
- Rigidity
- Epileptic cry
- Tongue biting
- Incontinence
- Hypoxia/cyanosis – no breathing during this phase
What are features of the post-ictal phase of tonic-clonic seizures?
Period of flaccid unresponsiveness, followed by gradual return of awareness with Confusion + Drowsiness lasting from 15 minutes to 1 hour. Headache is common in tonic-clonic seizures
What are tonic seizures?
https://www.youtube.com/watch?v=vjnzFZ0wrJU
Seizures consisting of stiffening of the body, not followed by jerking
What is the definition of epilepsy?
A recurrent tendency to spontaneous, intermittent, abnormal electrical activity in part of the brain, manifesting as seizures. Convulsions are the motor manifestations of electrical discharge
What are the features of simple partial seizures?
- Focal motor/sensory/autonomic/psychic symptoms
- Awareness is unimpaired
What are focal seizures most often seen in?
Structural disease in one hemisphere
What are the features of complex partial seizures?
- Can have aura and post-ictal phase
- Impaired awareness - lasting for 1–2 minutes on average
- Retrograde amnesia
- Speech arrest
- Automatisms – semi-purposeful stereotyped motions such as lip smacking or dystonic limb posturing, or more complex motor behaviours such as walking in a circle or undressing.
What are examples of automatisms seen in complex partial seizures?
- Lip smacking
- Dystonic limb posturing
- Walking round in circles
- Undressing
Where do complex partial seizures most commonly originate from?
Temporal lobe (60%) or frontal lobe
What are aura features that individuals can experience when they have complex partial seizures?
- Rising epigastric sensation and nausea
-
Hallucinations:
- Déjà vu or jamais vu
- Olfactory hallucinations
- Formed visual hallucinations or misperceptions
- Fear
What proportion of those with partial seizures develop secondary generalised seizures?
2/3rds
What features would localise seizure source to the temporal lobe?
- Automatisms
- Emotional disturbance
- Hallucinations
- Delusional behaviour
- Bizarre associations
- Dysphasia
- Deja-vu
What features would localise a focal seizure to the frontal lobe?
- Motor features - posturing, peddling movement
- Jacksonian march
- Motor arrest
- Subtle behaviour disturbance
- Dysphasia/speech arrest
- Todd’s Paralysis
What is jacksonian march?
https://www.youtube.com/watch?v=5OADO9ucNiM
Spreading of focal motor seizure with retained awareness, often starting with face or thumb
What features of a focal seizure would imply it origintaed in the parietal lobe?
- Sensory disturbances - tingling, numbess, pain
- Motor disturbance - spreda to precentral gyrus
What features of a focal seizure would point to it having originated in the occipital lobe?
Visual phenomena
- Spots
- Lines
- Flashes
What is Todd’s paralysis
Transient neurological deficit (paresis) following a seizure. May have:
- Weakness in face, arms, legs
- Aphasia
- Gaze palsy
Lasts for 30mins to 36 hrs
What would you differential diagnosis be for a fit/seizure?
- Idiopathic epilepsy - known or new
- Brain tumour
- Meningitis
- Hypoxia
- Alcohol withdrawal
- Hypoglycaemia
- Hypotension
- Severe electrolyte distrubance
- Pseudoseizure
What are causes of epilepsy?
- Idiopathic
- Cortical scarring - due to previous head injury
- Developmental problems
- Degenerative conditions
- SOLs
- Stroke/Vascular malformations
- Hippocampal sclerosis
- Tuberous Sclerosis
- SLE
- Encephalitis
- Metabolic abnormalities
- Hydrocephalus
- Drugs/Alcohol withdrawal
What is primary generalised epilepsy?
Epilepsy caused by a structurally normal brain but abnormalities of ion channels influencing neuronal firing, abnormalities of neurotransmitter release and synaptic connections.
What are features of the clonic phase of tonic clonic seizures?
Seconds to minutes
- Convulsions/limb jerking
- Eye rolling
- Tachycardia
- No breathing/random, uncoordinated breaths
What drugs can cause epilepsy?
- Drugs for neurological/psychiatric disorders - e.g. TCA’s, MAO inhibitors, amphetamines, propofol
- Drug withdrawal – e.g. anticonvulsants
- Alcohol induced hypoglycaemia
- Alcohol withdrawal
What are automatisms?
Complex motor phenomena with impaired wareness, from primative oral to manual movements/complex actions
What is the pathophysiology of epilepsy?
Abnormal SYNCHRONISED discharge of many neurons - Normal inhibitory mechanisms fail.
What is the main excitatory neurotransmitter involved in epilepsy?
Glutamate
What is the main inhibitory neurotransmitter involved in epilepsy?
GABA
What metabolic abnormalities can cause epilepsy?
- Hypoglycaemia
- Hypocalcaemia
- Hyponatraemia
- Hypoxia
- Uraemia
- Mitochondrial disease
What are triggers of epileptic seizures?
- Sleep deprivation
- Alcohol (alcohol intake AND alcohol withdrawal)
- Drug misuse
- Physical/mental exhaustion
- Flickering lights – cause primary generalised epilepsy only
- Infection / metabolic disturbance
What are the different primary generalised seizures in children?
- Childhood abscence epilepsy
- Juveniale absence epilepsy
- Juvenile myoclonic Epilepsy
What is the age of onset of childhood absence epilepsy?
4-8 years - 80% remit by age 18
What is the age of onset of juvenile absence epilepsy?
10-15 years
What is the age of onset of juvenile myoclonic epilepsy?
15-20 years
What are features of juvenile myoclonic spilepsy?
- Morning Myoclonic seizures
- Progress to GTCS
- Can also have absence
What can trigger epileptic seizures in juvenile myoclonic epilepsy?
- Sleep deprivation
- Alcohol/Alcohol withdrawal
- Flickering lights
Does juvenile myoclonic epilepsy remit without treatment?
No - usually require lifelong treatment
What is the main pathological cause of temporal lobe epilepsy?
Hippocampal sclerosis - damage with scarring and atrophy of the hippocampus and surrounding cortex
What is the commonet cause of epilepsy after the age of 60?
Vascular disorders - stroke/CVA
How would you approach taking a history for someone who had had a first seizure?
- Pre/Ictal/Post-ictal experiences - seizure or syncope
- Collateral history - seizure form, tongue biting, incontinence etc.
- Previous fits/funny turns - including other types of seizures
- Triggers - seizures or syncopal
- Epilepsy risk factors - significant head injury, meningitis/encephalitis, FH
- Alcohol excess/Medications
- Driving
What investigations would you consider doing in someone who had presented with a seizure?
- Thorough neuro exam and basic observations (esp. temperature)
- ECG
- EEG
- Consider CT/MRI
- Bloods - U+E’s, Glucose, LFTs, Ca2+, CK, Prolactin
- Consider Blood Cultures/LP
- Toxicology screen
Why is it important to measure temperature in someone presenting with a seizure?
Look for sign of infection as a cause. Could also indicate illicit drugs e.g. amphetamine use
Why is a thorough neuro exam impiortant when investigating someone presenting with a seizure?
Look for signs of a cause:
- Signs of SOL
- Signs of stroke
- Signs of degenerative disease
Why might you do an ECG in someone presenting with a seizure?
Look for cardiogenic causes of LOC
Why might you do a serum calcium level in someone presenting with seizures?
Look for hypocalcaemia as a cause
Why might you do serum U+E’s in someone presenting with seizures?
Look for metabolic causes of seizures:
- Uraemia
- Hypo/hypernatraemia
Why would you measure blood glucose in someone who had presented with a suspected seizure?
Look for signs of hypoglycaemia
Why might you do an LP in someone presenting with a suspected seizure?
Look for signs of meningitis/infection
Why might you consider doing a toxiclogy screen on someone presenting with suspected seizures?
Look for drug intoxication e.g. amphetamines
Why might you look at drug levels (e.g. anti-epileptic drugs) in the blood of someone presenting with suspected seizures?
Look to see if they have therapeutic levels in their blood i.e. are they compliant??
Why might you consider doing a CK in someone presenting with a suspected seizure?
Raised in true epileptics after clonus and tonic seizures, normal in pseudoseizures
Why might you look at the serum prolactin levels in someone presenting with suspected seizures?
Raised in true seziures, not raised in pseudo-seizures
Why can EEG be a useless test?
EEG is usually normal inbetween fits, and an abnormal EEG between fits does NOT confirm the suspected event as epilepsy either
How might you elicit an abnormal interictal EEG?
- Sleep deprivation EEG
- ‘Activated EEG’ – after the patient has been given procyclidine
- 24-48 hour EEG – often with simultaneous video of patient to asses clinical signs – called videotelemetry.
What is EEG most useful for?
Categorizing epilepsy and understanding its cause, rather than as a means of confirming a doubtful diagnosis of epilepsy.
What are indications for CT/MRI in someone presenting with suspected seizures?
- Late onset disease
- Partial seizures
- Associated with abnormal clinical signs
What tests can you do to differentiate a true seizure from a pseudoseizure?
- Serum CK
- Serum Prolactin
- Consider EEG…
What is the commonest error in diagnosis in someone presenting with a suspected seizure?
Misdiagnosis of a syncopal blackout as a seizure.
What advise would you give someone after a first confirmed seizure?
- Avoid/remove precipitants - drugs, alcohol, sleep deprivation
- Safety advise - swimming, baths, working with weights etc
- Stop driving/Inform DVLA
- Discuss recurrence risk
- Individualised advice - employment, insurance, sports
What is the recurrence risk of a seizure after a first seizure?
- 70-80% - within first 6 months
- Unprovoked - 30-50%
What are risk factors for recurrent seizures?
- Features of PGE on EEG
- Partial seizures
- Presence of structural brain lesions
When should someone be commenced on anti-epileptic drugs?
After >/= 2 seizures, confirmed epilepsy diagnosis and detialed discussion with patient regarding treatment
What are the first line treatments for Focal (partial) seizures?
Carbemazepine or Lamotrigine
What are second line AEDs for treating Focal (partial) seizures?
- Sodium Valproate
- Leviteracetam
- Oxcarbazepine
What are first line AEDs for treating Generalised Tonic-Clonic Seizures?
Try in this order
- Sodium Valproate
- Lamotrigine
Then consider second line
What are second line AEDs used to treat Generalised tonic-clonic seizures?
- Carbemazepine
- Clobazam
- Leviteracetam
- Topiramate
What are first line AEDs for treating Absence seizures?
- Sodium Valproate
- Ethosuximide
What second line AEDs would you consider for treating Absence seizures?
Lamotrigine
What AEDs would you use first line as treatment for Myoclonic seizures?
Sodium valproate
What AEDs woule you use as second line treatment for myoclonic seizures?
- Leviteracetam
- Topiramate
What AEDs would you consider using to treat tonic/Atonic seizures?
- Sodium Valproate
- Lamotrigine
What medications would you avoid using when treating myoclonic seizures?
May worsen seizures
- Carbemazepine
- Oxcarbazepine
How would you initiate someone with epilepsy on AED treatment?
Build-up doses over 2-3 months, until seizures controlled/max dose reached
If, when testing treatment effectiveness for treating someone with epilepsy, they either did not tolerate the drug or reached the maximum recommended dose with no/limited effectiveness, what would you consider doing?
Switch to next most appropriate
When switching AED in someone with epilepsy, what are important things to do?
- Introduce second drug slowly
- Remove 1st drug once second drug has established effect
What proportion of epileptics require dual adjunct therapy?
<10%
When would you consider stopping an AED in someone with epilepsy?
- Patient has been seizure free for >/= 2 years
- Risk/benefit assessment
What surgical options are available in epileptics?
- Temporal lobectomy
- Corpus collosal section
- Hemispherectomy
- Selective amygdalo-hippocampectomy
Who would benefit most from a temporal lobectomy?
Epileptics with epilepsy caused by hippocampal sclerosis
What are side effects of carbemazepine?
- Leucopenia
- Diplopia
- Blurred vision
- Impaired balance
- Drowsiness
- Mild generalised erythematous rash
- SIADH
What are side effects of lamotrigine?
- Maculopapular rash
- Diplopia
- Blurred vision
- Photophobia
- Tremor
- Agitation
- Vomiting
- Aplastic anaemia
What are side effects of leviteracetam?
- Depression/agitation
- D+V
- Dyspepsia
- Drowsiness
- Diplopia
- Blood dyscarias
What are side effects of sodium valproate?
- Teratogenic effects
- Nausea
- Liver failure
- Pancreatitis
- Hair loss
- Oedema
- Ataxia
- Tremor
- Thrombocytopenia
- Encephalopathy
If you started someone on sodium valproate, what would you want to monitor for (especially in the first 6 months)?
LFTs - watch for liver failure
What is the risk of foetal abnormalities in someone who is pregnant with epilepsy?
5% - good seizure control prior to conception and during pregnancy is therefore vital!!!
What epileptic drugs are teratogenic?
Sodium Valproate
What drugs used in the management of epilepsy induce liver enymes?
- Carbemazepine
- Phenytoin/Phenobarbital
- Barbituates
What implication does a woman of child bearing age who has epilepsy and is on carbemazepine have for her?
May need to adjust dose of contraceptive pill - carbemazepine is liver enzyme inducer
What advise should you give pregnant women with regard to managing their epilepsy and reducing risk of harm to the foetus?
- Folic acid - 5mg/day - before conception and during first trimester
- Avoid sodium valproate and polytherapy - conception and pregnancy
- Advise most AED drugs are present in breast milk
When are patients with epilepsy not allowed to drive?
- Medication change in the last 6 months
- Seizure in the last 12 months
- If the patient has ‘night-time’ only seizures, they can drive, if they have not had a ‘day time’ seizure for the last 3 years
- If the risk is >2% of having a seizure, then you are not allowed to drive (normal lifetime risk is 1-2%)
When are patients with epilepsy allowed to drive?
Situation specific - consider if safe if:
- Seizures which do not affect consciousness (simple partial)
- Seizures only during sleep and no daytime seizures for 3 years
Are epileptic patients safe to fly on aeroplanes?
Yes
